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Prof. d-r R.Kabaktchieva -2014.  Soft, microbial dental plaque continually forms on the tooth surfaces, is the primary agent in the development of dental.

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Presentation on theme: "Prof. d-r R.Kabaktchieva -2014.  Soft, microbial dental plaque continually forms on the tooth surfaces, is the primary agent in the development of dental."— Presentation transcript:

1 Prof. d-r R.Kabaktchieva -2014

2  Soft, microbial dental plaque continually forms on the tooth surfaces, is the primary agent in the development of dental caries and periodontal diseases.  If plaque biofilm is completely removed with self-care procedures, dental caries and periodontal diseases can be prevented.

3  Plaque deposits can be removed either mechanically or chemically.  The focus of this lectur is the mechanical removal of plaque, using toothbrushes and toothbrushing techniques.

4 The History of the Toothbrush  Since ancient times, individuals have chewed twigs from plants with high aromatic properties.  In Arabic countries individuals used a piece of the root of the arak tree - the root fibers stood out like bristles; the fibers contained antibacterial oils and tannins.  ( A.D.) the Chinese invented a toothbrush with a handle and bristles. They used hog bristles  In 1780 in England, William Addis manufactured "the first modern toothbrush.“ This brush had a bone handle and holes for placement of natural hog bristles.

5  In the early 1900s, celluloid began replacing the bone handle.  Nylon bristles were introduced;  Nylon bristles did not have the hollow stem of natural bristles; therefore, they did not allow water absorption.  Other advantages of nylon bristles, were the ability to form the bristles in various diameters and shapes, and to round the bristle ends to be gentler on gingival tissues.

6  In 1916, Dr. Alfred C. Fones, founder of dental hygiene, wrote a textbook, Mouth Hygiene, which specifically directed dental hygienists to teach specific toothbrushing methods to schoolchildren.  In 1919, the American Academy of Periodontology developed guidelines for both toothbrush design and brushing techniques.

7 Fones School of Dental Hygiene - instructors and students during a toothbrush drill, circa early 1900.

8  In 1939, the first power toothbrush was developed in Switzerland and was introduced in the United States in the  In the 1980s, powered toothbrushes were revitalized with the introduction of the InterPlak.  Compared with manual toothbrushes, powered toothbrushes have shown an increased efficacyefficacy (ability to produce a desired effect);

9  Sonic-powered toothbrushes have been developed;  They remove more plaque compared with manual toothbrushes.  Most recently, battery-powered, disposable toothbrushes have been introduced.

10  A toothbrush is the primary instrument used for oral hygiene care.  There are many different types of toothbrushes.  There are manual and power toothbrushes, with each having various designs of the handle, head, and bristles.  These variations all have unique benefits.

11 Manual Toothbrush Designs  Manual toothbrushes vary in size, shape, texture, and design Fig. Lateral profiles of selected toothbrushes

12  A manual toothbrush consists of a head with bristles and a handle.bristles  Тhe bristles are bunched together, and form tufts.  The head is divided into the toe, and the heel. Fig. Parts of a toothbrush.

13  The shank occurs between the handle and the head.  Toothbrushes are manufactured in different sizes: large, medium, and small

14  Toothbrushes are differ in their hardness or texture being classified as: hard, medium, soft, or extra soft.  Extra soft and soft toothbrush bristles are preferred, because hard bristles damage teeth by causing abrasion of the tooth surface.

15 Figure.Figure. Cross-sectional profile of toothbrushes: Figure. Overhead appearance of toothbrushes,

16 Toothbrush Profiles  Viewed from the side, toothbrushes have four basic lateral profiles: concave, convex, flat, multileveled rippled or scalloped.

17  The concave shape, with shorter bristles in the middle of the head, may be most useful for increased cleaning of facial tooth surfaces.  Convex shapes, with longer bristles in the middle of the head, appear more useful for improved cleaning of lingual surfaces.  Toothbrushes with multilevel profiles were consistently more effective,especially when interproximal efficacy was evaluated.

18 Nylon Versus Natural Bristles  The nylon bristle is superior to the natural hog bristle:  Nylon bristles flex more than natural bristles before breaking;   Nylon bristles do not split or abrade and are easier to clean.  The shape and stiffness of nylon bristles can be standardized.

