Maxillary Sinus Floor Augmentation With Synthetic Bone Substitutes Compared With Other Grafting Materials: A Systematic Review and Meta-analysis

Insights into Sinus-Lift Bone Grafting Materials: What's Changed?

BACKGROUND

Sinus-lift (SL) is a pre-prosthetic procedure with the objective of increasing bone height to achieve implant insertion primary stability in implant-supported prostheses. The biomechanical properties of SL augmentation materials are influenced by their origin, manufacture, bioactive substances addition, receiver, and surgical procedure. This systematic review provides insights into state-of-the-art SL biomaterials, focusing on autologous bone grafting as the gold standard.

METHODS

The study followed the PRISMA flow diagram, searching WoS (Web of Science), Embase, Cochrane, and PubMed databases using the search terms «sinus lift» OR «sinus augmentation» OR «bone graft» OR «bovine» OR «porcine» OR «autologous» OR «allogenic» OR «xenogeneic» OR «alloplastic» OR «hydroxyapatite» OR «β-tricalcium phosphate (β-TCP)» OR «equine» OR «PRF».

RESULTS

The highest bone gain was provided by Bioglass at 42%. Articles written between 2014 and 2024 in English or French, containing human studies and with full text available, were included. Participants were required to be in good general health, without acute, chronic, or congenital diseases, or substance abuse (drugs, alcohol, or nicotine). SL surgery was performed using the lateral approach, with no Schneiderian membrane perforation or postoperative complications. The network meta-analysis was conducted using the R statistical computing environment. To assess the inconsistency between direct and indirect evidence, we used a net heat plot. To evaluate heterogeneity across studies, we used the chi-squared-based Q-test and I2 statistic. A significance level of 0.05 was applied throughout all analyses.

RESULTS

Allogeneic bovine bone and hydrox yapatite demonstrated the lowest resorption rates. Significant differences were found for residual graft and connective tissue between allogenous bovine bone (ABB) + AlB vs. β-TCP + PRF (p = 0.028); ABB + AlB vs. β-TCP (p = 0.034); ABB + AlB vs. BCP (p = 0.037). Meta-analysis showed that the overall heterogeneity was 51.8% (6.9-75%; p = 0.019), with significant heterogeneity within designs (p = 0.007) and no significant heterogeneity between designs (p = 0.39). AB had a better bone regeneration ratio compared to many of the other interventions, but only two passed the threshold of significance: A1B and B-TCP + AB.

CONCLUSIONS

A grafting material's superiority is determined by its new bone formation ratio, connective tissue integration, residual graft content, and bone resorptionratio. Although autologous bone grafting has exhibited superior bone regeneration compared to other biomaterials, it was not favored due to its unpredictable connective tissue concentration and bone resorption ratio. Additionally, autologous bone exhibited the fastest metabolic turnover among all grafting materials.

Histomorphometric outcome following sinus floor augmentation with allogeneic adipose tissue-derived stem cells. A randomized controlled experimental study

The aim of this pre-clinical study was to test the hypothesis of no difference in histomorphometric outcome following sinus floor augmentation (SFA) with allogeneic adipose tissue-derived stem cells (AASCs) seeded on deproteinized bovine bone mineral (DBBM) (test) compared with excipient on DBBM (control). Eighteen minipigs were allocated into three groups of six animals and euthanised after one month (T1), two months (T2), and four months (T3). The sinuses of each animal were randomly assigned to either test or control with identical graft volume. Percentage of newly formed bone (NFB), non-mineralized tissue, residual DBBM, and bone-to-implant contact (BIC) were estimated by histomorphometric analysis in a randomly selected region of interest and summarized as mean percentage with 95% confidence interval. Test group, mean percentage of NFB and BIC was 8.8 and 19.5 (T1), 17.7 and 23.2 (T2), 37.1 and 30.4 (T3). Control group, corresponding values were 8.9 and 13.9 (T1), 18.7 and 23.3 (T2), 36.8 and 36.6 (T3). There were no significant differences in NFB or BIC at T1 (P = 0.964; 0.551), T2 (P = 0.927; 0.992), and T3 (P = 0.971; 0.557) between test or control. Percentage of NFB was significantly higher at T3 compared with T1, in test (P = 0.001) and control (P = 0.004), while no significant difference in BIC was disclosed between T1, T2, and T3, in test and control, respectively. In conclusion, adding AASCs to DBBM seem not to improve NFB or BIC compared with DBBM alone in conjunction with SFA.

