Pulp protection

Basics of pulp protection and materials

1. PULP PROTECTION DEPARTMENT OF CONSERVATIVE DENTISTRY AND ENDODONTICS THIRD YEAR SHUBHAM PARMAR

2. INTRODUCTION Basic goal of conservative dentistry is to preserve the health of dental pulp Dental pulp is a soft connective tissue of mesenchymal origin present within the pulp chamber and root canals of teeth Pulp protection is important as most restorative materials themselves are not protective to pulp Pulp is subjected to various insults due to caries, materials and operative procedures Pulp protection also helps pulp recovery in case of deep defects For this reason the use of pulp protecting agents such as sealers, liners and bases is important

3. PULPAL IRRITANTS Disease process itself – Caries, trauma, attrition, abrasion Mechanical Irritation – Excessive heat during cavity preparation Chemical irritation – Phosphoric acid of zinc phosphate cement Thermal Irritation – Due to heat conducted by metallic restorations Microleakage

4. REMAINING DENTIN THICKNESS (RDT) Dentine is the best insulator for pulp Better to conserve as much as dentine as possible Therefore the amount of RDT is the most important factor in deciding the best method of pulp protection RDT Effect of toxic substances on pulp 0.5mm 25% 1mm 10% 2mm Minimal or nil

5. PULP PROTECTION AGENTS Pulp protection agents are selected on the basis of – The restorative material being used The RDT between the pulp and the pulpal or axial walls of the final tooth preparation PULP PROTECTION AGENTS INCLUDE : Cavity Sealers – Varnish and Bonding Agents Cavity Liners Cavity Bases

6. CAVITY SEALERS These are materials that are applied to walls of prepared tooth and seal the interface between the tooth and the restoration Liners are used to seal the dentinal tubules Do not possess mechanical strength nor provide any significant thermal insulation CAVITY VARNISH – Varnish his a natural gum or a synthetic resin dissolved in an organic solvent The organic solvent evaporates leaving behind a protective film when applied to the tooth Commonly used in amalgam restorations Contraindicated under GIC restorations Thickness if 2-5µm

7. CAVITY SEALERS RESIN BONDING AGENTS- currently accepted method of bonding composite to tooth structure Also help in cavity sealing

8. CAVITY LINERS Cement coating of minimal thickness which serve as a physical barrier to bacteria Applied only to the dentinal walls of preparation close to the pulp Traditionally liners were used to medicate pulp in deep preparations Liners are more fluid than bases, and used in thin layers (approximately 0.5 mm) Currently used liners – Calcium Hydroxide, Glass Ionomer Cement

9. CAVITY LINERS CALCIUM HYDROXIDE is used as a liner for the following reasons Pulpal compatibility Stimulate reparative dentine formation Antibacterial activity Disadvantages of Calcium Hydroxide Low strength High solubility Undergoes softening

10. CAVITY LINERS GLASS IONOMER CEMENT Advantages Fluoride release Chemical adhesion to tooth structure Biocompatible

11. CAVITY BASES Used to replace missing dentine Block out undercut for indirect restorations Thickness usually 0.5-2mm Applied on pulpal and axial walls of cavity Provide thermal protection to pulp Materials used – Zinc Phosphate Cement Zinc polycarboxylate Glass ionomer cement (Type III)

12. CAVITY BASES Zinc Phosphate Traditionally material of choice under metallic restorations Superior physical properties Excellent thermal insulation Zinc Polycarboxylate More biocompatible than Zinc Phosphate Adhesive to tooth structure Glass Ionomer Most popular base Fluoride releasing property Can be used under a variety of materials

13. GUIDELINES FOR PLACEMENT OF PULP PROTECTING AGENT RESTORATION SHALLOW CAVITY MODERATELY DEEP CAVITY DEEP CAVITY Amalgam Varnish/Dentine bonding agent Base Calcium Hydroxide Liner + Base Composite Resin Dentine bonding Agent Dentine Bonding agent Calcium Hydroxide liner + GIC base Glass Ionomer Cement - - Calcium Hydroxide liner Cast gold inlays and onlays Luting cement Base and Luting Cement Calcium Hydroxide liner, base and luting cement Ceramic inlays and onlays Dentine bonding agent and resin cement Dentine bonding agent and resin cement Calcium hydroxide liner+ GIC base+ dentine bonding agent

14. INDIRECT PULP CAPPING A procedure wherein small amount of carious dentine is retained in deep areas of cavity to avoid pulp exposure, followed by placement of a suitable medicament and restorative material that seals of the carious dentine and encourages pulp recovery -Ingle

15. INDIRECT PULP CAPPING OBJECTIVES OF INDIRECT PULP CAPPING Given by Eidelman in 1965 Arresting the carious process Promoting dentine sclerosis Stimulating tertiary dentine formation Remineralization of carious dentine

16. INDIRECT PULP CAPPING INDICATIONS Deep carious lesion near the pulp tissue but not involving it No mobility of tooth No history of spontaneous toothache No tenderness to percussion No radiographic evidence of pulp pathology No root resorption or radicular disease should be present radiographically

17. INDIRECT PULP CAPPING CONTRINDICATIONS Sharp penetrating pain Spontaneous pain Night pain Mobility Discoloured tooth Break in lamina dura Widened PDL space

18. DIRECT PULP CAPPING Placement of a medicament or non medicament material on a pulp that has been exposed in course of excavating the last portion of deep dentinal caries or as a result of trauma -Kopel 1992

19. DIRECT PULP CAPPING OBJECTIVES Create new dentine in area of exposed pulp Healing of pulp RATIONALE – To achieve biologic closure of exposure site by formation of dentine bridge

20. DIRECT PULP CAPPING INDICATIONS Small mechanical exposure Asymptomatic vital primary teeth Bright red haemorrhage Easily controlled Pin point exposure CONTRINDICATIONS Night pain Spontaneous pain Mobility Periapical lesion Excessive haemorrhage Root resorption

21. References Sturvedant’s Art And Science Of Operative Dentistry 6e Clinical Operative Dentistry Principles And Practice By Ramya Raghu 2e Textbook Of Paediatric Dentistry By Nikhil Marwah 4e Google Images