19 Bristle Shape  Nylon bristles can be manufactured in various dimensions.  A thinner diameter filament allows the bristle to be softer and more resilient.  Angled filaments remove direct pressure from the tooth and gingiva, and therefore appear to be more flexible. Angled filaments  Еnd-rounded tips are recommended for the safety of hard and soft oral tissues.

20 Fig. End rounding of toothbrush bristle.

21 Manual Toothbrushing Methods The purposes of toothbrushing include:  (1) removal of plaque biofilm and disturbance of its re-formation;  (2) removal of food, debris, and stain from the oral cavity;  (3) stimulation of the gingival tissues;  (4) application of a dentifrice containing specific ingredients to address caries, periodontal disease, or sensitivity.

22  The several different toothbrushing methods remove plaque most efficiently,  Any method that is taught should not damage hard or soft tissues, or cause excessive tooth wear.

23 The most natural brushing methods:  horizontal scrub technique;  rotary motion such as the Fones technique;  simple up-and-down motion over the maxillary and mandibular teeth, ( the Leonard technique.)

24 Тhese techniques can clean:  the facial,  the lingual,  the occlusal surfaces of the teeth;  all are ineffective in cleaning interproximal areas.  the Bass technique is effective in cleaning the sulcus.

25 Bass Method  The Bass method is acceptable for all patients.Bass method  This method is effective at removing plaque at the gingival margin and directly below it.

26 The toothbrush bristles are angled apically at a 45-degree angle to the long axis of the tooth. The filaments are then gently placed subgingivally into the sulcus. With very light pressure, the brush is moved with very short horizontal strokes, while keeping the bristles in the sulcus. After several vibrations, the bristles are removed from the sulcus, and the brush is repositioned on the next 2 or 3 teeth. Fig. Bass technique.

27 Technique Bristle Position Brushing Motion Effect Claimed Bass At 45 degrees, with tips in sulcus Vibratory, horizontal jiggle Supragingiv al cleansing, gingival stimulation

28 Rolling Method  The rolling technique is most appropriate for children.  The bristles are positioned apically along the long axis of the tooth.  The edge of the brush head should be touching the facial or lingual aspect of the tooth.  Then with light pressure the bristles are rolled against the tooth from the apical position toward the occlusal plane.  This motion is repeated several times; then the brush is repositioned on the next teeth, with bristles overlaping a portion of the teeth previously cleaned.  The heel or toe of the brush is used on the lingual aspect of the anterior teeth

29 Technique Bristle Position Brushing Motion Effect Claimed Rolling Apically against attached gingiva Sweep in arc toward occlusal surface Supragingiva l cleansing, gingival stimulation Fig. Rolling stroke toothbrushing technique

30 Stillman Method  The Stillman method was originated to massage and stimulate the gingiva while cleansing the cervical areas.Stillman method  The bristles are positioned apically along the long axis of the tooth.  The edge of the brush head should be touching the facial or lingual aspect of the tooth.  Then the brush is slightly rotated at a 45-degree angle and vibrated over the crown.

31 TechniqueBristle Position Brushing Motion Effect Claimed StillmanAgainst apical part of gingiva and cervical part of tooth Vibratory, pulsing strokes Gingival stimulation Fig. Stillman toothbrushing technique seen diagrammatically.

32 Charters Method  The Charters technique is effective for cleaning around devices used to correct improper contact of opposing teeth (orthodontic appliances), and plaque under abutment teeth of a fixed bridge.Charters technique  The bristles are placed at a 45-degree angle toward the occlusal or incisal surface of the tooth.  The bristles should touch at the junction of the free gingival margin and tooth.  A circular vibratory motion is then activated.

33 TechniqueBristle Position Brushing Motion Effect Claimed Charters At 45 degrees to tooth Circular, vibratory strokes Gingival stimulation, interproximal cleansing Fig. Charters toothbrushing technique.

34 Fones Method  The Fones method is a easy technique for young children to learn.Fones method  The teeth are clenched, and the brush is placed inside the cheeks.  The brush is moved in a circular motion over both maxillary and manibular teeth.  In the anterior region, the teeth are placed in an edge-to-edge position and the circular motion is continued.  On the lingual aspect, an in-and-out stroke is used against all surfaces.  This technique can be damaging if done too vigorously

35 Technique Bristle Position Brushing Motion Effect Claimed Fones At 90 degrees to tooth Large circles over teeth and gingiva Supragingival cleansing, gingival stimulation Fig. Fones toothbrushing technique: Circulatory motion extending from maxillary to mandibular teeth.

