Clinical course of masticatory function recovery following arthrocentesis in patients with unilateral mandibular condyle head fracture.

The aim of this study was to investigate the clinical course of masticatory function recovery following arthrocentesis. Patients with a unilateral condylar head fracture who underwent arthrocentesis for therapeutic reasons were evaluated and compared with patients with a unilateral condylar head fracture who did not undergo arthrocentesis. At 3 months after treatment, the occlusal contact area and maximum bite force in patients with a fracture treated with arthrocentesis were greater than in those who did not receive arthrocentesis at the same time points, although the differences were not significant. Moreover, at 1 and 3 months following arthrocentesis, mean (±SD) occlusal contact area (1 month: 1.99 ± 0.55 mm2, p = 0.01; 3 months: 2.90 ± 1.36 mm2, p = 0.03) and maximum bite force (1 month: 82.45 ± 15.04 N, p = 0.01; 3 months: 101.11 ± 14.53 N, p = 0.01) on the fractured side in patients who underwent that treatment were significantly reduced when compared with those on the non-fractured side. The authors conclude that if the priority is to avoid open reduction and internal fixation, then the arthrocentesis approach might be a less invasive alternative, albeit with the price of a prolonged healing interval.

Mandible fractures and dental injuries related to road traffic accidents over a 12-year period-Retrospective multicentre study.

BACKGROUND/AIM: Road traffic accidents (RTAs) are a common cause of maxillofacial injuries. The aim of this retrospective multicentre study was to investigate the characteristics of maxillofacial fractures and dental injuries that occurred in RTAs in Miyagi, Japan. MATERIALS AND METHODS: The records of 404 patients with maxillofacial injuries treated at the Oral and Maxillofacial Surgery Departments of four different institutions over a period of 12 years were analysed. Ninety-nine of these patients had suffered these injuries in an RTA. RTA-related cases were divided according to age, gender, presentation month, presentation day of the week, transportation mode, time of accident, fracture sites and fracture mechanism. RESULTS: There were 72 males and 27 females who suffered injuries as the result of an RTA, for a male-to-female ratio of 2.7:1.0, with a mean age of 35.3 years (range, 1-86 years old). Most of the accidents occurred in June and on a Wednesday, and most of the affected patients were riding a bicycle at the time. The number of patients with maxillofacial injuries related to bicycle riding showed an increasing trend in recent years. Mandible fractures were the most prevalent, followed by dental injuries and maxilla fractures. In cases with a single fracture of the mandible, the symphysis was the most frequent site, while in those with multiple fractures, the association of symphysis and bi-lateral condyle fractures was the greatest. For bicycle-related accidents, a single fracture in the mandible occurred more often than multiple fractures. CONCLUSIONS: The number of RTA-related injuries while bicycle riding showed an increasing trend with mandible fractures commonly seen in those cases. Efforts to reduce maxillofacial injuries related to bicycle accidents are needed.

Mandibular fractures and dental injuries sustained during baseball and softball over 14 years in a Japanese population: A retrospective multicentre study.

BACKGROUND/AIM: Active participation in sports is a risk factor for maxillofacial fractures. The aim of this retrospective multicentre study was to survey and evaluate the characteristics of mandibular fractures, and dental injuries that occurred during the practice of baseball and softball in Sendai, Japan. MATERIAL AND METHODS: The records of 454 patients with maxillofacial fractures from three departments of Oral and Maxillofacial Surgery across a period 14 years were analysed. Fifty-one patients with 56 mandible fractures and dental injuries that occurred playing baseball or softball were included in this multicenter retrospective study. Patients were divided according to age, gender, sites of fractures, mechanism of fractures and treatment methods. RESULTS: There were 42 males and nine females, with a male-to-female ratio of 4.7:1.0. The mean age was 19.9 years old (range: 13-47 years old). As for the site, body of the mandible fractures prevailed, followed by the condyle, symphysis and angle. Fractures were mostly caused by the impact of a ball (42; 82.4%), followed by collisions with another player (5; 9.8%) and direct strike of a bat (4; 7.8%). All patients with mandibular fractures were treated with open reduction and internal fixation, except for six patients with condylar head fractures who were managed conservatively. CONCLUSIONS: The impact of a thrown ball against the batter's mandible can cause a condylar fracture when playing baseball and softball.

