Condylar resorption following mandibular advancement or bimaxillary osteotomies: A systematic review of systematic reviews.

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.

Large overjet as a risk factor of traumatic dental injuries: a prospective longitudinal study.

PURPOSE: The aim of this longitudinal prospective study was to evaluate if schoolchildren with large overjet experience a greater risk of traumatic dental injuries (TDI) compared to children with normal or small overjet. METHODS: A sample of children aged 6­13 years was prospectively evaluated after 1 year: from the initial sample, data concerning trauma cases of 1413 children were collected to determine the number and types of injuries, the influence of overjet on the risk of TDI, and the relationships between trauma, age, and gender. RESULTS: The observed prevalence of trauma was higher for boys, with the largest frequency between the ages of 8 to 12 years: 67.9% of all injuries were hard tissue injuries and 32.1% subluxation and luxation injuries. Children with an overjet of 6 mm or more showed a statistically increased risk of getting trauma [RR = 3.37 with CI (1.81; 6.27)]. CONCLUSION: In this prospective study, overjet stood out among variables as the most significant risk factor of TDI: an increased overjet of 6 mm or more had a major impact on the risk of trauma, which would speak in favor of early orthodontic correction of an increased overjet to reduce the prevalence of dental trauma.

Prevalence of traumatic injuries to permanent dentition and its association with overjet in a Swiss child population.

OBJECTIVE: Dental trauma is a very common issue in dentistry and its occurrence has been related to many factors. The aim of this study was to evaluate the prevalence of traumatic dental injuries in the permanent dentition among Swiss children and its association with overjet. MATERIAL AND METHODS: A sample of 1900 children aged 6-13 years was prospectively evaluated to determine the number and types of injuries, the influence of overjet on the risk of suffering trauma and the relationships between trauma, age, gender and life conditions. RESULTS: The observed prevalence of trauma was higher for boys, with a slight risk increase with age and a peak frequency at the age of 10 years. Most of the injuries (91.2%) involved the upper front teeth; 87.2% of all injuries were hard tissue injuries (enamel or dentin fractures), and 12.8% only subluxation and luxation injuries. Children with an overjet of 6 mm or more had a four times higher risk of suffering trauma, compared with those with less overjet. CONCLUSION: This cross-sectional study confirmed most of the results from earlier studies dealing with epidemiological factors of dental injuries to the permanent dentition. Of all the variables analysed, overjet stood out as the most significant risk factor: an increased overjet of 6 mm or more had a major impact on the risk of trauma, which would speak in favour of early orthodontic correction of an increased overjet to reduce the prevalence of dental trauma.