Screw Posts

Screw posts represent a restorative anachronism. The risk of root fracture is too great compared with the benefit, particularly when reasonable and superior passive alternatives exist (see Chapter 22). Even if the screw post is initially placed passively, the temptation to turn the screw is too great, considering human nature. Therefore screw posts are not a reasonable and prudent treatment choice.

Paresthesia Prevention

Endodontic surgery in the vicinity of the mandibular canal or mental foramen carries with it the significant risk of irreversible injury to the inferior alveolar and/or mental nerve. Consequently, the clinician must advise the patient in lay terms of the risk of temporary or permanent anesthesia or paresthesia before any surgery near these structures is performed. To document that adequate informed consent was provided, the clinician should have the patient execute a written informed consent form confirming that the patient was so advised. Informed consent is no defense if the surgery was negligently chosen or performed, because informed consent only applies to non-negligent treatment risks. CBCT imaging has greatly reduced if not eliminated entirely the likelihood of IANC perforation. CBCT provides diagnostic guidance before therapy. Also, a final diagnosis confirms or rules out IANC penetration post treatment, promoting prompt removal of foreign materials piercing the IANC.

A clinician initiating root canal therapy on a mandibular posterior tooth must have (1) an awareness of the vital neurovascular bundle containing the IAN, which commonly approximates the ends of these roots, and (2) a diagnostic-quality image that accurately demonstrates the IANC. If endodontics is done without adequate diagnostic radiographs, the patient is placed at great risk if there is anatomic variation or vital neural bundles lie in close proximity to these roots.^{85,146,168,234,271} Overfilling and/or overinstrumentation of the root ends can cause traumatic and/or chemical injury to the IAN bundle, resulting in potentially permanent altered or total loss of sensation from paresthesia (partial numbness), anesthesia (total anesthesia), and/or dysesthesia (burning pain).

The risk of overfills containing toxic materials causing irreversible neuropathies results from (1) inadequate imaging of the proximity of both borders of the IANC (Fig. 11-23, A-C), (2) inadequate measurements during cone measurement, and (3) not limiting filling materials to within the confines of the shaped root canal space as further evident in CBCT.

FIG. 11-23 A, Unclear periapical to show both cortical borders of inferior alveolar nerve canal (IANC). B, Cones placed into IANC, showing measurements beyond apices. C, Overfill into IANC better shown on cone-beam computed tomography (CBCT) than periapicals of A and B.

The eugenol component of the root canal sealer part of the overfill is known to be cytotoxic. Consequently, endodontic overfill of the root apex is capable of producing not only mechanical damage¹⁸⁰ but also chemical injury. Accordingly, a prompt microsurgery referral to remove the injurious materials from the IAN inside the IANC nerve space before overfill material toxins are chemically set is mandatory.²⁰⁶ Better yet is to take precautions to prevent ANY significant injurious overfill.

The use of electronic measuring devices such as an electronic apex locator is standard technology for accuracy when working deep within the root canal system. In addition to radiographs, an apex locator helps provide accurate length readings. If it is determined that the apex is in extremely close proximity to the IANC, extra precaution must be taken to prevent overextension of instruments or materials.

Precise measurements during cleaning, shaping, and obturation compacting stages of endodontics minimizes significant overfill incidents. Obturating filling materials are not only toxic to nerve cells but also create a mechanical pressure injury to the nerve cells themselves. Immediate microsurgical referral for retrieval of any overfill materials which “harpoon” the IANC protect against irreversible neuropathies (see Fig. 11-25, C).²⁰⁶

Serious mechanical and chemical injury to the IAN results from a lack of recognition of the overfill piercing the IANC and/or disregard for neuropathic symptoms the patient reports postoperatively that are consistent with neurologic deficits.

Referral to an oral surgeon/microsurgeon is time dependent. Pogrel’s study demonstrated complete reversal of neuropathic symptoms secondary to overfill if microsurgery was done within 48 hours.²⁰⁶ Two-thirds of Pogrel’s patients gained significant improvement if microsurgery was done within 3 months of IAN overfill injuries. Delaying expeditious referral to a microsurgeon for removal of overfilled materials progressively worsens the toxic effects of the chemical injury over time. Delaying microsurgical referral risks permanent injury, owing to the time-dependent nature of overfill errors.

After 3 months, microsurgical delay will almost close the window of opportunity to prevent permanent neurologic deficits of altered sensation, with resulting pain, numbness, and painful burning symptoms extrusion overfills into the IANC can cause. Stat referral for microsurgical removal of paraformaldehyde-containing root canal filling materials and sealants is even more critically time dependent because of the greater toxicity and mummifying effects of these powders when mixed into pastes (e.g., N2 and RC2B). Risks include anaphylactic shock.^{34,99,115,155}

For needed stat referrals, the offending clinician should phone, write to, and e-mail the microsurgeon. Patients lack the expertise to promptly obtain critically time-dependent referrals. When time is of the essence, the clinician and staff must assume direct responsibility to assure the stat referral to a microsurgeon is promptly accomplished.

Treatment Failure

A clinician should not guarantee treatment success. It is foolish to assure the patient of a perfect result.⁴⁹ Endodontic failures may occasionally occur despite adequate endodontic care.^131,249 Nevertheless, negligent contributing factors to endodontic failures include perforation, missed or transported canal, uninstrumented portion of a root canal, bacterial infiltrates by way of a leaky coronal restoration contaminating the root canal filling,^48,237,241 overextension errors, and inadequate isolation of the tooth from salivary contaminants during instrumentation due to lack of a rubber dam.

To avoid claims based on failed endodontics, the patient should be advised in advance of treatment of the inherent (but relatively small) risk of failure (i.e., about 5% to 10%). It may be adequate to advise the patient of the high statistical probability of success in endodontics if the clinical condition of the tooth and the clinician’s past success rate warrant such representation.^116,236 Clinicians should avoid quoting the national success rate of endodontics when (1) the patient’s tooth is of questionable endodontic and periodontal status and (2) the clinician is known to have an unusually high endodontic failure rate—for example, a rate that varies markedly from national statistics, which also suggests referral to an endodontist.

An endodontic treating clinician is also liable for failure to disclose evident pathosis in the quadrant being treated. The patient should be advised of any periodontal disease that adversely affects the prognosis of abutment teeth for partial dentures, bridges, or an implant with a need for grafting if the endodontically treated tooth is lost. A clinician should also advise of cysts, fractures, or lesions of suspected neoplasms. In addition, the clinician must be careful not to ignore any evident pathosis that if untreated may adversely affect the dental or medical health of the patient. Again, a clinician who fails to plan treatment properly is planning for treatment failure.

The doctrine of informed consent protects both the clinician and the patient so that there will be no surprises or patient disappointment if a non-negligent adverse result occurs. Should such a failure or complication occur, the availability of a signed informed-consent form can serve as a reminder to the patient that the risk of complications, including failure, was discussed in advance of treatment and that unfortunately the patient’s endodontic treatment fell outside the usual 90% or greater root canal therapy success rate.