36 Leonard Method  Тhe toothbrush is placed at a 90-degree angle to the long axis of the tooth.  The teeth are held in an edge-to-edge position.  Next, the toothbrush is moved in a vertical, vigorous motion up and down the teeth.  The maxillary and mandibular teeth are brushed separately.

37 TechniqueBristle Position Brushing Motion Effect Claimed Leonard At 90 degrees to tooth Vertical strokes Supragingival cleansing, gingival stimulation Fig. Leonard toothbrushing technique

38 Horizontal Method  In the horizontal technique, the teeth are placed edge to edge, while the brush maintains a 90-degree angle to the long axis of the tooth.  The brush is then moved in a horizontal stroke.  This technique is known to cause excessive toothbrush abrasion

39 TechniqueBristle Position Brushing Motion Effect Claimed HorizontalAt 90 degrees to tooth Horizontal strokes Supragingival cleansing, gingival stimulation Fig. Horizontal toothbrushing technique.

40 Smith Method  The Smith method is a physiologic technique, which follows the pattern that food follows when it is in the mouth during mastication.  The bristles are positioned directly onto the occlusal surface.  The brush is then moved back and forth with the bristles reaching from the occlusal surface to the gingiva.  Smith also recommends a few gentle horizontal strokes to clean the sulcus areas near furcations.

41 TechniqueBristle Position Brushing Motion Effect Claimed SmithAt occlusal surface Sweep toward gingiva Supragingival cleansing Fig. Smith toothbrushing technique.

42 Scrub Toothbrushing Method  The scrub toothbrushing technique is a combination of horizontal, vertical, and circular strokes.  It also incorporates vibration movements in certain areas.

43 Fig. Scrub toothbrushing technique.

44 Modified Brushing Methods  In attempts to enhance brushing of the entire facial and lingual tooth surfaces, the original techniques have been modified.  The modified brushing technique integrates a rolling stroke after use of the vibratory motion.  The position of the brush is maintained after the completion of the original method's stroke.  The bristles are then rolled coronally over the gingiva and teeth.  During this rolling motion, care should be taken that some of the filaments reach the interdental areas.

45 Technique Bristle Position Brushing Motion Effect Claimed Modified (in combination with an above method) Sweep toward occlusal surface Supragingival cleansing

46 Powered Toothbrushes  Powered toothbrushes were first advertised in  Broxadent was introduced in the 1960.

47 Fig.Fig. Selected power toothbrushes, from left to right: Crest SpinBrush; Oral-B Sonic Complete; Sonicare Elite.] design of the power toothbrush

48 The power toothbrushes can be categorized as: - mechanical, - sonic, - ionic.

49  A mechanical brush uses the motion of the bristles to remove the plaque and debris.  The sonic toothbrush emits sound waves in addition to the movement of the filaments.  The ionic toothbrushes temporarily reverse the negative ionic charge of a tooth to a positive charge. A portion of the toothbrush, that is positively charged, attracts the plaque and food particles away from the tooth.

50  The main movements in the power toothbrushes are oscillation, reciprocation, and rotational.  The oscillation movement takes the bristles in a consistent back-and-forth movement.oscillation movement  The reciprocation moves the bristles up and down or back and forth.  The rotational movements are circular.

51 Rotati ng

52 Speed of a powered toothbrush  The typical brushes movements - from 3,800 to 7,600 per minute.  A pulsation-type head can produce approximately 40,000 pulses per minute

53 POWERED TOOTHBRUSH METHODS AND USES  Each tooth and corresponding gingival areas should be brushed separately, always with light, steady pressure.

54 Toothbrushing Time and Frequency  Dental providers advised patients to brush their teeth after every meal.  If plaque is completely removed every other day, no harmful effects will occur in the oral cavity.  Very few individuals completely remove plaque; therefore, frequent brushing is still extremely important and recommended.

55  The repeated brushings will maximize sulcular cleaning as a measure to control periodontal disease, as well as introduce more frequent use of fluoride dentifrices to control caries.

