Extrinsic Tooth Stains

Extrinsic stains can be caused by smoking cigarettes, marijuana, cigars, or pipes; using spit (smokeless) tobacco; and rinsing with antimicrobial agents with substantivity such as chlorhexidine or cetylpyridinium chloride. Other common sources of stains include artificial and natural dyes in foods and beverages (e.g., tea, coffee, cola beverages, red wine, berries), iron tablets, chromogenic bacteria in oral biofilm, and poor oral hygiene. Teeth also may become stained from environmental factors such as metallic dust in industrial employment settings (see Chapter 15). Extrinsic stains usually can be removed by scaling with hand-activated, sonic, and ultrasonic instruments and by rubber-cup or air polishing.

Intrinsic Tooth Stains

Intrinsic stains may be hereditary, developmental in nature, or associated with aging. Defects in enamel or dentin during tooth development resulting from high fevers, trauma, excessive intake of fluoride, or tetracycline medication may result in permanently mottled or stained tooth structure (Figure 27-1, A). Tooth enamel effects may range from barely noticeable pitting to gross enamel discoloration and defects that fracture easily. Color changes may be slight or severe, including yellow, light to dark brown, blue-gray, and black. Given the translucence of enamel, intrinsic stains may occur adjacent to large restorations, pulpal necrosis, and dental caries (see Chapter 15).

Figure 27-1 A, Intrinsic staining from dental fluorosis. B, Brown and yellow extrinsic stain.

(Courtesy Dr. Frank Hodges.)

Cleansing and Polishing Agents for Managing Extrinsic Stains

Agents used to clean and polish teeth, restored tooth surfaces, and dental appliances contain abrasive agents (see Chapter 23, Figure 23-5). Abrasive agents are composed of natural or synthetic materials that vary in hardness, particle shape, and particle size (grit). These agents are commonly used in both clinical and laboratory procedures and added to dentifrices, prophylaxis pastes, abrasive strips, and polishing discs. Fine grit abrasive agents are used for cleaning and polishing tooth enamel, whereas fine, medium, and coarse grit abrasives are used to polish dental appliances in the laboratory. A very hard abrasive can produce minimal abrasion if its particle size is very fine to superfine.

Abrasives found in dentifrices (e.g., calcium pyrophosphate, dibasic calcium phosphate dehydrate, tricalcium phosphate, hydrated alumina, hydrated silica, sodium metaphosphate) should have extremely low abrasiveness because toothpastes are used for daily cleaning. Abrasives found in prophylaxis pastes (superfine pumice, silicon dioxide, zirconium silicate, calcium carbonate) have a low to moderate abrasiveness to facilitate extrinsic stain removal and polish teeth. Abrasives used in the laboratory and to contour some restorations (rouge, tripoli, cuttle, garnet, emery) may have low, moderate, or high abrasiveness. Abrasive agents used in the mouth must produce a smooth, clean, lustrous surface with minimal scratches because polished tooth surfaces are more resistant to the accumulation of extrinsic stain and calculus.

Natural abrasives include Arkansas stone, chalk, cuttle, kieselguhr, corundum, pumice, emery, garnet, quartz, sand, tripoli, zirconium silicate, and diamond. Synthetic abrasives include aluminum oxide, tin oxide, silicon carbide, synthetic diamond, and rouge. Common abrasives are listed in Table 27-1. Dental substrates are listed in Table 27-2.

TABLE 27-1 Abrasives Used in Dental Hygiene Practice

∗ Mohs Hardness Value: standard for the hardness of abrasives and substrates; the higher the value, the harder or more abrasive the material. For comparison, cementum is 2 to 3, dentin is 3 to 4, and enamel or apatite is 5 to 6. Even a very hard material will be minimally abrasive if used with a very fine particle size.

TABLE 27-2 Hardness Values for Dental Substrates

For extrinsic tooth stain removal or the polishing of a restorative material to be achieved, an abrasive agent is applied against the surface to abrade the stain away and/or create a surface with a high luster. The following key characteristics of the abrasive agent affect the size of the surface scratches and the polishing outcome:

Hardness determines whether one abrasive material can scratch the surface of another material. Hardness is assessed using the Mohs Hardness Scale, which ranges from 1 (lowest hardness material) to 10 (highest hardness material). To polish, particles must be 1 to 2 units on the scale harder than the surface being polished. Cleansing a surface requires a material that is less than or equal to that of the surface being cleaned in order to prevent scratching.

Particle shape of an abrasive may be angular, blocky, semiround, or round. Sharp angular edges deepen the scratches on the surface being polished.

Particle size (also known as grit) affects cleaning rate and scratch pattern produced on a surface. Fine grit yields the least amount of surface abrasion even if the abrasive material is high on the Mohs Hardness Scale, whereas coarse grit, the most abrasive, can scratch and roughen surfaces, making them more likely to accumulate oral biofilm and stain. There is no industry standard for defining superfine, fine, medium, or coarse grit. The meaning of these labels varies from manufacturer to manufacturer.

