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Saliva and Oral Health Part 1 Maintaining Oral Health Preventing Dental Disease A CPD Module for Dental Professionals 1 Hour Verifiable CPD.

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Presentation on theme: "Saliva and Oral Health Part 1 Maintaining Oral Health Preventing Dental Disease A CPD Module for Dental Professionals 1 Hour Verifiable CPD."— Presentation transcript:

1 Saliva and Oral Health Part 1 Maintaining Oral Health Preventing Dental Disease A CPD Module for Dental Professionals 1 Hour Verifiable CPD

2 Saliva and Oral Health Saliva - Production - Composition - Function Biofilm New Insights - Composition - Activity - Fluoride resistance Chewing Gum and Saliva - Flow rate - Clearance - Buffering Caries - Plaque pH - Demineralisation-Remineralisation Erosion - Prevalence - Causes - Aetiology- Management Clinical Assessment - Examination - Chair side Tests - Recommendations (CRA BEWE) Overview

3 Saliva and Oral Health Major Salivary Glands - Parotid - Sublingual - Submandibular Minor Salivary Glands -Lips, tongue, cheek, palate Saliva Secretion - Parotid Serous saliva - Sublingual Mucous saliva - Submandibular Mixed saliva Saliva

4 Saliva and Oral Health Saliva Salivary Acini Basic secretory units of salivary glands. Serous Cells - Stain darkly. - Wedge shaped with round nucleus. -Tight spherical formation. Mucous Cells - Stain lightly. - Tubular shaped with flattened nucleus. - Open formation larger central lumen. Serous Cell Basement membrane Mucous Cell Intercalated duct Salivary duct (secretory) End piece Serous Demilune Mixed Salivary Acinus © Reeves 2013

5 Saliva and Oral Health Saliva Histology varies by gland type Serous Acini Mucous Acini Mixed Acini Parotid Sublingual Submandibular

6 Saliva and Oral Health Saliva Formation Stage One: Primary Saliva Saliva Local Vasculature ACINI- water and ions derived from plasma Saliva formed in acini flows down DUCTS to empty into the oral cavity ©Reeves 2013

7 Saliva and Oral Health Saliva Saliva Formation Stage Two: Final Saliva Water and electrolytes Proteins Na + & Cl - K+K+ H2OH2O Isotonic Primary Saliva Hypotonic Final Saliva Concentration Gradient ©Reeves 2013 Concentration Gradient

8 Saliva and Oral Health 99.4 % Water 0.2 % Soluble inorganic substances: sodium, potassium, calcium, chloride, bicarbonate, phosphate, fluoride 0.3% Soluble organic substances: proteins, digestive enzyme (amylase), mucins, antibodies (immunoglobulins), urea, peroxidases, antioxidant enzymes (SOD catalase gluathione) 0.1 % insoluble substances Saliva The Composition of Saliva

9 Saliva and Oral Health Composition Unstimulated Stimulated Water99.55% 99.53% Solids0.45%0.47% Flow Rate (ml/min) 0.32  0.232.08  0.84 pH7.04  0.287.61  0.17 Sodium (mmol/L) 5.76  3.4320.67  11.74 Potassium 19.47  2.18 13.62  2.70 Bicarbonate 5.47  2.46 16.03  5.06 Phosphate 5.69  1.912.70  0.55 Chloride16.40 ± 2.0818.09  7.38 Calcium1.32 ± 0.241.47 ± 0.35 Na + & Cl - K+K+ Water and Electrolytes Saliva and Oral Health Edgar M, Dawes C, O’Mullane D Eds. 4th Ed 2012 Saliva The Composition of Saliva

10 Saliva and Oral Health Na + & Cl - K+K+ Water and Electrolytes Saliva The Composition of Saliva Dawes, C. JADA 2008;139:suppl 2:18S-24S

