1,720,969 research outputs found
Coronectomy of mandibular third molars: A clinical protocol to avoid inferior alveolar nerve injury
No full textCoronectomy is a surgical procedure for the treatment of mandibular third molars in close proximity to the mandibular canal. Unfortunately, often the surgical protocol is not described step by step and it is difficult for the clinician to assess the key factors that are important for the success of this procedure. The aim of this paper is to propose and describe a standardized surgical protocol to improve the success of the technique. The treatment approach, for the most common types of third molars impaction is analysed. Each step of the surgical procedure is described in details and a new type of crown section is proposed. The presented protocol is proposed in order to define a clinical practitioner's guide that could help the surgeon who approaches coronectomy for the first times
INFLUENCE OF SECONDARY WOUND HEALING AFTER MANDIBULAR THIRD MOLAR CORONECTOMY
No full textOur aim was to describe the postoperative morbidity related to secondary wound healing after coronectomy. Ten of 116 patients treated by coronectomy healed by second intention as a result of failed sutures. We made a retrospective analysis after two years to evaluate the postoperative morbidity related to secondary wound healing. The complete closure of the alveolus of the 10 surgical sites was recorded three months after coronectomy. No patients had postoperative infections, dry socket, or pulpitis. All patients were free of symptoms, the retained roots were completely included, and were not detectable with a periodontal probe. The importance of primary wound closure after coronectomy has been stressed as a critical point to avoid postoperative infection of the root. We found that secondary wound healing after coronectomy was not associated with a high postoperative infection rate, but further randomised clinical studies are necessary to confirm the need for primary closure and its relations to the long-term success of the coronectom
Minimally Invasive Approach Based on Pterygoid and Short Implants for Rehabilitation of an Extremely Atrophic Maxilla: Case Report
No full textIntroduction: Extremely atrophic maxillae can be considered the most important indication for three-dimensional maxillary reconstruction. Different bone-augmentation techniques have been suggested to accomplish this. This article illustrates a minimally invasive approach to rehabilitation of the extremely atrophic maxilla. Material and Methods: A 63-year-old male patient was referred for restoration of his totally edentulous maxilla with a fixed full-arch implant-prosthetic rehabilitation. Four short implants in the premaxillary region and 2 longer implants in the pterygomaxillary regions were inserted with piezoelectric implant site preparation. Discussion: At the 1-year follow-up appointment, no clinical or radiographic changes in the soft-tissue contours or crestal bone levels were observed. Conclusion: This surgical approach, based on the combination of short implants in the premaxillary regions and pterygoid implants in the pterygomaxillary regions, represents a way to shorten treatment timing, minimize the risk of surgical complications, and reduce patient discomfort and costs
Evaluation of complication rates and vertical bone gain after guided bone regeneration with non-resorbable membranes versus titanium meshes and resorbable membranes. A randomized clinical trial
Full text linkAbstract
Background
The partial edentulous posterior mandible is often a challenge area that requires a bone reconstructive surgery for implants placement.
Purpose
This RCT was aimed to evaluate complications rate and vertical bone gain after Guided Bone Regeneration (GBR) with dense non-resorbable d-PTFE titanium-reinforced membranes (Group A) versus titanium meshes covered by cross-linked collagen membranes (Group B).
Material and Methods
40 partially edentulous patients with atrophic posterior mandible, were randomly divided into two study group: 20 patients were treated with one stage GBR by means of non-resorbable d-PTFE titanium-reinforced membranes (Group A); and 20 patients, by means of titanium mesh covered by cross-linked collagen membranes (Group B). All complications were recorded, distinguishing between “surgical” and “healing” and between “minor” or “major”. Primary implants stability and vertical bone gain were also evaluated.
Results
In the group A, surgical and healing complication rates were 5.0% and 15.0%, respectively. In the group B, surgical and healing complication rates were 15.8% and 21.1%, respectively. No significant differences between two study group were observed regarding complications rate implant stability and vertical bone gain.
