Analysis of 115 Mandibular Angle Fractures Paza, Aleysson O., PhD, MS, DDS; Abuabara, Allan, DDS; Passeri, Luis A., PhD, MS, DDS
Journal of oral and maxillofacial surgery,
2008, 2008-Jan, 2008-1-00, Volume:
66, Issue:
1
Journal Article
Peer reviewed
Purpose This retrospective study reviewed cases of fractures of the mandibular angle to identify personal data, social traits, fracture characteristics, treatment modalities, and postoperative ...complications. Patients and Methods From April 1999 until July 2004, 114 patients were treated for 115 fractures of the mandibular angle by the Division of Oral and Maxillofacial Surgery at Piracicaba Dental School-Unicamp, in Brazil. Results More angle fractures were observed in Caucasian (55%) men (89%) with some kind of drug addiction (62%). Patient mean age was 27 years. The majority of fractures in this study were sustained in altercations, including gunshot wounds (43%), followed by vehicle accidents, including bicycles and being struck by a car (39%). Open fractures were the most frequent (90%), with prevalence of the left side (57%). Only 1 patient sustained bilateral angle fractures. Ninety-seven patients (85%) underwent open reduction. Complications occurred in 19 patients (17%); 10 (9%) were infections. Of the total number of complications, 3 underwent another surgical intervention for refixation. The factors that contributed to the development of postoperative complications were social risks that included alcohol abuse, smoking, and intravenous and nonintravenous drug abuse. Conclusions Angle fracture management outcomes are affected by many factors beyond method of fixation.
Purpose The correction of maxillomandibular deformities may require maxillary osteotomy procedures that usually present low rates of postoperative complications, such as maxillary sinusitis. The ...present study evaluated the incidence of maxillary sinusitis after Le Fort I osteotomy in 21 adult patients who underwent maxillary surgery (Le Fort I osteotomy) or bimaxillary surgery (Le Fort I osteotomy plus sagittal mandibular osteotomies) for correction of dentofacial deformities. Patients and Methods Verification of the presence of maxillary sinusitis was assessed through a brief questionnaire, x-rays (Waters views), and nasal endoscopy before surgery and 6 to 8 months after surgery. Results Analysis of results showed an incidence of 4.76% of maxillary sinusitis as a postoperative complication in the studied population. Conclusion Symptomatic patients with a positive radiographic finding or an increased risk for postoperative sinusitis will benefit from endoscopic evaluation to aid in treatment planning and follow-up.
Large-Area SiPM Pixels (LASiPs) in SPECT Wunderlich, C.; Guberman, D.; Paoletti, R. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
March 2023, 2023-03-00, Volume:
1048
Journal Article
Peer reviewed
A standard camera for Single Photon Emission Computed Tomography (SPECT) contains 50–100 photomultiplier tubes (PMTs). It is shielded by a thick layer of lead which makes it heavy and bulky. Its ...weight and size could be significantly reduced if replacing the PMTs by silicon photomultipliers (SiPMs). However, one would need a few thousands channels to fill a camera with SiPMs due to their small sensitive area. Alternatively, we propose to use Large-Area SiPM Pixels (LASiPs), built by summing individual currents of several SiPMs into a single output. We extended the simulation of a small camera employed with LASiPs that was presented in Guberman et al. (2021) to a large camera. The extension allowed us to study the feasibility of using larger LASiPs in a full-body SPECT camera. We found an intrinsic spatial resolution of ∼4 mm for a simulated pixel summing 25 SiPMs including SiPM noise at room temperature. Reducing the dark count rate (DCR) could improve the intrinsic spatial resolution to ∼3 mm.
•Simulations of large SPECT camera with SiPM pixels including noise.•Study of impact of pixel size, shape and noise on performance.•SiPM pixel of 9 cm2 provides acceptable spatial resolution.•Reducing dark counts by cooling improves significantly resolution.
Abstract Obstructive sleep apnoea (OSA) results from the recurrent collapse of the upper airway during sleep. Nasal abnormalities influence the stability of the pharynx. The aim of this study was to ...evaluate the volumetric and anatomical changes of the nasal cavity in patients with OSA. The Nasal Obstruction Symptom Evaluation (NOSE) scale was used to grade nasal obstruction. Sleep-related breathing disorders were evaluated by polysomnography. The nasal airway volume was obtained from computed tomography scans through volumetric reconstruction of the nasal airway. Alterations to the nasal anatomy were identified by nasal fibre-optic endoscopy. Ninety-four patient charts were analyzed. The final sample comprised 32 patients with severe OSA, 16 with moderate OSA, 23 with mild OSA, and 20 without OSA. Three groups were established based on nasal obstruction and OSA. The groups were compared for nasal airway volume ( P = 0.464) and body mass index ( P = 0.001). The presence of nasal septum deviation and inferior turbinate hypertrophy were related to the NOSE score ( P = 0.05 for both), apnoea–hypopnoea index ( P = 0.03 and P = 0.05, respectively), and nasal airway volume ( P = 0.71 and P = 0.78, respectively). In this nasal airway evaluation of OSA patients, the presence of sites of obstruction was correlated with the severity of OSA; this was not the case for the evaluation of the nasal airway volume dimensions.
