OBJECTIVES: To explore risk factors for contact between the incisive canal (IC) and upper central incisors (U1) and to evaluate the relationship between contact and root resorption using cone-beam computer tomography (CBCT). MATERIALS AND METHODS: This retrospective study used CBCT data of 33 patients treated by a senior orthodontist. Anterior teeth were retracted with mini-implants, and CBCT scans were taken before and after retraction. IC height and width, U1 lingual movement, and U1-IC distance and root length decrease were compared between contact and noncontact groups. RESULTS: Sixteen U1 roots in 11 patients touched the IC. The contact group had lower positioned ICs (2.86 ± 1.10 mm) than the noncontact group (4.07 ± 1.72 mm). The middle of the U1 roots showed more lingual movement to ICs in the contact group (2.30 ± 1.20 mm) than in the noncontact group (1.07 ± 1.16 mm). Right central incisors were closer to the IC than were the left. Root length decreased significantly more in the contact group (2.63 ± 0.93 mm) than in the noncontact group (1.14 ± 0.83 mm). CONCLUSIONS: There is a risk for the U1 root to contact the IC during anterior retraction when the IC is lower positioned. This contact might cause external apical root resorption.
OBJECTIVES: To explore risk factors for contact between the incisive canal (IC) and upper central incisors (U1) and to evaluate the relationship between contact and root resorption using cone-beam computer tomography (CBCT). MATERIALS AND METHODS: This retrospective study used CBCT data of 33 patients treated by a senior orthodontist. Anterior teeth were retracted with mini-implants, and CBCT scans were taken before and after retraction. IC height and width, U1 lingual movement, and U1-IC distance and root length decrease were compared between contact and noncontact groups. RESULTS: Sixteen U1 roots in 11 patients touched the IC. The contact group had lower positioned ICs (2.86 ± 1.10 mm) than the noncontact group (4.07 ± 1.72 mm). The middle of the U1 roots showed more lingual movement to ICs in the contact group (2.30 ± 1.20 mm) than in the noncontact group (1.07 ± 1.16 mm). Right central incisors were closer to the IC than were the left. Root length decreased significantly more in the contact group (2.63 ± 0.93 mm) than in the noncontact group (1.14 ± 0.83 mm). CONCLUSIONS: There is a risk for the U1 root to contact the IC during anterior retraction when the IC is lower positioned. This contact might cause external apical root resorption.
Entities:
Keywords:
CBCT; Incisive canal; Root resorption; Upper central incisors
Authors: Tolga F Tözüm; Güliz N Güncü; Yağmur D Yıldırım; Hasan Güney Yılmaz; Pablo Galindo-Moreno; Miguel Velasco-Torres; Khalid Al-Hezaimi; Raed Al-Sadhan; Erdem Karabulut; Hom-Lay Wang Journal: J Periodontol Date: 2011-09-12 Impact factor: 6.993
Authors: Will A Andrews; Wakas S Abdulrazzaq; Jeffrey E Hunt; Lucas M Mendes; Linda A Hallman Journal: Angle Orthod Date: 2022-01-01 Impact factor: 2.079