A cone‐beam computed tomography study of the anatomical relationships between mandibular teeth and the mandibular canal, with a review of the current literature

Abstract

The purpose of this study was to evaluate age- and sex-related changes in the anatomical relationships between the roots of the molars and premolars and the mandibular canal using cone-beam computed tomography (CBCT) images. A total of 243 patients (116 males, 127 females) aged 16-83 years for whom previous CBCT scans were available were enrolled in this study. The patients were subcategorized by sex and age (Group I, <21 years; Group II, 21-40 years; and Group III, >40 years). The distances between the mandibular canal and the molars and premolars were measured. The mandibular canal was significantly closer to the root apices of the second and third molars than to the apices of other evaluated teeth (p < 0.05). All measurements were significantly higher in male than in female subjects (p < 0.05). Group I subjects exhibited significantly shorter distances between the mandibular canal and root apices of the first and second premolars, and the molars, than those of Group II and III subjects (p < 0.05). Direct contact relationships were found in 1.6%, 3.3%, 3.3%, 16%, and 32.2% of teeth (running from the first premolar to the third molar, respectively). Age and sex influenced the anatomical relationships between mandibular teeth and the mandibular canal, and these should be considered when planning endodontic and surgical procedures to avoid potential nerve injury.

An analysis of the first and second mandibular molar roots proximity to the inferior alveolar canal and cortical plates using cone beam computed tomography among the Saudi population

“…In the current study, we found that the distance from the root apices to the IAC increased, moving anteriorly from the distal root of the second molar to the mesial root of the first molar. This result is in agreement with that of Aksoy et al,22 who examined the proximity of mandibular teeth to the IAC and found that the second molar is significantly closer to the IAC compared to the first molar and premolars. They also found that the second molar is in direct contact with IAC in 16% of cases, whereas only 3.3% of the first molars were in contact with the IAC.…”

“…This could possibly be explained by our sample age distribution, in which most of our subjects (45 subjects, 75%) were younger than 30 years. Previous studies have demonstrated that age affects the proximity of the IAC to the roots of the mandibular teeth, with younger patients having shorter distances between the teeth and IAC 14,22-24. An increase in this distance with age is likely due to the fact that the craniofacial complex continuously changes throughout life 22.…”

Сross-sectional anatomic study of direct positional relationships between mandibular canal and roots of posterior teeth using cone beam computed tomography

“…According to our data, the roots of 69 second molars (33.8% of the total number of the second molars) in 43 cases (20 women and 23 men) were radiographically in direct contact with the MC. The incidence was twice as high as the data given by Bürklein et al, 3 and Aksoy et al, 5 which showed the direct contact of roots with the canal in 15.2% and 16% of the second molars respectively. They considered that their investigation was the first study reporting the relatively high incidence of the direct contact between the root apices with the mandibular canal.…”

“…According to our data, the roots of 9.3% of the second premolars were in direct contact with the upper wall of the mandibular canal. Direct communication between second premolar and the MC was found in 3.2% of teeth by Bürklein et al, 3 and in 3.3% of teeth by Aksoy et al 5 Individual variations in the position of the mandibular canal relatively to the roots were assessed in the present study. The canal can be located below the roots, on the buccal or lingual side.…”

“…3,4 The proximity of the IAN to the roots of the lower molars and premolars is of great clinical relevance, particularly when performing invasive surgical procedures and during conventional root canal therapy. 5 Inferior alveolar nerve damage may result from the endodontic treatment of mandibular molars and premolars and is a consequence of the chemical, mechanical or thermal irritation. 6 A neurotoxic effect could be potentially caused by sodium hypochlorite, used for chemical disinfection of root canals, or paraformaldehyde-containing obturation materials.…”