Slips of the Drill

A slip of the drill, like a slip of the tongue, may be unintentional. Nevertheless, it can cause harm. When a cut tongue or lip occurs, it is usually the result of operator error. To paraphrase Alexander Pope, to err is human, to forgive, divine. To increase the likelihood that a patient will forego filing suit because of a cut lip or tongue, the clinician should follow these steps:

Leakage

Long-term seal of the root canal system is determined apically by the sealer and coronally by the final restoration.^{24,106,189,237} Root canal–filled teeth should be permanently restored without undue delay to prevent leakage contamination of the previously obturated canal system, since varying canal shapes from round to oval prevent a 100% seal.^63,64,164 Bonded seals covering the canal surfaces should be used to control any leakage after compaction until a permanent restoration is cemented. Besides an adequate coronal sealing, an adequate apical sealer should be well adhered to the canal walls.

The endodontic goal is to prevent bacterial contamination of the periradicular tissue by predictably providing adequately cleaned, shaped, and filled root canal systems. Any residual bacteria should be entombed in the root canal filling. A bacteria-tight apical seal should be designed to last long term with sealed portals to prevent reentry of microorganisms, which cause reentry recontamination and lead to endodontic failure.^63,241 Younger patients are more susceptible to bacterial penetration inside dentin tubules and thus recurring infections.¹⁴³

Electrosurgery

Electrosurgery can cause problems if mishandled. Damage to the oral cavity caused by improper use of electrosurgical devices consists primarily of gingival necrosis, osteonecrosis, sloughing adjacent to the surgical field, and pulpal necrosis of affected teeth.

All equipment should be properly maintained and certified to meet the American National Standard (ADA specification no. 44 on electrical safety standards). Current equipment should be checked to see that units meet these standards and that electrical cords and other components are in good repair. Electrical receptacles should meet the requirements of the National Electrical Code for circuit grounding and ground fault protection. During use, the dispersive electrode plate should be well away from metal parts of the dental chair and the patient’s clothing, because skin contact can cause burns. Use of plastic mirrors, saliva ejectors, and evacuator tips is strongly recommended.

Reasonable versus Unreasonable Errors in Judgment

Although a clinician is legally responsible for unreasonable errors in judgment, mistakes occasionally happen despite adherence to the standards of reasonable care. A mistake does not prove malpractice unless the mistake is caused by a malpractice error or omission.¹¹² For example, accessory or fourth canals on molar teeth are frequently difficult to locate and may tax the best clinicians. Failure to locate an accessory or fourth canal does not conclusively constitute an unreasonable error of judgment. Rather, this may represent a reasonable error of judgment in the performance of endodontics. Nevertheless, if the additional canal was readily apparent radiographically, the existence of a fourth canal should have been considered, and treatment should have extended to instrumenting and sealing it.

Broken Files

Leaving broken files behind without referring the patient to an endodontist for attempted microscopic retrieval and also not advising the patient of leakage potential may constitute fraudulent concealment (Figs. 11-24 and 11-25). Patients should be informed of such mishaps for (1) referral consultation and/or treatment; (2) advising the patient, who on their own may seek a second opinion; or (3) disclosure, so as to return if a flare-up occurs.

FIG. 11-24 A, Tooth #31 with three separated files, one in each canal. K-files used for cleaning canals and also obturation (1996). B, No apparent radiographic changes in 1998.

FIG. 11-25 A, Apical radiolucent changes with draining 9 mm buccal abscess (Aug. 2003). B, Endodontist retreatment (Aug. 2003). C, Successful retreatment with no buccal pocket (Sept. 2003).

(Courtesy James YS Ho, DMD.)

Swallowing or Aspirating an Endodontic Instrument

Use of a rubber dam in endodontics is mandatory.²³⁸ Even if the endodontically treated tooth is broken down and cannot be clamped, a rubber dam, regardless of required modification, should be used in all instances (see Chapter 5). Not only is microbial contamination reduced with the use of a rubber dam, the risk of a patient’s aspirating or swallowing an endodontic instrument is eliminated (Fig. 11-26). Accordingly, if a patient swallows or aspirates a file, it is likely because of the clinician’s failure to observe the standard of care. If a swallowing or inhalation incident does occur, the clinician should do the following:

1. Advise the patient that the clinician regrets what occurred.

2. Refer the patient for immediate medical care, including radiographic imaging, to determine if the instrument is lodged in the bronchus, esophagus, or stomach so that appropriate medical measures are taken promptly to remove it.

3. Offer to pay for the patient’s out-of-pocket medical expenses and wage loss. Some professional liability policies will cover the incident as “medical payment” for an accident and not as a malpractice claim.

FIG. 11-26 Swallowed endodontic instrument demonstrates the wisdom of using a rubber dam.

Overextensions and Overfills

A common error in utilizing periapical or panorex imaging is presuming that when only one cortical border of the IANC is visible, the sole visible border is the superior border. Instead, virtually always when only one cortical border is clearly visible, it is the inferior cortical border.¹⁶⁸ (See Fig. 11-25, B periapical, which may appear to show only one cortical border, and Fig. 11-25, C, a clearer CBCT image of the same area showing both cortical borders.)

Misassumption of the IANC borders results in mismeasurement of the IANC location. Since the IANC is approximately 3 mm in diameter, misassuming the sole observable cortical canal border to be the superior border (rather than the inferior border) can result in an imprudent treatment decision to delay microsurgery if overfill occurs and the CBCT confirms an overfill inside the IANC. In Fig. 11-25, B, the defendant endodontist misdiagnosed the overfill as being superior rather than inside the IAN canal, with resultant permanent paresthesia from only watching and waiting for sensory return rather than referring for a stat microsurgical removal.

A very slight overextension of root canal filling with conventional obturation or sealants can occur without violating the standard of care (see Chapter 10). Gross overfill usually indicates faulty technique. Fig. 11-27, A-B illustrates gross overfill of calcium hydroxide, causing permanent paresthesia. Nevertheless, so long as the overextension is not in contact with vital structures such as the IAN or sinuses, permanent harm is unlikely unless the root canal is filled with a paraformaldehyde-containing sealant (causing a neurotoxic chemical burn type of injury which chemically diffuses through bone marrow and soft tissue spaces).

FIG. 11-27 A-B, Calcium hydroxide overfill, causing permanent paresthesia.

If, however, severe postoperative pain is foreseeable as a result of overextension, the patient should be advised of the likelihood of postoperative discomfort because of contact of the sealant material with surrounding tissue. Similarly, if the overextension is very slight and increased postoperative pain is unlikely, the patient need not be advised, lest it cause unnecessary alarm. A note should be made on the patient’s chart of the overextension and the reason for not informing the patient, in case symptoms later manifest. The clinician should observe with close follow-up visits and patient phone calls that evening and the next morning to rule out severe postoperative persistent numbness and/or pain resulting from moderate to large overfills. Fortunately, slight to moderate overextensions with inert conventional endodontic sealers, such as gutta-percha with Grossman’s sealant, often repair themselves and produce no irreversible changes without direct contact into the sinus or IANC.

Overextending the root canal filling material risks permanent consequences if the underlying IAN is initially “harpooned” with files. Portal of entry into the IANC results from overinstrumentation penetration. Flexible gutta-percha alone probably will not penetrate beyond the mature root into the IANC or other vital structures without prior excessive instrument perforation into the IANC.

