بررسي مورفولوژي كانال ريشه دندان پرمولر دوم فك بالا

ROOT CANAL MORPHOLOGY OF HUMAN MAXILLARY SECOND PREMOLAR

BACKGROUND AND OBJECTIVE: One of the main reasons of root canal treatment failure specially in maxillary second premolars is missed canals. Since this tooth has various number and canal configuration, it was decided to show the root canal morphology in this tooth in an in vitro study using dye penetration, in order to increase the knowledge of dentists with the morphology of the maxillary second premolars to decrease the root canal treatment failures. METHODS: In an in vitro experimental study a number of 100 extracted human maxillary second premolars from patients referred to the dental medical services were chosen randomly. The teeth were decalcified using the clearing techniques. Then the canals were colored using Indian ink, in order to study the number of roots, canal configuration and the location of the apical foramen according to Vertucciʹs root canal classification. FINDINGS: Results were analyzed under direct sunlight and according to Vertucciʹs root canal classification. Among the 100 examined teeth: 11% Type I, 48% Type II, 30% Type IV, 3% Type V, 8% Type VI, Type III, VII and VIII were not observed. 98% of the examined teeth had one root and 2% had two roots. 41% were with two foramina and 59% with one foramen. 78% of maxillary second premolars had two canals. CONCLUSION: Before deciding to perform root canal treatment gaining a good knowledge of the morphology of the pulp chamber is essential. According to a high prevalence of two canals in our study, it is necessary to look for an extra canal during the access cavity preparation. Either directly or by using angled radiographs.