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Concept: Oral and maxillofacial surgery

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As a result of major ablative surgery, head and neck oncology patients can be left with significant defects in the orofacial region. The resultant defect raises the need for advanced reconstruction techniques. The reconstruction in this region is aimed at restoring function and facial contour. The use of vascularised free flaps has revolutionised the reconstruction in the head and neck. Advances in reconstruction techniques have resulted in continuous improvement of oral rehabilitation. For example, endosteal implants are being used to restore the masticatory function by the way of prosthetic replacement of the dentition. Implant rehabilitation usually leads to improved facial appearance, function, restoration of speech and mastication. Suitable dental implant placement’s site requires satisfactory width, height and quality of bone. Reconstruction of hard tissue defects therefore will need to be tailored to meet the needs for implant placement.The aim of this feasibility study was to assess the compatibility of five standard commercially available dental implant systems (Biomet 3i, Nobel Biocare, Astra tech, Straumann and Ankylos) for placement into vascularised fibula graft during the reconstruction of oromandibular region.Radiographs (2D) of the lower extremities from 142 patients in the archives of the Department of Radiology in University College London Hospitals (UCLH) were analysed in this study. These radiographs were from 61 females and 81 males. Additionally, 60 unsexed dry fibular bones, 30 right sided, acquired from the collection of the Department of Anatomy, University College London (UCL) were also measured to account for the 3D factor.In the right fibula (dry bone), 90% of the samples measured had a width of 13.1 mm. While in the left fibula (dry bone), 90% of the samples measured had a width of 13.3 mm. Fibulas measured on radiographs had a width of 14.3 mm in 90% of the samples. The length ranges of the dental implants used in this study were: 7-13 mm (Biomet 3i), 10-13 mm (Nobel biocare), 8-13 mm (Astra Tech), 8-12 mm (Straumann ) and 8-11 mm (Ankylos).This study reached a conclusion that the width of fibula is sufficient for placement of most frequently used dental implants for oral rehabilitation after mandibular reconstructive procedures.

Concepts: Implants, Dental implant, Oral and maxillofacial surgery, Osseointegration, Free flap, Per-Ingvar Brånemark, Nobel Biocare, University College London

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The aim of this study was to assess the efficacy of a single prophylactic dose of amoxicillin and/or dexamethasone in preventing postoperative complications (PC) after a surgical removal of a single mandibular third molar (M3).

Concepts: Pharmacology, Medicine, Clinical trial, Randomized controlled trial, Clinical research, Placebo, Oral and maxillofacial surgery, Wisdom teeth

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Resorbable screw fixation for orthognathic surgery is widely used in oral and maxillofacial surgery and has several advantages. However, surgeons are concerned about using resorbable screws in orthognathic surgery because of possible postoperative complications such as relapse, screw fracture, and infection. The purpose of this study was to evaluate the skeletal stability of bicortical resorbable screw fixation after sagittal split ramus osteotomies for mandibular prognathism.

Concepts: Surgery, Reconstructive surgery, Dentistry, Oral and maxillofacial surgery, American College of Surgeons, Orthodontics, Microsurgery, Orthognathic surgery

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The premasseter space is a recognized, sub-superficial musculoaponeurotic system (SMAS) soft-tissue space overlying the lower masseter immediately anterior to the parotid. The performance, safety, and effectiveness of composite face lifts are enhanced when the space is used. This has drawn attention to the need for better understanding of the premasseter anatomy above the space.

Concepts: Medicine, Surgery, Physician, Al-Andalus, Plastic surgery, Reconstructive surgery, Oral and maxillofacial surgery, Rhytidectomy

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BACKGROUND: Many Asians receive epicanthoplasty to improve their medial epicanthal fold.Excessive performance of such surgery may cause multiple unwanted results, but there is no report on any restoration method for an overcorrected result of epicanthoplasty. Accordingly, the authors have created a new method for reversely restoring the excessively corrected medial epicanthal fold using skin-redraping epicanthoplasty (Plast Reconstr Surg. 2007;119:703-710). METHODS: During the interval between January 2009 and April 2011, 35 patients received surgery for restoration of the epicanthal fold using the authors' method, which involves sufficiently elevating the skin flap and redraping it to reconstruct the epicanthal fold. This method is very simple to design and perform, and it effectively covers the excessively exposed lacrimal lake. In addition, it can be used independently of the type of prior epicanthoplasty. RESULTS: After the surgery, 2 patients experienced overcorrection, and we repeated the epicanthoplasty. In the other patients, there was no severe complication except for mild redness, a condition that improved after several months. The mean measured distance between the medial canthi after the surgery was 36.8 mm, corresponding to a total lengthening effect of 4.5 mm. This improved the aggressive facial expression caused by the exposed lacrimal lake, and the eyes no longer appeared to be too close together. Moreover, in the case of patients who had more visible scars due to prior epicanthoplasty on the medial epicanthal area, the overall scar length decreased. CONCLUSIONS: This method is simple in design and easy to perform. It can also control the degree of restoration with an additional advantage of reducing a prior scar. Using this method, we could effectively restore the overcorrected epicanthal fold.