Bleaching or Whitening Agents

Although intrinsic stains cannot be removed by traditional professional methods (scaling and selective polishing), they may be managed by tooth bleaching with a chemical oxidizing agent to lighten tooth discolorations or by restorative procedures such as veneers and crowns. Several commonly used oxidizing agents found both in professionally applied, professionally dispensed and in over-the-counter (OTC) products include hydrogen peroxide, carbamide peroxide, or papain (an enzyme from papaya fruit) as the active ingredient. A whitening product containing 10% carbamide peroxide is equivalent to another product that contains 3.3% hydrogen peroxide. Recognition of intrinsic staining and referral for appropriate treatment address the client’s human need for a wholesome facial image. Intrinsic tooth stain severity usually determines which stain management method is recommended, and these are discussed later in this chapter.

Rubber-Cup Polishing

Rubber-cup polishing is the removal of extrinsic tooth stains after scaling using a low-speed dental handpiece, a prophylaxis angle with rubber cup and bristle brush, and prophylaxis paste or other cleaning or polishing agent. This traditional method is effective for removal of extrinsic tooth stains, has good client acceptance, and is easy to learn and perform. Five variables influence efficiency, effectiveness, and tooth structure loss during extrinsic tooth stain removal with a rubber cup:

Abrasiveness of the prophylaxis paste (or other abrasive agent) used during the procedure: The harder the abrasive, the greater the rate of abrasion. Always use the least abrasive agent to accomplish stain removal.

Quantity of abrasive agent: The greater the amount of abrasive particles applied, the greater the rate of abrasion. Abrasive agent particles should be suspended in a lubricating vehicle such as water or humectants to decrease both quantity of abrasive particles and frictional heat generated by the procedure. Never use a dry abrasive agent on tooth enamel. Always use wet abrasive agents.

Contact time of the rubber cup or bristle brush on the tooth surface: The longer the contact time, the greater the rate of abrasion and frictional heat. Always use short, intermittent contact between rubber cup and the tooth or restorative materials.

Speed or revolutions per minute (rpm) of the rubber cup or bristle brush: The greater the speed of the rotating rubber cup, the greater the rate of abrasion and frictional heat generated. Always use low speeds no greater than 3000 rpm.

Applied pressure or force of the rubber cup or bristle brush on the tooth surface: The greater the force applied to the rubber cup against the tooth, the greater the rate of abrasion and frictional heat generated. Always use a light intermittent (staccato) touch.

To preserve tooth structure and prevent damage to teeth and restorative materials, the practitioner starts with the least abrasive agent and amount of agent, with the least amount of contact time, at the lowest speed, and with the least amount of pressure to remove the extrinsic stain and to avoid tooth surface damage. The clinician can always increase any of these variables if necessary to achieve the desired clinical outcome.

Risk Management Strategies for Rubber-Cup Polishing

Because of the adverse effects discussed in the preceding section, contraindications to rubber-cup polishing exist (Box 27-1). After scaling and root planing, stains and biofilm on teeth can be removed during hand-activated and mechanized scaling; biofilm can also be removed mechanically using a toothbrush and interdental aids. When stains remain after scaling, selective polishing is indicated.

Armamentarium for Rubber-Cup Polishing

Prophylaxis Paste (Figure 27-2, A)

Abrasives used in polishing agents (e.g., prophylaxis pastes) are applied selectively based on amount and type of extrinsic stain, and whether the surface to be polished is tooth or restored surface. Prophylaxis pastes are pleasantly flavored and may contain active ingredients to prevent dental caries (fluoride), enhance tooth smoothness and enamel luster (e.g., amorphous calcium phosphate [ACP], casein phosphopeptides [CPP-ACP]), improve tooth whiteness (e.g., hydrogen peroxide), or decrease tooth sensitivity (e.g., fluoride, arginine bicarbonate, CPP-ACP, ACP, bicarbonate or carbonate). Types of prophylaxis pastes are:

Fluoride-containing prophylaxis paste (Nupro)

○ May contain 4000 to 20,000 ppm fluoride ion, so client must not swallow the paste

○ Replaces some of the fluoride lost by the abrasive action of the polishing procedure

○ Not a substitute for professionally applied fluoride therapy

ACP-containing prophylaxis paste (Enamel Pro with ACP)

○ Combines with fluoride and tooth structure to form apatite

○ May seal exposed dentinal tubules; may reduce dentinal hypersensitivity

○ May enhance tooth smoothness and luster of the enamel

○ More research needed

CPP-ACP–containing paste (MI Paste)

○ Combines with fluoride and tooth structure to form apatite

○ May enhance tooth smoothness and luster of the enamel

○ Promotes remineralization

○ May seal exposed dentinal tubules; may reduce dentinal hypersensitivity

○ Can also be applied with a finger or custom mouth tray

○ Not to be used if client has a casein allergy; can be used in clients who are lactose intolerant

