Study of the incisive mandibular canal by means of cone beam computed tomography

Author(s)

Thaís Sumie Nozu Imada

• Document type: Master's Dissertation
• Press: Bauru.
• Institution: Universidade de São Paulo (USP). Faculdade de Odontologia de Bauru (FOB/SDB)
• Defense date: 2011-05-23

Examining board members

Izabel Regina Fischer Rubira de Bullen; Mariela Siqueira Gião Dezotti; Renato Yassutaka Faria Yaedú

• Advisor: Izabel Regina Fischer Rubira de Bullen

Abstract

The mandibular interforaminal region is usually considered a safe area. It heldsvital anatomical structures and common surgical interventions such as placement of dental implants and procedures of orthognathic surgery are performed in this area. The Mandibular Incisive Canal (MIC) is a significant anatomical feature located in this region, often overlooked and that can cause surgical complications.The radiographic planning is one of the most important aspects of presurgical assessment to avoid injuries to these important structures, however, conventional radiographs (intraoral and panoramic) used nowadays remains limited when it comes to interpretation of the incisive canal. Cone beam computed tomography (CBCT) offers tridimensional image of the incisive canal allowing a comprehensive study of its course and morphology Objective: To establish the rate of visibility, length, location and course of CI by means of cone beam computed tomography and on digital panoramic. Material and Methods: The study group consisted of 100 CBCT random scans obtained from the Department of Stomatology of Bauru Dental Schools files. The images were taken using i-Cat CBCT device, applying a standardized exposure protocol and analyzed by i-Cat Vision software. The visibility of IC was studied at panoramic, cross-section and coronal scans. Its length and location were also analyzed from mentual foramen to the mandible midline. Subsequently, a comparison was made with the rates of visibility at the digital panoramic radiography from the same patients. Results: The visualization of the incisive canal at digital panoramic averaged 20.5% while the reconstruction of the CBCT panoramic visibility was around 45%. The McNemar test showed statistical difference, indicating the superiority of CBCT over panoramic radiograph for CI visualization. In crossectional reformatation, the average between the sides in the postforament area was 42%, in the region of canines was 28.5%, in the region of the lateral incisors was 11.5% and in the region of central incisorswas 4%. In coronal reconstruction, these values were 68%, 44%, 22% and 9% in the different regions. The average length of IC visible from the mental foramen was 9.18 mm in the different panoramic reformations. The average distance of crossectional reformatations of IC to the mandibular base was 10.10, IC to the tooth apex was 8.34mm, the IC to the alveolar ridge was 12.87mm, IC to buccal plate was 4.04mm and CI to the lingual plate was 5.21mm. There were no statistical differences in relation to the side, age and gender of the patient.ICs route was downward from the vestibular to the lingual plate. Conclusion: The superiority in the detection and high appearance rates of IC with CBCT showed the great importance of preoperative examination using CBCT for surgical procedures in the anterior mandible. (AU)

• FAPESP's process: 09/03758-6 - Study of the incisive canal by means of cone beam computadorized tomography (CBCT)
• Grantee: Thaís Sumie Nozu Imada
• Support Opportunities: Scholarships in Brazil - Master