Xenograft materials in maxillary sinus floor elevation surgery: a systematic review with network meta-analyses.

A systematic review and network meta-analysis was conducted to compare different commercially available xenograft materials used in maxillary sinus floor elevation surgery (MSFES). Embase, PubMed, the Cochrane Library, Web of Science, Scopus, LILACS, and grey literature were searched up to 13 July 2020. Only randomised controlled trials (RCTs) were included. A frequentist network meta-analysis using a random effects model compared different commercially available xenograft materials. The primary outcomes were the percentage of newly-formed bone and residual bone-substitute rate. Both were measured by histomorphometric analysis from bone biopsies obtained during preparation of the implant site. Of the 659 studies initially identified, 11 involving 242 MSFES were included in the quantitative analyses. A total of six bone-substitute materials were analysed (Bio-Oss® (Geistlich Pharma), InduCera® Dual Coat, Lumina-Bone Porous® (Critéria), Osseous® (SIN - Sistema de Implantes Nacional), THE Graft® (Purgo Biologics), and Osteoplant Osteoxenon® (Bioteck)). The P-score estimation showed that Osteoplant Osteoxenon® produced the most newly-formed bone and reabsorbed faster than other xenograft materials after six months. The combination of Bio-Oss® plus bone marrow aspirate concentrate (BMAC) significantly increased the percentage of newly-formed bone compared with Bio-Oss® alone. In contrast, the addition of Emdogain® (Straumann) and leucocyte and platelet-rich fibrin (L-PRF) to Bio-Oss® did not significantly improve the amount of regenerated bone. Study-level data indicated that the percentage of newly-formed bone differs among commercially available xenograft materials. Osteoplant Osteoxenon® seems to result in the highest amount of new bone in MSFES.

Histomorphometric evaluation of different grafting materials used for alveolar ridge preservation: a systematic review and network meta-analysis.

In this systematic review and network meta-analysis including only randomized clinical trials (RCTs), different grafting materials used in alveolar ridge preservation after tooth extraction were analysed, focusing on histomorphometric new bone formation (NBF) in core biopsies obtained during implant placement. The PubMed, Embase, Cochrane Library, Web of Science, Scopus, and LILACS databases, as well as the grey literature, were searched for published and unpublished trials (from database inception to January 14, 2019). The primary outcome was the percentage of NBF. The secondary outcomes were the percentage of residual biomaterial and the percentage of soft tissue. An arm-based network meta-analysis was performed. The rank of intervention efficacy was obtained to measure the probability of each biomaterial being ranked first across all interventions. A total of 1526 studies were found, of which 38 were included for quantitative analysis. Three trials were rated as having a high risk of bias and 35 trials as having an unclear risk of bias. The network meta-analysis showed that nine grafting materials decreased NBF and 25 did not decrease NBF. The grafting material with the highest amount of NBF was plasma rich in growth factors. Due to the lack of studies with a low risk of bias, further RCTs are needed for definitive conclusions.

Randomized double-blind clinical trial evaluation of bone healing after third molar surgery with the use of leukocyte- and platelet-rich fibrin.

The objective of this study was to evaluate the use of leukocyte- and platelet-rich fibrin (L-PRF) in bone healing after mandibular third molar extraction. In this prospective, double-blind, split-mouth study, 34 extractions were performed. On one side, the socket was sutured primarily (control side); on the other side, L-PRF was inserted before suturing. The patients were assessed for postoperative bone regeneration, pain and soft tissue healing. The primary outcome was bone regeneration, which was performed through tomographic evaluation in the immediate postoperative period and 3 months after the procedure. The ITK-SNAP software was used for image evaluation by the intensity of grey of each voxel. Pain was analysed using a visual analogue scale (VAS), and soft tissue healing was analysed both based on the modified healing index of Landry et al., and by comparing pre- and postoperative periodontal probing at the distal of the lower second molar. The application of L-PRF improved bone density, which was higher in test group (p=0.007). There was no statistical difference related to pain or soft tissue between the groups (p>0.05). There was evidence for improved bone healing in response to L-PRF. However, to better understand the effect of L-PRF more clinical trials with larger samples are necessary.

Platelet-rich fibrin in oral surgical procedures: a systematic review and meta-analysis.

The effect of platelet-rich fibrin (PRF) in enhancing the healing after oral surgical interventions is still a matter of debate. The purpose of this study was to identify instances where PRF has been shown to be effective in oral surgical procedures. A comprehensive literature search was performed up to 2017 on PubMed/MEDLINE, Cochrane Library, Web of Science, Scopus and LILACS databases and grey literature. The full-text of potentially relevant studies were reviewed and only randomized clinical trials (RCTs) were included. A total of 559 studies were found, of which 30 were included for qualitative analysis and 13 for quantitative analysis. Three review authors assessed the risk of bias independently. The available literature suggests that PRF has a positive effect in improving alveolar preservation on extraction sockets and around dental implants. The qualitative analysis showed a significantly better effect of PRF in promoting bone regeneration for alveolar cleft reconstruction. The meta-analysis for third molar surgery showed a decrease in prevalence of alveolar osteitis. PRF increased implant stability 1 week and 1 month after surgery (P=0.0005 and 0.0003). Due to the lack of studies with low risk of bias and a limited number of patients available, further RCTs are needed to confirm these results.

