RESUMEN
PURPOSE: Mandibular fractures are common facial injuries. Classifications are diverse and sometimes correlated with specific treatment modalities. Osteosynthesis using plate and screws is the standard method of fracture treatment. To evaluate the outcome of such fracture management in our clinic, we developed a numeric scoring system for mandibular fractures and investigated the relationship between the scoring of the fracture being treated and the incidence of complications after surgical treatment. PATIENTS AND METHODS: Seventy-six adult patients treated over a 2-year period were evaluated, and the fractures were classified using the mandibular trauma score. This score was based on clinical and radiologic evaluation of each fracture line and ranks from 0 to 15 points. Osteosynthesis was performed using the AO plate systems. Patients were followed-up postoperatively for the presence of complications. RESULTS: During the 2-year period, 76 patients with 134 fractures underwent plate osteosynthesis. Fracture scoring indicated a homogeneous distribution between uncomplicated and severe fractures. The incidence of complications increased with the fracture severity, assessed by the fracture score index. Severe fractures showed fewer complications when treated with a rigid plate system, whereas low-score fractures showed better results when treated with less rigid systems. CONCLUSIONS: The numeric scoring system for mandibular fractures allows an objective and standardized assessment of the degree of severity of a fracture and may facilitate decisions about the use of specific treatment modalities.
Asunto(s)
Fracturas Mandibulares/complicaciones , Índices de Gravedad del Trauma , Heridas no Penetrantes/complicaciones , Adulto , Femenino , Humanos , Incidencia , Masculino , Fracturas Mandibulares/diagnóstico , Fracturas Mandibulares/epidemiología , Fracturas Mandibulares/cirugía , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Pronóstico , Heridas no Penetrantes/diagnóstico , Heridas no Penetrantes/cirugíaRESUMEN
Small amounts of magnesium are always detectable in addition to calcium and phosphorus in mineralized tissues such as dentin or bone. Magnesium has been considered to influence the mineralization process, especially crystal growth. The present study reports on the location and enrichment of magnesium in the newly mineralized dentin by using the high lateral resolution of energy dispersive X-ray microanalysis combined with scanning transmission electron microscopy. To this end, we have used the continuously growing rat incisor as a model for a collagenous mineralizing system. Dental tissue was dissected free and cryofixed in liquid nitrogen-cooled propane. The distribution of elements was measured in freeze-dried ultrathin cryosections. The magnesium distribution of the newly formed dentin area near the predentin area was found to be inhomogeneous. In certain small dentin areas, characteristical magnesium enrichments were observed. Further, high magnesium-to-phosphate molar ratios were found in these areas, and these were correlated with low calcium-to-phosphate molar ratios. Our results support the theory that magnesium is involved in the process of biological apatite crystal formation.
Asunto(s)
Dentina/química , Incisivo/química , Magnesio/análisis , Calcificación de Dientes , Animales , Calcio/análisis , Microscopía Electrónica de Transmisión de Rastreo , Fósforo/análisis , Ratas , Ratas Sprague-DawleyRESUMEN
Matrix vesicles (MVs) induce the primary mineralization in collagen-rich hard tissues such as bone, mineralizing cartilage and dentine. Calcium and phosphate ions accumulate at the inner MV membrane. This accumulation takes place in association with phospholipids alone and/or in association with Annexin V, which displays Ca ion channel activity when inserted in membranes; consequently, Annexin V may be involved in Ca uptake by matrix vesicles. The first crystal nuclei are formed at these macromolecules of the MV inner membrane. They grow to stable nanometre-sized particles, dots, which coalesce to form chains of dots along the macromolecules of the MV inner membrane. At the same time, or shortly afterwards, chains of these Ca phosphate dots also develop inside the MVs. The measured centre-to-centre distances between these dots represent approximately the distances between the nucleating sites, called active sites, along the MV matrix molecules. The mineralization does not stop at the MV membrane but expands continuously into the extravesicular region in radial directions to form nodules. These radiating Ca phosphate chains, which coalesce to form needles, are composed of such primary dots, which have developed at the nucleating sites of the corresponding macromolecules.
Asunto(s)
Matriz Ósea/metabolismo , Calcificación Fisiológica/fisiología , Placa de Crecimiento/metabolismo , Animales , Matriz Ósea/ultraestructura , Fosfatos de Calcio/metabolismo , Cristalización , Matriz Extracelular/metabolismo , Microscopía Electrónica , Modelos Biológicos , Fosfolípidos/metabolismo , Ratas , Ratas WistarRESUMEN
Routinely formalin-fixed and paraffin-embedded material of 22 squamous cell carcinomas of the floor of the mouth (T2NoMo, Ro), together with adjacent dysplastic or normal mucosa, were immunohistochemically investigated using a panel of four anti-p53 antibodies (CM1, PAb1801, DO7, PAb240) subsequent to wet autoclave pretreatment for antigen retrieval. p53 immunoreactivity was detected in 9/22 (40%) carcinomas with PAb1801 and DO7 antibodies, and in 8/22 cases using CM1 and PAb 240. p53-positive tumour cells accumulated predominantly at the invasive front of the carcinomas. A focal or scattered p53 immunoreactivity was observed in the adjacent normal and/or dysplastic mucosa in 17/22 (77%) cases using both CM1 and PAb1801 antibodies, in 10/22 with DO7, and in 8/22 with PAb240. This study has demonstrated examples of different p53 immunophenotypes in the non-tumorous and neoplastic oral mucosa of the same patient without significant correlation to the clinicopathological parameters studied.