Mental foramen distances can be overestimated on the panoramic radiograph. Panoramic radiography showed more deviation (+0.6 mm) from the perioperative measurement.^85,234 As noted earlier, paraformaldehyde-containing sealants can create cytotoxic chemical destruction of the IAN if placed in close proximity to, even though not directly contacting, the underlying IAN (see reference, Sargenti Opposition Society [SOS]).²²⁴ On the other hand, conventional obturators and sealants usually require direct contact with the IAN before resulting permanent anesthesia, paresthesia, and/or dysesthesia occurs (Fig. 11-28). Consequently, the incidence of permanent sequelae with conventional filling materials is extremely low compared with the greater cytotoxic potential with paraformaldehyde-containing sealants.¹⁹⁵ Because of the higher risks associated with paraformaldehyde-containing endodontic materials, use of N2, RC2B, or similar toxic pastes is contraindicated and violates the standard of care. Permanent injury risk is substantially less likely with traditional eugenol-containing filling materials, a less toxic chemical than paraformaldehyde, which destroys and mummifies nerve tissues. When safer, less risky alternative effective therapy exists, it is unreasonable (and substandard) to elect an unsafe alternative methodology. Also, the doctrine of informed consent is highly relevant because it is contrary to public policy to request a patient to assume inherently dangerous treatment risks that are reasonably avoidable with safer and more predictable methodologies. When the risk exceeds the benefits, such risks are regarded as negligent and thus should be avoided and not undertaken.

FIG. 11-28 A-C, Overextended gutta-percha and extracted tooth with gutta-percha intact.

Any significant overextension should be considered for immediate retreatment by attempted retrieval of the overextended gutta-percha. The clinician also has the option of immediately referring the patient to an endodontist for retrieval before the sealant sets. Conventional filling agents such as gutta-percha do not penetrate the cortical walls of the IANC unless preceded by prior penetration with overinstrumentation. This principle can apply to sinus perforation. If despite local anesthesia, the patient feels an electric shock during mandibular molar or premolar instrumentation, this may be a warning sign that the IAN was pierced with endodontic files. If this occurs, the root canal should not be filled; instead, periapical radiographs at different angles should be exposed with instruments in place to confirm whether any IAN penetration resulted. Removal of gutta-percha and sealants that have entered the IANC should be attempted as soon as possible (preferably no later than within the first 24 to 72 hours).²⁰⁶ The eugenol component of the sealant causes an inflammatory reaction in a constricted space which is best relieved by retrieval. If retrieval fails, a decortication microsurgical procedure with an oral surgeon is indicated at the earliest possible time (preferably within the first 24 to 72 hours) owing not only to eugenol chemical toxicity but also eugenol reaction with gutta-percha, which causes expansion and thus a mechanical compression ischemic injury.^180,206

Inflammatory edema that compresses and compromises blood supply to soft tissues and nerves in limited spaces with resulting ischemia is termed compartment syndrome.^230,274 Compartment syndromes are a group of conditions that result from increased pressure within a limited anatomic space, acutely compromising the circulation and ultimately threatening the function of the tissue within that space. Compartment syndrome occurs from an elevation of the interstitial pressure in a closed osseofascial compartment that results in microvascular compromise. The pathophysiology of compartment syndrome is an insult to normal local tissue homeostasis that results in increased tissue pressure, decreased capillary blood flow, and local tissue necrosis caused by oxygen deprivation. Compartment syndrome is caused by localized hemorrhage or postischemic swelling. The pathophysiology of compartment syndrome is a consequence of closure of small vessels. Increased compartment pressure increases the pressure on the walls of arterioles within the compartment. Increased local pressure also occludes small veins, resulting in venous hypertension within the compartment. The arteriovenous gradient in the region of the pressurized tissue becomes insufficient for tissue perfusion.

The clinician should have a high index of suspicion whenever a closed bony nerve compartment has the potential for bleeding or swelling. Compartment syndromes are characterized by pain beyond what should be experienced from the initial injury. Also, diminished sensation may be noted in the distribution of the nerve within a compartment that is being compressed, such as the IANC enclosed by bone on all sides.

Current Use of Silver Points

Based on what has been known for more than 3 decades, use of silver points in lieu of gutta-percha or other conventional endodontic filling materials represents a departure from the current standard of care. This is because silver points corrode in time, and a tight 3D apical seal is lost. Fig. 11-29, A-C represents gross overextension with a silver point that ultimately caused the loss of tooth #14 as a result of endodontic failure.

FIG. 11-29 Gross overfill into sinus with a silver point, which ultimately caused sinusitis and loss of tooth #14 as a result of endodontic failure.

N2 (Sargenti Paste)

Dental literature reports that permanent paresthesias are associated with gross overfilling with paraformaldehyde sealant (N2) that are not usually associated or reported with conventional sealants (Fig. 11-30).^162,195 Current use of paraformaldehyde-containing endodontic sealants is not merely the result of a philosophic difference between two respectable schools of thought. Rather, the distinction is between the reasonable and prudent school of thought that advocates conservative conventional endodontics and the imprudent and radical school of paraformaldehyde providers who unreasonably risk permanent, deleterious injury with N2 overextensions. Regardless of the small number of clinicians professing to use N2, it is cytotoxically unsafe and should be avoided. A customary negligent practice by some clinicians is no defense to safe and prudent practice, which the standard of care requires. No matter how few or how many do it wrong never makes it right.

FIG. 11-30 A-B, Overextensions of Sargenti paste filling the inferior alveolar nerve canal. Both cases could have been avoided if the practitioners had selected a conventional sealing material and used a technique that emphasizes length control.

Clinicians may be liable for fraudulent concealment, intentional misrepresentation, or co-conspiracy if they discovered that a previous clinician’s negligence is the cause of dental disease, and both the prior clinician and subsequent treater concealed the prior clinician’s negligence. For instance, if a gross overextension of a paraformaldehyde packing or sealant is evident radiographically, and the patient reports that another clinician caused the overfill (that resulted in permanent lip and chin anesthesia), subsequent treating clinicians may be liable for fraudulent concealment if they misinform the patient that the anesthesia will probably disappear shortly, and that using N2 merely reflects a philosophic difference rather than substandard practice. Reasonable clinicians who differ on therapies regard such differences as controversial. The difference between standard of care and substandard practice is not controversial but rather an indisputable difference between right and wrong. For instance, quackery based upon pseudoscience is not controversial, it is fraudulent practice.^25,185 Likewise, if the radiographs indicate sealant is inside the IANC, and the patient complains of persistent anesthesia, the patient should not be told to wait for return of sensation. The clinician should refer the patient immediately for microsurgical consultation regarding decortication and decompression surgery.

