Assessment of the efficacy of autologous blood preparations in maxillary sinus floor elevation surgery: a systematic review and meta-analysis.

OBJECTIVE: This study aimed to evaluate the efficacy of autologous blood preparations, namely Platelet-Rich Plasma (PRP), Platelet-Rich Fibrin (PRF), and Concentrated Growth Factor (CGF), in maxillary sinus floor elevation surgery. The focus was on their impact on new bone formation, maxillary sinus floor height, and soft tissue healing. METHODS: A systematic search was conducted across PubMed/MEDLINE, Web of Science, Embase, and Scopus databases up to April 2024. This systematic review included both randomized clinical trials (RCTs) and controlled clinical trials (CCTs) that evaluated the efficacy of autologous blood preparations in maxillary sinus floor elevation surgery. The primary outcomes measured were the percentage of new bone formation, maxillary sinus floor height, and he percentage of soft tissue area. Data from the selected studies were extracted and analyzed to determine the impact of autologous blood preparations on these outcomes. The risk of bias was assessed using Cochrane's risk of bias tool and ROBINS-I, and meta-analyses were performed using Review Manager 5.4 software to calculate effect sizes and integrate results from multiple studies. RESULTS: Among the 507 screened articles, 30 studies met the inclusion criteria. The results indicated that the application of PRP significantly increased new bone formation during maxillary sinus floor elevation surgery (primary outcome, MD = 4.40, CI = 0.37 to 8.44, P = 0.03), as well as improving maxillary sinus floor height elevation (secondary outcome, MD = 1.00, CI = 0.78 to 1.23, P < 0.00001). The absence of PRP during surgery had a statistically significant effect on the percentage of soft tissue area (secondary outcome, MD= -5.25, CI= -7.29 to 3.20, P < 0.00001). However, based on the research findings, PRF did not show significant effects on enhancing new bone formation, maxillary sinus floor height elevation, and promoting soft tissue regeneration. CONCLUSIONS: PRP demonstrates efficacy in maxillary sinus floor elevation surgery by enhancing new bone formation and increasing sinus height. Further studies are needed to validate the outcomes of PRF and CGF.

Reamer-scraping and implant-pushing technique for transcrestal sinus floor elevation.

Transcrestal maxillary sinus floor elevation is an effective method to solve the problem of insufficient bone height in the posterior maxillary region. However, current methods, such as osteotome sinus floor elevation, cushioned grind-out technique, Smart Drill technique, etc., require specialized surgical tool boxes. In this article, we introduce a new method of transcrestal maxillary sinus elevation that uses built-in reamers of various implant systems to scrap residual bone at the sinus floor and uses the implant to push the sinus membrane during implant placement. This technique is easy to operate and time saving and has a low rate of sinus membrane perforation. After a one-year follow-up observation of 146 people and 175 implants, the endo-sinus bone gains were 5.00 (4.70, 5.30) mm and 2.10 (1.40, 2.70) mm in the group of 3 mm≤residual bone height (RBH)<5 mm and the group of 5 mm≤RBH<8 mm, respectively, which can meet the clinical requirements of implant stability. This technique is suitable in generalizing dental implantation.

Maxillary Sinus Augmentation with Autogenous Tooth Grafting Material: A Systematic Review.

The aim of this systematic review was to determine whether autogenous tooth grafting material (ATGM) is as safe and effective as other bone substitutes used for maxillary sinus augmentation procedures, evaluating histomorphometric and/or histological data, implant primary stability, associated complications and radiographic bone height measurements. An automated electronic search was conducted using four databases (Medline/PubMed, Scopus, Web of Science and Cochrane Library), supplemented by a manual search, to identify clinical human studies using particulate ATGM for the aforementioned procedure. The included studies had a sample size of at least four patients and were published before 31st July 2024. The Newcastle-Ottawa scale (NOS) and Joanna Briggs Institute (JBI) Critical Appraisal Checklist were used to assess the risk of bias in cohort studies and case series, respectively. Seven studies were included in the descriptive analysis, obtaining 128 participants (46.8% only treated with ATGM) and 192 placed implants. Due to the heterogeneity of the studies, meta-analysis could not be performed. The authors concluded that ATGM appears to be a feasible and safe alternative for maxillary sinus augmentation procedures. These results should be interpreted with caution due to the limited amount of scientific evidence on this topic and the heterogeneity between the included studies.