○ More research needed

Hydrogen peroxide–containing prophylaxis paste (Natural Elegance)

○ May contain up to 35% hydrogen peroxide to provide a whitening benefit

○ Hydrogen peroxide gel can be polished into the tooth surface with a rubber cup and prophylaxis paste

○ Best for maintaining tooth whitening, rather than as a tooth whitening protocol

○ More research needed

Arginine bicarbonate, calcium, bicarbonate or carbonate-containing prophylaxis paste (ProClude)

○ May seal exposed dentinal tubules; may reduce dentinal hypersensitivity

○ More research needed

NovaMin-containing prophylaxis paste (with calcium, phosphorus, sodium and silica) (NuCare Prophy Paste)

○ May seal exposed dentinal tubules; may reduce dentinal hypersensitivity

○ More research needed

Figure 27-2 A, Examples of commercial prophylaxis pastes in unit doses. B, Low-speed handpieces.

(Courtesy DENTSPLY Preventive Care Division, York, Pennsylvania.)

Prophylaxis pastes containing microfine white sapphire particles are also marketed to restore the original luster to veneer, composite, gold, and porcelain restorations and can also be used safely on natural teeth (e.g., Soft Shine cosmetic polishing paste). Toothpastes also contain mild abrasives for cleaning with a toothbrush or with a rubber cup and low-speed handpiece. The least abrasive type of paste necessary for stain removal should be used at a low speed with light intermittent pressure.

Prophylaxis Angle and Dental Handpiece (Figure 27-2, B)

A disposable or stainless steel prophylaxis angle attached to a low-speed, ergonomically designed handpiece is used for selective polishing.

The head of the prophylaxis angle will have one of the following:

Rubber cup (screw-type, latch-type, or snap-on or on a disposable prophylaxis angle)—used on all tooth surfaces

Flat or pointed bristle brush (screw-type, latch-type, or snap-on or on a disposable prophylaxis angle)—for stain removal on occlusal surfaces and in fossa (Figure 27-3)

Figure 27-3 A, Metal prophylaxis angle with rubber cup and brush. B, Disposable plastic prophylaxis angles with rubber cup and with brush.

(From Newman MG, Takei HH, Klokkevold PR, Carranza FA: Carranza’s clinical periodontology, ed 10, St Louis, 2006, Saunders.)

Figure 27-4 Handpiece grasp.

Figure 27-5 Overlapping strokes to ensure complete coverage of the tooth as needed.

(From Bird DL, Robinson DS: Torres and Ehrlich modern dental assisting, ed 9, St Louis, 2009, Saunders.)

Figure 27-6 Polishing the buccal surfaces of the maxillary right posterior quadrant.

Figure 27-7 Polishing the facial surfaces of the maxillary anterior teeth.

Figure 27-8 Polishing the buccal surfaces of the maxillary left posterior quadrant.

Figure 27-9 Polishing the lingual surfaces of the maxillary right posterior quadrant.

Figure 27-10 Polishing the lingual surfaces of the maxillary anterior teeth.

Figure 27-11 Polishing the lingual surfaces of the maxillary left posterior quadrant.

Figure 27-12 Polishing the buccal surfaces of the mandibular right posterior quadrant.

Figure 27-13 Polishing the facial surfaces of the mandibular anterior teeth.

Figure 27-14 Polishing the buccal surfaces of the mandibular left posterior quadrant.

Figure 27-15 Polishing the lingual surfaces of the mandibular right posterior quadrant.

Figure 27-16 Polishing the lingual surfaces of the mandibular anterior teeth.

Figure 27-17 Polishing the lingual surfaces of the mandibular left posterior quadrant.

(From Bird DL, Robinson DS: Torres and Ehrlich modern dental assisting, ed 9, St Louis, 2009, Saunders.)

Handpieces and stainless steel prophylaxis angles are cleaned, lubricated, and sterilized according to manufacturers’ directions. Disposable prophylaxis angles are discarded after each use. Materials and procedures for rubber-cup polishing are outlined in Procedure 27-1.

Procedure 27-1 RUBBER-CUP POLISHING

Photographs courtesy Dr. Margaret Walsh, University of California–San Francisco.

EQUIPMENT

Polishing paste, esthetic restoration polishing paste, and low-abrasive toothpaste

Prophylaxis angle and toothbrush

Dental floss or tape

Floss threader (if needed)

Rubber cups and pointed bristle brushes

Low-speed handpiece

Gauze squares

Mouth mirror, air-water syringe

Disclosing solution

Preprocedural antimicrobial mouth rinse

Saliva ejector or high-volume evacuation (HVE) tip

Safety glasses for client

Personal protective equipment (PPE)

STEPS

Preparation and Positioning

1. Evaluate client’s health and pharmacologic history to determine need for antibiotic premedication.

2. Identify tooth surfaces indicated and contraindicated for polishing. Always polish esthetic restorations first, then polish teeth.