The Federal Food, Drug, and Cosmetic Act prohibits interstate shipment of an unapproved drug or individual components used to compound the drug.⁷⁶ On February 12, 1993, the FDA dental advisory panel confirmed that N2’s safety and effectiveness remain unproven. N2 may not be shipped interstate or distributed intrastate if any of the N2 ingredients were acquired interstate. Mail-order shipments of N2 from out-of-state pharmacies in quantities greater than for single-patient use are considered a bulk sales order rather than a prescription, thus violating FDA regulations.⁴⁶ A San Francisco jury awarded punitive damages against an N2-distributing New York pharmacy for knowingly shipping N2 in violation of FDA regulations, done with deliberate disregard for patient safety.¹³²

Malpractice Prophylaxis

Most negligently injured patients do not sue.³⁵ Nonetheless, litigation serves a prophylactic purpose since litigation fears make some clinicians more careful and help promote professional guidelines. For example, after the American Society of Anesthesiologists adopted practice guidelines to reduce patient harm, deaths and professional liability premiums decreased dramatically.^204,228

Disclosure Errors

Should dental negligence harm a patient, then full disclosure, including accepting the clinician responsibility along with providing an apology and explanation, results in the best outcome for the clinician and patient. Also, assurance of efforts to prevent a recurrence results in greater patient satisfaction and retains trust with the disclosing clinician to sustain a continuing clinician-patient relationship. Patients want to be told of treatment errors, regardless of whether the error can be corrected. One study in which there was full disclosure of negligently caused therapeutic errors resulted in only one patient thereafter seeking legal advice.¹⁷² In the same study, patients paradoxically acknowledged, “It is realistic to expect that doctors will make errors … Patients have a right to expect that their doctors will not make errors.” Nonetheless, virtually all patients concluded, “Patients should be able to trust their doctors to give them the right care.” As noted earlier, apologetic expressions of sorrow or empathy for a patient’s injuries are barred in evidence from being construed as admissions of fault in 29 states.¹⁴⁸ Protecting the patient’s best interest includes telling the patient when negligent errors occur.

Periodontal Examination

Competent endodontic treatment begins with adequate diagnostic procedures. An adequate periodontal evaluation must accompany each endodontic diagnosis, which requires a diagnostic radiograph, clinical visualization, mobility recordings, evaluation of the periodontal tissues, and probing for periodontal pockets with a calibrated periodontal probe, particularly in furcation areas.^7,8,173

Although endodontic treatment may be successful, tooth loss may result from progression of any residual, untreated periodontitis. Consequently, periodontal evaluation and prognosis are mandatory so that the patient and clinician can make an informed and intelligent choice about whether to proceed with endodontics, a combination of periodontal and endodontic treatment, or extraction.

Each tooth undergoing endodontic therapy (and adjacent teeth) should be probed with a calibrated periodontal instrument to obtain six measurements per tooth. Pockets of 4 mm or greater should be recorded on the patient’s chart. If no pockets exist, WNL (within normal limits) or a similar abbreviation should be noted. Mobility should also be charted and classified class I, II, or III. Gingival recession, furcations, and mucogingival deficiencies should also be recorded.^7,8

A clinician who treats with endodontic success but ignores loss of periodontal attachment may misdiagnose or fail to appreciate the risk of failure because of poor periodontal prognosis. It bears repeating that the endodontic treating clinician should not assume an adequate periodontal evaluation has been performed by another clinician or the referring clinician. Instead, an independent periodontal evaluation should be done with a calibrated periodontal probe and results recorded before initiating endodontics including noting absence of pockets or within normal limits.

If clinically significant periodontal disease is present, the endodontic treating clinician should consult with the restorative clinician to determine whether the periodontal disease will be properly treated or referred to a periodontist in conjunction with endodontic treatment. A patient should be advised of any compromise of the endodontically treated tooth’s periodontal status to comply with required informed consent disclosure.

Temporomandibular Disorders

Occlusal prematurities can trigger temporomandibular disorders (TMDs) in patients with a prior TMD history, so during or following endodontic therapy for such a patient, it is essential that temporary and final restorations not open the bite or significantly alter existing occlusion.¹⁵⁷ Hyperocclusion is a potential TMD trigger that results from open bite or a contralateral side, particularly when a terminal abutment tooth is taken out of occlusion.

Preoperative and Postoperative Radiographs

Pretreatment, midtreatment, and posttreatment radiographs or digital images are essential for endodontic diagnosis and treatment.

Digital Radiography

Digital radiographic endodontic applications are ever increasing in accuracy.¹¹³ The standard of care does not currently require digital imaging, because traditional silver halide radiographic film is a reasonable alternative. When there is more than one reasonably acceptable practice modality, a clinician who chooses either modality meets the standard of care. Fig. 11-31, A represents a distal open margin on tooth #30 (shown digitally) that is not evident in part B with plain-film radiography.

FIG. 11-31 A, Distal open margin on tooth #30 (shown digitally). B, Distal open margin on tooth #30 not evident with plain-film radiography.

Advertised claims of 80% reduction in radiation with direct digital radiography (rather than film) assume the following^37,113:

A digital x-ray image should never be modified to “enhance” the radiographic appearance of the original image. X-ray modification can be detected; in litigation, it can be devastating to the clinician’s defense.

Periapical (PA) radiography is limited to only two dimensions. Newer 3D imaging systems for dental radiology use x-ray beams that are cone shaped. Cone-beam computed tomography can provide a more nearly accurate diagnosis.^54,97,127 In Fig. 11-32, A-C the PA does not show the transported canal and extent of short fill, which is more evident in the CBCT. Each CBCT scan produces three image views: axial, coronal, and sagittal.

FIG. 11-32 A, Periapical (PA) view, which does not show full extent of transported and short-filled canal. Both deficiencies evident in B and C with cone-beam computed tomography (CBCT). B, CBCT Accuitomo of transported canal. C, CBCT Accuitomo of short-filled canal.

CT scans enable evaluation of the true extent of lesions and their spatial relationship to important anatomic landmarks.⁷³ Fig. 11-33, A-C shows a bifid IANC not apparent on panorexes. CT scans may provide information important for retreatment decisions, especially apical surgery. CBCT^54,163,166 showed significantly more lesions than PA radiography, including expansion of lesions into the maxillary sinus, sinus membrane thickening, and missed canals; 34% of such lesions were missed by PA radiography.^163,166 Artificial bone defects in the antral surface were not detected with PA radiography. Because of overlapping roots, only 1 out of 14 furcation defects in upper molars were seen on PA radiography, but CT scans were able to identify all furcal defects. Second molars proved to be the most difficult for detecting lesions with PA radiography alone. Twenty-three teeth with lesions expanding into the maxillary sinus were detected by CBCT, of which only two teeth were seen with PA radiography. Thirty-five teeth with membrane thickening were identified with CBCT, of which 16 teeth were also detected with PA radiography. Fifteen teeth with missing canals were detected with CBCT, of which only four teeth were identified with PA radiography. In a study that compared the efficacy of PA radiography and CBCT in detecting periapical lesions in maxillary premolars and molars for apical surgery,¹⁶⁶ Lofthag-Hansen showed that 38% of maxillary posterior teeth lesions were undetected by PA radiography, despite the fact that an additional different angulated PA radiograph was taken.¹⁶³ Lesions associated with apices near the sinus floor had a higher probability of being missed with PA than lesions associated with apices located away from or overlapping the sinus floor. Expansion of the lesion into the maxillary sinus, thickening of the sinus membrane, missed canals, and presence of apicomarginal communications diagnosed with CBCT were more frequently detected with CBCT than with PA radiography.¹⁶³

FIG. 11-33 A, Bifid inferior alveolar nerve canal (IANC) visible with cone-beam computed tomography (CBCT). B, Bifid canal visible with CBCT but not shown on panorex. C, Branch of IANC apparent on CBCT but not shown on panorex.

