Search results for " augmentation"
showing 10 items of 116 documents
Intra-neuronal Competition for Synaptic Partners Conserves the Amount of Dendritic Building Material
2017
Brain development requires correct targeting of multiple thousand synaptic terminals onto staggeringly complex dendritic arbors. The mechanisms by which input synapse numbers are matched to dendrite size, and by which synaptic inputs from different transmitter systems are correctly partitioned onto a postsynaptic arbor, are incompletely understood. By combining quantitative neuroanatomy with targeted genetic manipulation of synaptic input to an identified Drosophila neuron, we show that synaptic inputs of two different transmitter classes locally direct dendrite growth in a competitive manner. During development, the relative amounts of GABAergic and cholinergic synaptic drive shift dendrit…
Distance of the alveolar antral artery from the alveolar crest. Related factors and surgical considerations in sinus floor elevation
2016
Background In a variable proportion of maxillary sinuses alveolar antral artery is located close to the residual ridge, increasing the chances for haemorrhagic complications during sinus floor elevation procedures. Material and Methods Retrospective observational study of CBCT explorations performed for implant-treatment planning. The upper first molar area was selected for this study. The relative uncertainty (standard deviation of the measurement divided by its mean and expressed as a percentage from 0% to 100%) was chosen for determining the observational errors. For modeling the chances of AAA detection, the generalized additive models (GAM) approach was chosen. Results A total of 240 m…
Histopathological comparison of healing after maxillary sinus augmentation using xenograft mixed with autogenous bone versus allograft mixed with aut…
2018
To compare the clinical and histologic outcomes of two different grafting materials (allograft and xenograft) when combined with autogenous bone and covered with a collagen membrane for sinus augmentation. MATERIAL AND METHODS: A parallel case series of fourteen patients in need of a unilateral sinus augmentation was evaluated in this study. Seven patients received a graft composed by autologous cortical bone (ACB) and anorganic bovine bone in a ratio of 1:1; the other seven patients received ACB mixed with an allograft in the same ratio. Bone biopsies were obtained 6 months after sinus augmentation at the time of implant placement. Comparative histomorphometrical, histopathological, and im…
Treatment of intrabony defects using guided tissue regeneration and autogenous spongiosa alone or combined with hydroxyapatite/beta-tricalcium phosph…
2007
The aim of this case-control study was to investigate the clinical regeneration of deep intrabony defects using guided tissue regeneration (GTR) with autogenous spongiosa (ASB) alone or using GTR with a mixture of ASB with a bovine-derived xenograft (BDX) or a synthetic composite bone substitute (hydroxyapatite/beta-tricalcium phosphate [HA/beta-TCP]).Sixty-four patients with a total of 93 intrabony defects of 2- or 3-wall morphology and an intrabony component (IC)or=4 mm participated in this study. Defects were treated with a bioabsorbable membrane and ASB alone or ASB mixed with HA/beta-TCP or BDX. Clinical parameters measured at baseline and 12 months after surgery included IC, bleeding …
Volume stability of hydroxyapatite and β-tricalcium phosphate biphasic bone graft material in maxillary sinus floor elevation: a radiographic study u…
2015
Objectives The purpose of this study was to confirm volume stability of biphasic calcium phosphate (BCP) through the changes of grafted volume over the time by 3D CT analyzing software program. Patients and Methods Fifteen patients, 16 sinuses who were scheduled a staged implantation through sinus floor elevation (SFE)–lateral window technique from 2009 to 2011 were included in the study. Of the 15 patients, eight were male and seven were female (mean age 50.1). For sinus floor augmentation, BCP with local blood was packed loosely into the maxillary sinus and the grafted site was covered with a collagen membrane. For the evaluation of volume change, 3D CBCT scans were taken five times at pr…
Vertical Mandibular Alveolar Bone Distraction and Dental Implant Placement: A Case Report
2006
Abstract Extensive bone defects complicate the adequate placement of dental implants and the required angulation. In such cases, alveolar-ridge augmentation techniques such as guided bone regeneration, particulate or block grafting, and alveolar bone distraction are needed. The present study describes a case in which a large vertical bone defect in the anterior mandibular zone was corrected via vertical alveolar bone distraction. Six dental implants were posteriorly placed for implant-supported restoration of the mandible, with early implant loading. The clinical and radiologic control showed good implant and soft tissue conditions 12 months later.
Results of oral implant–supported prostheses after mandibular vertical alveolar ridge distraction: a propos of 54 sites
2012
Objective The aim of this study was to present retrospective long-term results of oral implant–supported prostheses after mandibular vertical alveolar ridge distraction. Study Design Patients who had alveolar mandibular distraction before oral rehabilitation from 1999 to 2009 were retrospectively reviewed. Results Fifty-four distractions were performed in 25 women and 12 men with a mean age of 51.7 years. Seventeen patients had bilateral distraction. Most of the distracted sites were posterior. Global major complications were major misdirection (3.7%), fracture (3.7%), and permanent alveolar nerve paresthesia (1 patient). All of the patients experienced osseous improvement. Mean height of t…
Mandibular connective tissue pedicle flaps in implant dentistry: report of three cases.
2007
Abstract An increase in soft tissues and alveolar bone in the anterior mandibular area between the canines is necessary to achieve a good esthetic result. The present article describes a technique for gaining bone volume and soft tissue to cover bone defects that would otherwise compromise the final result of prosthetic implant restoration in the anterior mandible. Three patients with anterior mandibular atrophy caused by loss of the mandibular incisors are presented. Particulate autologous bone grafting, the raising of a pediculate connective tissue flap to increase soft tissue, and implant placement were carried out simultaneously. After 2 years of follow-up, the implants were in good cli…
Vertical guided bone regeneration with bioabsorbable barriers.
2007
Guided bone regeneration (GBR) is a very useful surgical technique to increase limited alveolar bone for implant placement. The use of non-resorbable barriers is well established; however, bioabsorbable collagen membranes may simplify the surgical technique and make it more predictable.Vertical ridge augmentation was performed on 11 patients at the time of implant placement. The part of the implant out of bone was covered with autogenous bone/graft, and a slow-resorption collagen membrane was placed on top. Gingival tissues were closed with horizontal mattress and interrupted sutures. Second-stage surgery was performed 4 to 6 months later, and healing abutments were placed. The length of th…
Implant treatment planning regarding augmentation procedures: panoramic radiographs vs. cone beam computed tomography images.
2015
Objectives To evaluate the impact of cone beam computed tomography (CBCT) imaging on treatment planning regarding augmentation procedures for implant placement. Material and methods Panoramic radiographs and CBCT images of 40 patients requesting single-tooth implants in 59 sites were retrospectively analyzed by six specialists in implantology, and treatment planning was performed. Therapeutic recommendations were compared with the surgical protocol performed initially. Results Bone height estimation from panoramic radiographs yielded to higher measures and greater variability compared to CBCT. The suggested treatment plan for lateral and vertical augmentation procedures based on CBCT or pan…