Randomized controlled trial on the efficacy of a custom-made, fully guided implant system for flapless crestal sinus floor elevation: Accuracy and patient-reported outcomes.

OBJECTIVE: To compare fully guided flapless implant surgery using a light-cured surgical guide (FG group) with partially guided open flap surgery (PG group) in the posterior maxilla when performing simultaneous sinus floor elevation in terms of the accuracy, time requirements, and patient/clinician-reported outcomes (PROMs and CROMs). MATERIALS AND METHODS: In this study, 56 tissue-level implants were placed with crestal sinus floor elevation in 56 patients at single-tooth sites, with 28 implants allocated to the PG group and 28 to the FG group. The deviations of the placed implants from the virtually planned positions were measured at the implant platform and apex and for the angular deviation. The presurgical preparation time and the duration of surgery were measured. PROMs and CROMs were made by administering questionnaires at multiple time points. RESULTS: Horizontal deviations at the platform and apex and the angular deviation were significantly smaller in the FG group than the PG group (p < .05). Presurgical preparation and surgery times were significantly shorter in the FG group (p < .001). Patient satisfaction and willingness to receive repeat treatment were significantly better in the FG group than in the PG group (p < .005 and .025, respectively). Clinicians were more satisfied in the FG group than the PG group (p < .05). CONCLUSION: When placing an implant with sinus floor elevation, the flapless approach using a fully guided surgical system can be more accurate, faster, and increase the satisfaction of both the clinician and patient compared to the partially guided surgery.

Collaboration between otolaryngologists and oral surgeons in maxillary sinus elevation planning.

BACKGROUND: The collaboration between otolaryngologists and dental providers is crucial for the planning and execution of maxillary sinus elevation (MSE) procedures, which are integral to successful dental implant placements. PURPOSE: This article examines the essential role of otolaryngological assessments in identifying potential sinonasal risks that could impact the outcomes of MSE. MATERIALS AND METHODS: A comprehensive narrative review of existing literature was conducted. DISCUSSION: The review underscores the importance of thorough preoperative evaluations, including patient history, computed tomography (CT) or cone-beam CT (CBCT) scans, and nasal endoscopy, to mitigate sinonasal health risks. It details various clinical scenarios and patient assessments, emphasizing a systematic approach to diagnosing and managing sinonasal conditions proactively. The discussion reveals that while some sinus conditions may not significantly affect MSE success, conditions impacting mucociliary clearance and sinus drainage are critical risk factors requiring otolaryngological intervention. Additionally, the article introduces a grading system to assist clinicians in identifying patients who would benefit from otolaryngological evaluations prior to MSE. CONCLUSION: This review highlights the value of interdisciplinary collaboration and standardized protocols in enhancing the predictability and safety of MSE procedures, ultimately improving patient outcomes.

Bovine-originated xenografts versus synthetic bone grafting materials in lateral maxillary sinus floor augmentation: A systematic review and meta-analysis.

AIMS: This study aimed to systematically compare the patients undergoing lateral MSFA therapies utilizing bovine-originated xenografts versus varied synthetic bone grafting materials. METHODS: Pubmed, Scopus, Embase, and Cochrane Library were searched up to April 2023, compensated by a manual search in selected journals. Studies reporting histological outcomes (residual bone graft, newly formed bone, non-mineralized tissue) and clinical outcomes (implant survival, ISQ value) were included. Several analyses were performed, including meta-analysis, sensitivity study, and Egger's regression tests. RESULTS: Sixteen clinical/randomized control trials were included in this systematic review, among which 12 were enrolled in a meta-analysis. The percentage of newly formed bone within the grafted sinuses by hybrid HA/TCP was significantly higher than those by xenografts (WMD 2.85, 95%CI [0.72; 4.99]), but those grafted by pure HA (WMD -1.72, 95%CI [-3.15; -0.29]) or TCP (WMD -7.10, 95%CI [-13.02; -1.17]) were significantly lower than xenograft counterparts. The residual bone graft and non-mineralized tissue yielded by synthetic HA, TCP, and HA/TCP showed no significant differences with the xenograft group. CONCLUSION: The chemistry of grafted bone substitutes in lateral MSFA influenced the quantity of newly formed bone. Those grafted with hybrid HA/TCP yielded the highest amount of new bone compared to bovine-originated HA. However, this influence was not significant on residual bone graft and non-mineralized tissue.