56  Dentis suggest 5 to 10 strokes in each area or advocate the use of a timer.  The child should be encouraged to brush for up to 2-3 minutes and to use a timing device.

57 Systematic pattern for brishing  To begin with the distal surface of the most posterior tooth, and to continue brushing the surfaces around the maxillary (upper) arch until the last molar on the other side of the arch has been reached.  The mandibular (lower) arch is then brushed in a similar manner. It is important to explain to the patient that the bristles should always overlap previously cleaned teeth.


59 Clinical Assessments of Toothbrushing  Disclosing agents provide a means of evaluating of cleaning the teeth.  Disclosing agents, ( disclosants), may be in either a liquid or a tablet form. Disclosing agents  They should be swished around in the mouth for 15 to 30 sec..  They allow the patient to see plaque in the mouth before or after brushing.

60 Disclosing agentsDisclosing agents allow the patient to see plaque in the mouth before or after brushing

61 Toothbrush Replacement  The average life of a manual toothbrush is 2 to 3 months.

62 Tongue Brushing  The tongue is anatomically perfect for harboring bacteria.  The fissuring or prominent papilla, should be regularly cleaned.

63  Tongue cleaners, are curved so they can be placed over the tongue without touching the teeth.  These instruments are swept over the dorsum of the tongue to remove bacterial plaque and debris.

64 In initiating effective toothbrushing, it is necessary to:  (1) select the appropriate toothbrush(es) for the patient;  (2) create individual goals for toothbrushing and explain the need for good oral hygiene;  (3) teach a technique or combination of brushing methods necessary to meet established goals;  (4) assess and refine toothbrushing techniques as a part of the total oral hygiene program.

65 Simplified Oral Hygiene Index | OHI-S - OHI-S (Simplified) - (Greene and Vermillion, 1964)

66  The OHI-S, like the OHI, has two components: - the Debris Index - the Calculus Index. Each of these indexes, is based on numerical determinations representing the amount of debris or calculus found on the preselected tooth surfaces.

67 SELECTION OF TOOTH SURFACES  The six surfaces examined for the OHI-S are selected from four posterior and two anterior teeth.  In the posterior portion of the dentition, usually the first molar (16, 26,36,46). but sometimes the second (17) is examined.  In the anterior portion of the mouth, the labial surfaces of the upper right (11) and the lower left central incisors (31) are scored. In the absence of either of this anterior teeth, the central incisor (21 or 41 respectively) on the opposite side of the midline is substitted.

68 The buccal surfaces of the selected upper molars and the lingual surfaces of the selected lower molars are inspected. Тhe labial surfaces of the upper right (11) and the lower left central incisors (31) are scored.

69 Criteria for classifying debris ScoresCriteria 0No debris or stain present 1Soft debris covering not more than one third of the tooth surface, 2Soft debris covering more than one third, but not more than two thirds, of the exposed tooth surface. 3Soft debris covering more than two thirds of the exposed tooth surface.


71 Criteria for classifying calculus ScoresCriteria 0No calculus present 1Supragingival calculus covering not more than third of the exposed tooth surface. 2Supragingival calculus covering more than one third but not more than two thirds of the exposed tooth surface or the presence of individual flecks of subgingival calculus around the cervical portion of the tooth or both. 3Supragingival calculus covering more than two third of the exposed tooth surface or a continuos heavy band of subgingival calculus around the cervical portion of the tooth or both.

72 CALCULATION EXAMPLE:  After the scores for debris and calculus are recorded, the Index values are calculated.  For each individual, the debris scores are totaled and divided by the number of surfaces scored.  The average individual score is known as the Simplified Debris Index (DI-S).  The same methods are used to obtain the calculus scores or the Simplified Calculus Index (CI-S).

73  The average individual debris and calculus scores are combined to obtain the Simplified Oral Hygiene Index.  The CI-S and DI-S values may range from 0 to 3;  Тhe OHI-S values from 0 to 6.

