Anna Westerlund1, Mats Sjöström2, Lena Björnström3, Maria Ransjö4. 1. Associate Professor, Department of Orthodontics, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden. Electronic address: anna.westerlund@odontologi.gu.se. 2. Senior Lecturer, Section for Oral and Maxillofacial Surgery, Department of Odontology, Umeå University, Umeå, Sweden. 3. Senior Orthodontic Consultant, Regional Center for Cleft and Lip Palate, Umeå University Hospital, Umeå, Sweden. 4. Professor, Department of Orthodontics, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; former Senior Orthodontic Consultant, Regional Center for Cleft and Lip Palate, Umeå University Hospital, Umeå, Sweden.
Abstract
PURPOSE: It is important to predict and prevent the impaction of canines. The aim of this study was to estimate the prevalence of impacted canines in patients with unilateral cleft lip and palate (UCLP) and to identify factors associated with impaction. MATERIALS AND METHODS: This retrospective cohort study included patients with nonsyndromic UCLP. The predictors were pre-eruptive inclination angle, deviation in tooth number (agenesis or supernumerary lateral incisors), and reoperation of bone transplant. The outcome variable was impacted and surgically exposed canines. RESULTS: The prevalence of impacted and surgically exposed canines in the 68 consecutive patients with UCLP was 20.6%. The pre-eruptive inclination angle was significantly larger (34.4°) for the impacted canines on the cleft side compared with the spontaneously erupted canines on the cleft and non-cleft sides (25.5° vs 15.4; P < .05). Reoperation of the bone transplant significantly increased canine impaction (50%; P < .05). CONCLUSION: The eruption of maxillary canines needs to be supervised carefully in patients with UCLP, because the prevalence of impaction is 10 times higher compared with the general population. Factors associated with canine impaction are a pre-eruptive inclination larger than 30° and reoperation of the bone transplant.
PURPOSE: It is important to predict and prevent the impaction of canines. The aim of this study was to estimate the prevalence of impacted canines in patients with unilateral cleft lip and palate (UCLP) and to identify factors associated with impaction. MATERIALS AND METHODS: This retrospective cohort study included patients with nonsyndromic UCLP. The predictors were pre-eruptive inclination angle, deviation in tooth number (agenesis or supernumerary lateral incisors), and reoperation of bone transplant. The outcome variable was impacted and surgically exposed canines. RESULTS: The prevalence of impacted and surgically exposed canines in the 68 consecutive patients with UCLP was 20.6%. The pre-eruptive inclination angle was significantly larger (34.4°) for the impacted canines on the cleft side compared with the spontaneously erupted canines on the cleft and non-cleft sides (25.5° vs 15.4; P < .05). Reoperation of the bone transplant significantly increased canine impaction (50%; P < .05). CONCLUSION: The eruption of maxillary canines needs to be supervised carefully in patients with UCLP, because the prevalence of impaction is 10 times higher compared with the general population. Factors associated with canine impaction are a pre-eruptive inclination larger than 30° and reoperation of the bone transplant.