Identification of mandibular fracture epidemiology in Canada: Enhancing injury prevention and patient evaluation.

BACKGROUND: Mandibular fractures can lead to significant functional and aesthetic sequelae if treated improperly. They may act as an indicator of concomitant trauma and are very demanding on the public health care system. Thus, knowledge of mandibular fracture epidemiology is critical to effective prevention, as well the establishment of accurate trauma evaluation protocols. OBJECTIVES: To identify the epidemiology of mandibular fractures treated at a level 1 Canadian trauma centre, clarify the pathogenesis of these epidemiological patterns and suggest potential targets for preventive efforts. METHODS: A retrospective review of all mandibular fracture patients presenting to the Montreal General Hospital between 1998 and 2003 was performed. Medical records and digitized radiographic imaging were used to collect patient demographics and injury data. RESULTS: The chart review identified 181 patients with 307 mandibular fractures. Fifty-two per cent of the fractures occurred in individuals 21 to 40 years of age, 78% of patients were male, and there was wide ethnic diversity. Sixty percent of patients had multiple mandibular fractures; 29% were symphyseal/parasymphyseal fractures, 25% were condylar fractures and 23% were angle fractures. Assault was the most common mechanism of injury, with 29% of fractures involving alcohol or illegal drug use. Thirty percent of patients had an associated facial fracture, and more than one-third had another major injury. CONCLUSIONS: The present epidemiological review reveals several potential prevention targets as well as significant trends. Further research into the impact of these preventive measures could more objectively identify their impact on mandibular trauma.

A multi-centre study of Osseotite implants supporting mandibular restorations: a 3-year report.

This multi-centre study evaluated the performance of the Osseotite implant in the mandibular arch. Osseotite implants (n = 688) were placed in 172 patients; 43.5% were placed in the anterior mandible and 66.5% in the posterior mandible. Fifteen per cent of the implants were placed in soft bone, 56.9% in normal bone and 28.1% in dense bone. During placement, 49.9% of the implants were identified as having a tight fit, 48.6% a firm fit and 1.5% a loose fit. About one-third of the implants (32.4%) were short (10 mm in length or less). After 36 months, only 5 implants had been lost, for a cumulative survival rate of 99.3%. The 3-year results of this study indicate a high degree of predictability with placement of Osseotite implants in the mandibular arch.

Compensatory renal growth post fetal nephrectomy in the rabbit.

Compensatory renal growth post-nephrectomy is well documented both clinically and experimentally. However, little is known about the capacity for compensatory growth in utero. We performed unilateral nephrectomy in fetal rabbits and studied the growth of the contralateral kidney. Thirty fetal rabbits underwent in utero uninephrectomies at day 25 of gestation. On gestational day 28, all the fetuses were delivered by cesarean section and the ratios kidney weight/body weight of the operated fetuses were compared to those of control littermates. The kidneys were then analysed by histology. A significant increase in renal weight was observed. The histological study of the remaining kidneys indicated a statistically significant increase of the glomerular area which confirmed the renal hypertrophy. This experiment demonstrates the capacity for the rabbit to develop in utero compensatory renal growth.

Peripheral odontogenic keratocyst.

The gingival cyst of the adult exhibits an epithelial lining that is essentially the same as the lateral periodontal cyst. Although the gingival cyst of the adult exhibits some morphologic variability, its lining is generally considered to be nonkeratinized. Nonetheless, rare cases of gingival cyst of the adult that exhibit a keratinized epithelial lining have been reported in the literature. There is now a growing tendency to consider this variant as a separate entity. This article describes six cases of gingival cysts that exhibit the histologic features of the odontogenic keratocyst. Evidence from this series suggests that the biologic behavior of this subset of gingival cysts is different from that of the generic gingival cyst of the adult and that the term peripheral odontogenic keratocyst more accurately describes this entity.

A randomized trial comparing a pentavalent antimonial drug and recombinant interferon-gamma in the local treatment of cutaneous leishmaniasis.

In a randomized prospective trial N-methyl-glucamine antimoniate (Glucantime) and human recombinant interferon-gamma were infiltrated around lesions of cutaneous leishmaniasis caused by Leishmania tropica in Syria. A previous trial had shown that intradermal application of interferon-gamma promoted the healing of similar lesions in the study area. Twenty patients with 38 lesions received 1-3 ml Glucantime and 20 patients with 37 lesions received 25 micrograms of interferon-gamma intradermally once weekly for 5 consecutive weeks. While all lesions treated with Glucantime were free of parasites after the third injection, only 69% of those treated with interferon-gamma were parasitologically cured by week 10. Within 10 weeks, lesions treated with Glucantime healed completely in 29/38, and partially in 9/38, cases, whereas 1/37 and 13/37 lesions treated with interferon-gamma healed completely and partially, respectively. Perilesional application of Glucantime was highly effective and superior to interferon-gamma for treatment of cutaneous leishmaniasis caused by L. tropica.

Effects of intradermal gamma-interferon in cutaneous leishmaniasis.

The clinical and immunological evolution of lesions in cutaneous leishmaniasis was assessed after treatment with human recombinant gamma interferon (rIFN-gamma). 3 weeks after rIFN-gamma treatment of lesions due to Leishmania braziliensis guyanensis, 12/13 had become smaller compared with 6/13 control lesions; only 4 treated lesions were free of parasites. 9 of 13 L tropica lesions treated with rIFN-gamma resolved completely within 4-8 weeks of treatment. An acute inflammatory reaction around treated lesions was more common in lesions due to L tropica. There were no other local or systemic adverse reactions. Histological and immunohistochemical studies indicate that local application of rIFN-gamma enhances cell-mediated immune responses and thus promotes healing of cutaneous leishmaniasis.