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.

Additive Manufacturing Titanium Dental Implants Placed in Sinuses Grafted with 70HA:30-TCP: A One-Year Retrospective Study for Evaluation of Survival Rate

The present short-term retrospective study evaluated the implant survival rate and peri-implant bone loss around additive-manufactured titanium implants placed in sinuses grafted with Plenum Osshp (Plenum Bioengenharia, Jundia, SP, Brazil) (70HA:30β-TCP) material. A total of 39 implants were inserted after 23 sinus floor elevation procedures in 16 consecutive patients. Prosthetic rehabilitation included fixed partial prostheses (three units), single crowns (eleven units), and fixed full arches (three units). Clinical and radiographic parameters of implant-supported restorations were evaluated after at least one year of occlusal loading. The implant-crown success criteria included the absence of pain, suppuration, and clinical mobility, an average distance between the implant shoulder and the first visible bone contact (DIB) < 1.0 mm from the initial surgery, and the absence of prosthetic complications at the implant-abutment interface. The overall cumulative implant survival rate was 97.43%. No prosthetic complications at the implant-abutment interface were reported. After one year, the mean DIB was 0.23 mm ± 0.14. Within the limits of this retrospective study, it can be concluded that 70 HA:30 β-TCP allowed stable and reliable bone support to maintain healthy conditions around titanium dental implants produced by additive manufacturing.

Maxillary sinus floor augmentation with autogenous bone graft compared with composite grafts: A one-year single-blinded randomized controlled trial

OBJECTIVE

The objective was to assess the one year implant treatment outcome and patient-related outcome measures (PROMs) following maxillary sinus floor augmentation (MSFA) with autogenous bone graft (ABG) from the zygomatic buttress (control) compared with 1:1 mixture of ABG and anorganic porcine bone mineral (APBM) (Test I) or biphasic bone graft material (BBGM) (Test II).

MATERIALS AND METHODS

Sixty healthy patients (34 females, 26 males) were randomly allocated to either control or test groups. Outcome measures included survival of suprastructures and implants, implant stability quotient, health status of peri-implant tissue, peri-implant marginal bone loss, frequency of complications, and PROMs using Oral Health Impact Profile-14 combined with questionnaire assessing patient perception of peri-implant soft tissue, prosthetic solution, implant function, and implant treatment outcome using visual analogue scale. Mean differences were expressed with standard deviation and 95% confidence interval. Level of significance was .05.

RESULTS

All suprastructures and implants were well-functioning after one year of functional implant loading. There was no significant difference between control and test groups in any of the applied outcome measures. The implant stability significantly increased from implant placement to abutment connection within all groups (p < .001). High patient satisfaction and significant improvement in oral health-related quality of life was also reported within all groups.

CONCLUSION

This study demonstrates that MSFA with composite grafts containing minimal amounts of ABG reveals comparable implant treatment outcomes as compared with ABG alone, after one year of functional implant loading. Extensive ABG harvesting in conjunction with MSFA therefore seems not to be needed.

Implant stability and clinical outcome between implant placement using internal sinus floor elevation with alloplastic bone material grafting and without grafting: A 1-year randomized clinical trial

OBJECTIVE

To compare implant stability and clinical outcome in implant placement between osteotome sinus floor elevation (OSFE) with biphasic calcium phosphate (BCP) which consisted of 30% of hydroxyapatite (HA) and 70% of beta-tricalcium phosphate (β -TCP) grafting material and OSFE without using bone grafting material. The research questions is whether the BCP provides any benefit in OSFE or not.

MATERIALS AND METHODS

Thirty patients (30 implants) with a single edentulous area of upper premolar or molar were randomly separated into OSFE with BCP (n = 15) and OSFE without grafting (n = 15). The patients were reevaluated 3, 6, 9, and 12 months after implant loading. The clinical assessments (implant stability quotient (ISQ), implant survival-failure rate, and surgical complication) were analyzed. Together with radiographic assessments in 2D (endo-sinus bone gain (ESBG), mean marginal bone change (MMBC)) and 3D (endo-sinus bone gain in CBCT (ESBG-CT)) were evaluated, with a mean follow-up time of at least 12 months of functional loading and prosthetic complication.

