Background: There is relatively little appreciation of the changes in maxillary-mandibular relationships occurring during adolescence among subjects with normal and increased overjet. The aim of this study was to assess differences in changes in maxillo-mandibular relationships during the adolescent growth period based on the presence of a normal (< 4 mm) or increased (> 4 mm) overjet in childhood. Our hypothesis was that there is no difference in the change of the A point, nasion, B point (ANB) angle during growth between these two overjet groups. Lateral cephalograms were obtained from 65 subjects taken from the American Association of Orthodontists Foundation (AAOF) Craniofacial Growth Legacy Collections Project. Cephalograms were obtained at ages 7-10 (T0) and 14-17 (T1) with allocation into two groups based on baseline overjet (> 4 mm: group 1, 2-4 mm: group 2). Random effects linear regression was used to account for multiple within-patient measurements with dependent variables including anteroposterior skeletal pattern (based on sella, nasion, A point (SNA); sella, nasion, B point (SNB); and ANB angles). Results: We included a similar number of males (n = 34; 52.3%) and females (n = 31; 47.7%). The mean ANB was higher at baseline in group 1 (5.42, SD 2.16°) than in group 2 (3.08, SD 1.91°). The hypothesis was rejected as the ANB angle reduced by 1.92°more in the larger overjet group with the association being statistically significant after accounting for age and gender (P < 0.001; 95% CI 1.06 to 2.77). No significant gender-related effect (P = 0.624; 95% CI − 0.637 to 1.07) was observed overall. However, there was no significant increase in SNA angle in the > 4 mm overjet group compared to the 2-4 mm group (0.857°, P = 0.271; 95% CI − 0.669 to 2.383). The SNB angle increased by 1.15°m ore in the higher overjet group but there was only weak evidence of an association (P = 0.086; 95% CI − 2.464 to 0.164). Conclusions: A slight straightening of the facial profile was observed in both groups with a statistically significant greater reduction in ANB arising in the group with larger baseline overjet. This translated into a marginal reduction in the overjet in this group.

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Introduction The reported incidence of titanium miniplate removal after orthognathic surgery varies widely, making delivery of risk information to patients problematic. This variation relates to potential biases introduced during the study design, for example, with the pooling of different patient types, creating heterogeneous study samples. This study reduces sampling bias by limiting the cohort to only consecutive orthognathic cases. The primary aim of the study was to identify the incidence of miniplate removal following orthognathic surgery. The secondary aim was to assess the indications and any risk factors for miniplate removal. Methods Data from the clinical records of 907 orthognathic surgery cases treated within a centralised oral and maxillofacial hospital service over a 10-year period were collected by two operators and analysed. Every identified case qualified for inclusion. Patient demographics (age, sex, medical comorbidity, smoking), operations (type of surgery, duration, third molar removal, complications) and the indication, timing and site of miniplate removal were analysed. Results Only 19 patients required postoperative miniplate removal, with the most common indication being infection (63%). There was no significant difference in any of the factors assessed except that significantly more miniplates were removed from female patients (68%) (p<0.001) and from mandibular sites (84.2%) (p=0.003). Conclusions The incidence of miniplate removal for this sample was 2.1%. Female sex and miniplate location in the mandible were the only statistically significant risk factors for miniplate removal.

This is the third article in a three-part series considering skeletal discrepancies in the vertical and transverse dimensions. Significant discrepancies in the transverse dimension are relatively rare but present challenges for the orthodontist, in terms of treatment planning, management and relapse. CPD/Clinical Relevance: This article aims to increase awareness of the assessment, aetiology and management of patients presenting with facial asymmetry.