hypersensitivity of teeth and its management

dentin hypersensitivity/root dentin hypersensitivity its causes,prevalence / Treatment strategies for dentinal hypersensitivity

1. HYPERSENSITIVITY OF TEETH & ITS MANAGEMENT Resource Faculties Dr. Shivalal Sharma Dr. Khushboo Goel Dr. Sajeev Shrestha Dr. Pujan Acharya Presenter Prawin Chandra Kushwaha

2. CONTENTS Definition Prevalence Etiology Theories Vicious cycle of hypersensitivity Symptoms Diagnosis Management of hypersensitivity

3. Dentin Hypersensitivity is “characterized by short, sharp pain arising from exposed dentin in response to stimuli typically thermal, evaporative, tactile, osmotic or chemical stimuli and which cannot be ascribed to any other form of dental defect or pathology.” The international Workshop on Dentin Hypersensitivity(1983) Manifests as a pain induced by cold or hot food, citrus fruits, sweets, dental instruments, contact with brush

4. PREVALANCE 14.3% of all dental patients. Periodontal patients - upto to 72-98% Adults in age group of 20-50 yrs ( P eaks in 30- 40 years ) M ore common in cervical area of facial surface of permanent teeth ( Canines and Premolars commonly involved )

5. ETIOLOGY Scaling and root planing in periodontal therapy Dietary factors: fruit, juice, yoghurt & wines. Acid in dental plaque, gastric reflux Agents in toothpaste like abrasive and surfactant Psychological disorder (bruxism, abnormal clenching habits)

6. Pathological conditions that cause dentinal hypersensitivity Cracked teeth / chipped tooth Leaky restoration margin G ingival recession and Periodontal disease Deep Dentinal Caries Root caries Trauma from occlusion pulpitis

7. Mechanism of pain transmission – theories of dentin hypersensitivity D irect neural stimulation theory F luid/hydrodynamic theory ( most accepted) T ransduction theory

8. Direct innervation theory According to this theory , ‘ nerve fibers present within the dentinal tubules initiates impulses when they are injured and this causes dentinal hypersensitivity’ .

9. T ransduction theory This theory suggests that the odontoblasts or their processes are damaged when external stimuli are applied to exposed dentin. As a result of this they conduct impulses to the nerves in the predentin and underlying pulp from where they proceed to the CNS.

10. Hydrodynamic Theory Proposed by Brannstrom M Most accepted theory Dentin has over 30,000 dentinal tubules /mm2 These are filled with dentinal fluid which is the intracellular fluid of the pulpal connective tissue . Whenever exposed dentin is stimulated by tactile , chemical, thermal or osmotic stimuli there is rapid movement of the dentinal fluid either towards the pulp or outward.

11. This can cause: Direct stimulation of the low threshold A-delta nerve fibers in the pulp. Indirect stimulation of A- delta nerve fibers in the pulp by displacing the odontoblastic cell bodies. Such rapid displacement of the dentinal fluid in thousands of dentinal tubules at the same time produces a cumulative effect and this causes hypersensitivity .

12. Vicious cycle of hypersensitivity hypersensitivity Patient refuses prophylactic measures Increased plaque deposition

13. Symptoms Initial : sharp pain of rapid onset and disappears once the stimulus is removed Severe : long standing –shorter or longer periods of lingering, dull aching pain may be provoked Even a minimal contact with the toothbrush may elicit intense pain

14. Diagnosis History of nature, intensity, duration and frequency of pain History- periodontal treatment, diet ary habits . History of pain during brushing, h/o of trauma, diurnal variation of pain. physical findings of tooth/teeth are essential to rule out caries , cracked tooth , pulpitis , non vital tooth Rule out any other cause of sharp pain.

15. Clinical examination Patient often directs the operator toward the hypersensitive area may be located by gentle exploration with probe or cold air (due to root surface exposure) T ender on percussion Clinical findings like attrition , fractured cusp Gingival recession /loss of attachment Thermal test Electrical test Radiography

16. Methods of measuring dental hypersensitivity Subjective Assessment Verbal rating scale is a simple descriptive pain scale which includes the following: 0 – No discomfort 1 – Mild discomfort 2 – Marked discomfort 3 – Marked discomfort that lasted for more than 10 seconds Gillam and new Man (1993)

17. Objective Assessment Mechanical / Tactile stimuli 1. Explorer probe 2. Mechanical pressure stimulation 3. Yeaple Probe

18. MANAGEMENT Stepwise approach: First Step: confirmation of diagnosis. Second Step: consider etiology and behavior Third Step: management strategies . Two major groups of products are used to treat dentinal hypersensitivity: 1)those that block and occlude dentinal tubules 2)those that interfere with the transmission of neural impulses.