RESULTS

20 remaining implants (OSFE with BCP, n = 10; OSFE without grafting, n = 10) were analyzed. Mean ISQ was 79.18 ± 3.43 in 1-year follow-up (ISQ; OSFE with BCP = 78.72 ± 3.46, OSFE without grafting = 79.65 ± 3.52). ISQ in both groups increased steadily without significant differences in each follow-up. (p = 0.56). In radiographic evaluation, at 6-, 9-, and 12-month, OSFE without grafting group showed statistically significant lower MMBC (p < 0.05). The 1-year clinical results showed that 2 implants failed in OSFE with BCP, and 1 implant failed in OSFE without grafting.

CONCLUSIONS

Graft material "BCP" (HA30:TCP70) coupled with OSFE presents no extraordinary benefit in implant stability, clinical and radiographic outcome in 1-year follow-up.

CLINICAL RELEVANCE

Clinically, OSFE with grafting materials provides no additional benefit.

CLINICAL TRIAL REGISTRATION NUMBER

TCTR20210517008 (date of registration: May 17, 2021).

Maxillary Sinus Floor Augmentation With Allograft Alone Compared With Alternate Grafting Materials: A Systematic Review and Meta-Analysis

A meta-analysis of scientific literature was conducted to ascertain the superiority between allografts and other regenerative grafts for maxillary sinus floor augmentation (MSFA). Review was performed following Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines and registered in PROSPERO-CRD42023392766. Electronic databases like PubMed, Google scholar and Ebsco Host were searched from 2000 to December 2022 for studies reporting MSFA using allografts or other regenerative grafts. Quality assessment of included studies was evaluated using the Cochrane risk of bias (ROB)-2 tool for randomized controlled trials through its domains. Risk of bias summary graph and ROB summary applicability concern were plotted using RevMan software version 5.3. The standardized mean difference was used as a summary statistic measure with random effect model and P value <0.05 as statistically significant. Four studies fulfilled the eligibility criteria and were included in qualitative synthesis, of which all 4 studies were suitable for meta-analysis. Pooled estimate through standardized mean difference signifies that new bone formation was more or less similar for both graft materials, whereas regenerative grafts showed more residual bone grafts ( P >0.05). Publication bias through funnel plot showed symmetric distribution with the absence of systematic heterogeneity. Both allografts and other regenerative grafts are equally effective in the MSFA in terms of new bone formation, whereras regenerative grafts showed more residual bone grafts. Furthermore, randomized controlled trials are required to establish evidence in outcomes involving sinus floor augmentation and different graft materials.

Osseodensification versus lateral window technique for sinus floor elevation with simultaneous implant placement: A randomized clinical trial on patient-reported outcome measures

OBJECTIVES

To compare patient-reported outcome measures and additional surgical outcomes after sinus floor elevation (SFE) with osseodensification (OD) versus lateral window (LW), both with simultaneous implant placement.

MATERIALS AND METHODS

Twenty participants requiring single-implant rehabilitation with residual bone height (RBH) ≤4 mm were enrolled. Pain experience, quality of life (QoL) via the Oral Health Impact Profile-14 (OHIP-14), analgesics intake, and other symptoms were self-reported for a week on a daily basis. Surgery duration, complications, and implant stability quotient at baseline (ISQ T0 ) and after 6 months (ISQ T6 ) were registered. Participants were followed up for 1 year.

RESULTS

From Day 0 (day of surgery) to Day 3, pain experience was significantly lower (p < 0.05) in the OD group. OHIP-14 score was significantly lower (p < 0.05) in the OD group on all postoperative days, except on Day 5. Average analgesics intake was significantly lower (p < 0.001) in the OD group. Surgery mean duration was significantly higher (p < 0.001) in LW compared to OD (71.1 ± 10.4 vs. 32.9 ± 5.3 min). After osseointegration period, all implants were successfully restored with screw-retained crowns.

