Evaluation of postoperative changes in the course of mandibular canals impacted by cystic lesions

Abstract

Background: This study aims to determine the positional alterations in the course of mandibular canal, which were caused by the common cystic lesions in the posterior mandible. Also, the effects of treatment methods on bone formation were evaluated.

Methods: We designed a retrospective cohort study with patients which were treated due to cystic lesions in the maxillofacial region between the years 2012-2018. Forty eight subjects were included and grouped regarding histopathologic diagnoses (radicular dentigerous and odontogenic keratocyst) and treatment methods (enucleation and marsupialization). The mean (range) of patients' age was 31.25 (18-66) years, and there were 32 male and 16 female individuals. The displacement of mandibular canals was verified on preoperative cone-beam computed tomographic images. The measurements of displacement and bone formation were performed on panoramic radiographs. In the statistical analysis of the data, descriptive statistics, parametric independent sample t-test, non-parametric Kruskal Wallis test, and one-way analysis of variance test were utilized.

Results: All the evaluated mandibular canals were replaced by a mean(SD) of 5.46(2.59) mm after the lesions eliminated, which was significant in the marsupialization group (p = 0.002). The bone formation was significantly higher in the enucleation group (p = 0.003). The multiple regression analyses revealed that the treatment methods significantly influenced the replacement of mandibular canal (p < 0.001) and the bone formation (p = 0.026).

Conclusion: In cases where there is an adequate distance between the lesion and the mandibular canal, the enucleation technique was found to be superior in terms of bone formation and the amount of bone height obtained.

Keywords: Cone-beam computed tomography; Displacement; Mandibular canal; Odontogenic cysts; Radiography, panoramic.