A Comparison On The Anatomy Of Maxillary First Permanent Molars Between Nanning And Vientiane People

Objective: The aim of this study was to compare the anatomy morphologyof maxillary first permanent molars between Nanning and Vientiane resident andto provide scientific basis for clinical endodontic treatment.Methods: Forty-four extracted maxillary first permanent molars werecollected from Nanning and Vientiane and divided into two groups. All teethwere measured by electronic digital caliper. The dental operating microscopewas used to observe the shape of pulp-chamber floor. The clearing techniquewas used to investigate the amount and the location of apical foramen and thecanal morphology of mesiobuccal root. The data was analyzed using SPSS19.0statistical package.Result: In Nanning and Vientiane people, the average length of crown were7.21mm、6.40mm,the root were11.52mm、12.00mm and the over length of toothwere18.73mm、18.40mm respectively. The average length of crown in Nanningwas higher than it in Vientiane, and the difference between two groups wasstatistically significant (P<0.05).The main shape of pulp-chamber floor of themaxillary first molars was type “7”and “Y” and there was no statistical difference between two groups (P>0.05).The incidence of more than two rootholes of the mesiobuccal root in Nanning and Vientiane were77%and59%respectively (P<0.05). The percentage of root holes which located in their apiceswere about44%and43%respectively (P>0.05). The main type of classificationof root canal with the maxillary first permanent molars in Nanning were type I、IV and V,the proportion were about32%、22.7%and18%respectively. Thedata of Vientiane were type I、II、IV, and the ratio were about27%、32%and27%respectively. There was statistical difference between two groups (P<0.05).Conclusion:1、The main shape of pulp-chamber floor of maxillary firstpermanent molars was “Y”and“7” in Nanning and Vientiane people.2、Theamount in apical foramen of mesiobuccal root of maxillary first permanentmolars in Nanning was more than the amount of it in Vientiane.3、Most of theroot holes of maxillary first permanent molars were located in none-apicalzone.4、The incidence of two canals in the mesiobuccal root of the maxillaryfirst molars was high in both two groups.