Age-related changes in the effect of rapid maxillary expansion on the position of labially impacted maxillary canines: A case-control study

• Published in: American journal of orthodontics and dentofacial orthopedics 2021-03, Vol.159 (3), p.305-311
• Main Authors: Harada-Karashima, Momoko, Ishihara, Yoshihito, Kamioka, Hiroshi, Kanomi, Ryuzo
• Format: Article
• Language: English
• Subjects: Case-Control Studies; Child; Cuspid - diagnostic imaging; Humans; Maxilla - diagnostic imaging; Palatal Expansion Technique; Tooth, Impacted - diagnostic imaging; Tooth, Impacted - therapy
• ISSN: 0889-5406; 1097-6752
• DOI: 10.1016/j.ajodo.2019.10.026

The early diagnosis and interception of potential maxillary canine impaction is the most desirable approach for correcting their path of eruption. However, there is still a lack of evidence regarding the effect of rapid maxillary expansion (RME) on labially impacted canines. This study aimed to investigate the age-related effect of RME on labially impacted maxillary canines in order to reduce the risk of their impaction in the mixed dentition and to examine the proper timing of interceptive treatment. All patients aged 7-10 years were treated with an RME appliance using the same protocol. The distance to the occlusal plane, axis to the midline, and distribution in different sectors—depending on the patients' age—were evaluated for maxillary canines before and after treatment on panoramic radiographs in order to detect changes in the position of the impacted canines. These geometric measurements in the impacted canines were also validated by observing the nontreated canines at each age. Significant differences existed between the impacted canines and the erupted canines in all 3 categories in all age groups. RME treatment modulated the position of the impacted canines in all age groups. Interestingly, a statistically significant difference before and after RME in all categories was detected in patients aged