(Courtesy Gurminder Sidhu, DDS, MS.)

Apicomarginal communication is an important predictor for the success rate of apical surgery including evidence of undetected vertical fractures necessitating extraction; 83% of apicomarginal communications were not seen with PA radiography in the Lofthag-Hansen study.

If the radiograph shows a small distance between the periapical lesion and the sinus floor when the bony wall is thin, there is a high probability that an oral antral communication (OAC) can result, unless skillful care avoids sinus penetration during apical surgery. CBCT also allows the clinician to study the topography of the bony defect and assess whether the use of guided tissue membranes would be beneficial. Precise morphometric assessment of osseous relationships to the sinus is often inadequate with periapical radiography. Thus CBCT is invaluable in treatment planning for apical surgery, since 70% of cases studied revealed clinically relevant information not found in PA radiography.¹⁶⁶

The probability of detecting lesions with PA alone was limited for teeth with apices in close contact with the floor of the maxillary sinus, for molars (in particular second molars), and when bone thickness between lesion and sinus was less than or equal to 1 mm. In summary, findings of lesion expansion into the sinus, sinus membrane thickening, missed canals, and presence of apicomarginal defects are more frequently diagnosed with CBCT than PA.^54,166

Dental Fear

Dental fear may result in patients delaying or avoiding dental care. Frequent cancellations and missed appointments are characteristically associated with fearful dental patients. Although it is ordinarily a defense of contributory negligence if patients do not follow a clinician’s treatment recommendations, the patient’s advocate may contend that the defendant clinician negligently failed to diagnose a fearful patient. Fearful patients tend to avoid dental treatment because they believe it may exacerbate a prior traumatic dental experience. Referral to clinicians who specialize in treating fearful patients should be considered to facilitate comprehensive dental treatment and to avoid future emergency endodontic care because of repeatedly cancelled treatment visits.

Dental anxiety and finances are the two most important barriers to patients obtaining regular dental care. Fearful dental patients avoid necessary treatment, delay recalls, and are reluctant to undergo painful procedures. Therefore it is essential that such patients be identified for proper management or referral for fear-reduction therapy. A patient who experiences intense anxiety in the dental chair, together with a history of avoiding dental care, suggests a diagnosis of dental phobia. Fearful dental patients fear loss of control during clinical treatment and require reassurance and reaffirmation that they have the power to halt the procedure by raising a hand or using another appropriate gesture. After trust is gained, additional procedures may be performed.

In addition to desensitizing techniques, the use of proven topical-anesthesia delivery systems helps to ensure a relatively painless injection of local anesthetics. Topical-anesthetic patches and oral-anesthetic rinses may prove a valuable aid for pain management of the fearful patient.

The use of psychologic questionnaires, such as the Dental Anxiety Scale or the Modified Dental Anxiety Scale, may be helpful in identifying such individuals.¹²⁵ These simple questionnaires are short, quick, and easy to complete, and users are provided with cutoff scores that help the clinician identify patients who have psychologic special needs. In this way, the clinician will be in a position to assist the dentally anxious or dentally phobic patient in accessing dental health care.

Patient Rapport

Good patient relations are 15% dependent on the clinician’s competency to cure and 85% dependent on the clinician’s ability to assure the patient that the treatment being given will be done with the clinician’s best judgment and care.

Rapport between clinician and patient reduces the likelihood the patient will sue, despite an adverse result. The clinician can develop rapport by demonstrating genuine interest in the patient and making the patient feel valued. Patients feel important if they are seated in the operatory within a reasonable time after arriving. The longer a patient is kept waiting, the more frustration and animosity build. If the patient cannot be seen within a reasonable time, a staff member should communicate the reason and, if appropriate, offer to reschedule the appointment. Staff or the clinician should telephone the patient at the end of the day after any difficult procedure or surgery to check on the patient’s status and remind the patient to follow postoperative instructions. The clinician should record any patient complaints, symptoms, and noncompliance with instructions. The latter can be used as evidence of patient contributory negligence if litigation occurs.

The clinician should remember that the patient lacks the information and expertise to evaluate quality and performance. Patients have their own experiences and perceptions and often rely on lay information when gathering facts about dental procedures and treatment options. However, clinicians should expect some patients (especially those with access to the Internet) to ask technical questions and expect sophisticated responses.

Fees

Clinicians should clarify fees and payment procedures before initiating treatment. If the dental treatment becomes more extensive than originally planned, the clinician should discuss any increased charges and reasons for those charges with the patient before continuing treatment. Charging for untoward complications, such as extended postoperative visits or retrieving broken instruments, should be resisted.

An overzealous receptionist who places payment pressure on a dissatisfied patient, or a clinician who sues to collect a fee from an already displeased patient, may invite a countersuit for malpractice. Refunding fees or paying for the treatment fee of the subsequent treating clinician is usually much less expensive than 1 week in court and a jury award for a patient’s pain and suffering. If clinicians must sue for a fee, they should do so only if treatment is beyond reproach and records substantiate proper diagnosis, treatment, and informed consent options.

Suing for unpaid fees continues to be a proven method for getting countersued for dental malpractice. The client who has paid fees in the past but who stops at some point is either unhappy with the dental service received or short of funds. Dealing with a patient’s countersuit takes time, and collection of unpaid fees may prove difficult. The patient being sued may seek an attorney to scrutinize the clinician’s records for a potential cross-complaint suit against the clinician who initiated the lawsuit for fee collection.

Some cross-complaints for dental malpractice lack merit, whereas others have genuine merit. Pain, suffering, and lost wages may provide a larger potential patient recovery amount than the clinician’s fees in dispute. Whenever possible, clinicians should avoid suing patients for unpaid fees. Before considering suing, the clinician should discuss the fee situation with the patient and consider a payment schedule, fee reduction, or fee waiver.

The amount of money being awarded by juries is increasing. In 1999, a New York City jury awarded $3.5 million against a clinician who had replaced three amalgams with composites. To relieve postoperative sensitivity, endodontics was performed and subsequently failed. Chronic TMD followed the extraction, from which the patient was likely to suffer lifetime pain. In Michigan, two endodontists were disciplined in 2008 for sedation overdose after settling for $3.5 million.²²⁴ In 2008, a Spokane, Washington, jury awarded $14.2 million for unnecessary TMJ surgery. In Fig. 11-34, a Los Angeles jury awarded $1.7 million against a periodontist who “harpooned” the IANC with his implant.

FIG. 11-34 Implant “harpooned” the inferior alveolar nerve canal.

Incidence of Negligence

Medical errors or adverse events are estimated to occur in almost one out of four patient visits to a family practitioner.²¹⁸ A U.S. government study of the Institute of Medicine found that 152,000 avoidable deaths occur annually because of medical negligence.^93,95 In this government study, injury from medical care occurred in 3.7% of hospital admissions. Some 58% of these injuries were concluded to be preventable, and 13.6% were fatal injuries. The actual fatality numbers may be underestimated, since calculations were based solely on hospital chart review.

Alcohol

Excessive alcohol consumption can contribute to a higher incidence of restoration corrosion from chronic regurgitation and vomiting from gastritis associated with alcohol abuse.¹¹⁰ Corrosion can lead to coronal marginal leakage predisposing to endodontic failure. Accordingly, medical histories should include histories of gastric reflux disease, bulimia with associated habitual vomiting, gastritis, and excessive alcohol intake.