3. Educate client about selective polishing procedure.

4. Select polishing abrasive based on type of stain and oral restorations and assemble basic setup (see Figure 27-2, A).

5. Wear appropriate PPE and provide protective eyewear for client.

6. Provide client with a preprocedural antimicrobial rinse polishing.

7. Have client tilt head up and turn slightly away when polishing maxillary and mandibular right buccal surfaces of posterior teeth (left buccal if left-handed practitioner) and maxillary and mandibular left lingual surfaces of posterior teeth (right lingual if left-handed practitioner).

Grasp

8. Use modified pen grasp (Figure 27-4).

9. Rest handpiece in V of hand.

10. Have all fingers in contact as a unit.

Fulcrum

11. Establish intraoral fulcrum close to working area.

12. Fulcrum on ring finger.

13. Use moderate fulcrum pressure.

Adaptation

14. Angle rubber cup to flare at gingival margin.

15. Adapt rubber cup to reach distal, facial and lingual, or mesial surfaces.

16. Adapt cup to tooth by rotating handpiece or pivoting on fulcrum as necessary.

17. Adapt brush to occlusal surface.

Stroke

18. Fill cup with paste and evenly apply to surfaces to be polished.

19. Place cup on tooth; activate handpiece by gently stepping on rheostat. Stroke from the gingival third to the incisal third with just enough pressure to make the cup flare while using wrist-forearm motion to polish the teeth.

20. Use low speed and intermittent, dabbing, overlapping strokes with light to moderate pressure in a cervical to occlusal or incisal direction (Figure 27-5).

21. Remove rubber cup from tooth at completion of stroke; readapt cup for next stroke.

22. Hold mirror in nondominant hand to retract buccal mucosa. Instruct client to close mouth halfway and to tilt head slightly toward the ceiling. Polish buccal surfaces of maxillary right posterior quadrant (Figure 27-6).

23. Polish facial surfaces of maxillary anterior teeth. Palm mirror and retract lip with fingers of nondominant hand (Figure 27-7).

24. Hold mirror in nondominant hand to retract buccal mucosa. Instruct client to close mouth halfway and to tilt head slightly toward the ceiling. Polish buccal surfaces of maxillary left posterior quadrant (Figure 27-8).

25. Polish lingual surfaces of maxillary right posterior quadrant. Use mirror for indirect view and indirect lighting (Figure 27-9).

26. Polish lingual surfaces of maxillary anterior teeth. Use mirror for indirect vision (Figure 27-10).

27. Polish lingual surfaces of maxillary left posterior quadrant. Use mirror for indirect vision (Figure 27-11).

28. Rinse client’s teeth.

29. Hold mirror in nondominant hand to retract right buccal mucosa. Polish buccal surfaces of mandibular right posterior quadrant (Figure 27-12).

30. Palm mirror and retract lip with fingers of nondominant hand. Polish facial surfaces of mandibular anterior teeth (Figure 27-13).

31. Retract buccal mucosa with mirror and polish buccal surfaces of mandibular left posterior quadrant (Figure 27-14).

32. Polish lingual surfaces of mandibular right posterior quadrant. Use mirror to retract tongue and for indirect vision and lighting (Figure 27-15).

33. Polish lingual surfaces of mandibular anterior teeth (Figure 27-16). Use mirror for indirect vision and indirect lighting. Avoid resting mirror on sublingual mucosa.

34. Polish lingual surfaces of mandibular left posterior quadrant (Figure 27-17). Use mirror to retract tongue and for indirect vision and lighting. Replace rubber cup with flat or pointed brush and remove occlusal stain.

35. Floss client’s teeth with abrasive agent still on teeth, then rinse.

36. Apply topical fluoride therapy (see Chapter 31).

37. Document completion of service in client’s record under “Services Rendered” and date the entry—e.g.,”Removed tobacco stain with rubber-cup polishing on No. 6-11L, 22-27L; removed client oral biofilm from remaining teeth with a soft toothbrush and fluoride gel toothpaste. Flossed all teeth. APF topical fluoride gel treatment—tray method—provided for 4 minutes. Advised client not to eat, drink, or rinse for 30 minutes.”

Hand Scaling

Hand-activated instruments such as curets and sickle scalers are designed primarily for calculus removal but can also be used for extrinsic stain removal (see Chapter 24). When stain adheres to calculus, it may be efficiently removed along with the calculus. Because hand-activated instruments are small, they can remove stain in areas inaccessible to a rubber cup (e.g., in an embrasure). Hand-activated instruments are not abrasive to enamel surfaces; however, they can remove cementum on root surfaces, so overinstrumentation should be avoided. When moderate to heavy stain is present on root surfaces, the dental hygienist is faced with the problem of removing the stain with the least alteration of exposed cementum or dentin. Because stain removal is only cosmetic, the client should be informed that stain is not associated with oral disease and will not harm teeth or gingiva if not removed. As much stain as possible should be removed during root planing with curets. The less root structure removed, the less chance of root surface sensitivity after the procedure. At present, any method capable of removing stain from root surfaces might also remove cementum.