11 Saliva and Oral Health Saliva Water Solids Flow Rate pH Organic Total protein MUC5B MUC7 Amylase Lactoferrin Statherin Albumin Glucose Lactate Urea Unstimulated Stimulated 99.55 % 99.53% 0.45% 0.47% 0.32 ± 0.23 2.08 ± 0.84 7.04 ± 0.28 7.61 ± 0.17 1630 ± 720 1350 ± 290 830 ± 480 460 ± 200 440 ± 520 320 ± 330 317 ± 290 453 ± 390 8.4 ± 10.3 5.5 ± 4.7 4.93 ± 0.61 51.2 ± 49.0 60.9 ± 53.0 79.4 ± 33.3 32.4 ± 27.1 0.20 ± 0.24 0.22 ± 0.17 3.57 ± 1.26 2.65 ± 0.92 6.86 2.57 ± 1.64 Saliva and Oral Health, Edgar M. Dawes C., O’Mullane, D. Eds. 4 th Ed, 2012

12 Saliva and Oral Health Saliva Resting Saliva Secretion -Submandibular - 60% -Parotid - 25% -Sublingual~ 7-8% -Minor glands~ 7-8% Oral Protection System - Secretion rate: 0.3-0.4 mls/min - Texture: Viscous (mucus) - Rich in mucins - pH value 5.7-7.1 - Functions: Coating of the teeth: salivary pellicle - Lubrication of oral mucosa Stimulated Saliva Secretion -Parotid 60% -Submandibular 30% -Sublingual ~ 10% and minor glands Oral Repair System - Secretion rate: 1-3mls/min - Consistency: Thin (serous) - Rich in minerals - pH value: 7.0-7.8 - Functions: Clearance, buffer system, remineralisation The Functions of Saliva

13 Saliva and Oral Health SalivaryFunctions Anti-Bacterial sIgA Peroxidases Buffering Carbonic anhydrases HCO 3 Digestion lipase, amylase mucins Mineralization Ca, Fl, PO 4 Lubrication Viscosity Elasticity Mucins Statherins Tissue Coating Mucins, PRPs Amylases Anti-Fungal Candida: Histatins Anti-Viral Cystatins Mucins Saliva The Multiple Functions of Saliva Figure adapted from M.J. Levine. 1993

14 Saliva and Oral Health Saliva The Major Functions of Saliva Digestion & TasteProtectionManipulation Dissolve solids Starch digestion (amylase) Gustatory sensation Facilitate chewing Swallowing Bolus formation Buffer - plaque acids (foods) extrinsic acids (reflux) intrinsic acids Antibacterial Oral ecology balance Pathogen defence Mouth clearance/rinsing Food and bacteria Prevent demineralisation Aid remineralisation Hydrates mucous membrane Attachment - Saliva proteins coat enamel surface and allow specific absorption of primary colonisers Food - Saliva may act as a carbon source and select for healthy bacterial balance

15 Saliva and Oral Health Biofilm ©Reeves2013 Streamers Bacterial Microcolonies Fluid Channels Pellicle Tooth Surface Flow Biofilm: a well organized, cooperating community of microorganisms. - A complex community of highly organised bacterial colonies. - Each community contains a mix of microorganisms. - Arranged in micro-colonies surrounded by a protective matrix. - With a communication system of fluid channels: Quorum sensing

16 Saliva and Oral Health Biofilm (König 1987) 1 st Phase: immediately to approximately 4 hours Formation of aquired pellicle from salivary glycoproteins and maturation. Early colonisation from initial bacteria mainly Streptococcus strains. 2 nd Phase: 4 to 48 hours Colonisation of predilection sites, i.e. fissures, iatrogenic retention factors (restorations/overhangs/ortho brackets) and white spots. 3 rd Phase: 3 to 7 days Aerobic bacterial metabolic products compromise the hard dental tissues; anaerobic bacterial metabolic products compromise the soft tissues. 4 th Phase: 7 to 14 days Mature plaque biofilm is established that consists of sessile bacteria firmly attached to the hard dental tissues and planktonic (floating) bacteria.

17 Saliva and Oral Health Early Colonizers Late Colonizers Fl- Biofilm The Formation of Biofilm Quorum sensing Salivary Pellicle Fl- resistance Enamel Surface Statherin  -amylase Proline-rich protein Salivary agglutinin Sialylated mucins Strep. oralis Strep. sanguis Strep. mitis Strep. gordonii A.oris A.naeslundii A.israelii C.achracea C.gingivalis C.sputigena AA T.forsythia PG T.denticola

