Biomechanical analysis of fractures in the mandibular neck (collum mandibulae)

After treatment of fractures in the neck of the mandible by means of immobilization of the dentition, often more or less severe manifestations of malocclusion remain. It was hypothesized that this is caused by an altered articulation in the jaw joint on the affected side. Furthermore, it was hypothesized that an anteriorly displaced condyle, as observed frequently as a side effect of the treatment, is caused by pull of the lateral pterygoid muscle, despite maxillomandibular fixation. Intervention experiments were performed in silico to test these hypotheses. With a biomechanical model of the human masticatory system alterations were applied mimicking a fractured mandibular neck and configurations that had been observed after healing. It was predicted that the altered articulation in the jaw joint caused asymmetrical jaw movements despite symmetrical muscle activation. The jaw was predicted to close with an open bite similar to clinical observations. The predicted laterodeviations, however, were not in accordance with clinical observations. Despite maxillo-mandibular fixation the lateral pterygoid muscle was able to pull the mandibular condyle out of its fossa in anterior direction. Consequently, despite some methodological limitations, in general the predictions corroborated the hypotheses

Consensus or controversy? The classification and treatment decision-making by 491 maxillofacial surgeons from around the world in three cases of a unilateral mandibular condyle fracture

Purpose Many studies are available in the literature on both classification and treatment of unilateral mandibular condyle fractures. To date however, controversy regarding the best treatment for unilateral mandibular condyle fractures remains. Material and methods In this study, an attempt was made to quantify the level of agreement between a sample of maxillofacial surgeons worldwide, on the classification and treatment decisions in three different unilateral mandibular condyle fracture cases. Results In total, 491 of 3044 participants responded. In all three mandibular condyle fracture cases, a fairly high level of disagreement was found. Only in the case of a subcondylar fracture, assuming dysocclusion was present, more than 81% of surgeons agreed that the best treatment would be open reduction and internal fixation. Conclusions Based on the study results, there is considerable variation among surgeons worldwide with regard to treatment of unilateral mandibular condyle fracture. 3D imaging in higher fractures tends to lead to more invasive treatment decisions

Aetiology of maxillofacial fractures: a review of published studies during the last 30 years

The epidemiology of facial trauma may vary widely across countries (and even within the same country), and is dependent on several cultural and socioeconomic factors. We know of few reviews of published reports that have considered the sex distribution and aetiology of maxillofacial trauma throughout the world. The aim of this review was to discuss these aspects as they have been presented in papers published during the last 30 years. We made a systematic review of papers about the epidemiology of maxillofacial trauma that were published between January 1980 and December 2013 and identified 69 studies from Africa (n=9), North America and Brazil (n=6), Asia (n=36), Europe (n=16), and Oceania (n=2). In all the studies men outnumbered women, the ratio usually being more than 2:1. In American, African, and Asian studies road traffic crashes were the predominant cause. In European studies the aetiology varied, with assaults and road traffic crashes being the most important factors. In Oceania assaults were the most important. A comparison of the incidence of maxillofacial trauma of different countries together with a knowledge of different laws (seat belts for drivers, helmets for motocyclists, speed limits, and protection worn during sports and at work) is crucial to allow for improvement in several countries. To our knowledge this paper is the first attempt to study and compare the aetiologies of maxillofacial trauma

Quality of life after open versus closed treatment for mandibular condyle fractures: a review of literature

Introduction Many studies have compared treatment outcomes after open reduction and internal fixation (ORIF) and closed reduction (CR) of mandibular condylar fractures. Despite this the optimal treatment for these fractures remains a controversy. The purpose of this review is to compare the influence of objective and subjective treatment outcomes after open versus closed treatment of mandibular condyle fractures on quality of life, based on the current literature. Methods A MedLine and Embase search was performed to find relevant titles on treatment outcomes after open versus closed reduction of mandibular condylar fractures. Results Thirty-six studies were found. Twenty-eight retrospective studies, in addition to eight prospective studies were assessed. Nine treatment outcome variables were evaluated from the studies. Three studies reported on subjective discomfort. Although many studies investigated (objective) measurements (e.g. range of motion, masticatory function), no studies evaluated quality of life outcomes. In conclusion, prospective, patient-centred research is needed, in order to provide a guideline in decision making in the treatment of mandibular condylar fractures, based on subjective patient satisfaction