Sonic and Ultrasonic Scaling Instruments

Ultrasonic and sonic scaling (see Chapter 25) to remove extrinsic stain has the same advantages and disadvantages as when these processes are used for calculus removal. Efficiency and efficacy are the primary benefits for selecting mechanized instruments for stain removal. In addition, a slender tip is able to remove stain on occlusal surfaces and in areas of rotated or overlapped teeth. There is usually good client acceptance, and operator fatigue is minimized compared with hand-activated instrumentation.When comparing the results of studies on the effects of hand-activated instruments versus sonic and ultrasonic instruments on root surface roughness, the findings are ambiguous. Rough cementum and lost tooth structure are encountered with both types of instruments.

Aerosols are created with sonic and ultrasonic instrumentation and if used improperly can generate heat and cause tissue trauma. Aerosols can be minimized with the use of high-volume evacuation.

Air Polishing

Air polishing is a method of stain removal that uses a specially designed device with a handpiece that delivers a spray of warm water and prophy powder (sodium bicarbonate or aluminum trihydroxide) under pressure (see Figures 27-18 and 27-19). An efficient and effective method of stain removal, the air polisher has the following advantages:

Requires less time than traditional rubber-cup polishing

Removes stain three times as fast as hand scaling.

Creates less operator fatigue

Figure 27-18 Flavored prophy powder for use in air polishing device.

(Courtesy DENTSPLY Preventive Care Division, York, Pennsylvania.)

Figure 27-19 Prophy-Jet and ultrasonic scaler combination.

(Courtesy DENTSPLY Preventive Care Division, York, Pennsylvania.)

Figure 27-20 Recommended angulations of Prophy-Jet nozzle to tooth surface.

(Adapted from DENTSPLY Preventive Care Division, York, Pennsylvania.)

Air-polishing also is recommended for cleaning and removing extrinsic stain from pits and fissures before placement of dental sealants.

Effects on Restorations

The effects of air polishing on restorative materials have been extensively researched.

Extended use of air polishing on all restorative dental materials should be avoided.

Avoid air polishing on or near the following:

○ Amalgam alloy and other metal restorations, to prevent a matte finish, surface roughness, morphologic changes, and structural alterations

○ Composite restorations to prevent surface roughness or pitting

○ Porcelain, gold alloy, and glass ionomer restorations, to prevent surface roughness, staining, pitting, and loss of marginal integrity

○ Sapphire and pure titanium implants, to prevent surface alteration

Safety Issues

Air polishing safety concerns for the client, clinician, and others in the treatment area appear in the literature. Client concerns include the following:

Systemic problems from absorption of sodium bicarbonate prophy powder

Respiratory difficulties and potential for infection from inhaling contaminated aerosols

Stinging of the lips from the concentrated spray

Eye problems from spray entering the eyes, especially if contact lenses are worn

These problems can be managed by coating a client’s lips with a protective lubricant, using appropriate technique including safety suction devices, removing contact lenses, wearing safety glasses, and placing a protective drape over the client’s nose and eyes.

Because air polishing may cause bleeding and bacteremia, the American Heart Association (AHA) recommends antibiotic premedication to prevent infective endocarditis for clients at the highest risk for adverse outcomes (see Chapter 10).

It is important for the body to maintain a specific balance between acids and bases. Some individuals cannot adjust if this balance is disturbed. Owing to the potential absorption of sodium bicarbonate by the oral mucosa, air polisher manufacturers caution against using the sodium bicarbonate prophy powder during air polishing with such clients. Limited information is available on the systemic effects of sodium bicarbonate or aluminum trihydroxide absorption from air polishing powder.

Because of the marked rise in aerosols generated with air polishing, additional health hazards potentially exist for clients and healthcare professionals present during or after a procedure. To decrease potential risks, standard precautions including the following should be adhered to:

The clinician needs to wear a well-fitting face mask with recommended bacterial filtration efficiency (BFE) scores of 74% to 98%.

The client needs to rinse with a preprocedural antimicrobial such as 0.12% chlorhexidine gluconate for up to 2 minutes to reduce production of infectious aerosols.

Use high-volume evacuation, which will reduce aerosols better than a saliva ejector.

Disinfect contaminated surfaces as far away as 6 feet from the immediate treatment area to help prevent cross-contamination between clients. Contaminated surfaces, if not covered with disposable plastic drapes, should be cleaned and disinfected with an approved high-level surface disinfectant (see Chapter 7). To ensure safety of clinicians and clients, the CDC guidelines for infection control as outlined previously for rubber-cup polishing are followed.