CONCLUSIONS

Within the limitations of this study, it can be concluded that OD and LW techniques were similarly effective in SFE with simultaneous implant placement when RBH ≤ 4 mm. However, OD significantly outperformed LW in pain experience, impact on self-perceived QoL, surgery duration, postoperative edema, and analgesics intake.

Maxillary sinus membrane elevation and coagulum compared with maxillary sinus floor augmentation and a composite graft: A 1-year single-blinded randomized controlled trial

OBJECTIVE

The aim was to evaluate the 1-year implant outcome and patient-related outcome measures (PROMs) after maxillary sinus membrane elevation and coagulum (test) compared with maxillary sinus floor augmentation and a 1:1 ratio of autogenous bone graft from the buccal antrostomy and deproteinised porcine bone mineral (DPBM) (control).

MATERIALS AND METHODS

Forty patients (30 female, 10 male) with a mean age of 50 years (range 25-71 years) and an alveolar ridge height between 4 and 7 mm were randomly allocated to test or control. Outcome measures included survival of suprastructures and implants, implant stability quotient, health status of the peri-implant tissue, peri-implant marginal bone loss, frequency of complications and PROMs using Oral Health Impact Profile-14 combined with questionnaires assessing patient's perception of the peri-implant soft tissue, implant crown, function of the implant, and total implant treatment outcome using visual analogue scale. Mean differences were expressed with standard deviation and 95% confidence interval. Level of significance was 0.05.

RESULTS

All suprastructures and implants were well-functioning after 1-year of functional implant loading. No significant difference in any of the applied outcome measures was observed between test and control. Both treatments revealed high patient satisfaction scores and significant improvement in oral health-related quality of life.

CONCLUSION

There were no significant differences in implant outcome and PROMs between test and control, after 1-year of functional implant loading. Neither of the treatments can therefore be considered better than the other. Thus, long-term randomized controlled trials are needed before definitive conclusions can be provided about the two treatment modalities.

The impact of deproteinized bovine bone particle size on histological outcomes in sinus floor elevation: a systematic review and meta-analysis

OBJECTIVES

The main purpose of this study was to evaluate whether large granular bovine bone can be as effective as small granular bovine bone in maxillary sinus floor elevation.

METHODS

A comprehensive online search of eligible articles was conducted using PubMed, EMBASE, Cochrane Library, Scopus, and Web of Science, and a systematic review and meta-analysis was performed from establishment to February, 2023. The outcome indicators were the percentage of connective tissue, the percentage of newly formed bone and the percentage of residual xenograft respectively. The meta-analysis was conducted by using the Stata 15.1 (Stata Conpernarn, USA) and Review Manager software5.4.1.

RESULTS

After careful screening and review, a total of 4 studies were included for systematic review and meta-analysis. The data were extracted to compare the histological performance of bovine bones with different particle sizes after maxillary sinus elevation. No significant differences were found in the percentage of connective tissue, the percentage of newly formed bone, and the percentage of residual xenograft.

CONCLUSION

In this study, a systematically review of the previous literature showed that similar histological results were obtained for both large-particle bovine bone and small-particle bovine bone. Therefore, the large granular bovine bone and the small granular bovine bone were equally effective in maxillary sinus elevation. It is difficult to make conclusion from limited evidence from four studies. More clinical evidence was needed.

The Effectiveness and Practicality of a Novel Barrier Membrane for the Open Window in Maxillary Sinus Augmentation with a Lateral Approach, with Risk Indicators for Bone Graft Displacement and Bone Height Decrease: A Prospective Study in Humans

Maxillary sinus augmentation with a lateral approach (MSA) is a well-established treatment. In this prospective study, we evaluated risk factors for postoperative bone graft displacement and reported the clinical application of long-term resorbable L-lactic acid/-caprolactone (PLA/PCL) as a barrier membrane to cover the open window in the lateral wall in MSA. Twenty-four patients underwent MSA according to the relevant criteria; CT data obtained before and 1 week (1 w) and 5-6 months (5 m) post-MSA, bone height changes, bone height reduction rates at 1 w and 5 m post-MSA, bone graft displacement measurements, and risk factors were examined. All patients showed bone height increments (p < 0.005). However, no difference was observed between 1 w and 5 m post-MSA. Bone graft displacement was observed in eight patients; the reduction rate from 1 w to 5 m post-MSA was 8.38% ± 4.88%. Sex, septa, maxillary sinus floor-palatal bone distance, and maxillary sinus floor-maxillary ostium distance were associated with bone graft displacement (p < 0.05). The height from the maxillary sinus floor to the palatal bone and the sinus angle influenced the augmentation degree (p < 0.05). The PLA/PCL membrane is compared favorably with other membranes and may be useful as a barrier membrane for the MSA open window.

