Evaluation of the Relationship between Mandibular Impacted Wisdom Teeth and Mandibular Canal in Preoperative Panoramic and Postoperative Complication


1 Assistant Professor, Department of Prosthodontics, School of Dentistry, Mazandaran University of Medical Sciences, Sari, Iran

2 Assistant Professor, Department of Oral and Maxillofacial Surgery, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran

3 Orthodontist, Iran

4 Assistant Professor, Health Sciences Research Center, Mazandaran University of Medical Sciences, Sari, Iran


Background & Aims: Before the surgery of lower impacted third molars, it is essential to evaluate the relationship of the roots to mandibular canal using radiographies in order to avoid postoperative complications. The purpose of this study was to evaluate the reliability of panoramic radiographs in assessing this relationship. Methods: This was a prospective study. The study population consisted of 103 candidates for impacted lower third molar surgery. Before surgery, panoramic radiographs were taken and the relationship between mandibular canal and the root of impacted lower third molar was determined. Subsequently, a comparison was made between radiographic findings and postoperative complications 1 week after surgery (gold standard) and the compatibility between them was determined. Results: Based on panoramic findings, 36 (35%) patients had mandibular canal involvement. Moreover, complications after surgery were observed in 12 (11.7%) patients. Fisher's exact test showed that postoperative complications had a significant relationship with radiographic findings. In 70.9% of the patients, there was compatibility between radiographic findings and the results of the gold standard. Conclusion: Considering the limitations of this technique, this method is proposed as a primary technique for evaluating the involvement of the third molar and mandibular canal, and if the involvement is suspected, using advanced techniques such as computed tomography scan (CT-scan) is indicated.


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