Comparison of the accuracy of maxillary position between conventional model surgery and virtual surgical planning.

The aim of this study was to determine whether virtual surgical planning (VSP) is an accurate method for positioning the maxilla when compared to conventional articulator model surgery (CMS), through the superimposition of computed tomography (CT) images. This retrospective study included the records of 30 adult patients submitted to bimaxillary orthognathic surgery. Two groups were created according to the treatment planning performed: CMS and VSP. The treatment planning protocol was the same for all patients. Pre- and postoperative CT images were superimposed and the linear distances between upper jaw reference points were measured. Measurements were then compared to the treatment planning, and the difference in accuracy between CMS and VSP was determined using the t-test for independent samples. The success criterion adopted was a mean linear difference of <2mm. The mean linear difference between planned and obtained movements for CMS was 1.27±1.05mm, and for VSP was 1.20±1.08mm. With CMS, 80% of overlapping reference points had a difference of <2mm, while for VSP this value was 83.6%. There was no statistically significant difference between the two techniques regarding accuracy (P>0.05).

Evaluation of postoperative complications after mandibular third molar surgery with the use of platelet-rich fibrin: a systematic review and meta-analysis.

The current literature was reviewed to analyze the effects of platelet-rich fibrin (PRF) on postoperative complications after mandibular third molar surgery (pain, alveolar osteitis, swelling, and bone healing). A comprehensive literature search was performed up to 2016 in the PubMed/MEDLINE, Cochrane Library, LILACS, and ScienceDirect databases and the grey literature. Additional records were identified through manual and reference searches. The full-text articles of potentially relevant studies were reviewed; only randomized clinical trials were included. Two review authors assessed the risk of bias independently. A total of 1430 publications were evaluated, of which seven were selected for qualitative analysis and two for quantitative analysis. A meta-analysis was performed only for alveolar osteitis, due to the considerable heterogeneity among studies for the other outcome variables. There were 485 extractions (243 test, 242 control) in 280 patients. PRF appeared to accelerate healing in mandibular third molar surgery, reducing postoperative pain and swelling. Quantitative analysis showed a decrease in prevalence of alveolar osteitis (odds ratio 0.31, 95% confidence interval 0.13-0.77, Z=2.54, P=0.01). Although more clinical trials of a better design and with larger samples are necessary to allow definitive conclusions to be drawn, PRF is a potentially useful biomaterial.

Effects of surgical correction of class III malocclusion on the pharyngeal airway and its influence on sleep apnoea.

The objective of this study was to evaluate, through cone beam computed tomography, the immediate changes in pharyngeal airway space (PAS) after orthognathic surgery in class III patients, and to determine the influence of surgery on the development of obstructive sleep apnoea hypopnoea syndrome (OSAHS). A prospective study was conducted; 33 patients were divided into three groups: mandibular setback surgery (nine patients), bimaxillary surgery (18 patients), and maxillary advancement surgery (six patients). PAS measurements obtained pre- and postoperatively were compared using the t-test. All patients were assessed clinically for OSAHS before surgery and at 6 months postoperative using the Berlin questionnaire and a combined clinical assessment, which included the assessment of OSAHS symptoms, Epworth Sleepiness Scale score, and body mass index. Patients undergoing isolated mandibular setback surgery demonstrated a decrease in total PAS volume, in hypopharynx volume, and in minimum cross-sectional area of the pharynx immediately after surgery (P<0.05). The clinical analysis did not reveal signs or symptoms of OSAHS in any of the 33 patients. Although patients who underwent mandibular setback surgery alone demonstrated a volume reduction in the PAS and a decrease in minimum cross-sectional area, these reductions were not accompanied by signs or symptoms of OSAHS.

Autologous blood injection for the treatment of recurrent mandibular dislocation.

The purpose of the present study was to evaluate the effectiveness of autologous blood injection in the treatment of recurrent temporomandibular joint dislocation. Eleven patients diagnosed with recurrent dislocation of the joint that could not be self-reduced, received bilateral injections of autologous blood in the superior joint compartment and pericapsular region. During a follow-up period ranging from 24 to 35 months (average 29.6 months), eight patients (72.7%) did not show new episodes of dislocation. The most advocated treatment for recurrent dislocation is eminectomy, which involves a skin incision, with the risk of damaging the facial nerve, requires general anaesthesia, and presents an average success rate of 85% according to the literature. Autologous blood injection is a simple, rapid, minimally invasive, and cost-effective technique, with a low possibility of complications, and is a feasible alternative treatment before surgical intervention.

Traumatic neuroma following sagittal split osteotomy of the mandible.

A 16-year-old male underwent bilateral sagittal split osteotomy of the mandible to correct a mandibular deficiency. Twenty-one years later, a routine panoramic radiograph revealed a radiolucent lesion on the left side of the mandible. The lesion was biopsied. As the patient did not have symptoms and the lesion was connected to the inferior alveolar nerve, the lesion was not totally excised in order to preserve nerve function. The histological features were consistent with traumatic neuroma, and no further surgical procedure was planned.