Conclusions
Both GBR approaches for the restoration of atrophic posterior mandible achieved similar results regarding complications, vertical bone gain and implant stability
Evaluation of Crestal Bone Loss Around Straight and Tilted Implants in Patients Rehabilitated by Immediate-Loaded Full-Arch All-on-4 or All-on-6: A Prospective Study
No full textThe aim of this prospective study was to compare implant success rate and crestal bone loss around tilted and straight implants supporting immediate-loading full-arch rehabilitations. Twenty consecutive patients with edentulous jaws treated between June 2013 and July 2015 who satisfied all inclusion and exclusion criteria were included in the study. All patients were rehabilitated through a full-arch restoration supported by 4 or 6 immediately loaded implants. Clinical and radiographic examinations were scheduled every 12 months to evaluate implant success rates and crestal bone levels. Significant differences in crestal bone levels and success rates between straight and tilted implants were investigated by means of independent statistical analysis; differences were regarded as significant if P < .05. Seventy straight and 50 tilted implants were placed to rehabilitate 14 mandibles and 12 maxillae in 20 patients. After a follow-up of 12 to 36 months, survival rate was 97.1% for straight implants and 96.0% for tilted implants; while success rates were 94.3% and 94.0%, respectively. Success and survival rates were not significantly different (P > .05). Change in crestal bone level was 0.5 +/- 0.4 mm for straight implants and 0.6 +/- 0.4 mm for tilted implants (P > .05). Straight and tilted implants seemed to have similar behavior after immediate loading rehabilitations. After functional loading, straight and tilted implants did not differ significantly in clinical outcome
Histomorphometric and Immunohistochemical Evaluation of Bone Healing Around Implants Placed Using Piezosurgery vs Conventional Drills: A Split-Mouth Pilot Study
No full text: This pilot study evaluated and compared histomorphometric and immunohistochemical characteristics of peri-implant bone tissue after implant site preparation using piezoelectric tips versus conventional drills. Six patients with bilateral partial edentulism underwent a split-mouth protocol. Twelve alveolar ridges were randomized into 6 control implant sites prepared using conventional drills (drill group) and 6 test implant sites prepared using piezoelectric implant inserts (piezo group). At 28 days after surgery (T1), single-stage "study fixtures" with 0.5 mm of peri-implant bone tissue were explanted and processed for histological, histomorphometric, and immunohistochemical analysis in both groups. For each sample inflammatory infiltrates, necrotic bone (zone 1), woven and newly formed bone (zone 2), native bone (zone 3), a vascular endothelium differentiation and neo-osteogenesis marker (cluster of differentiation 31 [CD31]), and an osteoblastic cell differentiation and osteogenesis marker (special AT-rich sequence-binding protein 2 [SATB2]) were evaluated. According to their histological bone features, the 3 histologically distinct areas were evident in both groups: zones 1, 2, and 3 according to their histological bone features. Zone 1 showed lower extension in the piezo group than in the drill group (p = .028). Regarding the immunohistochemical markers, in all areas of the piezo group, SATB2 and CD31 were statistically higher than in the drill group. Implant site preparation using piezo surgery results in less bone necrosis, greater osteoblastic activity, and greater vessel proliferation compared with the conventional surgical approach
A Proposal of Pseudo-periosteum Classification After GBR by Means of Titanium-Reinforced d-PTFE Membranes or Titanium Meshes Plus Cross-Linked Collagen Membranes
No full textAfter (GBR) with different devices, a layer of connective tissue calledcan be observed above the newly formed bone. The aim of this study is to evaluate the clinical and histologic features and to suggest a classification of this connective tissue after GBR with nonresorbable membranes or titanium (Ti)-mesh plus resorbable membranes. Forty patients with partial edentulism in the posterior mandible were randomized into two groups: 20 patients were treated by means of Ti-reinforced dense polytetrafluoroethylene (d-PTFE) membrane (group A), while the other 20 patients were treated with Ti-mesh and a cross-linked collagen membrane (group B). After 9 months and during re-opening surgery, bone density and pseudo-periosteum type were recorded. Pseudo-periosteum was classified into Type 1 (no tissue or tissue < 1 mm); Type 2 (regular tissue between 1 and 2 mm); and Type 3 (irregular tissue or tissue > 2 mm). Histologic analyses were performed to identify the features of pseudo-periosteum. Out of 40 patients, 36 (n = 19 in Group A; n = 17 in Group B) with 99 implants were analyzed after GBR and according to the study protocol. The vertical bone gain was 4.2 ± 1.0 mm in Group A and 4.1 ± 1.0 mm in Group B. Group A had a higher bone density and greater amounts of type 1 periosteum than Group B (P = .01 for both). The preliminary results of this study show that both d-PTFE membranes and Ti-mesh plus collagen membranes are two valid options for bone augmentation in the mandible. However, nonresorbable membranes achieve higher bone density and a thinner pseudo-periosteum layer above the newly formed bone