Clinical evaluation of maxillary sinus floor elevation with or without bone grafts: a systematic review and meta-analysis of randomised controlled trials with trial sequential analysis.

Introduction: Our goal was to systematically review the current evidence comparing the relative effectiveness of two maxillary sinus floor elevation (MSFE) approaches (internal and external) without bone grafts with that of conventional/grafted MSFE in patients undergoing implantation in the posterior maxilla. Material and methods: Medical databases (PubMed/Medline, Embase, Web of Science, and Cochrane Library) were searched for randomised controlled trials published between January 1980 and May 2023. A manual search of implant-related journals was also performed. Studies published in English that reported the clinical outcomes of MSFE with or without bone material were included. The risk of bias was assessed using the Cochrane Handbook Risk Assessment Tool. Meta-analyses and trial sequence analyses were performed on the included trials. Meta-regression analysis was performed using pre-selected covariates to account for substantial heterogeneity. The certainty of evidence for clinical outcomes was assessed using GRADEpro GDT online (Guideline Development Tool). Results: Seventeen studies, including 547 sinuses and 696 implants, were pooled for the meta-analysis. The meta-analysis showed no statistically significant difference between MSFE without bone grafts and conventional MSFE in terms of the implant survival rate in the short term (n = 11, I2 = 0%, risk difference (RD): 0.03, 95% confidence intervals (CI): -0.01-0.07, p = 0.17, required information size (RIS) = 307). Although conventional MSFE had a higher endo-sinus bone gain (n = 13, I2 = 89%, weighted mean difference (WMD): -1.24, 95% CI: -1.91- -0.57, p = 0.0003, RIS = 461), this was not a determining factor in implant survival. No difference in perforation (n = 13, I2 = 0%, RD = 0.03, 95% CI: -0.02-0.09, p = 0.99, RIS = 223) and marginal bone loss (n = 4, I2 = 0%, WMD = 0.05, 95% CI: -0.14-0.23, p = 0.62, no RIS) was detected between the two groups using meta-analysis. The pooled results of the implant stability quotient between the two groups were not robust on sensitivity analysis. Because of the limited studies reporting on the visual analogue scale, surgical time, treatment costs, and bone density, qualitative analysis was conducted for these outcomes. Conclusions: This systematic review revealed that both non-graft and grafted MSFE had high implant survival rates. Owing to the moderate strength of the evidence and short-term follow-up, the results should be interpreted with caution.

Volume change after maxillary sinus floor elevation with apatite carbonate and octacalcium phosphate.

PURPOSE: Maxillary molars have low alveolar bone height diameter due to the presence of the maxillary sinus; thus, a sinus lift may be required in some cases. Changes in the volume of bone substitutes can affect the success of implant therapy. Therefore, this study aimed to compare the changes in the volume of two different bone substitutes-one based on carbonate apatite and the other on octacalcium phosphate-used in maxillary sinus floor elevation. METHODS: Nineteen patients and 20 sites requiring maxillary sinus floor elevation were included in the study. Digital Imaging and Communications in Medicine data for each patient obtained preoperatively and immediately and 6 months postoperatively were used to measure the volume of the bone grafting material using a three-dimensional image analysis software. The immediate postoperative volume of octacalcium phosphate was 95.3775 mm3 per piece of grafting material used. It was multiplied by the number of pieces used and converted to mL to determine the immediate postoperative volume. RESULTS: The mean resorption values of carbonate apatite and octacalcium phosphate were 12.7 ± 3.6% and 17.3 ± 3.9%, respectively. A significant difference in the amount of resorption of the two bone replacement materials was observed (P = 0.04). CONCLUSIONS: The results of this study indicate that both bone substitute materials tend to resorb. The two bone grafting materials that are currently medically approved in Japan have not been in the market for a long time, and their long-term prognosis has not yet been reported. Further clinical data are warranted.

