BACKGROUND: Orthognathic surgery is a multidisciplinary surgery in which the aesthetic results have become increasingly important, and consequently, also the predictability of the surgical outcomes. In this paper, we analyzed the volumetric distribution of the lower two-thirds of the face, in patients operated by orthognathic surgery and selected for their attractiveness. Our goal was to analyze the aesthetic volumetric distribution for gender and to propose our operating philosophy, that a normative distribution of facial volumes could be used like a new 3D aesthetic guide in orthognathic planning.
METHODS: A group of 46 orthognathic patients (26 females, 20 males) with the best postoperative aesthetic score was selected by a jury of plastic surgeons, orthodontists, and journalists. The mean soft tissue volumes of the malar, maxillary, mandibular, and chin regions were analyzed.
RESULTS: Overall, we measured a mean female facial volume distribution of 38.7%, 29%, 27.6%, and 4.7%, respectively, in the malar, maxillary, mandibular, and chin regions, while in males, it was 37%, 26%, 30%, and 6%, respectively.
CONCLUSIONS: In this paper, the expansion of facial volumes in orthognathic surgery is proposed as a key point for facial harmonization. Beauty could be scientifically interpreted as a balanced distribution of facial volumes, and the virtual study of this distribution can become an important part of the preoperative analysis, such as a \"volumetric\" 3D cephalometry, where the surgeon could use average values of aesthetic volumetric distribution as preoperative surgical references.

The purpose of this prospective study was to evaluate whether the surgical protocol involving marginal incision and Le Fort I osteotomy affects the periodontal outcome. Twenty-nine patients requiring surgical correction of maxillary dysgnathia were selected for this study. Periodontal conditions of maxillary anterior teeth were assessed prior to the surgery (T0), one month (T1), and 6 months (T2) after the surgical procedure. Interdental papillae loss, periodontal parameters and aesthetic outcomes in the anterior zone were assessed. Statistical analysis was performed with Friedman´s test and within ANOVA (p ≤ 0.05) followed by post-hoc tests. Papilla height decreased from T0 to T1 (p = 0.003), followed by an increase from T1 to T2 (p = 0.040). PPD (T0 = 1.72 ± 0.46; T2 = 2.13 ± 0.43) and CAL (T0 = 1.24 ± 0.55; T2 = 1.99 ± 0.70) increased after 6 months. There were statistically significant differences in aesthetic score among T0, T1 and T2. Periodontal changes after orthognathic surgery were within acceptable biological levels. Although a change in papillae height was reported after the surgery, initial values were recovered after 6 months. Surgical incision design might improve the outcome of Le-Fort I osteotomy. Anterior aesthetic zone may benefit from a marginal incision design, as it respects vascularization principle and may ensure a wound healing without complications.

Several systematic reviews have been published on the effects of mandibular surgery on condylar remodeling without reaching a consensus. The purpose of this systematic review of systematic reviews was to assess the impact of mandibular advancement or bimaxillary surgeries on condylar resorption. A literature search, using several electronic databases, was carried out by two reviewers independently. Article preselection was based on titles and abstracts, and final article selection based on full-text analysis of preselected studies. After final study selection, the quality of studies was assessed using the AMSTAR 2 tool. A decision algorithm was subsequently established to choose the best body of evidence. From an initial yield of 1\'848 articles, 23 systematic reviews were identified for further analysis, with ten studies being included in the final selection. Despite the generally low quality of the reviews, certain associations could be made: young patients, female patients, and those with a high mandibular plane angle are more prone to condylar resorption following mandibular advancement osteotomies, especially if anterior rotation of the mandible is performed during surgery. Patients undergoing bimaxillary surgery also appear to have a higher risk of developing condylar resorption. In conclusion, these results confirm the multi-factorial nature of condylar resorption, stressing the need for well-controlled prospective studies with long-term follow-up to clearly identify potential risk factors associated with orthognathic surgery.

Orthognathic surgery can cause substantial bleeding. Recent meta-analyses concluded that there is a statistically significant reduction in perioperative blood loss with the preventive use of tranexamic acid (TA). However, the mean reported difference in bleeding was moderate, and the clinical relevance of this blood-sparing effect remains debated. We therefore conducted a prospective, double-blind, randomized, placebo-controlled equivalence study of the effect of TA in patients undergoing Lefort I or bimaxillary osteotomies. Our main outcome measure was total blood loss on postoperative day 1. The equivalence margin was ± 250 ml for the difference in blood loss and its 95% confidence interval. One hundred and forty-seven patients were randomized, of which 122 underwent bimaxillary osteotomies. Blood loss in the treatment group was 682 ± 323 vs. 875 ± 492 ml. The mean difference in bleeding was -132 [-243; -21] ml as per-protocol, but -193 [-329; -57] ml in intention-to-treat: the limits of this confidence interval exceeded the margin of equivalence. Similar results were obtained when analysing only patients undergoing bimaxillary osteotomy. Haemoglobin decreased by 1.8 ± 1.2 g/dl with TA, vs. 2.6 ± 1.1 g/dl with placebo (p<0.001). Our study did not demonstrate equivalence between TA and placebo on perioperative blood loss in orthognathic surgery. TA may reduce blood loss but without evidence of clinical consequences.

The most common orthognathic surgery approach consists of three steps: presurgical orthodontic treatment, surgery, and postsurgical orthodontic treatment. Despite its advantages, this technique has some disadvantages, too, including a long treatment period, problems in mastication and articulation, temporary worsening of the patient\'s appearance, and psychological problems for the patient. The introduction of the surgery-first orthognathic approach has been an attempt to overcome these problems. In this article, we wish to provide a comprehensive overview on this approach. In this approach, which consists of surgery without orthodontic preparation and a short period of orthodontic treatment after it, the overall duration of treatment decreases and the patient\'s appearance improves. The skeletal anchorage, placed at the time of surgery, can be used to facilitate tooth movements after surgery. Despite the advantages of this technique, it is associated with some limitations; in particular, occlusion cannot have a guiding role during surgery. Therefore, correct diagnosis, prediction of the outcomes, and simulating correction with the model setup are of crucial importance. The surgeon\'s knowledge and expertise have a significant role in this respect.

Complications with bilateral sagittal split osteotomy (BSSO) can sometimes result from surgical inexperience. Our aim was to present a 3-dimensional printed mandibular model for BSSO training in a maxillofacial surgical education programme. A polymethacrylate mandibular model obtained from mandibular cone-beam computed tomographic (CT) images was designed and printed for use in training. Twenty-four residents were each asked to do a BSSO according to the Epker/Dal-Pont technique. The session was conducted as a simulation course with a final debriefing. A questionnaire before and after the test was filled in using a 10-point Likert scale to assess the participants\' knowledge. The mandibular model provided a realistic way of handling the trabecular bone after cortical osteotomy, as well as in the splitting phase. Significant increases in knowledge and surgical skills were noted for all steps of the BSSO, particularly regarding the use of the piezoelectric device for osteotomy, and for management of wisdom teeth in the splitting zone (3.00 ±2.16 to 6.95 ±2.06 and 2.73 ±1.91 to 5.75 ±2.63, respectively; p1=0.0002 and p2=0.0003). We think that this is a valuable printed mandibular model for the development of surgical skills for BSSO in maxillofacial surgical residents.