A microcomputed tomography analysis of bone tissue after vertical ridge augmentation with non-resorbable membranes versus resorbable membranes and titanium mesh in humans
No full textGuided bone regeneration is a frequently used surgical procedure for hard tissue reconstruction when horizontal and or/vertical augmentation are needed. The treatment concept is based on the application of occlusive membranes like non-resorbable membranes or titanium mesh plus resorbable membranes. However, there are no studies comparing the microcomputed tomography results for bone obtained using these two procedures, and this was the purpose of the present study
Periodontal Healing Distally to Second Mandibular Molar After Third Molar Coronectomy
No full textPurpose Coronectomy of mandibular third molars is a procedure that still raises a number of questions. The aim of the present study was to answer one unsolved question: the periodontal healing distal to the mandibular second molar after third molar coronectomy. Materials and Methods A prospective cohort study was performed of 30 patients treated at the Unit of Oral and Maxillofacial Surgery of the Department of Biomedical and Neuromotor Science of the University of Bologna. The predictor variables were the probing pocket depth (PPD), the distance between the marginal crest (MC) and the bottom of the osseous defect (BOD), and the distance between the cementum enamel junction (CEJ) and the BOD. These clinical indexes were recorded on 3 points of the distal surface of second molar: the distobuccal (DB), distomedial (DM), and distolingual (DL) sites. The other variables evaluated included root migration and postoperative complications. The Wilcoxon test for paired data and Kendall's tau-b correlation coefficient was used to evaluate all variables. The significance level was set at P = .05. Results The cohort was composed of 30 patients with 34 high-risk mandibular third molars (9 men and 21 women), with a mean age of 28 ± 7 years. At 9 months, a statistically significant reduction in the PPD of 2 ± 3, 1 ± 2, and 2 ± 2 mm and a statistically significant reduction in the MC-BOD distance of 4 ± 4, 4 ± 4, and 4 ± 5 mm for the DB, DM, and DL sites, respectively, was observed (P = .001). Also, the intraoperative CEJ-BOD distance showed a statistically significant reduction for the DB, DM, and DL sites. Conclusions After coronectomy, restoration of a clinical healthy periodontium distal to the second molar was observed. However, further studies are necessary to confirm these preliminary clinical results and to compare periodontal healing between coronectomy and complete extraction
Clinical and volumetric outcomes after vertical ridge augmentation using computer-aided-design/computer-aided manufacturing (CAD/CAM) customized titanium meshes: a pilot study
Full text linkBackground: One of the most recent innovations in bone augmentation surgery is represented by computer- aided-design/computer-aided-manufacturing (CAD/CAM) customized titanium meshes, which can be used to restore vertical bone defects before implant-prosthetic rehabilitations. The aim of this study was to evaluate the effectiveness/reliability of this technique in a consecutive series of cases.
Methods: Ten patients in need of bone augmentation before implant therapy were treated using CAD/CAM customized titanium meshes. A digital workflow was adopted to design virtual meshes on 3D bone models. Then, Direct Metal Laser Sintering (DMLS) technology was used to produce the titanium meshes, and vertical ridge augmentation was performed according to an established surgical protocol. Surgical complications, healing complications, vertical bone gain (VBG), planned bone volume (PBV), lacking bone volume (LBV), regenerated bone volume (RBV), average regeneration rate (RR) and implant success rate were evaluated.
Results: All augmented sites were successfully restored with definitive implant-supported fixed partial dentures. Measurements showed an average VBG of 4.5 ± 1.8 mm at surgical re-entry. Surgical and healing complications
3 occurred in 30% and 10% of cases, respectively. Mean values of PBV, LBV, and RBV were 984, 92, and 892 mm ,
respectively. The average RR achieved was 89%. All 26 implants were successfully in function after 1 year of follow- up.
Conclusions: The results of this study suggest that the bone augmentation by means of DMLS custom-made titanium meshes can be considered a reliable and effective technique in restoring vertical bone defects
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