74 The following example shows how to calculate the index. The scores for debris and calculus should be tabulated separately and index for each calculated independently, but in the same manner. Debris Index = (The buccal-scores) + (The lingual-scores) / (Total number of examined buccal and lingual surfaces). Debris Index = (9+4) / 6 = 2.2 Right molarAnteriorLeft molarTotal BuccalLingualLabial BuccalLingualBuccalLingual Upper Lower

75 Calculus Right molarAnteriorLeft molarTotal BuccalLingua l Labial BuccalLingua l BuccalLingua l Upper Lower Calculus Index = (4+3) / 6= 1.2

76  The average individual or group debris and calculus scores are combined to obtain simplified Oral Hygiene Index, as follows. Oral Hygiene Index = Debris Index + Calculus Index = 3.4

77 Dentifrices, Mouthrinses, and Chewing Gums  Dentifrices and mouthrinses are major products for routinely administering effective cosmetic and therapeutic agents in the mouth. therapeutic  Dentifrices are substances used to clean the teeth. Dentifrices  Mouthrinses are used to flush food debris from the oral cavity, freshen breath, or if fluoridated, to deposit fluoride on the teeth.  Chewing gums are products with cosmetic claims and the ability to deliver therapeutic compounds.

78  Dentifrices are marketed: - as toothpastes - as gels, - as toothpowders (to a lesser extent).  Some dentifrices are sold as: - liquid gels, - liquid pastes, - stripes, ( breath strips).  All are sold as either therapeutic or cosmetic products.

79  A therapeutic dentifrice must reduce some disease-related process in the mouth - caries, gingivitis, plaque, or tooth sensitivity.  The purpose of a cosmetic toothpaste is to clean and polish the teeth.

80  Toothpastes contain several or all of the ingredients: Abrasives, Water, Humectants, Foaming agent (soap or detergent), Binding agent, Flavoring agent, Sweetening agent, Therapeutic agent, Coloring or preservative.  Gel dentifrices contain the same components as toothpastes, except that gels have a higher proportion of the thickening agents.  Both tooth gels and toothpastes are equally effective in plaque removal and in delivering active ingredients.

81 Abrasives  The degree of dentifrice abrasiveness depends on the hardness of the abrasive, size and shape of the abrasive particles.dentifrice abrasiveness

82 The most common types of abrasives used are:  Carbonates include calcium carbonate (chalk) and sodium carbonate (baking soda).  Sodium monofluorophosphate - be used when the combination of fluoride and calcium carbonate is desired.odium monofluorophosphate  Phosphate abrasives include calcium pyrophosphate and dicalcium phosphate dihydrate.  Silicas, such as silicon oxides, mechanically cleanse the tooth, Silicas  Aluminum oxides and perlites have also been introduced into dentifrice formulas,

83  Humectants were added to maintain the moisture and prevent hardening. Humectants  Commonly used humectants are: - sorbitol, - mannitol, - glycerol, - propylene glycol.  Preservatives such as sodium benzoate are added to prevent the growth of MO.

84 Detergents  The soaps disappeared from dentifrices, when detergents appeared on the market.  Today, sodium lauryl sulfate (SLS) is the most widely used detergent.sodium lauryl sulfate  It has antibacterial properties, and a low surface tension, which facilitates the flow of the dentifrice over the teeth.  Sodium lauryl sulfate is active at a neutral pH, has a flavor that is easy to mask, and is compatible with the current dentifrice ingredients.

85 Flavoring and Sweetening Agents  Synthetic flavors provide the desired taste: - Spearmint, - peppermint, - wintergreen, - cinnamon, - vanilla They give toothpaste a pleasant taste, aroma, and refreshing aftertaste. Essential oils such as thymol, menthol, may provide a "medicinal" taste to the product. In addition, these oils may impart antibacterial effects.

86 Sweetening Agents  Noncariogenic sweetening agents: saccharin, cyclamate, sorbitol, and mannitol.  Sorbitol and mannitol are sweetening agents and humectants.  Glycerin is a humectant and adds to the sweet taste.  A new sweetener is xylitol – has an anticaries capability by facilitating the remineralization of incipient carious lesions.

87 Baking-Soda Dentifrices  All contain hydrated silica, which is compatible with fluoride.  Baking-soda dentifrices actually contain only a small amount of baking soda, in addition to the standard fluoride-compatible abrasives.

88 Therapeutic Dentifrices  The most commonly used therapeutic agent added to dentifrices is fluoride, which aids in the control of caries.  In 1960, the Council on Dental Therapeutics of the American Dental Association classified Crest toothpaste with stannous fluoride as a caries prophylactic dentifrice.