Bone grafting techniques and materials for implant dentistry

Bone quality, volume, height and width all play a pivotal role in dental implant stability, success and survival. A lack of adequate bone can be overcome with various bone grafting procedures. Dependent on many factors, including the amount of bone required, the site of implant placement, patient preferences and clinician factors; the type of bone grafting material and procedure undertaken can vary. Supplemental bone can be sourced from a variety of sources, including autogenous, allogenous and xenograft bone. Dependent on the source of the bone, it will have different properties in aiding bone formation, as well as being presented in different formulations, such as bone particles or bone blocks.The aim of this paper is to provide an overview of bone grafting indications, materials and types of bone grafting techniques that can be utilised to aid dental implant provision. It also discusses the properties needed to ensure optimal success of guided bone regeneration techniques.

Effect of the implant apical exposure and coverage < or ≥ 2 mm bone graft on transcrestal sinus floor elevation: a 1- to 7-year retrospective cohort study

OBJECTIVES

This study aimed to analyze the effect of the apex coverage by the bone graft, including exposure and coverage less than or greater than 2 mm on implant survival rate and peri-implant bone and soft tissue remodeling.

MATERIALS AND METHODS

A total of 264 implants in 180 patients who had undergone transcrestal sinus floor elevation (TSFE) with simultaneous implant placement were included in this retrospective cohort study. Radiographic assessment was used to categorize the implants into three groups based on apical implant bone height (ABH): ≤ 0 mm, < 2 mm, or ≥ 2 mm. The implant survival rate, peri-implant marginal bone loss (MBL) during short-term (1-3 years) and mid- to long-term (4-7 years) follow-up, and clinical parameters were used to evaluate the effect of implant apex coverage after TSFE.

RESULTS

Group 1 had 56 implants (ABH ≤ 0 mm), group 2 had 123 implants (ABH > 0 mm, but < 2 mm), and group 3 had 85 implants (ABH ≥ 2 mm). There was no significant difference in the implant survival rate between groups 2 and 3 compared to group 1 (p = 0.646, p = 0.824, respectively). The MBL during short-term and mid- to long-term follow-up indicated that apex coverage could not be considered a risk factor. Furthermore, apex coverage did not have a significant effect on other clinical parameters.

CONCLUSIONS

Despite limitations, our study found that implant apex coverage by the bone graft, including exposure and coverage levels less than or greater than 2 mm, did not significantly affect implant survival, short-term or mid- to long-term MBL, or peri-implant soft tissue outcomes.

CLINICAL RELEVANCE

Based on 1- to 7-year data, the study suggests that implant apical exposure and coverage levels of less than or greater than 2 mm bone graft are both valid options for TSFE cases.

Osteoinductive calcium phosphate with submicron topography as bone graft substitute for maxillary sinus floor augmentation: A translational study

OBJECTIVES

The aim of this study was the preclinical and clinical evaluation of osteoinductive calcium phosphate with submicron surface topography as a bone graft substitute for maxillary sinus floor augmentation (MSFA).

MATERIAL AND METHODS

A preclinical sheep model of MSFA was used to compare a calcium phosphate with submicron needle-shaped topography (BCPN , MagnetOs Granules, Kuros Biosciences BV) to a calcium phosphate with submicron grain-shaped topography (BCPG ) and autologous bone graft (ABG) as controls. Secondly, a 10-patient, prospective, randomized, controlled trial was performed to compare BCPN to ABG in MSFA with two-stage implant placement.