Post Perforation

Post selection is important for minimizing the risk of perforations. Generally, posts should not exceed one-third of the mesiodistal width of a tooth, should follow the canal anatomy, and should leave 4 to 5 mm for sealant in the opened post space; this is described more thoroughly in Chapter 23. When a tooth is already crowned, access to the root canal entrance surface should be located before rubber dam placement. This will aid in orienting the root’s long axis, which may vary from the prosthetic crown’s long axis. Fig. 11-35, A-B represents an endodontist’s perforation of tooth #7 because of difficulty locating the entrance into the root canal apical to the pulp chamber.⁸² Fig. 11-36 shows a general clinician’s misaligned post and perforation of tooth #5.

FIG. 11-35 Avoidable perforation.

(Courtesy Stephen Cohen, MA, DDS.)

FIG. 11-36 Post perforation of tooth #5.

Ordinarily, a careful clinician performing endodontic therapy should be able to avoid post perforations. If post perforation occurs, early diagnosis and treatment are important. Belated diagnosis and treatment substantially increase the risk of endodontic failure. If perforation is relatively small in size (i.e., 1 mm or less) and promptly diagnosed at the time of the post perforation, immediate treatment with intracanal sealants (MTA) in the area of the perforation will probably succeed. However, delayed diagnosis and treatment (beyond 24 to 72 hours) result in bacterial contamination in the area surrounding the perforation. Delayed perforation repair therapy can cause periodontal or endodontic lesions and lateral periodontal abscesses occurring secondary to delayed diagnosis, which usually prognosticates a high failure risk.

Perforation Prevention

Irreversible endodontic complication such as furcation perforation during pulpal chamber access is usually preventable with due care.¹⁸⁹ Furcation perforations are avoided by adhering to basic principles of pulpal chamber removal such as cleaning and shaping in a coronal rather than an apical direction. Innovative bur designs can access the pulp chamber without risking furcation perforation by preventing cutting or ditching of the pulp chamber by use of a non–end-cutting bur.⁶⁵

Bleach Injury

Because of the varying shapes of the root canal system in the apical third after cleaning, shaping, and obturation, some residual bacteria may remain, which are entombed. Irrigation with sodium hypochlorite is the usual disinfectant irrigant to minimize these remaining bacteria.²¹⁷ Apical or lateral extrusion occurs when bleach is extruded past the protective apical constriction or through a root perforation. The common denominators of bleach injuries are sudden severe pain and facial swelling.* Because of the clinician’s concern for emergency treatment and the patient’s pain, further endodontic therapy is deferred and usually not completed at the same visit. However, two cases report that compaction was completed the same visit, despite a bleach injury.^177,223 One article reports that subsequent flare-up may be related to the original bleach injury.³⁶

Prevention of bleach extrusion is done with bleach syringes with safe, side-venting needles constantly moving to prevent hydrostatic pressure buildup from bleach fluid. Sodium hypochlorite is extruded into the periapical tissues during root canal therapy if excessive pressure is placed on the irrigating syringe, resulting in an expression of sodium hypochlorite beyond the apex. Subsequent pain is caused by the solution diffusing into the surrounding bone and soft tissue, causing swelling, tissue necrosis, and paresthesia. Surgery is usually contraindicated, and palliative treatment such as cold compresses accompanied by reassurance that most symptoms will dissipate is usually adequate.¹⁵¹ However, if the bleach diffuses into vital nerve tissue of the infraorbital or inferior alveolar nerves, permanent paresthesia and occasional dysesthesia may result.^{75,176,201,271} Figs. 11-37 and 11-38, A-C represent bleach injuries secondary to a root canal perforation. Paresthesia persists. Note the PA does not show the perforation, but the Accuitomo does.

FIG. 11-37 Bleach injury.

FIG. 11-38 A, Periapical tooth #19 showing fractured file but no perforation. B, Accuitomo cone-beam computed tomography (CBCT) showing perforation on the lingual side above the tooth #19 furcation. Perforation not evident in periapical view. Image demonstrates Accuitomo accuracy. C, Bleach extrusion through tooth #19 perforation, with resultant slough of lingual tissue.

Cores

Incorrect choice of cores can contribute to failure, including fractures. Some manufacturers (e.g., ESPE Premier, Norristown, PA, for Ketac silver) recommend against use of their core material unless at least two-thirds of the tooth remains before buildup. Failure to follow the manufacturer’s directions can be considered when an expert determines whether the standard of care was met.

Resin-reinforced post-and-core systems show promise for structurally weakened incisors, but long-term longevity has not been reported. A ferrule or other counter-rotational core design is an important consideration for fracture resistance and retention,¹²⁶ although it has not been proved as statistically significant for the resin-reinforced core systems.²²⁵

Absorbable Hemostatic Agents

Absorbable collagen hemostatic agents should not be placed on or adjacent to peripheral nerves because of the potential for neural injuries, particularly in bony nerve canals.^80,162 Also, as such material is absorbed, its chemotactic properties promote collagen formation and scarring. Compression injuries of peripheral nerves in bony canals can result from expanding scar tissue. FDA adverse incident reports list 11 patients with severe neural defects, including paraplegia secondary to absorbable collagen products placed in the spinal canal for hemorrhage control. Thus the FDA warned of paralysis from absorbable hemostatic agents.^80,162 Accordingly, after hemorrhage is controlled with hemostatic agents, absorbable collagen agents should not be left in situ or near bony neural spaces. This will avoid having remaining hemostatic material cause swelling, pressure, or migration to adjacent neural tissues. The minimum amount of collagen agents necessary to achieve hemostasis should be used.

Pneumomediastinum (Air Embolus)

When performing endodontic surgery, a surgical handpiece should be used that ventilates air through the back of the handpiece rather than an air turbine that directs air into open tissue spaces. Pneumomediastinum, also known as mediastinal emphysema, may result from air embolisms dissecting down the neck facial planes from air forced into the submandibular or sublingual spaces contiguous with neck spaces.^27,243

Broken Needle

Scanning electron microscopy (SEM) with an energy-dispersive x-ray spectrometer attachment can analyze whether a broken instrument is due to excessive operator trauma or manufacturing defect. Fig. 11-39 represents a combination of low-cycle bending fatigue and tensile overload. Accordingly, the local anesthetic needle likely fractured because of bending deformation as it struck the ramus.

FIG. 11-39 Tensile overload shown in elongated ductile dimple voids.

Ductile rupture in metals results from shearing along planes that are oriented at 45 degrees to the tensile stress. Tensile “necking” results from multiple slipping deformations in all the 45-degree planes to the needle axis because of significant overload. Final rupture results from a combination of bending and tension. Fig. 11-40 shows the needle tip bent and blunted as it hit a hard object. No manufacturing defects were found. Fig. 11-41, A-B shows SEM views of the fracture. Fig. 11-41, C is a SEM view of the needle fracture taken at the hub side of the fracture. These illustrations demonstrate why longer 25-gauge needles should be used for mandibular blocks rather than shorter 30-gauge needles.¹⁶⁹

FIG. 11-40 Needle blunting of broken needle tip demonstrating striking hard object (ramus).

