2 toPulpal reactions to caries and dental proceduresoe.pptx

Pulpal reactions to caries and dental prPulpal reactions to caries and dental procedures
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1. Pulpal reactions to caries and dental procedures

2. Access is the first and most important phase of root canal treatment. A well-designed access preparation is essential for a good endodontic result.

3. Coronal pulp Radicular pulp Pulp chamber Pulp horn Orifice Root canal Lateral canal Apical foramen Pulp space morphology

4. Principles of access cavity preparation Outline form. Convenience form. Removal of remaining carious dentin and defective restorations. Toilet of the cavity.

5. Outline form: Established by mechanically projecting the internal anatomy to the external surface. Three factors regulating the outline form: a. Size of pulp chamber: Young patients extensive. Old patient limited.

6. 3- Removal of remaining carious dentin and defective restorations: Reasons of removing caries and defective restorations: Elimination of bacteria. Elimination of discolored tooth structure. Elimination of the possibility of coronal leakage.

7. 4- Toilet of the cavity: All caries, calcified debris and necrotic material should be removed by irrigation from the pulp chamber before radicular preparation is begun to avoid obstruction of the root canals.

8. Surgical operating microscope Loupes

9. Access cavity preparation in anterior teeth Outline form of central and lateral incisors are triangular with the base of the triangle towards the incisal edge and the apex towards the cingulum . Incisal edge Cervical line

10. The bur is positioned in a 45 degree to the long axis of the tooth then advanced to penetrate the pulp chamber. 3

11. Removal of the pulp chamber ( deroofing ) 4

12. Removal of lingual shoulder. 5

13. Premolars Upper oval Lower ovoid

14. Maxillary premolars Buccal canal is located under the buccal cusp tip. Palatal canal is located at the base of the palatal cusp.

15. Initial penetration is made parallel to the long axis of the tooth in the exact center of the central groove 1 1

16. A round bur is used to open into the pulp chamber. The bur will be felt to “drop” when the pulp chamber is reached. 2

17. A round bur is used to deroof the pulp chamber. 4

18. Finishing and flaring of the cavity walls. 5

19. Errors Under extended access cavity Over extended access cavity

20. PERFORATION at the cervical area caused by failure to recognize that the premolar has tilted to the distal. FAILURE to locate the third canal of the maxillary first premolar (6% of the time).

21. Pulpal reactions to caries and dental procedures Pulpal reactions to caries and dental procedures Pulpal reactions to caries and dental procedures Pulpal reactions to caries and dental procedures

22. Errors Under extended access cavity Over extended access cavity

23. Perforation in the furcation area Failure to locate all the canals

24. Crown perforation Root perforation

25. Axioms of pulp anatomy 1- The two orifices of the maxillary first premolars are further to the buccal . 2- The orifices of the mesio-buccal canals in molars are well up under the mesio-buccal cusps and the outline form should be widely extended into the cusp.

26. 3- The orifices of the palatal canal in maxillary molars is not too far to the lingual, but is actually in the center of the mesial half of the tooth 4- The orifices of the disto-buccal canal in maxillary molars is not too far to the disto buccal , but it is almost buccal to the palatal orifice.

27. 5- The orifice of the distal canal in mandibular molars is not too far to the distal, but is actually in the exact center of the tooth 6- The orifice of the mesio -lingual canal in mandibular molars is not too far to the mesio -lingual, but is almost mesial to the distal orifice.

28. 1-Law of centrality: The floor of the pulp chamber is always located in the center of the tooth at the level of the CEJ. 2-Location of CEJ: The distance from the external surface of the clinical crown to the wall of the pulp chamber is the same throughout the circumference of the tooth at the level of the CEJ, making the CEJ is the most consistent repeatable landmark for locating the position of the pulp chamber. Laws of the pulp chamber anatomy