19. Treatment strategies for dentinal hypersensitivity 1. Nerve desensitization Potassium nitrate 2. Anti-inflammatory agents Corticosteroids 3 Cover or plugging dentinal tubules a. Plugging (sclerosing) dentinal tubules b. Dentine sealers c. Periodontal soft tissue grafting d. Crown placement/restorative material e. Lasers

20. a. Plugging (sclerosing) dentinal tubules Ions/salts Calcium hydroxide Ferrous oxide Potassium oxalate Sodium monofluorophosphate Sodium fluoride Sodium fluoride/stannous fluoride combination Stannous fluoride Strontium chloride Protein precipitants Formaldehyde Glutaraldehyde Silver nitrate Strontium chloride hexahydrate Casein phosphopeptides Burnishing Fluoride iontophoresis

21. b. Dentine sealers Glass ionomer cements Composites Resins Varnishes Sealants Methyl methacrylate

22. Dietary advice: citrus fruits , apple or any other food or drink that acidic in nature should be avoided . Plaque control Severe symptoms: use those agents which block the tubular opening. In very severe case , remedy is achieved by pulpectomy or root canal filling.

23. Information to patient Possibility of root hypersensitivity before treatment is undertaken How to cope with the problem: Hypersensitivity is inevitable if calculus and plaque buried in the root is to be removed. Disappears slowly over a few weeks. Plaque control is important for its reduction. Desensitizing agent should be used continuously for at least 2 weeks.

24. Desensitizing agent Can be applied : 1.By the patient at home 2.By the dentist or hygienist in the dental office. Clinical evaluation of different agent is difficult because Measuring and comparing pain between different persons is difficult. H y persensitivity disappears by itself after a time and, Desensitizing agents usually take a few weeks to act.

25. Agent used at home Desensitizing toothpastes/dentifrices: The following dentifrices have been approved by the American Dental Association for desensitizing purposes: I) Sensodyne II) Thermodent which contain strontium chloride . Denquel , and Promise , which contain potassium n itrate . P rotect which contains sodium citrate

26. ACTIONS Potassium nitrate 5%- Blocks sensory nerve activity at pulpal end of tubules by altering the excitability of nerves Strontium chloride 0.4%- combines with phosphate in dentinal fluid , strontium phosphate crystals then binds to tubular matrix thus leading gradual reduction of tubular radius and finally leads to closure. sodium citrate : Act by precipitation of crystalline salt on dentinal surface → block the dentinal tubule

27. Agents used at dental office 1)Topically applied desensitizing agents:- Fluoride( sod.fluoride , stannous fluoride) :- possibly by precipitation of insoluble calcium fluoride within the tubules. Which blocks fluid movement within the dentin Potassium nitrate :- potassium ions do reduce nerve excitability

28. Oxalate :- Oxalate products reduce dentin permeability and occlude tubules more consistently Currently , potassium and ferric oxalate solutions are the preferred a g ents . They form insoluble calcium oxalate crystals that occlude the dentinal tubules and prevent fluid movement. ferric oxalate under the name Sensodyne Sealant. Calcium phosphates :- Calcium phosphates occlude dentinal tubules in vitro and decrease in vitro dentin permeability by 85%

29. 2) Placement of restorations : Glass ionomer or a composite resin restoration may be placed to replace the lost tooth structure and seal the exposed dentin . 3) Ionto-phoresis This procedure uses electricity to enhance diffusion of ions into the tissues. Dental iontophoresis is used most often in conjunction with fluoride pastes or solutions ( 2% sodium fluoride)

30. A 2% sodium fluoride is applied on the exposed dentin and this is transferred deep into the dentin on activation of the unit.

31. 4)Lasers Recently , attempts have been made to improve the success and longevity of these treatment using lasers. Low- level laser “melting” of the dentin surface appears to seal dentinal tubules without damage to the pulp. Finally , in a combined treatment modality, the Nd:YAG laser has been used to congeal fluoride varnish on root surfaces.

32. This in vitro study demonstrated that the laser treated fluoride varnish resisted removal by electric tooth-brushing, with 90% of tubules remaining blocked while in the controls (no laser treatment) the fluoride varnish was almost completely brushed away. F urther research is still on progression.

33. Suggestions for patients: Avoid using large amounts of dentifrice or reapplying it during brushing. Avoid medium- or hard-bristle toothbrushes. Avoid brushing teeth immediately after ingesting acidic foods. Avoid over brushing with excessive pressure or for an extended period of time. Avoid excessive flossing or improper use of other interproximal cleaning devices. Avoid “picking” or scratching at the gumline or using toothpicks inappropriately.

34. Suggestions for professionals: Avoid over instrumenting the root surfaces during scaling and root planing , particularly in the cervical area of the tooth. Avoid over polishing exposed dentin during stain removal. Avoid violating the biologic width when placing crown margins causing subsequent recession. Avoid burning the gingival tissues during in-office tooth whitening or bleaching procedures.

35. SUMMARY

36. R EFERENCES Dentinal hypersensitivity: a review Australian Dental Journal 2006;51:3.