A retrospective analysis of redo orthognathic surgery: Underlying causes, strategy, and outcome

Frontal facial analysis of female celebrity attractiveness standards through artificial intelligence

The contemporary significance of celebrities' facial aesthetics underscores their heightened importance in shaping attractiveness standards. This retrospective study aimed to investigate the impact of patterns on aesthetic canons in the profile views of female celebrities, using artificial intelligence. The study sought to compare different races and propose standards for attractive faces. In this retrospective cohort study, a Python-based algorithm was used to analyze frontal patterns and evaluate their influence on aesthetic norms in publicly accessible images of female global celebrities. Ten ideal angular or proportional measures were gathered from the literature, and were trained to serve as a benchmark for the analysis of facial attractiveness. Demographic characteristics were described statistically. A one-way ANOVA test was employed to assess data distribution. Differences in means between groups were evaluated using nonparametric independent-sample tests, with statistical significance set at < 0.05. The study involved facial analyses for 115 female celebrities. It revealed variations in facial features among races. The mean golden ratio differed, with African and Asian individuals showing lower ratios. Symmetry varied, with Latin and Caucasian faces considered the most symmetrical. The zygomatic-to-mandibular width ratio was similar across races, with a ratio close to 80% being associated with more attractive faces. Differences in nose-to-mouth ratio, lips, alar base width, and chin angle were noted among race groups. The study concluded that, regardless of race, an attractive female face is characterized by specific ratios and angles. Facial symmetry, though desirable, is not strictly necessary. Irrespective of race background, an appealing female face is characterized by a zygomatic-to-mandibular width ratio nearing 80%, a mid-facial third that is slightly larger than the lower third, and a distinctive chin angle of approximately 138°, contributing to a trapezoidal facial shape. The findings contribute valuable insights into attractiveness standards and the impact of frontal patterns on aesthetic canons in female celebrities.

Comparison between one-jaw and two-jaw designs in virtual surgery planning for patients with class III malocclusion

Orthognathic surgery is highly effective for treating maxillomandibular discrepancies in patients with class III malocclusion. However, whether one- or two-jaw surgery should be selected remains controversial. Our study aimed to evaluate quantitative differences between one-jaw and two-jaw surgical designs. In total, 100 consecutive patients with skeletal class III malocclusion who underwent orthognathic surgery with preoperative three-dimensional simulation between August 2016 and November 2021 were recruited. Based on the same final occlusal setup, a two-jaw surgery design and two types of one-jaw design were created. In total, 400 image sets, including preoperative images and three types of surgical simulation, were measured and compared. The one-jaw mandibular setback design led to improvement in most cephalometric measurements and facial symmetry. Although the one-jaw maxillary advancement design improved the ANB angle and facial convexity, it induced maxillary protrusion and reduced facial symmetry. Compared with the other designs, the two-jaw design provided significantly closer cephalometric measurements to the normative values, better symmetry, and less occlusal cant. Overall, the two-jaw design provided a quantitatively better facial appearance in terms of symmetry, proportion, and profile. Although an optimal surgical design necessitates thorough preoperative evaluation and a shared decision-making process, two-jaw surgery can be considered for improving overall facial esthetics and harmony.

Skeletal stability after mandible bilateral sagittal split osteotomy - comparison of patient-specific implant and mini-plate fixation: A retrospective study

The aim of the study was to compare the stability of the virtual surgical planning (VSP) and computer-aided design accompanied by patient-specific implants (PSIs) and conventional mini-plates in mandible advancement with bilateral sagittal split osteotomy (BSSO). This retrospective study evaluates the clinical and cephalometric records of 53 patients (12 male, 41 female) treated with BSSO in Helsinki University Hospital. Subjects were divided into two groups: VSP-PSI (21 patients: 4 male and 17 female; mean age 38 years, range 25-53 years); and conventional wafer-based repositioning with mini-plate fixation (32 patients: 8 male and 24 female; mean age 39 years, range 21-56 years). The effect of the amount and direction of the advancement on the stability was also analysed individually. The standardized lateral cephalometric radiographs in three time points were analysed to compare the groups. After surgery (T2), there were no differences between groups in cephalometric variables. During follow-up (T2-T3), the cephalometric variables in both Groups A and B were stable, so there was no difference in stability between the VSP-PSI and the conventional mini-plate groups. During follow-up, the mandibles rotated clockwise or counterclockwise, relapsed towards their original direction, and the changes were statistically significant (jaw relationship; p = 0.018, soft tissue profile; p = 0.025); when the advancement of mandible was >6 mm, the increase in gonial angle compared to mandibles advanced ≤6 mm was statistically significant (p = 0.03). VSP-PSI and conventional mini-plate fixation can be considered equally stable. Large advancements with counterclockwise rotation regardless of fixation method are more susceptible to relapse. VSP-PSI alone cannot solve the relapse-related concerns in mandible osteotomy.