Bernardo Ferreira Brasileiro

An In Vitro Evaluation of Rigid Internal Fixation Techniques for Sagittal Split Ramus Osteotomies: Advancement Surgery

PURPOSE This in vitro investigation was developed with the purpose of comparing the biomechanical features of 3 different methods of rigid internal fixation for sagittal split ramus osteotomies for mandibular advancement. MATERIALS AND METHODS Rigid internal fixation techniques included a 4-hole plate and 4 monocortical screws (miniplate group), a 4-hole plate and 4 monocortical screws with 1 additional bicortical positional screw (hybrid group), and 3 bicortical positional screws in a traditional inverted-L pattern (inverted-L group). Screws and miniplates were made of titanium and from a 2.0-mm system (MDT, Rio Claro, SP, Brazil). Sixty polyurethane replicas of human hemimandibles (Nacional, Jaú, SP, Brazil) were used as substrates, simulating a 5-mm advancement surgery by a sagittal split ramus osteotomy. They were adapted to a test support, and were submitted to lateral torsional forces on the buccal molar surface and vertical cantilever loading on the incisal edge by an Instron 4411 mechanical testing unit (Instron, Norwood, MA) for recording peak loading at 1 mm, 3 mm, 5 mm, and 10 mm of displacement. Each group was formed by 10 replicas, subjected to a linear noncyclical testing only once. Means and standard deviation were analyzed using analysis of variance and Tukey tests, with a 5% level of significance. Testing failures were also recorded. RESULTS The miniplate group showed lowest load peak scores (P < .01) when compared with the other fixation techniques, irrespective of the direction of force. The inverted-L group showed higher resistance (P < .01) than the hybrid group when vertical forces were applied. For molar load, the hybrid and inverted-L groups showed no significant difference. CONCLUSIONS For mandibular advancement surgery of 5 mm, it was concluded that the rigid internal fixation technique for sagittal split ramus osteotomies based on 3 bicortical screws in the inverted-L pattern was the most stable in a laboratory environment. Furthermore, the results suggested that installation of a bicortical positional screw in the retromolar region may significantly optimize the resistance of the miniplate and monocortical screw fixation.

Pigmented villonodular synovitis of the temporomandibular joint: case report and review of the literature

Pigmented villonodular synovitis (PVNS) is an aggressive proliferative lesion that usually involves the synovial tissues of big joints. To date, there are ∼52 cases of PVNS affecting the temporomandibular joint reported in the English-language literature, about one-third of them exhibiting intracranial involvement. We herein describe an additional case of PVNS of the temporomandibular joint with skull base invasion affecting a 26-year-old male patient and discuss its clinicopathologic features considering previously published cases. Histopathology and imaging evaluation are important for the diagnosis of PVNS, which should be included in the differential diagnosis of preauricular aggressive swellings.

Caso familiar de nevo branco esponjoso oral: uma rara condição hereditária

White sponge nevus (WSN) is an autosomal dominant skin disorder characterized by white, corrugated and diffuse plaques mainly affecting the oral mucosa. The condition has a high penetrance and variable expressivity, but familial reports are uncommon. This report presents a familial case of WSN in which two sisters are affected by the disorder.

Traumatic ulcerative granuloma with stromal eosinophilia of the palate showing an angiocentric/angiodestructive growth pattern

Traumatic ulcerative granuloma with stromal eosinophilia (TUGSE) is a benign, self-limiting lesion of the oral mucosa with unknown pathogenesis. A 65-year-old male patient presented with an ulcerative palate lesion, which on microscopic examination exhibited an exuberant polymorphic lymphoid proliferation, numerous eosinophils, and extensive vascular destruction. The atypical lymphoid cells infiltrating the medium-sized vessels showed positivity for CD3, CD30, and granzyme B, implicating an activated cytotoxic T-cell phenotype. The lesion diagnosed as TUGSE achieved complete resolution within 3 months. This unusual presentation has expanded the spectrum of oral CD30+ T-cell atypical infiltrates and must be distinguished from lymphomas showing angiocentric/angiodestructive growth pattern.