Brazil CBCT study - 86-91% MB2 PROVIDED dealing with a three rooted molar
Table 1. The Total Number of Teeth, Teeth with 3 Roots, and the Presence/Absence of MB2 Canals in 3-rooted First and Second Maxillary Molars
|Teeth with 3 roots|
|Right maxillary first molars||79||79||68 (86.1)||11 (13.9)|
|Left maxillary first molars||79||78||71 (91.0)||7 (8.9)|
|Right maxillary second molars||94||88||77 (87.5)||11 (12.5)|
|Left maxillary second molars||91||87||69 (79.3)||18 (20.6)|
|Total||343||332||285 (85.8)||47 (14.1)|
Table 2. The Prevalence of MB2 Canals According to Root Third Assuming have an MB2 (obviously)
|Right maxillary first molars||68 (100)||65 (95.6)||53 (77.9)|
|Left maxillary first molars||71 (100)||68 (95.8)||54 (76.0)|
|Right maxillary second molars||77 (100)||75 (97.4)||51 (66.2)|
|Left maxillary second molars||69 (100)||64 (92.7)||47 (68.1)|
8x scope 80% MB2 and 1% MB3 more of an isthmus study
|This and the following photo are why I think there is so much variance in % of MB2 "found" in studies. Is it a fin, an isthmus, or an MB2?|
|So are the first and third ones MB2? or figure eight shaped single canals?|
Jordan study 63% under 3.5x and 57% naked eye. They also state in this study that max first molars have highest failure rate. I am of opinion this is low as 3.5x is not a high mag. I use 6x for everything and have used 2.5, 22.214.171.124, and 6.0 in my career and can say that the jump from 3.5 to 4.5 made a difference for me. Here is a study proving increase in mag increases ability to locate MB2.
Endo program 70% - The results of this study demonstrate that it is imperative for any dentist performing root canal therapy on maxillary first molars to examine carefully the pulpal floor to locate all canals, especially the second mesiobuccal canal.
Coronal half microscope 1990 95% - 54% accessed with hand instruments, 32% with "bur" (seems something similar to munce) and 10% with scope. Shows better techniques and equipment result in more found
Multiple methods 2009 67% have MB2 and of those 65.30% exhibited 1 foramen
Korean Population CBCT study 64% MB2 1.25% DB2 .25% single root and fused .73%
Hartwell and Bellizzi in vivo 1982 "A discrepancy was observed when 4 canal maxillary molar obturation was compared with the in vitro studies. Access prep should be reevaluated to facilitate the search and location of the 4th canal in maxillary molars. It is almost axiomatic to accept the fact the root canal system of the MB root of the max molars frequently have more than one canal." BINGO!!!