Air polishing is included in the dental hygiene care plan only after a careful review of the client’s health and dental history and a thorough examination of the oral hard and soft tissues. A synopsis of the medical contraindications to air polishing can be found in Box 27-2. Table 27-3 contains a listing of other contraindications and precautions that should be considered when evaluating appropriateness of air polishing for a particular client.

BOX 27-2 Medical Contraindications and Precautions to Air Polishing

• Low-sodium diet or history of hypertension (for sodium-containing prophy powder only)^∗

• Respiratory illness that limits swallowing or breathing

• Communicable disease that can be transmitted via contaminated aerosols

• Renal insufficiency or end-stage renal disease

• Addison’s disease

• Cushing’s disease

• Metabolic alkalosis^†

• Medications such as mineralocorticoid steroids, antidiuretics, or potassium supplements^†

• High-risk clients needing antibiotic premedication may need to be premedicated for air polishing.

• Clients wearing contact lenses should remove them first and wear safety glasses.

^∗ Air polishing can be performed with sodium-free prophy powder (Cavitron Jet Fresh [blue bottle]).

^† Precautions needed, but these are not strict contraindications.

TABLE 27-3 Dental Contraindications and Precautions Related to Air Polishing

	Specially Processed Sodium Bicarbonate Air-Polishing Powder	Aluminum Trihydroxide Air-Polishing Powder (Sodium-Free)
Composite restorations or bonding	No	No
Luting agents	No	No
Porcelain restorations, including crowns, veneers, inlays, onlays	Yes, if margin is avoided; otherwise, no	No
Gold (foil or castings) restorations	Yes, if margin is avoided; otherwise, no	No
Compomer	No	No
Amalgam restorations	Yes	Yes
Microfilled composite restorations	No	No
Glass ionomer restorations	No	No
Hybrid composite restorations	No	No
Absence of stain	No	No
Exposed cementum or dentin	Yes	Yes
Areas of hypersensitivity	No	No
Immediately after deep scaling or root planing when acute gingival or periodontal inflammation is present	Yes	Yes

Tooth Whitening

Tooth whitening is a viable alternative for stain management when tooth stains are intrinsic. Tooth whitening is a cosmetic procedure. Many techniques ranging from OTC products to professionally dispensed whitening to in-office laser systems are available and vary significantly in cost to the client. Whitening procedures must be approached with caution. The dental hygienist has a responsibility to understand the processes involved in tooth whitening. It is also important to ensure that clients understand the ramifications of tooth whitening before its initiation. The dental hygienist’s role is summarized in Box 27-3.

Over-the-Counter Whitening Products

There are three types of OTC whitening toothpastes:

Toothpaste containing a mild abrasive to remove extrinsic stains and agents to prevent stain formation. All toothpastes contain some abrasives and are capable of potentially removing stains whether they are labeled “whitening” or not. Toothpastes with a high content of abrasives are not recommended for daily use.

Toothpaste containing a bleaching agent, such as papain, carbamide peroxide, or hydrogen peroxide (note that the American Dental Association [ADA] Council on Scientific Affairs does not recommend some of them for long-term use).

Toothpaste containing titanium dioxide; the titanium dioxide covers extrinsic stains like paint covers a wall and does not change the internal tooth color.

Some OTC products are a cause for concern in terms of efficacy and safety owing to the potential for overuse and abuse by uninformed clients. Commercial whitening kits containing an oxidizing agent and materials to form a “boil and fit” mouth tray are available. Oxidizing gel may seep out of improperly fitted trays and harm soft tissues. An acidic prerinse that can damage enamel is found in some kits. Laypersons may not know how to deal with side effects they may encounter. Once removed, extrinsic stain may be prevented by a client’s change in self-care practices.

Without a comprehensive oral examination to determine stain cause and the safest, most appropriate method to use in treating the stain, clients may neglect to seek appropriate care for what may be a serious undiagnosed oral problem. For example, a dark area on a tooth may be due to a carious lesion or a tooth in need of a root canal. Whitening would not remedy either situation. Clients should be encouraged to seek professional care to lighten teeth.

Professionally Dispensed Whitening Systems for Home Use

Professionally dispensed whitening systems (Table 27-4) involve the in-office fabrication of a custom mouth tray, dispensing of the appropriate whitening agent, and client education on how this is used at home with a prescribed frequency and time period (Figure 27-21). This procedure is also called nightguard vital bleaching (NGVB). The dentist monitors the client until the desired outcome is achieved. Home whitening with a custom-fitted tray and whitening agent is the superior tooth whitening method because of product innovations that control dentinal hypersensitivity and loss of enamel. It is lower in cost to the client than in-office bleaching, and it has the most scientific evidence supporting its effectiveness. It does require client adherence to the protocol for a good outcome. (See Chapter 35 for fabrication of custom-fitted bleaching trays.) In most cases an oxidizing agent, usually 10% to 30% carbamide peroxide, is loaded into a flexible polyvinyl, custom-made tray that the client wears 1 to 2 hours a day or overnight for a 2- to 6-week period. In addition to the oxidizing agent, Carbopol (carboxypolymethylene polymer) may be added to thicken the gel, improve adherence to the tooth surface, and prolong the release of oxygen. This additive keeps the gel contained within the tray and slows the chemical reaction.

