Age-related changes in the pulp chamber of maxillary and mandibular molars on cone-beam computed tomography images

Abstract Background Globally, the need for an accurate and valid method for age estimation in adults still exists. The aging process is associated with secondary dentine deposition that reduces the volume of teeth pulp. Therefore, dental age could be recognized from the volume of pulp cavity. The aim of this study was to assess the accuracy and validity of pulp chamber/crown volume ratio of maxillary and mandibular canines in estimating age using cone beam computed tomography (CBCT) images in a sample of the Egyptian population. Results There were significant strong negative correlations between age and each of the maxillary pulp chamber volume (PCV), mandibular PCV, maxillary pulp chamber/crown volume (PCV/CV) ratio, and mandibular PCV/CV ratio (p < 0.001). Furthermore, no significant differences were detected between both sexes regarding the mean maxillary and mandibular PCV and PCV/CV ratios (p > 0.05). The best fit regression model for age prediction was as follows: age (years) = 70.21 − 784.0x maxillary PCV/CV ratio − 1.66x maxillary PCV. The proposed model showed good power of prediction (R2 adjusted = 0.951). Additionally, the model was validated on an independent sample of 100 CBCT images with a root mean squared error (RMSE) of 2.86 years. Conclusion The obtained valid regression formula in this study can serve as a reliable tool for age estimation in Egyptians. This formula should be further validated on a larger sample size of the Egyptian population that considers more steady age distribution.

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Cone-beam Computed Tomography Investigation of Middle Mesial Canals and Isthmuses in Mandibular First Molars in a Chinese Population

10.21203/rs.2.9841/v1 ◽

2019 ◽

Author(s):

Shuaimei Xu ◽

Junfeng Dao ◽

Zhongjun Liu ◽

Zhiyong Zhang ◽

Yu Lu ◽

...

Keyword(s):

Computed Tomography ◽

Cone Beam Computed Tomography ◽

Root Canal ◽

Chinese Population ◽

Average Length ◽

Cone Beam ◽

Chinese Populations ◽

Mandibular Molars ◽

Computed Tomography Images ◽

Partial Communication

Abstract Background While there is ample research into the anatomy of mandibular molars, little is known regarding isthmuses and middle mesial (MM) canals in Chinese populations. The goal of this study was to determine the prevalence of MM canals and isthmuses in the mesial root of mandibular first molars using Cone-beam Computed Tomography. Methods Cone-beam Computed Tomography images of 357 mature mandibular first molars were retrospectively analyzed. Data regarding demographics, side of mandible, presence of separated distal-lingual roots, presence of isthmuses and MM canals, and the length of isthmuses in the mesial root were recorded. Results Of these 357 teeth, 209 showed evidence of either complete or partial communication in the mesial root. Of these, 11(3.08%) exhibited true MM canals while 198(55.46%) exhibited isthmuses. Sex or side of mandible was not correlated with the incidence of communication (isthmuses or MM canals) (P> 0.05). However, there was a significant association between the presence of a distal-lingual root and the incidence of such communication (P< 0.05). The average length of isthmuses was 4.26 ± 3.14mm. Conclusions We detected high rates of mandibular molars with isthmuses, which is important as such areas should be identified and cleaned during root canal treatment.

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