Operating Microscope Improves Negotiation of Second Mesiobuccal Canals in Maxillary Molars

Abstract

This in vitro study investigated the prevalence, location, and pathway of the second mesiobuccal canal (MB-2) in 45 first and second maxillary molars using the operating microscope (OM). Initially location and negotiation of MB-2 were attempted without magnification. Teeth in which MB-2 was not located or could not be negotiated were further explored under OM. Roots where MB-2 could not be negotiated even with OM were cross-sectioned and inspected microscopically. Morphometric measurements were performed to map the location of MB-2. Without magnification an apparent MB-2 orifice was located in 42 teeth and the canal negotiated in 31 (69%). With OM one additional apparent MB-2 orifice was located, and five previously identified canals were negotiated (total 80%). The root cross-sections confirmed the absence of MB-2 in all nine teeth where it was not negotiated. Location of MB-2 varied randomly. In conclusion MB-2 can be negotiated in 80% of maxillary molars, although an orifice is apparent in 96% of the teeth. Ability to negotiate MB-2 is facilitated by OM.

Three-dimensional Analysis of Mesiobuccal Root Canal of Japanese Maxillary First Molar Using Micro-CT

“…However, this method requires preparation by cleaning the contents of root canals with chemicals before dye injection, and may cause events such as insufficient staining due to the remaining contents of root canals, enlargement of the root canals due to the chemicals, and fissures in the extracted teeth due to dryness; therefore, it is presumably difficult to reproduce the original root canal morphology. The assessment of root canals using the smallest file available in actual practice is a very clinical method 8) , since the presence or absence of access to the apex affects the therapeutic success; however, there have been no reports on lateral canals which could not be radiographed with files in place. The classifications by Weine et al 23) , Vertucci 21) , and Sert and Bayirli 19) are excellent for identifying root canal morphology, but do not address the differentiation of the observed structures.…”

Effectiveness of three methods for evaluating root canal anatomy of mandibular incisors

“…Thus, use of dental microscopy was required in order to provide the magnification and intense illumination needed to observe the second canal (16,25). However, even dental microscopy was not efficient in identifying all teeth with two canals, as the number of such teeth identified was substantially higher for tooth-clearing technique.…”

Frequência do quarto canal radicular em primeiros molares superiores tratados endodonticamente: estudo retrospectivo

“…Dos 1ºMS com a presença do quarto canal analisados nesta pesquisa, 77% tiveram o quarto canal instrumentado em todo o comprimento de trabalho. Em um estudo realizado por Görduysus et al 9 (2001), a incidência do orifício do quarto canal foi alta (96%), porém, foram totalmente percorridos e instrumentados em 80%, devido a calcificações e atresias.…”

“…Em estudos realizados in vitro 8,9 , a frequência do quarto canal mostrou-se sempre superior quando se utilizava ultrassom, microscópio clínico, tomografia computadorizada e secção das raízes analisadas. Isso ocorre devido à facilidade em se manusear um elemento dental fora da boca do paciente, sem interferências, com visão direta e aumento de imagem.…”