Fall-related mandible fractures in a Japanese population: A retrospective study.

BACKGROUND/AIM: Maxillofacial trauma is frequent and represents a heavy burden for patients and society. The aim of this study was to investigate the characteristics and management of mandibular fractures caused by falls. MATERIAL AND METHODS: One hundred thirty-nine patients with 185 mandible fractures caused by falls were included in this retrospective study. The patients were grouped according to age, gender, fitness level (as classified by the American Society of Anesthesiology physical status classification), the month of the accident, sites of fractures and treatment methods. RESULTS: Most adult and fit patients were treated with open reduction and internal fixation, except for intracapsular condyle fractures. Conservative management was chosen for paediatric patients and in all cases deemed at high risk for lengthy procedures under general anaesthesia (physical status III according to the American Society of Anesthesiology). Young patients were mainly males, whereas geriatric patients were mainly females. In cases of single-site fracture, condylar fractures were the most prevalent. In cases with multiple sites, the association of condyle and symphysis fractures was the most frequent. CONCLUSIONS: The results show an increasing trend in geriatric condyle fractures, especially in females. The epidemiology of fall-related mandibular fractures is subject to the influence of seasonal, historical, cultural and demographic factors.

Experimental Comparison of the Performance of Cutting Bone and Soft Tissue between Piezosurgery and Conventional Rotary Instruments.

Piezosurgery is an innovative technique widely used for osteotomies in the field of oral and maxillofacial surgery. The surgical technique has been clinically supposed to cut mineralized bone selectively with reducing the risk of damage to adjacent soft tissues. However, none of the previous literature has reported any evidence of scientific experiments to examine performance of the piezoelectric device, i.e. the time required for cutting bone and the effect on soft tissues under the standardized conditions. This study was designed to test the hypothesis that cutting time of the piezoelectric device is longer than that of rotary instruments while the cut surface of bone is smoother and soft tissues are less damaged with piezosurgery under the standardized experimental system. We measured the time for cutting bone and soft tissues of rats with the piezoelectric device and rotary instruments. Damage to soft tissues was examined histologically, and the cut surface of bone was investigated using scanning electron microscopy. Our study demonstrated experimentally that piezosurgery provides a smooth cut bony surface with no damage to soft tissues and takes longer time to cut bone than conventional drillings. We propose that piezosurgery is beneficial for medical safety and usability.

Do Mandibular Third Molars Play a Role in Fractures of the Mandibular Angle and Condyle?

INTRODUCTION: The relationship between impacted mandibular third molars with angle and condylar fractures is subject of many publications, yet their conclusions differ widely, hence the authors wanted to investigate this topic in their patients. METHODS: The authors designed a retrospective study including 241 patients who presented with angle and/or mandibular condyle fractures over a 13-year period at the authors' institution. The study variable was the presence/absence of third molars. The authors used the Pell and Gregory system to classify their position, whereas the angulation was classified using Archer classification. The outcome variables were the presence of angle and condylar fractures. Other study variables included fracture etiology. RESULTS: Assaults were the most frequent cause of angle fractures (62.7%), whereas falls were mostly responsible for condylar fractures (79.6%). Angle fractures were mostly isolated (66.3%), whereas condylar fractures were mostly associated with other fractures (62.6%). The majority of the angle fractures occurred in patients with third molars (63.6%), on the contrary the majority of the condylar fractures occurred in patients without mandibular third molars (78.3%). Angle fractures were mostly associated with fully erupted or superficially impacted third molars (90,9%). Finally in the presence of mesioangulated third molars, condylar fractures did not happen in 83.8% of patients. CONCLUSIONS: According to the authors' findings, fully erupted or superficially impacted mandibular third molars are a risk factor for angle fractures but at the same time a protective factor for the condyle. On the contrary, the absence of mandibular third molars "strengthens" the angle and represents a risk factor for condylar fractures.