Aim: To identify the incidence of accidental pulp exposure during the preparation of vital abutment tooth for porcelainfused- to-metal (PFM) fixed prosthesis when prepared by undergraduate students.
Materials and methods: A cohort study was conducted on 471 teeth, which were prepared to received PFM fixed partial denture, in patients between the age group of 20-40 years for 72 months. All the teeth were vital and healthy periodontally; preoperative radiographs were recorded. Measurements were taken from cone beam computed tomography (CBCT) scans of human extracted teeth for reference of the pulpal depths. Teeth with endodontic pulp exposure were documented and referred to the endodontic department.
Results: In multivariate regression, when all variables were simultaneously considered and accounted for, tooth factors (arch and whether the tooth is anterior or posterior) and the distance between pulpal wall and cusp tip were significantly associated with odds of exposure (p = 0.006, 0.03 and < 0.0001). Maxillary and anterior were associated with higher odds of lateral exposure compared to mandibular and posterior teeth (OR = 10.34 and 3.53).
Conclusion: The present study draws the attention of the clinician towards the detrimental effect of tooth preparation on the vital pulp. The study concluded that maxillar and anterior teeth exposure has higher odds than mandibular and posterior teeth.
Clinical significance: The undergraduate students must be trained to be extra careful while preparation of anterior and maxillary teeth for fixed partial dentures (FPD) to avoid pulpal exposure.
Hebel K, Gajjar R, Hofstede T. Single-tooth replacement: bridge vs. implant-supported restoration. J Can Dent Assoc 2000;66(8):435-438.
Motta AB, Pereira LC, Da Cunha AR, Duda FP. All ceramic and porcelain fused to metal fixed partial dentures: a comparative study by 2D finite element analyses. J App Oral Sci 2007;15(5):399-405.
Hemmings K, Harrington Z. Replacement of missing teeth with fixed prostheses. Dental Update London 2004;31(3): 137-141.
Özcan M. Fracture reasons in ceramic fused to metal restorationn. J Oral Rehab 2003;30(3):265-269.
Anusavice KJ. Standardizing failure, success, and survival decisions in clinical studies of ceramic and metal–ceramic fixed dental prostheses. Dent Mater 2012;28(1):102-111.
Goodacre CJ, Bernal G, Rungcharassaeng K, Kan JY. Clinical complications in fixed prosthodontics. J Prosthet Dent 2003;90(1):31-41.
Cheung GSP, Lai SCN, Ng RPY. Fate of vital pulps beneath a metal-ceramic crown or a bridge retainer. Int End J 2005;38(8):521-30.
Christensen GJ. How to kill a tooth. J Am Dent Assoc 2005; 136(12): 1711.
Christensen GJ. Avoiding pulpal death during fixed prosthodontic procedures. J Am Dent Assoc 2002;133(11):1563-1564.
Borelli B, Sorrentino R, Goracci C, Zarone F, Ferrari M. In vitro analysis of residual tooth structure of maxillary anterior teeth after different prosthetic finish line preparations for full-coverage single crowns. J Oral Sci 2013;55(1):79-84.
Davis GR, Tayeb RA, Seymour KG, Cherukara GP. Quantification of residual dentine thickness following crown preparation. J Dent 2012;40(7):571-576.
Whitworth JM, Walls AWG, Wassell RW. Crowns and extracoronal restorations: endodontic considerations: the pulp, the root-treated tooth and the crown. Br Dent J 2002;192(6): 315-327.
Lee MM, Brian JR, Aura MT, Shah R, Musikant B, Deutsch A. Morphological measurements of anatomic landmarks in pulp chambers of human anterior teeth. J Endod 2007;33(2): 129-131.
Deutsch AS, Musikant BL, Gu S, Isidro M. Morphological measurements of anatomic landmarks in pulp chambers of human maxillary furcated bicuspids. J Endod 2005;31(8):570- 573.
Deutsch AS, Musikant BL. Morphological measurements of anatomic landmarks in human maxillary and mandibular molar pulp chambers. J Endod 2004;30(6):388-390.
Velmurugan N, Venkateshbabu N, Abarajithan M, Kandaswamy D. Evaluation of the pulp chamber size of human maxillary first molars: An institution based in vitro study. Ind J Dent Res 2008;19(2):92-94.
Ohashi Y. Research related to anterior abutment teeth of fixed partial denture. Shikagakuho. 1968;68:726.
Sherrard JF, Rossouw PE, Benson BW, Carrillo R, Buschang PH. Accuracy and reliability of tooth and root lengths measured on cone-beam computed tomographs. Am J Orthod- Dentofac Orthop 2010;137(4):S100-S108.
Bidar M, Madani AS, Mohtasham N, Vardkar M, Jafarzadeh H. The Effect of Full Crown Preparation on Normal and Inflamed Pulp Tissue: An Animal Study. J Dent Mater Tech 2013;2(1):29-33.
Abeer S, Al-Khreisat AS. Early endodontic complications following fixed prosthodontic restorations. J Royal Med Serv 2010;17: 36-41.
Gumus HO, Kocaagaoglu HH, Aslan T, Albayrak H, Sagsen B. Prevalence of pulp exposures during tooth preparation for fixed prosthetics. Eur J Prosthod 2014;2(2):48-52.