The transalveolar approach with the small segmentation method for inclined maxillary sinus floor elevation: A retrospective study.

OBJECTIVE: To evaluate the clinical outcome of the transalveolar approach with the small segmentation method for inclined maxillary sinus floor elevation. METHODS: Sixty-one patients with an inclined maxillary sinus floor (tilt angle ≥ 10°) and insufficient residual bone height in the posterior maxilla were included and grouped according to the tilt angle of the sinus floor, with group A having patients with the tilt angle ≥ 10° and ≤ 30° and group B having patients with the tilt angle > 30°. After completing sinus membrane elevation and bone augmentation using bone substitute materials, the implants were inserted at the same appointment, and the restoration was completed after 5-6 months of osseointegration. The preoperative sinus floor level and sinus floor elevation achieved postoperatively were assessed and recorded. At pre- and post-operative timepoints, the sagittal plane of the cone beam computed tomography was used to evaluate the bone height changes at the peak, middle and valley points in the slope segment intended for implant implantation. RESULTS: Osseointegration was evident in all 61 patients, and the final restoration was completed with functional loading. After assessing the normality and homogeneity of variance, two-sample t-test or nonparametric tests were employed to estimate the differences in the bone height changes. The degrees of freedom (df) for this analysis were 59. The elevation attained at the middle point in groups A and B were 6.71 ± 1.38 and 5.75 ± 1.56 mm, respectively, demonstrating a significant difference (p < 0.05). Furthermore, at the peak and valley points, group A exhibited bone height changes of 5.79 ± 1.74 and 6.06 ± 1.45 mm, respectively, compared to group B with changes measuring 4.63 ± 2.18 and 5.58 ± 2.39 mm, respectively, with no significant difference in the two groups (p ≥ 0.05). The prevalence of intraoperative sinus membrane perforation was assessed using the chi-square test. It was found that four cases in group A and five cases in group B experienced sinus membrane perforation, with no significant difference in the two groups (p ≥ 0.05, df = 1). CONCLUSION: The transalveolar approach using the small segmentation method suggests a promising approach for elevating the inclined maxillary sinus floor.

Assessment of the osteogenic effect after maxillary sinus floor elevation and simultaneous implantation with or without bone grafts by analyzing trabecular bone parameters: a retrospective study

Abstract Objective: The aim of this population-based retrospective study was to compare the osteogenic effect of newly formed bone after maxillary sinus floor elevation (MSFE) and simultaneous implantation with or without bone grafts by quantitatively analyzing trabecular bone parameters. Methodology: A total of 100 patients with missing posterior maxillary teeth who required MSFE and implantation were included in this study. Patients were divided into two groups: the non-graft group (n=50) and the graft group (n=50). Radiographic parameters were measured using cone beam computed tomography (CBCT), and the quality of newly formed bone was analyzed by assessing trabecular bone parameters using CTAn (CTAnalyzer, SkyScan, Antwerp, Belgium) software. Results: In the selected regions of interest, the non-graft group showed greater bone volume/total volume (BV/TV), bone surface/total volume (BS/TV), trabecular number (Tb. N), and trabecular thickness (Tb. Th) than the graft group (p<0.001). The non-graft group showed lower trabecular separation (Tb. Sp) than the graft group (p<0.001). The incidence of perforation and bleeding was higher in the graft group than in the non-graft group (p<0.001), but infection did not significantly differ between groups (p>0.05). Compared to the graft group, the non-graft group showed lower postoperative bone height, gained bone height and apical bone height (p<0.001). Conclusion: MSFE with and without bone grafts can significantly improve bone formation. In MSFE, the use of bone grafts hinders the formation of good quality bone, whereas the absence of bone grafts can generate good bone quality and limited bone mass.

Crestal sinus augmentation in a head back position: Retrospective case series.