TABLE 27-4 Some Professionally Dispensed Whitening Products

Figure 27-21 Custom-made maxillary and mandibular bleaching trays.

(Courtesy Dr. Brent B. Hutson.)

Home whitening is effective in producing a lightened tooth surface, but clients should be informed that the degree of change, especially with tetracycline-stained teeth, may be unpredictable. Therefore client expectations must be clarified before any treatment. Clients need to know the following:

Stains in the yellow to brown range respond better than stains in the blue to gray range.

Teeth with horizontal bands or striations of various colors, as seen with tetracycline-stained teeth, may bleach at different rates, making enamel defects more noticeable.

Although the teeth may look lighter, they may not necessarily be whiter, owing to their normal, intrinsic tooth color.

Tooth-colored restorations subjected to bleaching will not change color and may no longer match the color of the teeth after the bleaching procedure.

Whitening is temporary, and additional treatments may be necessary in 1 to 3 years, which carry cost and time commitment for the client. Longevity of whitening varies from client to client.

Side Effects of Tooth Whitening

Short-term side effects are usually minimal and disappear on cessation of treatment. The most common side effects are mild thermal tooth sensitivity and gingival irritation. Tooth sensitivity is attributed to the easy passage of the hydrogen peroxide through the enamel and dentin to the pulp, resulting in a reversible pulpitis. Use of a prescription self-applied fluoride gel or a shortened bleaching exposure time may decrease sensitivity. Clients with recession should not have bleaching because of the possibility of exposed dentin, which provides the hydrogen peroxide a direct route to the pulp. In 10% of the population there is a gap at the cementoenamel junction (CEJ) between the enamel and the cementum, leaving exposed dentinal tubules that can lead to extreme sensitivity. Gingival irritation may occur if the bleaching tray is overfilled. Use of a syringe dosage system, a highly viscous gel, and a properly fitted tray may prevent any excess from escaping the trays.

Occasionally, sore throats, tooth pain, tingling of tissues, and headaches are reported as side effects of tooth bleaching. Slight morphologic changes in the enamel have also been noted with the vital bleaching gels. A study, however, showed that 10% carbamide peroxide did not significantly alter enamel microhardness. Localized microstructural and chemical changes were seen, but these were not clinically significant. Long-term misuse (overuse) of whitening products can decrease enamel hardness.

Although wide variations in data exist concerning composite restorations, some composites may be more susceptible to alterations, and some higher-concentration bleaching agents are more likely to cause these alterations. These changes, however, are unlikely to be clinically significant. No effects on porcelain or ceramic materials have been reported. Whitening of teeth containing amalgam restorations is not contraindicated but should be approached with caution because some changes in amalgam have been noted. Another possible side effect involves the temporomandibular joint (TMJ). When fabricating the bleaching tray, a thin material should be used to avoid interference with the client’s occlusion. No long-term systemic effects have been identified. See Box 27-4 for a complete list of contraindications.

In-Office Whitening Procedures

In-office tooth whitening is any bleaching procedure performed in the office by a dental professional. Techniques may differ based on a number of factors: cause of the stain, tooth vitality, and the number of teeth needing the procedure (single tooth, multiple teeth, one arch, or both arches). Office time involved, client preference and compliance, cost, provider preference, and oral assessment findings are additional factors to consider when selecting the most appropriate procedure.

Vital tooth whitening is bleaching a tooth that has a vital pulp. In-office techniques for bleaching vital teeth can be classified as professional bleaching, power bleaching, conventional or traditional bleaching, laser bleaching, or combination bleaching. Often, the combination of office and home whitening procedures enhances the desired effect.

Nonvital tooth whitening is bleaching an endodontically treated tooth that has no pulp. For a nonvital tooth or teeth, the procedure is usually intracoronal and may also be combined with one of the procedures indicated for vital teeth.

In-Office Bleaching Procedures for Vital Teeth

Manufacturers of in-office bleaching systems have specific instructions for use of their products, and their instructions should always be followed. In general, the bleaching procedure for vital teeth involves the following:

Placement of a rubber dam, use of a light-cured paint-on dam, and/or protection of the gingival tissues with a petroleum jelly is necessary.