18 Saliva and Oral Health Sugar-Free Gum Saliva flow rates under stimulation Saliva flow (ml in 20 min) Un-stimulated saliva Stimulated saliva after chewing paraffin Stimulated saliva after chewing sugar- free gum (Edgar 1993) - Chewing gum increases the saliva flow rate up to 10 times. - “Empty” chewing, without flavor additive (e.g., paraffin), only stimulates up to 5 times. - Chewing sugar-free gum with flavor additive improves flushing and accelerates the removal of soluble compounds. Salivary Flow Rate

19 Saliva and Oral Health Sugar-Free Gum Polyol-sweetened gum stimulates the production of saliva by two mechanisms: - Gustatory stimulation (taste buds) - Masticatory action (periodontal mechanoreceptors) (Dawes and Macpherson. 1992) Salivary Flow Rate

20 Saliva and Oral Health Sugar-Free Gum - Salivary stimulation lasts more than 2 hours with SF gum. - Flavour and chewing increase salivary flow. (Dawes, C., et al. Arch Oral Biol 2004, 49, 665-669.) Salivary Flow Rate Unstimulated flow rates of less than 0.1 mL/minute are considered evidence of hypo-salivation

21 Saliva and Oral Health Sugar-Free Gum Salivary Flow Rate and Xerostomia* -Chewing sorbitol gum increased saliva flow rates and neutralized plaque pH drop from sucrose in subjects with xerostomia. 1,2 - 69% of cancer patients with xerostomia preferred chewing gum to artificial saliva 3 ; 60% of hemodialysis patients preferred gum to saliva substitutes. 4 - Gum chewing (12 months, 2x/day) increased stimulated saliva flow rates in 111 frail older people. 5 -A 6 month study in 186 older (community-dwelling) adults showed significant improvements in plaque and gingival indices, but not saliva flow 6 ; self-perceived oral health status improved significantly in the gum group. 1.Markovic N; Abelson DC; Mandel ID (1988): Gerodont. 7: 71-75 2.Abelson DC, Barton J, Mandel ID (1990): J Clin Dent 2: 3-5 3.Davies AN (2000): Palliat Med 14: 197-203 4.Bots CP, Brand HS, et al (2005): Palliat Med 19: 202-207 5.Simons D, Brailsford SR, Kidd EAM, Beighton D (2002): J Am Geriatr Soc 50: 1348-1354 6.Al-Haboubi M, Zoitopoulos L, Beighton D, Gallagher JE (2012): Community Dent Oral Epidemiol 40: 415-424 Sugar-free gum may have benefits in older and medically-compromised patients * Module Two

22 Saliva and Oral Health Sugar-Free Gum Oral Clearance 15 10 5 0 0 Unstimulated Flow Rate UNSTFR(ml/min) Halftime(min) Saliva and Oral Health, Edgar M. Dawes C., O’Mullane, D. Eds. 4 th Ed, 2012 - Relies on swallowing and flow rate. - Higher salivary flow rate = increased clearance. - Unstimulated flow rate < 0.2ml/min = prolonged clearance. - Prolonged clearance = greater risk of caries. - Greater risk of acid erosion. Effect of changes in the UNSTFR on the clearance halftime of sucrose

23 Saliva and Oral Health Sugar-Free Gum Buffering Capacity Saliva stimulation and buffering of acids by chewing gum pH value 10% sugar solution Chewing gum with sugar substitute Time in minutes (Stoesser 1996) -Buffer capacity is the ability to neutralise acids (buffering). -The pH value is raised due to the increased concentration of bicarbonate in stimulated saliva. (Bicarbonate increases from 5.47 unstimulated to 16.03mmol/L in stimulated saliva). -Increased flow rate exposes hard tissues to low pH for a shorter period. ( Flow rate increases from 0.32 ml/min unstimulated to 2.08ml/min in stimulated saliva). Fast flowing saliva neutralises plaque (pH value increases).