Objectives: To evaluate the clinical efficacy of Crestal Sinus Augmentation (CSA) in a head back position (CSA-HBP) for maxillary sinus mucosa elevation. Materials and Methods: We enrolled 209 patients, 246 maxillary sinuses, 348 sites in this study. Complications, maxillary sinus mucosal perforation rate and cumulative survival rate (CSR) data were collected to evaluate the clinical efficacy of CSA-HBP. Maxillary sinus mucosal elevation height (EH) and new bone height (NH) were measured by cone-beam computerized tomography and standard periapical radiographs. The implantation sites of residual bone height (RBH) ≤5 mm and RBH >5 mm were marked as Groups A (n = 81) and B (n = 267), respectively. The implantation sites of the second and third molar sites were marked as Group C (n = 134), and the remaining sites were marked as Group D (n = 214). Results: The RBH before implant placement was 6.63 ± 2.10 mm (95% confidence interval [CI] 6.41- 6.85 mm). The mucosal EH was 4.04 ± 1.86 mm (95% CI 3.85 - 4.24 mm). The NH was 2.36 ± 1.20 mm (95% CI 3.85-4.24 mm). No other complications were found except three cases of postoperative swelling and one case of nasal blood secretions. The overall mucosal perforation rate was 1.44% (5/348, 95% CI 0.2%-2.7%) and the rate of RBH ≤ 5 mm (Group A) was 1.49% (2/134, 95% CI 0%-3.50%). The 8-year CSR was 99.71% (347/348, 95% CI 99.2%-100.0%). Mucosal EH and NH were higher in RBH ≤5 mm (Group A) than in RBH >5 mm (Group B) (P = 0.001 and P = 0.001, Mann-Whitney U-test). There were no significant differences in mucosal EH and perforation rate between second and third molar sites (Group C) and other sites (Group D) (P = 0.77, Mann-Whitney U-test, and P = 0.16, Yates' Chi-square independence test). Conclusions: CSA-HBP is a minimally invasive and reliable technique.

Rehabilitation of distal extension maxillary ridges with fixed and removable implant-supported prostheses: Preliminary 12-month randomized clinical trial.

PURPOSE: This trial evaluated clinical outcomes of fixed and removable implant-supported prostheses for rehabilitation of atrophied distal extension maxillary ridges. MATERIALS AND METHODS: A total of 54 participants with atrophied distal extension maxillary ridges were randomly assigned into three groups (n = 18/group). Group I (SLF); participants treated with fixed restoration supported by three long implants after sinus augmentation, Group II (SF); participants treated with fixed restoration supported by one long and two short implants, and Group III (OD): participants treated with removable partial denture assisted by one long implant that was placed mesial to maxillary sinus (IARPD). Modified plaque index (MPI), modified gingival index (MGI), pocket depth (PD), implant stability (IS), and crestal bone loss (CBL) were measured after prosthesis insertion (T0), 6 (T6), and 12 months (T12) after insertion. Patient satisfaction was measured at T12 using a visual analog scale (VAS). RESULTS: The implant survival rates were 96.8%, 92.4%, and 84.6% for SLF, SF, and OD groups respectively. The SLF recorded the highest MPI, MGI, PD, and IS values, followed by the SF, and the OD showed the lowest values. The OD recorded the highest CBL followed by the SF and the SLF showed the lowest CBL. With exception of satisfaction with surgery and cleaning, SLF and SF groups recorded significantly higher patient satisfaction than the OD for all VAS questions. CONCLUSION: Fixed restorations supported with either long or short implants were associated with improved implant stability, reduced bone loss, and increased patient satisfaction compared to implant-assisted RPDs. However, implant-assisted RPDs were associated with more favorable peri-implant soft tissue health and increased satisfaction with surgery, healing, and cleaning.

The Radiological Evaluation of the Anatomy of the Alveolar Antral Artery and the Lateral Wall Thickness Using Cone-Beam Computed Tomography: A Retrospective Study.

