Incidence and location of the second mesiobuccal canal in Mongolian maxillary molars

YIN Xing; XU Yong-jun; ZHAO Lian-ying; HASI Mu-ren

Abstract：AIM:To study the incidence and the orifice location of the second mesiobuccal canal (MB2)in maxillary molars and to analyze the relationship between MB2 orifice and other canal orifices of the molars.METH-ODS:55 extracted maxillary first molars and 61 second molars were collected,then a rhombus shaped improved sloping mesiobucca access was prepared for probing MB2,the parameters were measured and calculated for locating MB2 orifice. RESULTS:The incidence of MB2 in maxillary first and second molars were 67.27% and 39.34% respectively (P<0.05).The distances(mm)between the orifices of MB2 and MB of maxillary first and second molars were 1.66 ± 0.61 and 1.43 ±0.48,between MB2 and P 3.58 ±0.84 mm and 3.47 ±0.61 mm,between MB and P 4.85 ±0.80 mm and 4.54 ±0.5 1 mm,respectively.The vertical distances from MB2 to MB-P line of maxillary first and second molars were 0.79 ±0.45 mm and 0.68 ±0.41 mm,the angles between MB-P and MB-MB2 line were (32.30 ±19.18)°and (33.12 ±22.56)°,respectively,all the parameters were not statistically different betwwen the first and second molars (P>0.05).CONCLUTION:Mongolian maxillary first and second molars have high incidence of MB2.The MB2 ori-fice of Mongolian maxillary molars is located in 20-50°and less than 1 mm mesially to the MB-P line,less than 2 mm palatally from the MB orifice and in 2~4 mm mesiobuccally from the P orifice.