RESULTS

The pre-clinical study demonstrated that both BCPN and BCPG were highly biocompatible, supported bony ingrowth with direct bone apposition against the material, and exhibited bone formation as early as 3 weeks post-implantation. However, BCPN demonstrated significantly more bone formation than BCPG at the study endpoint of 12 weeks. Only BCPN reached an equivalent amount of bone formation in the available space and a greater proportion of calcified material (bone + graft material) in the maxillary sinus compared to the "gold standard" ABG after 12 weeks. These results were validated in a small prospective clinical study, in which BCPN was found comparable to ABG in implant stability, bone height, new bone formation in trephine core biopsies, and overall clinical outcome.

CONCLUSION

This translational work demonstrates that osteoinductive calcium phosphates are promising bone graft substitutes for MSFA, whereas their bone-forming potential depends on the design of their surface features. Netherlands Trial Register, NL6436.

A Randomized Clinical Trial Comparing Implants Placed in Two Different Biomaterials Used for Maxillary Sinus Augmentation

The objective of this study was to compare marginal bone loss, surgical and clinical complications, and dental implant survival rate in bilateral maxillary sinus augmented by autologous or porcine xenograft. A randomized controlled clinical trial using split-mouth design enrolled 12 consent adult patients (59.7 ± 8.7 years), who received bilateral maxillary sinus floor augmentation for oral rehabilitation with implant-supported prosthesis. Each patient received both the autologous bone from the mandible (control) or porcine xenograft (test) during the random bilateral sinus lift surgery. A total of 39 dental implants were placed in the posterior maxilla of the 12 patients after 6 months, being rehabilitated after the respective osseointegration period. Both graft materials demonstrated a high implant survival rate at 12 months: 95% for the xenograft side, only 1 implant without osseointegration, and 100% for the autologous side. Radiographic bone loss was low and similar for both groups: control group with a mean of 0.063 ± 0.126, and test group with a mean of 0.092 ± 0.163. No major surgical-related complications have occurred. Only one patient had several prosthetic complications due to fractures of prosthetic components. The maxillary sinus augmentation procedure, both with autologous bone and porcine xenograft materials, is an excellent clinical option procedure for the prosthetic rehabilitation of atrophic maxillae, with low marginal bone loss after one year follow-up, few clinical complications, and a high implant survival rate.

A WNT protein therapeutic accelerates consolidation of a bone graft substitute in a pre-clinical sinus augmentation model

AIM

Autologous bone grafts consolidate faster than bone graft substitutes (BGSs) but resorb over time, which compromises implant support. We hypothesized that differences in consolidation rates affected the mechanical properties of grafts and implant stability, and tested whether a pro-osteogenic protein, liposomal WNT3A (L-WNT3A), could accelerate graft consolidation.

MATERIALS AND METHODS

A transgenic mouse model of sinus augmentation with immunohistochemistry, enzymatic assays, and histology were used to quantitatively evaluate the osteogenic properties of autografts and BGSs. Composite and finite element modelling compared changes in the mechanical properties of grafts during healing until consolidation, and secondary implant stability following remodelling activities. BGSs were combined with L-WNT3A and tested for its osteogenic potential.

RESULTS

Compared with autografts, BGSs were bioinert and lacked osteoprogenitor cells. While in autografted sinuses, new bone arose evenly from all living autograft particles, new bone around BGSs solely initiated at the sinus floor, from the internal maxillary periosteum. WNT treatment of BGSs resulted in significantly higher expression levels of pro-osteogenic proteins (Osterix, Collagen I, alkaline phosphatase) and lower levels of bone-resorbing activity (tartrate-resistant acid phosphatase activity); together, these features culminated in faster new bone formation, comparable to that of an autograft.

CONCLUSIONS

WNT-treated BGSs supported faster consolidation, and because BGSs typically resist resorption, their use may be superior to autografts for sinus augmentation.

Comparison of the effects of three different xenogeneic bone grafts used in sinus augmentation simultaneous with dental implant placement on the survival of the implants and the dimensional changes of the region

BACKGROUND

Xenografts can be produced in various particle sizes by using different bone types. Currently, there is no consensus about the ideal type of xenograft for sinus augmentations, and this choice depends on the personal experience of clinicians. This retrospective study aimed to evaluate the effects of three different xenografts used in sinus augmentation simultaneously with implant placement on the survival of the implants and the dimensional changes of the region.