The objectives study aims to assess the position and route of the alveolar antral artery and the lateral wall thickness of the maxillary sinus using cone-beam computed tomography (CBCT), reducing the risk of complications and improving the success rate of surgery. MATERIALS AND METHODS: This study included CBCT scans from 238 patients. The detection diameter of AAA and distance of the lower border of AAA to the maxillary sinus floor at the first premolar, second premolar, first molar, and second molar locations were evaluated. The route of AAA was observed with novel classification. Furthermore, the distance from the maxillary sinus floor to the alveolar crest at four posterior tooth locations was measured respectively. Moreover, the lateral wall thickness at four locations was assessed. Data were subjected to statistical analysis. RESULTS: AAA was observed in 62.18% of all sinuses. The mean diameter was 0.99±0.21 mm, with significant differences within gender. Half of the route of AAA was intrasinus intraosseous type. The mean distance between the maxillary sinus floor and AAA was 8.00±2.68 mm, with a significant difference between dentate and edentulous status at the first molar location. Distance from the sinus floor to the alveolar ridge crest in edentulous status negatively correlated with the distance from the sinus floor to AAA at the first molar location. The mean thickness of the lateral wall was 2.03±0.91 mm, and the difference in thickness between males and females at the four locations was statistically significant. CONCLUSION: intrasinus-intraosseous type, is the most common route. Special care should be taken at the first molar location during a lateral window sinus floor elevation. CBCT is highly recommended to before lateral wall maxillary sinus floor elevation.

Bone vitality and vascularization of mandibular and maxillary bone grafts in maxillary sinus floor elevation: A retrospective cohort study.

OBJECTIVES: Mandibular retromolar (predominantly cortical) and maxillary tuberosity (predominantly cancellous) bone grafts are used in patients undergoing maxillary sinus floor elevation (MSFE) for dental implant placement. The aim of this retrospective cohort study was to investigate whether differences exist in bone formation and vascularization after grafting with either bone source in patients undergoing MSFE. METHODS: Fifteen patients undergoing MSFE were treated with retromolar (n = 9) or tuberosity (n = 6) bone grafts. Biopsies were taken 4 months postoperatively prior to dental implant placement, and histomorphometrically analyzed to quantify bone and osteoid area, number of total, apoptotic, and receptor activator of nuclear factor-κB ligand (RANKL)-positive osteocytes, small and large-sized blood vessels, and osteoclasts. The grafted area was divided in three regions (caudal-cranial): RI, RII, and RIII. RESULTS: Bone volume was 40% (RII, RIII) higher and osteoid volume 10% (RII) lower in retromolar compared to tuberosity-grafted areas. Total osteocyte number and number of RANKL-positive osteocytes were 23% (RII) and 90% (RI, RII) lower, but osteoclast number was higher (retromolar: 12, tuberosity: 0) in retromolar-grafted areas. The total number of blood vessels was 80% (RI) to 60% (RIII) lower, while the percentage of large-sized blood vessels was 86% (RI) to 25% (RIII) higher in retromolar-grafted areas. Number of osteocyte lacunae and apoptotic osteocytes were similar in both bone grafts used. CONCLUSIONS: Compared to the retromolar bone, tuberosity bone showed increased bone vitality and vascularization in patients undergoing MSFE, likely due to faster bone remodeling or earlier start of new bone formation. Therefore, tuberosity bone grafts might perform better in enhancing bone regeneration.

Bone-Regenerative Ability of Platelet-Rich Plasma Following Sinus Augmentation with Anorganic Bovine Bone: A Systematic Review with Meta-Analysis.

BACKGROUND: The objective of this systematic review is to assess the effect of the adjuvant use of platelet-rich plasma (PRP) and its type on new bone formation by anorganic bovine bone during maxillary sinus floor augmentation procedure. METHODS: PubMed, Cochrane Central Register of Controlled Trials, and Ovid databases were searched for relevant studies published up to 16 September 2021. Randomized clinical trials (RCTs) and non-randomized controlled clinical trials (CCTs) that reported data on the new bone formation (measured by histomorphometric analysis) were considered. Risk of bias and quality assessment of included studies were evaluated following the Cochrane Handbook for Systematic Reviews of Interventions and the Risk Of Bias In Non-randomised Studies of Interventions (ROBINS-I) tool. Strength of evidence was assessed following the approach of the Agency for Healthcare Research and Quality (AHRQ) through its evidence-based practice center (AHRQ EPC). The meta-analysis was based on the primary outcome of newly formed bone, for which the standard mean difference was calculated. RESULTS: After the application of eligibility criteria, six clinical trials (three RCTs and three CCTs) covering 85 maxillary sinus floor elevation procedures were included. The pooled new bone formation value for PRP was 1.67 (95% CI: -0.15 to 3.49; I2: 86%), indicating the absence of significant effect. Plasma rich in growth factors (PRGF) was the pure PRP tested in five of the included studies. When sub-group (type of PRP) meta-analysis was performed, significantly higher new bone formation was observed in the PRGF group [2.85 (95% CI: 0.07 to 5.64; I2: 88%)] in comparison to the control group. CONCLUSIONS: A beneficial effect on new bone formation after maxillary sinus floor elevation can be obtained when anorganic bovine bone is mixed with PRGF.

