Search

This study evaluated, by mechanical testing, the strength of four-hole grid plates used for mandibular angle fracture fixation. Much has been discussed about the treatment of mandibular fractures with straight or curved plates. However, there are few studies about the use of grid plates. The geometry of such plates provides three-dimensional stability, resistance against torque associated with a low profile. Ninety polyurethane hemimandibles were used as substratum. The hemimandibles were divided into nine groups and fixation of the fractures was performed varying the type and position of plate and type of screw. An intact hemimandible group was used as control. It was possible to observe that plates positioned at the tension zone present the highest load values, both for dislocations of 3 and 5 mm. There was no statistical difference when plates with or without an intermediate bar were tested. The locking screws were more efficient than the non-locking screws when the plates were positioned at the neutral zone. Results allowed us to conclude that grid plates installed at the tension zone presented greater mechanical efficiency. If grid plates are positioned at the neutral zone, they should have an intermediate bar and be fixed with locking screws.

Made available in DSpace on 2022-04-29T08:32:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-03-01 Objective: The aim of this study was to compare bone formation between 2 distraction osteogenesis protocols by analyzing cone beam computed tomography (CBCT) scan data. Study Design: In this retrospective study, the efficacy of 2 different surgically assisted rapid maxillary expansion protocols (group 1 [G1], 3 × 0.25 mm/d; group 2 [G2], 1 mm start followed by 2 × 0.25 mm/d) was analyzed using CBCT scans obtained at 3 time points: preoperatively (T0), immediately after surgery (T1), and 6 months after surgery (T2). Bone formation at T0, T1, and T2 was analyzed using the Dolphin Imaging 11 program. Results: At T1, both groups had significantly higher bone volume than at T0 (G1, 135.6 vs 124.65 mm3, respectively; G2, 153.49 vs 118.9 mm3, respectively), with no significant difference between groups (P = .6). Moreover, bone density measured in the region of interest was similar between groups at all 3 time points; however, in both groups, bone density was significantly lower at T1 and T2 than at T0 (P < .01), with no difference between T1 and T2. Conclusions: Bone density between the incisors decreased with progressive distraction (i.e., increasing volume), regardless of the distraction protocol used; thus, both protocols can be used safely in clinical practice. Nevertheless, our results indicate that stress should not be applied to the incisors within 6 months of surgery, regardless of the protocol used. Surgeons and orthodontists should therefore consider immature bone formation and avoid using excessive force to close a diastema. Department of Oral and Maxillofacial Surgery Medical University of Vienna. Department of Diagnosis and Surgery Dental School of Araraquara São Paulo State University. Department of Diagnosis and Surgery Dental School of Araraquara São Paulo State University.

Background and Aim Surgically assisted rapid maxillary expansion (SARME) is a surgical technique widely used to correct deficiency of the transverse maxillary dimension. Although some studies investigated the effect of SARME on nasal and facial alterations, there is no evidence that correlates nasal septal deviation (NSD) to SARME as a possible postoperative sequel. The aim of this study is to address and quantify possible variations in the position of the nasal bony septum after SARME and identify any NSD as a postoperative outcome of this surgical technique. Patients and Methods This is a retrospective study, conducted at the Department of Oral and Maxillofacial Surgery of the University Hospital of Araraquara (Unesp, faculty of dentistry), SP, Brazil. Twenty-nine patients who underwent SARME were studied; every patient was evaluated by cone-beam computerized tomography (CBCT) before (T0) and six months after surgery (T1), and we collected the variation of nasal septal position by measuring the distance between the bony septum and the nasal lateral wall. Our measurements were carried out at the level of the head, midpoint and tail of the inferior turbinate. Results A mean NSD ranging from 0.4 to 1.2 mm was measured, and it is more pronounced at the anterior part of the bony septum. Twenty-seven patients (93.1%) presented minor changes in bony septum position; in 2 cases (6.8%), a significant NSD was found (p Conclusion A variation of bony nasal septum position can be expected in any direction after SARME, and it is more pronounced at anterior portion.

Biphenotypic sinonasal sarcoma is a rare and recently recognized entity. It is a low-grade sarcoma which exhibits both neural and myogenic differentiation. The objective of this study is to report a case of a 25-year-old male patient with nasal congestion and bleeding. Computed tomography showed a tumor mass in the nasopharynx. Microscopic analysis showed a cellular proliferation of spindle cells, forming mainly a herringbone-like fascicular growth pattern. Immunohistochemical analysis showed focal positivity for S100, alpha-smooth muscle actin, and calponin, and negativity for desmin, SOX 10, and FXIIIA. We present an uncommon case of biphenotypic sinonasal sarcoma of the nasopharynx and emphasize the importance of recognizing rare entities with impact on the health of these patients.

Necrotizing fasciitis (FN) is a rapidly progressive infection of the deeper tissues with destruction of muscle fascia and a high mortality rate. It is extremely rare and usually it is related to immunosuppression or other systemic debilitating conditions. A 26-year-old white male presented with upper lip edema, with phlogistic signs and infiltration through the infraorbital space along with the presence of tissue necrosis. According to the report, the condition was marked by rapid progression, and the initial manifestation was an acnelike lesion. The treatment was done immediately by incision, drainage, debridement, and installation of drains. The muscle fascia was necrotic, gray, and there was an absence of resistance. Laboratory tests were performed and the microbiologic culture was positive for Staphylococcus aureus. Endovenous antibiotic therapy was administered and the wound was irrigated daily. Healing was completed within a month. NF is a rare infection that must be diagnosed and treated aggressively to avoid tissue loss and to decrease the mortality rate.