Abstract The surgical treatment of mandibular condyle fractures currently offers several possibilities for stable internal fixation. In this study, a finite element model evaluation was performed of ...three different methods for osteosynthesis of low subcondylar fractures: (1) two four-hole straight plates, (2) one seven-hole lambda plate, and (3) one four-hole trapezoidal plate. The finite element model evaluation considered a load applied to the first molar on the contralateral side to the fracture. Results showed that, although the three methods are capable of withstanding functional loading, the lambda plate displayed a more homogeneous stress distribution for both osteosynthesis material and bone and may be a better method when single-plate fixation is the option.
Abstract This retrospective study evaluated the nasolabial changes in patients who underwent surgically assisted rapid maxillary expansion (SARME) using two different approaches. Nineteen patients ...were included in the study, divided into two groups according to the kind of surgical approach performed: group 1 (n = 9), SARME performed through the standard Le Fort I circumvestibular approach followed by the alar base cinch, and group 2 (n = 10), SARME performed through a subtotal vestibular approach associated to a V-shaped incision at the maxillary midline in the labial frenulum region, without alar base cinch. Measurements of width, length, and nasal projection as well as upper lip length were taken from cone beam tomographic images obtained before surgery (T1) and 6 months postoperatively (T2). Both groups presented an increase in the alar base width postoperatively ( P < 0.05). The approach used in group 2 resulted in smaller changes in the alar base width as measured at the superior alar curvature ( P < 0.05). Nasal length and projection and upper lip length were not altered by SARME. The type of surgical approach influenced nasolabial changes, but did not eliminate increase in width of the alar base.
This study established cone beam computed tomography (CBCT)-based cephalometric norms for Brazilian adults, including the assessment of sexual dimorphism. An observer performed McNamara’s ...cephalometric analysis twice on 60 CBCT datasets acquired from patients with a normal dental occlusion, divided equally into two groups by sex. Welch’s t-test was applied to assess differences between the sexes in hard tissue cephalometric measurements, and Dahlberg’s formula was used to calculate measurement error introduced by the observer. The cephalometric measurements of effective mandibular length, effective midfacial length, maxillomandibular differential, and lower anterior facial height presented sexual dimorphism. Linear measurements had error ≤0.78mm, and angular measurements had error ≤1.24°. The results show that (1) the CBCT-based cephalometric norms established in this study are reliable for use by researchers and clinicians, and (2) Brazilian adult males and females have similar craniofacial morphology, with males possessing larger jaws than females.
Abstract Carotid cavernous sinus fistula is an abnormal vascular interconnection between a branch of the carotid artery and the cavernous sinus. This is an uncommon complication of craniofacial ...injuries, as it occurs in only 0.17–0.27% of cases, according to the literature. The differential diagnosis should include superior orbital fissure syndrome, orbital apex syndrome, orbital haematoma and cavernous sinus thrombosis. The case is reported of an 18-year-old white woman who was involved in a motor vehicle accident. Clinical examination revealed only mandibular fractures, with the absence of skull-base, mid-face or any other fractures. Two days after the trauma, her condition deteriorated, and extraocular movements were totally absent. Magnetic resonance angiographic scanning was performed, and a carotid cavernous sinus fistula was found. This was treated by embolization resulting in restoration of eye movement and vision.
Abstract This study involved a retrospective evaluation of patients subjected to surgery for dentofacial deformities treated without induced controlled hypotension (group I, n = 50) and a prospective ...evaluation of patients who were subjected to surgery under hypotensive general anaesthesia (group II, n = 50). No statistical differences were found between the study groups with regard to the duration of surgery. However, there were statistically significant differences in the need for blood transfusion and the occurrence of bradycardia during the maxillary down-fracture. Hypotensive anaesthesia decreased the need for a blood transfusion and the occurrence of bradycardia, and is therefore considered highly beneficial for patients undergoing orthognathic surgery.
We present a detailed study, done in the framework of the INFN 2006 Roadmap, of the prospects for e+e- physics at the Frascati National Laboratories. The physics case for an e+e- collider running at ...high luminosity at the φ resonance energy and also reaching a maximum center of mass energy of 2.5 GeV is discussed, together with the specific aspects of a very high luminosity τ-charm factory. Subjects connected to kaon decay physics are not discussed here, being part of another INFN Roadmap working group. The significance of the project and the impact on INFN are also discussed. All the documentation related to the activities of the working group can be found in http://www.roma1.infn.it/people/bini/roadmap.html.
PDF
