Currently, miniscrews or mini-implants, which are widely used as temporary anchorage devices for orthodontic treatment, are mainly made of grade 5 titanium alloy (Ti6Al4V). This allows for small-sized miniscrews less likely developing a fracture during insertion, reduces patient discomfort, and avoids root or periodontal ligament proximity when placed in the inter-radicular spaces. 1 Typically, the miniscrews are cylindrical and tapered and have a diameter of 1.0-2.3 mm and a length of 5.0-17.0 mm. They must be at least 1 mm in diameter and at least 3.8 mm in length within the alveolar bone, to ensure stability. 2 The failure rate of the miniscrew is 13.5%-14.0%, which is correlated with the cortical bone thickness. 3,4 The failure rate in the mandible is higher than that in the maxilla due to excessive insertion

Objectives This study aimed to assess the success rate and the amount of suture separation after the miniscrew-assisted rapid palatal expansion (MARPE) procedure in relation to the chronological age and sex of the patients. Materials and methods The periapical radiographs of 215 subjects (95 male; 120 female; range, 6–60 years) who had undergone MARPE treatment were retrospectively analyzed. The success of suture separation was determined and, in suture-separated subjects, the amount of suture separation was evaluated by suture separation ratio calculated from the periapical radiograph obtained after active expansion. Association tests were performed using linear-by-linear association, the Jonckheere-Terpstra test, Fisher’s exact test, and the Mann–Whitney U test, and linear regression models were also developed. Results The success rate of suture separation was 61.05% in male, 94.17% in female, and 79.53% in both sexes. There was a statistically significant association between older age and suture nonseparation in male (p < 0.001), but not in female (p = 0.221). In suture-separated subjects, there was a statistically significant trend toward a low amount of suture separation with older age subgroups in both sexes (p < 0.001); however, there was no statistically significant difference in the amount of suture separation between male and female in all age subgroups. Conclusions Older patients treated with MARPE, particularly in male, may have a reduced likelihood of both success in suture separation and sufficient basal bone expansion. Clinical relevance This study demonstrates that clinicians should consider that the success rate of MARPE and the amount of suture separation may depend on chronological age and sex.

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This retrospective observational study aimed to examine the correlation and correspondence between skeletal maturation indicators (SMI), cervical vertebral maturation indicators (CVMI), and radius-ulna-short bones (RUS) skeletal maturity scores in Korean adolescents, and to determine whether easily obtainable SMI or CVMI can replace the RUS skeletal maturity score. A total of 1017 participants were included with both hand-wrist radiograph and lateral cephalogram acquired concurrently. From the lateral cephalogram, CVMI was determined; through the hand-wrist radiograph, SMI was categorized, and the RUS skeletal maturity score was evaluated as well. Associations were examined using the Mann–Whitney U test, Spearman’s rank-order correlation analysis, and multiple correspondence analysis. There was no statistically significant difference in chronological age between males and females; however, the SMI, CVMI, and RUS skeletal maturity scores were significantly higher in females. The SMI, CVMI, and RUS skeletal maturity scores showed a statistically significant strong degree of both positive correlation and correspondence. However, a precisely corresponding RUS skeletal maturity score was difficult to obtain for a specific CVMI and SMI stage, implying the absence of a quantitative correlation. In conclusion, detailed evaluation should be conducted using the RUS skeletal maturity score, preferably in cases that require bone age determination or residual growth estimation.

Glossectomy combined with radiotherapy causes different levels of tongue function disorders and leads to severe malocclusion, with poor periodontal status in cancer survivors. Although affected patients require regular access to orthodontic care, special considerations are crucial for treatment planning. This case report describes the satisfactory orthodontic management for the correction of severe dental crowding in a 43-year-old female 6 years after treatment for tongue cancer with total glossectomy combined with radiotherapy, to envision the possibility of orthodontic care for oral cancer survivors. Extraction was performed to correct dental crowding and establish proper occlusion following alignment, after considering the possibility of osteoradionecrosis. Orthodontic mini-implants were used to provide skeletal anchorage required for closure of the extraction space and intrusion of the anterior teeth. The dental crowding was corrected, and Class I occlusal relationship was established after 36 months of treatment. The treatment outcome was sustained after 15 months of retention, and long-term follow-up was recommended.