Teeth may or may not be etched before placement of the bleaching agent. A gel or liquid bleaching agent, usually 35% hydrogen peroxide, is applied to the enamel surface. If the liquid form is used, gauze squares saturated with the bleaching agent are placed on the facial surfaces. The bleaching agent is allowed to remain on the teeth for about 30 minutes. A heat source, visible light curing lamp (resin curing light), plasma arc, light-emitting diode (LED), xenon-halide light, or laser is applied to catalyze the oxidizing agent and accelerate the chemical reaction. The value of the heat or light source has not been established in the literature (Figure 27-22).

Local anesthesia must never be used during bleaching. Client discomfort is monitored at all times to avoid tissue burns or excess heat buildup in the pulp. Analgesics may be recommended for the first 24 hours postoperatively if tooth sensitivity is experienced.

At the end of the procedure, all excess bleaching agent should be removed with water before removing the rubber dam.

Figure 27-22 In-office bleaching procedure with a rubber dam, bleaching gel, and a resin curing light as the heat source.

(Courtesy Dr. Brent B. Hutson.)

The in-office bleaching procedure lasts from 30 to 60 minutes and may involve one to three appointments at 2- to 4-week intervals until teeth sufficiently lighten or no further color change is noted. This time interval between appointments allows the pulp to settle down in case irritation develops. Clients should be informed that white spots on the tooth might become whiter and result in a blotchy appearance. If tooth-colored restorations need to be done, it is advisable to wait 2 to 3 weeks to determine the correct color shade. In addition, resin bonds are significantly weakened after tooth bleaching, so this time interval prevents failed restorations owing to inadequate bond strength.

Intracoronal Bleaching

Intracoronal bleaching, a method of in-office bleaching, is used only for bleaching endodontically treated teeth and is usually performed by an endodontist. With both of the following techniques, the bleaching agent is placed within the tooth. Nonvital bleaching techniques usually fall into these two categories:

Thermocatalytic: The bleaching agent is usually 30% hydrogen peroxide, sodium perborate, or sodium hypochlorite. The agent is placed within the coronal portion of the pulp chamber with a cotton pellet after the cervical portion has been sealed with zinc phosphate or zinc oxide–eugenol cement to prevent penetration of the bleaching agent into the dentinal tubules and the possibility of cervical resorption. Heat (heat lamp, heated instrument, electric heating device, or an ultraviolet light) is applied to hasten the reaction.

Walking: The walking bleach method is so called because a paste of sodium perborate and hydrogen peroxide is placed in the coronal portion of the pulp chamber, the tooth is sealed, and the client is seen again in a week. At that time, the paste may be reapplied if further alteration in color is necessary. Often, only a small amount of color change can be achieved, but it may be sufficient to satisfy the client. This procedure is technique sensitive; failure to follow exact protocols may result in severe pain during or following the procedure. If the cervical area is not sealed well, cervical resorption may occur. To enhance the final effect, both nonvital bleaching methods may be combined with the professional or home bleaching methods for vital teeth.

Restorative Management of Stained Teeth

Deep stains, mottled or pitted teeth, and grayish-blue stains may need restorative procedures by the dentist, such as composite bonding, veneers, or full crowns to provide the client with a more esthetic appearance than can be achieved by whitening or microabrasion. All bleaching of teeth should be done before restorative procedures to ensure that crowns, bondings, and veneers will match the new enamel shade. Although not as conservative as bleaching, these procedures may assist the client in achieving a more desirable oral facial image. A dentist performs most restorative procedures, but the dental hygienist should be able to explain all procedures to the client.

Veneers

Veneers are thin, shell-like facings, usually made of composite resin or porcelain, bonded onto anterior facial tooth surfaces.

Indirect technique: The veneer is fabricated in a dental laboratory on a stone die made from an impression; a small amount of tooth structure must be removed for this restoration.

Direct technique: Teeth indicated for composite bonding are isolated, polished with pumice, and acid-etched. A bonding agent and an optional opaquer can be added before the composite is molded onto the facial surface. This procedure can change the appearance and shape of the tooth. After curing, the bonded area must be contoured, finished, and polished. Relatively inexpensive, this procedure is done quickly, requires only one visit, is good for young teeth with large pulps, and does not remove much tooth structure. However, it can look bulky and has the potential to chip and stain over time.

Porcelain veneers, although expensive, are ideal for older teeth. Fabrication involves an indirect technique as follows:

Tooth is prepared by removing a thin layer of enamel, making an impression, and sending the impression to the laboratory for construction of the porcelain veneer.

A temporary veneer is made and worn.

On the second visit the temporary veneer is removed and the permanent veneer is checked for proper fit. The tooth is then isolated, polished with pumice, etched, rinsed, and dried. A bonding agent and an optional opaquer are applied. The inside of the veneer is conditioned, and composite is added to bond the veneer to the tooth. The veneer is placed, and excess composite is removed.

If not designed properly, porcelain veneers can be bulky, stain at the margins, and chip. When well designed, they have good esthetic properties and are more durable than composite veneers.