24 Saliva and Oral Health Caries Plaque pH Manning RH, Edgar WM (1993) Brit Dent J 174: 241-4 Plaque pH Time (min) Factors affecting plaque acids - Fermentable carbohydrates. - Oral bacteria produce: - Extracellular polysaccharides in the presence of excess sucrose. - Glucans increase plaque adhesion and thickness. - Fructans produce acid metabolites. - Intracellular polysaccharide stores provide ongoing acid production in resting plaque. Saliva stimulation from chewing gum helps to neutralise plaque acids

25 Saliva and Oral Health Caries Plaque pH Plaque buffering systems - Bicarbonate is the most important buffering system. - Bicarbonate concentration increases with salivary flow. - Directly increases plaque pH. - Urea from saliva is converted to ammonia by bacteria in plaque with urease activity. - Ammonia is highly alkaline and neutralises plaque pH. - The intrinsic buffering capacity of plaque. - Calcium phosphate crystals in plaque dissolve in acid conditions. - Increasing buffering capacity. ©Reeves2013 Bicarbonate diffuses from saliva and neutralises plaque acids Plaque acids diffuse out and are neutralised by bicarbonate in saliva Plaque bacteria convert urea to ammonia Urea from saliva diffuses into plaque Ammonia increases plaque pH Calcium phosphate in plaque Dissolves in acid conditions Increases buffering capacity in plaque

26 Saliva and Oral Health Caries Demineralisation-Remineralisation - When the pH value is <5.5 - Calcium (Ca 2+ ) and Phosphate (PO4 3 -) are withdrawn from the dental enamel. Demineralisation - When the pH value is >6.5 - Calcium (Ca 2+ ) and Phosphate (PO4 3 -) migrate back into the dental enamel. Remineralisation H+H+ H+H+ H+H+ H+H+ F-F- F-F- F-F- Ca ++ PO 4 - F-F- F-F- Demineralisation Low pH Ca ++ PO 4 - Remineralisation Increased pH Ca ++ PO 4 - ©Reeves 2014 Ca ++ PO 4 - - A dynamic equilibrium exists between demineralization and remineralisation. - A neutral pH value promotes remineralisation.

27 Saliva and Oral Health Caries Demineralisation- Remineralisation - Demineralisation shifts to remineralisation by the use of fluoridation and saliva activation. Saliva provides the medium for remineralisation. - Supersaturation of saliva with ionic Ca and Pi, can effectively help remineralise incipient caries lesions. - Enhancing remineralization resulting in enamel with a higher Fl content and lower acid solubility. - Fluoride inhibits demineralisation by penetrating and coating enamel crystals to prevent dissolution.

28 Saliva and Oral Health Caries Demineralisation - Remineralisation At a pH value < 5.5-5.7 demineralisation begins. Reversible caries = early enamel lesions - Plaque-coated. - Frequent fall in pH value below 5.5-5.7. - Beginning of demineralisation of the enamel. - White spots; surface “pseudo-intact” Image Courtesy Dr F Goulbourn Irreversible caries = dentine caries - Prolonged acid attack. - No remineralisation. - Established lesion (manifest caries). - Breach of the enamel surface. ©Goulbourn 2012

29 Saliva and Oral Health THE CARIES BALANCE PATHOLOGiCAL FACTORS - Acid producing bacteria - Frequent eating/drinking of fermentable carbohydrates - Subnormal saliva flow and function PROTECTIVE FACTORS - Saliva flow and components- - Fluoride-remineralisation with calcium and phosphate - Antibacterials: chlorhexidine, xylitol CARIESNO CARIES Caries Redrawn from Featherstone BMC Oral Health 2006 6(Suppl 1):S8

30 Saliva and Oral Health Caries Reduction Studies Clinical Caries Studies - Three year study in children with high caries prevalence showed caries-protective benefit of sugar-free gum (Beiswanger et al. 1998)  Three year study, Puerto Rico  N = 1402 subjects, age 8-13  Chewed gum 3 x/day for 20 min after meals  7.9% fewer DMFS in all subjects and 11.0 fewer in high-caries subjects. - Another two year study confirmed caries-protective benefit in lower-caries prevalence population (Szöke et al, 2001)  Two year study, Hungary  n = 547 subjects, age 8-13  Chewed gum 3 x/day for 20 min after meals or no gum  Results show 38.7% reduction in DMFS increment after 2 years INCREMENTAL DMFS Chewing SF gum reduces caries in prospective 2-3 year clinical trials.