FIG. 11-41 A, Needle fracture with scanning electron microscopy (SEM). B, Needle fracture, side view (SEM). C, Needle fracture at high SEM magnification.

Sterilization

Nonsurgical use of the dental unit water supply should comply with the Environmental Protection Agency regulatory standard of less than 500 colony-forming units (CFU)/ml.

CDC guidelines require sterile water or sterile solutions for all surgical procedures.¹⁵² Disinfected water from handpieces or ultrasonic devices is no longer acceptable as a water coolant during surgery. Instead, an ultrasonic device that can deliver a sterile irrigant during surgery should be used. Dental unit water lines are available with tubing that can be disposed or autoclaved for surgery. Some ultrasonic devices are also available with disposable tubing to maintain a sterile water coolant delivery system.

Digital radiographic devices that contact the oral mucosa region require a combination of barrier protective sheath and chemical disinfection in accordance with prudent manufacturers’ directions.¹²²

Rotary NiTi files likely contain bioburden material that after sterilization may act as a foreign body. Efficiency degradation after sterilization should suggest to the prudent clinician a single-use philosophy.¹⁹

Avoiding the Inferior Alveolar Nerve Canal

When placing implants or performing apicoectomies in close proximity to the mental foramen in the bicuspid region, the clinician should consider the anterior loop of the IAN, which usually ascends as it approaches the mental foramen, compared with the IAN’s more inferior location in the molar region (Fig.11-42, A-C¹⁰⁹; this Los Angeles case settled for $915,000, with permanent dysesthesia). The IANC varies from buccal to lingual as it courses the length of the mandible. Thus, CBCT imaging aids in assessing the IANC location for planning implant placement or apical surgery.^54,73

FIG. 11-42 A, Illustration showing implant placed into ascending inferior alveolar nerve canal (IANC). B, Cone-beam computed tomography (CBCT) image of implant into ascending IANC. Settlement of $915,000. C, Implant into IANC; immediate postoperative Panorex image. Same patient but with CBCT image.

Mental Nerve

The mental nerve, as the terminal branch of the IAN, is at risk during elevation of the mandibular mucoperiosteum. Careful flap design and elevation are important to avoid mental nerve injury while working on the buccal surface of the mandible in the region of the mental foramen.¹⁶⁹ In performing incision and drainage in the region of the mental foramen, a diagnostically accurate radiograph is necessary to avoid incising through the course of the mental nerve.^63,146

Medication Errors

The FDA has received over 95,000 reports of medication errors since the year 2000. Medication errors involve the wrong drug, an extra or wrong dose, omission of a drug, or administering a drug by the wrong route or at an incorrect time.¹⁵³

Medication errors are often preventable.²⁴⁷ Two major sources of errors in prescribing are poor penmanship and the use of error-prone abbreviations. Writing “1.0 mg” can be read as “10 mg” if the decimal point is not clearly visible. The FDA recommends that no trailing zeros be used when denoting doses expressed as whole numbers, and that preceding zeros be used whenever a decimal point is needed for a dose that must be administered as a fraction of a whole number (e.g., 1 mg; 0.5 mg). Recent drug label changes can be readily accessed on the National Library of Medicine’s DailyMed website.

Posttrauma Therapy

The reader is referred to Chapter 17 for a full discussion of how to treat and manage patients who have sustained a traumatic injury.

Continuing Education

A clinician is legally obligated to maintain current knowledge in the field of endodontics. If not, the clinician may have only 1 year of knowledge (repeated 30 times) during the span of a 30-year career. By not maintaining continuing education knowledge and updating clinical skills, a clinician may unreasonably condemn otherwise salvageable teeth because of inadequate diagnosis or treatment.

Millennium Management of Endodontic Advances

Technologic advances are touted as ideal endodontics. However, the standard of care is a minimal standard of reasonably acceptable practice rather than the perfect ideal. The reasonable and prudent clinician is not required to know and use all the latest technologic advances in endodontics. On the other hand, the reasonable and prudent clinician must keep current with available advances that are generally accepted and proved by research. Microsurgical endodontics is an example of improved endodontics technology; use of magnifying loupes or similar devices may prove inadequate for apical surgery or fractured instrument retrieval compared with microscopes. Therefore the clinician should adopt proven improvements in the endodontic field. Three-dimensional reconstruction of mandibles can be accomplished with cone-beam volumetric tomography to accurately locate the IAN or mental foramen. Fig. 11-43 shows an example of volumetric tomography usage for implant placement and/or apical surgery.

FIG. 11-43 Cone-beam computed tomography usage for implant placement and/or apical surgery.

If studies demonstrate significantly superior results for some alternative to surgical endodontics, the informed consent standard of care may require that the patient be advised of the alternative technique, even if it is more expensive. There may be more than one path to success. So long as the clinician uses reasonably acceptable techniques and informs the patient of reasonable alternatives, the standard of care is met, but clinicians should remember that today’s surgical advance may be tomorrow’s retreat. For example, temporomandibular joint (TMJ) implants were inadequately tested technology on loading joints and proved virtually 100% disastrous.^77,209 Microscopic apical surgery has gained general acceptance, is performed by the majority of endodontists, and represents the current standard of care.^55,136,149

Clinicians should evaluate the quality of peer-reviewed research articles for new products rather than accepting them at face value. A case report amounts to no more than the author’s personal experience with one patient. Some authors report a “series” of patients if there are only two patients. A brash conclusion is to state something has occurred time and time again if similar findings were observed with only three patients. Valid scientific principles mandate that a test result can be replicated by other competent scientists duplicating a particular research protocol. If research cannot be duplicated, sweeping conclusions should not be made. Comparative effectiveness studies should demonstrate not only better results than a placebo but also relatively better results compared with similar marketed products tested under similar clinical conditions.

Statistical Research

Statistical research conclusions may vary, since research protocols may not similarly control variables of population groups studied.^108,205 Discrepancies occur even within trials or among large trials. Meta-analyses of multicenter randomized controlled trials aim to reduce bias by estimating the effect size for outcomes and adverse effects after pooling all qualified research studies. This approach will not assist if the supporting randomized controlled trials are derived from confounded data from heterogeneous trials. Such research results represent an estimate of the average difference in the responses of the tested treatment groups. These differences in results of different centers from various test groups may reflect important distinctions in the clinical conditions of enrolled research subjects. Such distinctions may help identify subgroups of patients harmed by the researched product, although on average, treatment has an overall benefit.¹²⁴

Since most research is currently controlled and sponsored by companies marketing a product, only favorable studies are usually submitted for publication. Literature reviews are prone to publication bias because journal editors are more likely to publish favorable rather than unfavorable conclusions. The most important use of literature review articles is to develop research questions that ultimately must be tested using a randomized controlled trial. Studies other than randomized controlled trials were the basis for prescribing hormone replacement therapy to millions of women to prevent cardiovascular disease. A randomized controlled trial of this therapy was terminated early because increases in cardiovascular disease and breast cancer were discovered.