Concepts: Causality, Scar, Eye, Skin, Oral and maxillofacial surgery, FN SCAR, 2011, Lacrimal lake

28

Total hip replacement in developmental dysplasia of the hip grade IV of Crowe’s classification presents some difficulties. In this study, we present our results of the treatment for this pathology, also describing the surgical techniques used and the complication we had. In this paper, 18 total hip replacements in developmental dysplasia of the hip Crowe IV were studied clinically and radiologically before and after surgery, with a mean follow-up of 4.2 years (min: 1 year). The average Harris Hip Score improved from 52 to 89. The average leg lengthening was 36 mm. When a subtrochanteric shortening osteotomy was performed, the healing occurred in all cases, in an average time of 5.3 months. At now, the implant survivorship is 100 % (no revision required). The techniques and principles described in this paper allow to achieve good results in this surgery. An accurate preoperative evaluation and the availability of specific materials are also important steps. The subtrochanteric shortening is a safe procedure to avoid neurovascular injuries.

Concepts: Time, Surgery, Hip replacement, Hip, Pelvis, Orthopedic surgery, Oral and maxillofacial surgery, Implant

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This study investigated short- and long-term postoperative skeletal changes following intraoral vertical ramus osteotomy (IVRO) for mandibular prognathism, as determined from lateral cephalograms. The subjects were 20 patients with mandibular prognathism who had undergone surgical orthodontic treatment combined with IVRO. Lateral cephalograms were taken at six time points: 1 month before surgery, and 1 day, 3 months, 6 months, 1 year, and approximately 2 years after surgery. Intermaxillary fixation (IMF) with four monocortical screws was maintained for 1 week in all patients. Mean posterior movement of the menton (Me) was 5.9mm at surgery. 3 months after surgery, the FMA and FH-CorMe angles had increased 6.3 and 6.2 degrees, respectively, indicating clockwise rotation of the distal segment of the mandible. This rotation was observed in all 20 patients, suggesting that postoperative rotation of the mandible in the postoperative short term is likely to occur after IVRO and could be considered an adaptation of the mastication system newly established by surgery. In the long term after IVRO, Me had moved anteriorly by only 0.9mm and the relapse ratio was 15.3%. These findings suggest the excellent long-term stability of surgical orthodontic treatment combined with IVRO in patients with mandibular prognathism.

Concepts: Time, Surgery, Economics, Term, Dentistry, Oral and maxillofacial surgery, Orthodontics, Prognathism

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Abstract Objective: To compare the root development and the growth rate of the mandibular third molar (M3 inf) in individuals where the M3 inf erupted vs individuals exhibiting M3 inf impaction. Materials and Methods: Serial standardized intraoral radiographs (Eggen technique) were taken annually of the mandibular third molar region from 132 subjects (71 male and 61 female) from 15 to 20 years of age. Based on the films, 264 lower third molars were classified into an eruption and an impaction group. Root development was recorded according to a quantitative method described by Haavikko (1970), and the eruption status was analyzed using logistic regression. Results: In total, 155 (59%) of the M3 inf erupted, and 109 (41%) were impacted at age 20. In 44 (33%) patients both M3 inf were impacted, in 21 (16%) patients one tooth was erupted and the contralateral tooth impacted, and in 67 (51%) patients both M3 inf were erupted. The more mature a tooth was at age 15, the higher was the probability of eruption (odds ratio: 3.89, P < .001). The growth rate of the root development stage was statistically significantly associated with the probability of eruption (odds ratio: 10.50, P  =  .041). Conclusions: Delayed mandibular third molar root development is associated with impaction. Radiographs taken at age 15 may predict the risk of impaction and thereby guide decision making for the orthodontist or the oral and maxillofacial surgeon.

Concepts: Logit, Decision theory, Teeth, Molar, Oral and maxillofacial surgery, Wisdom tooth, Mandibular third molar

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The aim of this study was to identify the relative risk of damage to the inferior dental (ID) and lingual nerves in patients undergoing lower third molar removal.

Concepts: Teeth, Oral and maxillofacial surgery, Tongue, Lingual nerve, Inferior alveolar nerve, Wisdom teeth