31 Saliva and Oral Health Caries Reduction Studies StudyIntervention (n/N)Control (n/N) Reduction of Caries Incidence (%) Möller 1973 Sorbitol gum 3x/day after meals. 161/313No gum. 152/313 10% Glass 1983 Sorbitol gum 2x/day. 269/540No gum. 271/540 2% Kandelman 1990 15% Xylitol gum 90/274No gum. 97/274 61% Kandelman 199065% Xylitol gum 87/274 No gum. 97/274 66% Mäkinen 1995a Sorbitol gum pellets 2x1.3g, 5x/day 129/1135 No gum. 121/1135 17% Mäkinen 1995a 3:2 xylitol/sorbitol pellets, 5x/day 120/1135No gum. 121/1135 44% Mäkinen 1996 Sorbitol stick, 1, 5x/day. 63/471 No gum. 86/471 28% Beiswanger 1998 Sorbitol gum, 3x/day after meals. High risk subjects, intention to treat, 607/1256 No gum. 649/1256 12% Szöke 2001 Sorbitol stick, 3x/day after meals. Including white spots, 269/547 No gum. 278/547 33% Peng 2004 Sorbitol/xylitol/carbamide gum, 4x/day. 363/733 No gum. 370/733 42% Machiulskiene 2001 Sorbitol gum, 5x/day after meals. 68/432 No gum. 80/320 25% Tabulated Summary of Data from Pertinent Human Intervention Studies

32 Saliva and Oral Health Caries Reduction Studies Caries Reduction and Gum - Conclusions -Multiple studies support the anti-caries benefits of sugar-free gum chewed after eating. -The majority showed reductions in the range 20-60%. -Systematic reviews have also supported this position. (eg Mickenautsch et al, 2007; Deshpande and Jadad, 2008) - Studies have been reviewed by expert panels resulting in supporting reviews and statements from regulatory and authoritative bodies (FDA, FDI, ADA, EFSA, etc).

33 Saliva and Oral Health Erosion The loss of hard tissue as a result of direct decalcification from acids of non bacterial origin. ©Image Courtesy Dr F Goulbourn

34 Saliva and Oral Health Erosion Sources Extrinsic -Acidic foods (pH < 5)* -Acidic medications (pH < 5) -Diet (e.g., frequent acidic food/drink intake. -Particularly in the presence lower saliva flow. - Environmental factors (e.g., occupational exposure to acids) * Exception: Yogurt (pH = 4) is not erosive. Intrinsic -Gastroesophageal reflux (GERD:backflow of gastric acid into the oral cavity). -Vomiting due to: -Chronic alcohol abuse -Bulimia - Central nervous disorders

35 Saliva and Oral Health Erosion Sources Often seen in those striving for a healthy lifestyle ©Goulbourn 2012

36 Saliva and Oral Health Erosion ESCARCEL Study - Prevalence growing steadily. - Europe has a prevalence rate of 29.4% of young adults having erosive tooth wear. - 41.9% demonstrating dentine hypersensitivity. - The increasing prevalence of dentine hypersensitivity due to: - The longevity of healthy dentition. - More frequent daily dietary acid challenges to the tooth surface. - Tooth wear risk factors: - Associated with frequent acidic food with increased levels of damage. Bourgeois D, et al ;FDI Annual World Dental Congress, 28-31 August 2013, Istanbul, Turkey. Image courtesy Dr F Goulbourn Prevalence ©Goulbourn 2012

37 Saliva and Oral Health Appearance of erosions: - Dish-shaped, shallow, rounded edges. - Molar cupping. - On buccal, palatal or incisal dental surfaces. Progress of erosions: - Pain-free onset. - Initially in dental enamel. - Leads to exposed dentine. - Hypersensitivities. - Erosive wear, abfraction. - Opacity to incisal edges. Erosion Aetiology Image Courtesy Dr F Goulbourn ©Goulbourn 2012

38 Saliva and Oral Health - Exogenous dietary acids occur at much lower pH values in comparison to plaque acids. - Saliva stimulation from chewing gum: - Increases the rate of mouth clearance from acidic food or drink 1. - Stimulates saliva production 2. - Increases levels of bicarbonate and calcium ions in saliva 3. - A ids in more rapid remineralisation of the enamel surface following an acid challenge 4. *Initial study suggests salivary stimulation may help 5. *Direct clinical evidence pending Erosion Remineralisation Sugar free gum may help prevent erosion and erosive tooth wear* 1.Trlolo P et al:J Dent Res 1990:69(1Suppl);136 2.Dawes C et al:Arch Oral Biol 2004;49(8):665-669. 3.Dawes C et al: Arch Oral Biol. 1995;40:699-705. 4.Wefel JS et al:J Dent Res 1989;68(1supp):214. 5. Rios D et al: Caries Res 2006;40:218-23.