Before the 1980s, pharmaceutical industry grants to academic institutions to fund studies by faculty members gave investigators total responsibility to design the study, analyze and interpret the data, write the papers, and decide where and how to report the results. Neither the investigator nor their institutions had other financial connections to sponsoring companies. Drug companies now finance most clinical research on prescription drugs. There is mounting evidence that research is skewed to make drugs look better and safer than research findings warrant.*

Negative results are often not published. For example, a study of 74 clinical trials of antidepressants found that 37 of 38 positive studies were published. Conversely, of 36 negative studies, 33 were either not published or published in a form that conveyed a positive outcome.²⁵⁴

Published clinical research is too often biased, usually by designing the studies in ways that will almost inevitably yield favorable results for the sponsor.^178,272 For example, comparator drugs may be administered at a too-low dose so that the sponsor’s drug looks more effective, or at a too-high dose so that the sponsor’s drug has relatively fewer adverse effects. Bias also takes the form of comparing a new drug with a placebo when the relevant research question is how it compares with an existing drug. A fair comparison would compare the new drug with an older FDA-approved drug at equivalent doses. As the former editor for 2 decades of the New England Journal of Medicine concluded in a 2008 JAMA article, “It is naive to assume bias is only a matter of a few isolated instances. It permeates the entire system. Physicians can no longer rely on the medical literature for valid and reliable information.”¹⁴

Prudent clinicians do not adopt every new technology. Before adoption, such technology must have demonstrated benefits with acceptable levels of risk. It must also be adequately tested, with sufficient numbers of test subjects, over a significant length of time. Because manufacturers too often rush their products to market, newer products may not meet this criterion. Therefore, except for breakthrough technologic changes, a clinician will not likely be judged negligent for failure to adopt each latest device or technique. However, clinicians must keep in mind that in the information technology industry, 1 year is considered several generations, if not an eternity.^30,98 In general do not be the first nor the last to adopt improved technology.

The standard of care usually does not mandate incorporation of every new technology. However, in those states with informed consent laws that are based on what a prudent patient would want to know rather than what prudent clinicians should do, the patient may argue that an alternative technology or technique used by a different clinician would have been chosen had the clinician provided the patient with such information. Microscopic endodontics for broken file retrieval and CBCT to aid apical surgeries are pertinent examples.^54,127

Other Clinicians’ Substandard Treatment

Clinicians should not be overly protective of blatant examples of another clinician’s substandard dental treatment. On discovery of apparent negligent treatment by a previous clinician, the clinician should consider investigation. Begin by obtaining the patient’s written authorization for transfer of a copy of the previous clinician’s records, including radiographs. If negligence is still suspected after reviewing the records, the clinician should consider talking with the previous clinician to learn the circumstances of what occurred during the patient’s past treatment (after obtaining the patient’s consent pursuant to HIPAA).

On discovery of a gross violation of the standard of care, a clinician has an ethical responsibility to report the matter to the local dental society, peer review, dental licensing board, or agency.^10,97 If the patient is misinformed and later discovers patently obvious negligent treatment, the subsequent clinician could arguably be sued as a co-conspirator to fraudulent concealment of the prior clinician’s neglect.

Peer Review

If despite good rapport, candid disclosure, and an offer to pay corrective medical or surgical bills the patient is still unsatisfied, the clinician should consider referring the patient to peer review. Peer-review committees award damages for out-of-pocket losses but not for pain and suffering or lost wages. Consequently, even if the committee’s decision is adverse to the clinician, the damage award will probably be less than a jury’s verdict. If peer review finds for the clinician, the patient may be discouraged from proceeding further with litigation. Peer review proceedings, including the committee’s decision, are not admissible in court.⁴³ Insurance carriers usually honor and pay a peer-review committee award, because a fair adjudication of the merits has been determined; the award is usually less than a jury would award. Defense costs, including attorney’s fees, are saved with peer review.

Human Immunodeficiency Virus and Endodontics

A clinician may not ethically refuse to treat an HIV-seropositive patient solely because of such diagnosis.⁶⁰ Although in the 1980s, no federal law had clearly extended the protection of the handicapped laws to patients with AIDS, federal congressional action in 1990 extended this protection to the dental office setting with the passage of the Americans with Disabilities Act.¹² Many states already offer additional protection under state law.^40,62

Confidentiality for patients disclosing their HIV status is important. An inadvertent disclosure to an insurance carrier or to other third parties without any need to know may result in cancellation of the patient’s health, disability, or life insurance. This cancellation could result in a claim against the clinician whose office disclosed such information without authorization. Therefore, employees should sign the confidentiality agreement shown in Fig. 11-44. In signing this agreement, the staff may be alerted to the seriousness and importance of maintaining the confidentiality of patient health histories, because these histories may document AIDS, venereal disease, or other socially stigmatizing diseases.

FIG. 11-44 Dental auxiliary confidentiality agreement.

If a patient requests that the clinician not inform the staff of his or her HIV status, the clinician should refuse to treat that patient. This information is essential to staff members who may come in contact with the infection. An accidental needle stick with HIV-infected blood, which carries a risk of approximately 1 in 250 chances of seroconversion, may occur. Current medical protocol includes prophylactic administration of zidovudine (AZT), either to prevent or to slow the manifestation of AIDS from a deep, penetrating, accidental needle-stick exposure.

Although a treating clinician risks devastating a dental practice by informing patients that the clinician has contracted AIDS, the legal risk of not informing patients is much greater. The health care provider may be required to advise patients of positive HIV test results under the doctrine of informed consent (i.e., advising of a known risk of harm from accidental exposure).⁶⁶ Even if an uninformed patient never contracts AIDS, in those states that use a reasonable patient standard for disclosure of material risks of treatment (which could include accidental direct contact such as an unintended cut or needle stick), the patient may decide to bring an action for intentional concealment as a variant of informed consent and seek to recover emotional distress and punitive damages. Conversely, patients may be legally liable for intentionally misrepresenting their health history regarding their HIV status.³⁵

Infective Endocarditis

If a patient’s medical history shows valvular heart defects with regurgitation, the clinician should consult with the patient’s physician to determine the necessity of antibiotic prophylaxis against infective endocarditis in accordance with current American Heart Association (AHA) guidelines.²⁶⁹ If the physician does not appear knowledgeable about those guidelines, the clinician should provide a copy of the guidelines to the physician. If the physician advises deviation from AHA guidelines, the clinician should inquire why the physician feels that this is appropriate. The clinician should also record any discussions with the physician in the patient’s chart and confirm the discussion and the physician’s recommendation in writing (by fax and letter to the physician).

Communications with the physician should be specific, because dental treatment risks, such as overextension of files or filling material sealants that occur nonsurgically and may enter the bloodstream, may not be fully understood. A sample format is shown in Fig. 11-45.

FIG. 11-45 Sample of written physician recommendations.

Individuals who have undergone total joint-replacement surgery may arguably be at increased risk for bacterial infection to the artificial joint. Late joint infections (i.e., less than 6 months) may potentially occur as the result of bacteria introduced into the oral cavity. Antibiotic prophylaxis may be recommended for certain individuals with total joint replacements before specific dental procedures (as recommended by the AHA). The drugs (e.g., cephalexin, cephradine, amoxicillin) used to prevent the late infection of prosthetic joints differ slightly from those recommended by the AHA.^6,133 The treating orthopedist’s recommendation is the guidepost clinicians should consider during the first 6 months after joint replacement surgery.