Thickness of dentine in mesial roots of mandibular molars with different lengths

Abstract

There was a significant difference in the minimum thickness of the distal (furcal) root wall of the mesiobuccal canal of mandibular first molars 2 mm below the furcation between group I (long) and group III (short) teeth. The thinnest walls were found in the longest teeth. The deepest concavities in the distal (furcal) walls of the mesial roots were found in the longest roots.

Validation of cone beam computed tomography as a clinical imaging method for dentin thickness measurement in the danger zone of mandibular molars

“…Therefore, the present study compared the measurements performed on CBCT images to stereomicroscope images (direct measurement). The measurements found in this study corroborate the results of other studies using diverse methodologies to assess the danger zone 2 mm below furcation area 13,16,30,31 . The absence of differences between the two methods suggests that CBCT is an imaging diagnostic tool that may be used clinically (in patients), allowing professionals to control the risk of tearing due to excessive wear during root canal preparation.…”

“…Teeth were provided by a tooth bank of the same institution. The sample size was estimated considering the standard deviation reported for the dentine thickness in mesial roots of mandibular molars 13 , the voxel size used (0.25 mm), a significance level of 5%, and a power test of 80%.…”

“…Ten permanent first mandibular molars with complete root formation, measuring from 19 to 21 mm length 13 , without endodontic treatment, root fractures, and/or perforations were used. After coronal opening, the working length was determined reducing 1 mm after the file tip became visible at the apical foramen of the mesio buccal (MB) canal.…”

“…Additionally, it promotes greater removal of contamination at the cervical third, greater penetration of the irrigating solution, lower possibility of steps formation and fracture of the endodontic instrument, lower extrusion of necrotic debris and micro-organisms to the apex, and more precise determination of the initial apical instrument length 7,8 . Several methods have been used to evaluate RCS, which could assess the risk of tearing and perforation at the furcation area, such as histological sections 9 , serial sections 10 , clearing 11 , scanning electron microscopy 12 , stereomicroscope 13 , radiographs 14 , silicone impressions of the root canal 15 , CBCT 16,17 , and micro computed tomography (micro--CT) 18 . Among clinical methods, which can be used in vivo, CBCT is a promising one, since it allows tridimensional evaluation 19,20 .…”

Análise, através de tomografia computadorizada, do preparo promovido pelo alargamento cervical em molares inferiores e sua influência na determinação do diâmetro anatômico apical por meio de MEV

“…Os autores concluíram que os instrumentos utilizados são seguros e ____________________________________________________Revista da Literatura -41 -não promoveram danos extensos à parede distal das raízes mesiais de molares inferiores. SAUÁIA et al (2010) avaliaram, por meio de um sistema de muflas a região 2mm abaixo da furca de raízes mesiais de molares inferiores em relação à espessura mínima de dentina. As raízes foram divididas em três grupos de acordo com o comprimento dental, G1 longo (24.14 mm ± 0.85), G2 médio (22.10 mm ± 0.65) e G3 curto (19.97 mm ± 0.75).…”