39 Saliva and Oral Health Review Medical History -Drugs, medicines. -Conditions: Acid reflux, diabetes, vomiting, heartburn, hiatus hernia, -Autoimmune diseases (e.g. Sjögren’s syndrome), radiotherapy Soft Tissue Examination -Oral hygiene. -Periodontal conditions: BOP, pocketing. -Soft tissue loss: previous periodontal therapy, surgical/non surgical. -Dry/ friable mucus membrane. -Lack of saliva pooling. Hard Tissue Examination -Exposed root surfaces. -Attrition -Erosion -Abfraction -Abrasion -Loss of enamel characteristics : shiny,flat surfaces. -Caries rate: root surface, proximal. -Demineralisation bands. Clinical Assessment Examination

40 Saliva and Oral Health Diet -Acids : Food, drinks and frequency. -Sugars: Added, hidden and frequency. -Timing: Avoid before bed time - reduced salivary flow. Oral Hygiene -Tooth brushing technique, bristle type. -Toothpaste abrasives. -Bacterial acids, plaque scores, demineralisation. Fluoride Exposure -Frequency -Age appropriate fluoridation Saliva -Quality: serous, mucoid, frothy. -Quantity: adequate and reaches all areas of the mouth. -Buffering capacity. Clinical Assessment Examination

41 Saliva and Oral Health Clinical Assessment Risk Assessment Tools Caries

42 Saliva and Oral Health Basic Erosive Wear Examination 0 No surface loss 1 Initial loss of enamel surface texture 2* Distinct defect, hard tissue loss less than 50%of the surface area 3* Hard tissue loss more than 50% of the surface area *Dentine is often involved BEWE: a new scoring system for scientific and clinical needs. Clin Oral Investig. 2008 March; 12(Suppl 1): 65–68. BEWE Index Clinical Assessment Risk Assessment Tools

43 Saliva and Oral Health Chairside Testing 1. Measuring the saliva flow rate (ml/min) Saliva categories Saliva flow rates (ml/min) Normal flow rate 1 - 3 Reduced saliva flow rate 0.5 - 0.8 Mouth dryness (xerostomia) <0.5 2. Consistency Visual inspection Categories Characteristics Strongly increased viscosity Sticky frothy saliva Increased viscosity Frothy bubbly saliva Normal viscosity Watery clear saliva 3. Measuring the buffer capacity The change in color on the test strip is compared with the sample card and this indicates the buffer capacity: Saliva Low Medium High

44 Saliva and Oral Health Recommendations H+H+ H+H+ H+H+ H+H+ F-F- F-F- F-F- Ca ++ PO 4 - F-F- F-F- ©Reeves 2014 Ca ++ PO 4 - - Continuous recall with oral hygiene, caries, gingivitis,bleeding index. - Regular fluoridation building up a stable fluoride reservoir. - Use a less abrasive toothpaste. - Only take acidic medications (pH < 5.7) with water. - Diet with a low erosive potential, e.g., vegetables, milk, hard cheese.

45 Saliva and Oral Health - Chew SFG for 20mins after sugar or acid challenge. - Encourage regular saliva stimulation in between meals. -Chew sugar free gum, to increase the saliva flow rate. - Dental care on the go: chewing sugar free gum can: - Provide mouth clearance - Help prevent plaque accumulation. - Increase saliva buffering capacity. - Decrease plaque pH. - Decrease caries and erosive potential. Recommendations Sugar Free Gum

46 Saliva and Oral Health Conclusions  Saliva is the most important part of the body’s own protective systems for maintaining oral health.  Reduced saliva quantity and quality increase the risk of caries, erosion, xerostomia and interfere with the ecological balance in the mouth.  Informing the patient and activating the saliva’s protective function for the mouth and teeth is the basis of a modern, prevention- oriented treatment strategy.  It has been scientifically proven: saliva stimulation by chewing sugar free gum helps to increase the saliva flow-rate up to tenfold, which can reduce the risk of caries by up to 40%.

47 Saliva and Oral Health Thank you! 47 Thank You!

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