89  The original level of fluoride in dentifrices and gels was restricted to 1,000 to 1,100 ppm fluoride and a total of no more than 120 mg of fluoride in the tube.  Most dentifrices today still contain 1,000 ppm.  Therapeutic toothpastes, dispensed on prescription, could contain up to 260 mg or 4,950 ppm of fluoride in a tube.

90 The following fluorides are generally recognized as effective and safe for sales:  0.22% sodium fluoride (NaF) at a level of 1,100 ppm,  0.76% sodium monofluorophosphate (MFP) at a level of 1,000 ppm,  0.4% stannous fluoride (SnF 2 ) at a level of 1,000 ppm.  Fluoride levels were increased to 1,500 ppm sodium monofluorophosphate - “ Extra Strength Aim”.  A prescription dentifrice, Colgate PreviDent 5,000, contains 5,000 ppm of fluoride.

91  The addition of calcium and phosphate ions to a fluoride dentifrice may improve the ability of enamel to resist caries initiation and subsequent progression of a lesion.  Calcium phosphate encourages the remineralization of enamel by rapidly hydrolyzing to form apatite.

92 Stannous Salts  Stannous fluoride (SnF 2 ), specifically the stannous ion, has reported activity against caries, plaque, and gingivitis. Stannous fluoride  but his long-term stability in dentifrices and mouthrinses has been questioned.  Superior efficacy has been shown for Crest Pro-Health (Procter & Gamble) -this product combines a stabilized stannous fluoride (0.454%) and sodium hexametaphospate.

93 Triclosan  Triclosan is a broad-spectrum antibacterial agent, marketed by its manufacturer, Ciba- Geigy, for use in oral products under the trade name Irgacare. Triclosan  Colgate Total developed by Colgate- Palmolive, contains triclosan, a patented copolymer, "Gantrez," and fluoride.  A triclosan dentifrice inhibits plaque regrowth and provides anti-calculus activity, thereby reducing gingival inflammation.

94 Mouthrinses  Freshening bad breath has been the traditional purpose of mouthrinses.  However, mouthrinses can be cosmetic, therapeutic, or both.  Therapeutic mouthrinses Therapeutic mouthrinses - Therapeutic benefits include a reduction in bacterial plaque, gingivitis, and dental caries. - Mouthrinses are often used daily by patients; - It is important that patients understand proper usage of mouthrinses to achieve successful outcomes. When antimicrobial mouthrinses are used daily along with brushing and flossing, they are most effective in reducing plaque and gingivitis.

95 Therapeutic Mouthrinse Agents Chlorhexidine  is a cationic compound that binds to the hydroxyapatite of tooth enamel, the pellicle, plaque bacteria, the extracellular polysaccharide of the plaque, and especially to the mucous membrane.  The chlorhexidine adsorbed to the hydroxyapatite is believed to inhibit bacterial colonization and prevent pellicle formation.  The FDA has approved prescription plaque- control rinses containing 0.12% chlorhexidine.

96 Fluoride Rinses  Fluoride mouthrinses are effective in the reduction of the incidence of dental caries. Fluoride mouthrinses  They are intended for daily or weekly use, depending on their categorization as: - low-concentration/high-frequency or - high-concentration/low-frequency rinses.  Some low-concentration mouthrinses are available over the counter.

97  The active agents in fluoride mouthrinse products are NaF, acidulated phosphofluorides, or SnF.  Concentration for daily use is 0.05% (250 ppm);  For weekly use the concentration of each agent is 0.2% (900 ppm), 0.44% (440 ppm), and 0.63% (250 ppm), respectively.  The dose directions are 5 ml (1 teaspoon) of product once daily  The rinse is to be swished for 60 seconds and then expectorated.

98  For stannous fluoride, the daily rinse concentration is diluted with water to produce a 0.1% concentration.  Stannous fluoride and acidulated phosphofluoride mouthrinses are not recommended for weekly usage.

99  It is found that the fluoride in mouthrinses is retained in dental plaque and saliva to help prevent dental caries.  Studies report a 30% to 40% average reduction in the incidence of dental caries for fluoride mouthrinse users.

100  Fluoride mouthrinses are highly indicated for patients who have a history of moderate-to- rampant caries, who are undergoing orthodontia.  Fluoride mouthrinses are not recommended for children under 6 years of age or those who have difficulty swishing and expectorating.

101 END

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