Purpose: to propose further investigation, with the same criteria, the incidence of MB2 canals in maxillary molars in 3-yr period with result successively treating and retreating these teeth
N= Total of 5616 Max molars (1st & 2nd ) treated for over 5 years
Material & Methods:
•Mb2: Canal had to be negotiated to full WL or within 5 mm from apex
Most highlighted Results:
- 1st Molar 58% (NSRCT). 66% (Retreatment) had MB 2.
- 2nd Molar 34% (NSRCT), 40% (Retreatment) had MB2
The significant difference in the incidence of a MB2 canal between initial treatments and retreatments suggests that failure to find and treat existing MB2 canals will decrease the long-term prognosis .