Evaluation of volume changes following lateral window maxillary sinus floor elevation using Minics software.

Background: Significant volume changes at the site of lateral window maxillary sinus floor elevation have been reported 6 months postoperatively, with stabilization thereafter. However, at present, there is no consensus regarding the gold standard to assess the shape and volume of the bone graft site after implantation. This study aimed to analyze volume changes in the lateral window maxillary sinus floor elevation region using Minics software. Methods: We analyzed 40 patients who underwent lateral window maxillary sinus floor elevation surgery at the Stomatology Department of Binhaiwan Central Hospital, Dongguan, China between 2017 and 2020. Twenty patients underwent lateral window maxillary sinus floor elevation with simultaneous implantation, while 20 patients underwent lateral window maxillary sinus floor elevation with delayed implantation 6 months later. Minics software was used for three-dimensional analysis of the elevation site on the day after surgery (T1) and 6 months after surgery (T2) in both groups. Results: The elevation site volume was reduced 6 months after lateral window maxillary sinus floor elevation. The differences in the length, width, height from the tip, and volume of the implant between T1 and T2 were statistically significant. Conclusions: The length, width, height, and volume of the lateral window maxillary sinus floor elevation region were reduced using Minics software, suggesting that the volume of the elevation site should be enlarged as much as possible during the operation to prevent volume shrinkage.

Radiographic assessment of deproteinized bovine bone mineral (DBBM) and collagen-stabilized DBBM for transalveolar sinus floor elevation: A 2-year retrospective cohort study.

BACKGROUND: Theoretically, collagen-stabilized deproteinized bovine bone mineral (DBBM-C) has better operability compared with DBBM. DBBM-C avoids dispersing during the transalveolar sinus floor elevation (TSFE) because of its block shape. PURPOSE: To evaluate radiological changes of using DBBM-C in TSFE. MATERIALS AND METHODS: Patients who received TSFE using DBBM (Bio-Oss®) or DBBM-C (Bio-Oss® collagen) with simultaneous implantation were recruited. Graft bone height apically (aGH), endo-sinus bone gain (ESBG), and crest bone level (CBL) were assessed through panoramic radiograph and cone beam computed tomography (CBCT). RESULTS: A total of 138 patients (138 implants) were retrospectively enrolled. After 2 years of implantation, the incidence of postoperative complications was 4.2% (95% CI: 0.9%-11.7%) and 4.5% (95% CI: 0.9%-12.7%) for DBBM and DBBM-C groups, respectively. Measured in panoramic radiograph, ΔaGH of DBBM-C (1.8 mm, SD: 1.4, 95% CI: 1.2-2.4, P = 0.044) group was significantly higher than that of DBBM (1.2 mm, SD: 1.4, 95% CI: 0.7-1.7) after 24 months. No significant differences for ΔCBL were noted during the entire observation period. Measured through CBCT, ESBG was 5.0 (SD: 1.8, 95% CI: 4.1-5.8) mm in DBBM group and 4.6 (SD: 1.6, 95% CI: 3.9-5.3) mm in DBBM-C group 24 months after implantation. The aGH value of DBBM-C group was significantly higher compared with DBBM in CBCT (OR = 1.4, 95% CI: 1.1-1.9, P = 0.020). CONCLUSIONS: DBBM-C could achieve similar bone generation as DBBM in TSFE. Both materials could maintain aGH, ESBG, and CBL relatively stable 2 years after implantation.

Endoscope-controlled maxillary sinus floor elevation: a review of the literature.

A systematic review of the literature was conducted to assess the safety and efficacy of endoscope-assisted maxillary sinus elevation. PubMed, Embase, Web of Science, and the Cochrane database were searched for articles in English. Published studies involving patients who had undergone endoscope-assisted maxillary sinus floor augmentation were selected. The validity of the included articles was evaluated. After going through full texts, a total of 12 studies met the eligibility criteria and were included. It was concluded that endoscope-controlled maxillary sinus floor elevation was a viable and beneficial method, providing direct visualisation of the integrity of the mucosa and placing of bone graft material. The endoscope could be inserted into the maxillary sinus lumen, subantral space below the Schneiderian membrane, or through the alveolar crest. With the endoscope, perforations can be detected and managed precisely. However, high-quality clinical trials are still needed to validate the predictability and advantages of this surgical procedure.

Morphometric and histomorphometric evaluations of high-purity macro/microporous beta-tricalcium phosphate in maxillary sinus floor elevation: preliminary results on a retrospective, multi-center, observational study.

BACKGROUND: The present study examined the effectiveness of high-purity macro/microporous beta-tricalcium phosphate (HPMM ß-TCP) as a bone grafting material for maxillary sinus floor elevation by morphometric, histopathological, and histomorphometric evaluations. METHODS: Ten unilateral maxillary sinus floor elevation procedures using 100% HPMM ß-TCP were performed in 10 patients. Morphometric evaluation was carried out by computed tomography (CT) imaging immediately after augmentation and prior to dental implant placement 7 months later. Histopathological and histomorphometric evaluations were carried out by bone biopsy retrieval at the time of dental implant placement 7 months after sinus floor elevation. RESULTS: All 10 sinus floor elevations were successful. Morphometric evaluation by CT showed that the vertical height and volume gained by sinus floor elevation decreased 7 months after surgery. Histopathological evaluation of bone biopsy retrieval specimens showed no signs of inflammation at the newly formed bone area and the native alveolar bone area. New bone formation was observed at the cranial side from the native alveolar bone. The newly formed bone had a trabecular structure and was in intimate contact with the HPMM ß-TCP material. Histomorphometric evaluation of bone biopsy retrieval specimens showed an average new bone volume of 33.97% ± 2.79% and an average residual HPMM ß-TCP volume of 15.81% ± 4.52%. CONCLUSIONS: In this study, HPMM ß-TCP showed osteoconductive properties for vertical augmentation of the atrophied maxilla by means of a maxillary sinus floor elevation procedure allowing subsequent dental implant placement after a 7-month healing period.

Management of Schneiderian membrane perforations during maxillary sinus floor augmentation with lateral approach in relation to subsequent implant survival rates: a systematic review and meta-analysis.

BACKGROUND: This systematic review aimed to propose a treatment protocol for repairing intraoperative perforation of the Schneiderian membrane during maxillary sinus floor augmentation (MSFA) procedures with lateral window technique. In turn, to assess subsequent implant survival rates placed below repaired membranes compared with intact membranes and therefore determine whether membrane perforation constitutes a risk factor for implant survival. MATERIAL AND METHODS: This review was conducted according to PRISMA guidelines. Two independent reviewers conducted an electronic search for articles published between 2008 and April 30, 2020, in four databases: (1) The National Library of Medicine (MEDLINE/PubMed) via Ovid; (2) Web of Science (WOS); (3) SCOPUS; and (4) Cochrane Central Register of Controlled Trials (CENTRAL); also, a complementary handsearch was carried out. The Newcastle-Ottawa Quality Assessment Scale was used to assess the quality of evidence in the studies reviewed. RESULTS: Seven articles fulfilled the inclusion criteria and were analyzed. A total of 1598 sinus lift surgeries were included, allowing the placement of 3604 implants. A total of 1115 implants were placed under previously perforated and repaired membranes, obtaining a survival rate of 97.68%, while 2495 implants were placed below sinus membranes that were not damaged during surgery, obtaining a survival rate of 98.88%. The rate of Schneiderian membrane perforation shown in the systematic review was 30.6%. In the articles reviewed, the most widely used technique for repairing perforated membranes was collagen membrane repair. CONCLUSIONS: Schneiderian membrane perforation during MFSA procedures with lateral approach is not a risk factor for dental implant survival (p=0.229; RR 0.977; 95% CI 0.941-1.015). The knowledge of the exact size of the membrane perforation is essential for deciding on the right treatment plan.