METHODS

One hundred nine sinus augmentations and 164 implants were evaluated in 76 patients. Three different xenografts were used: 41 Gen-Os^® (250-1000µm, Corticocancellous; Tecnoss, Giaveno, Turin, Italy), 35 Bio-Oss^® (1000-2000µm, Cancellous; Geistlich Biomaterials italia S.r.l., Vicenza, Italy) and 33 Apatos-Cortical^® (600-1000µm, Cortical; Tecnoss). The preoperative, postoperative, and follow-up (21±8.8 month) radiographs were evaluated for the dimensional changes and the implant survivals. The data were statistically analyzed.

RESULTS

Among the implant failures; 3 (5.6%) in 53 implants in Apatos, 2 (3.6%) in 55 implants in Bio-Oss, 9 (16%) in 56 implants in Gen-Os, and 14 (8.5%) total implant failures were observed. This difference between the groups was statistically significant and was due to the high loss rate in the Gen-Os (P=0.044). There was a mean difference of -1.8±1.5mm between the measured bone heights on postoperative day (14.2±2.4mm) and the last follow-up (12.4±2.5 mm). While the loss of height was not affected due to the graft type (P=0.981), the general 12.6% vertical loss was statistically significant (P<0.0001), also the length of implants placed reduced this loss (P=0.036).

CONCLUSIONS

Within the limits of this retrospective study, it can be concluded that: 1) The sinus augmentation procedures with thicker particle size grafts achieved higher success rate; and 2) over the time, 12.6% loss may occur in the height of grafted area.

Clearance of Bone Substitute in Gel Form Accidentally Dispersed into the Sinus Cavity during Transcrestal Maxillary Sinus Floor Elevation: Two-Case Report

Sinus membrane perforation is the most frequent intraoperative complication occurring during maxillary sinus floor elevation. Although numerous techniques for perforation management are present, grafting material dissemination may still occur, representing a potential trigger factor leading to acute or chronic sinusitis. This case report describes two cases of xenogeneic bone substitute in gel form accidentally dispersed into the sinus cavity during maxillary sinus floor elevation with a transcrestal approach. In both cases, immediately postoperative radiographic imaging showed an important amount of gel graft dislodged into the sinus cavity as a consequence of hidden perforations that remained undetected during surgery. Patients were monitored for 6 months after surgery and reported no signs or symptoms related to possible sinus disease. Control radiographs showed no sinus membrane hypertrophy and/or presence of residual disseminated gel, confirming complete clearance of the accidentally dispersed graft through the ostiomeatal complex. In order to minimize postoperative complications, bone substitutes in gel form could represent an interesting alternative to granular grafts for their easier clearance from the maxillary sinus cavity in case of accidental dissemination during sinus augmentation procedures.

Patient's perception of recovery after sinus membrane elevation and blood coagulum compared with 1:1 mixture of autogenous bone graft and deproteinized porcine bone mineral. Secondary outcomes from a single-blinded randomized controlled trial

OBJECTIVE

The objective was to assess patient's perception of recovery after maxillary sinus membrane elevation (MSME) and blood coagulum (test) compared with maxillary sinus floor augmentation (MSFA) and 1:1 mixture of autogenous bone graft from the buccal antrostomy and deproteinized porcine bone mineral (DPBM) (control).

MATERIALS AND METHODS

Forty healthy patients were randomly allocated to test or control. Oral health-related quality of life (OHRQoL) was evaluated by Oral Health Impact Profile-14 (OHIP-14) at enrollment and 1 week postsurgical. Recovery was estimated by questionnaires and visual analog scale assessing pain, social and working isolation, physical appearance, eating and speaking ability, diet variations, sleep impairment, and discomfort after 1 week and 1 month. Mean differences were expressed with 95% confidence interval (CI). Association between OHRQoL and recovery was estimated. p-value below .05 was considered statistically significant.

RESULTS

Maxillary sinus membrane elevation revealed 2.1 less days of pain (p = .03, 95% CI: 0.2-4.1) and 1.2 days of sick leave (p = .01, 95% CI: 0.3-2.1) compared with MSFA. No significant difference was observed in eating and speaking ability, physical appearance, work performance, and sleep impairment. No significant association between impaired OHRQoL and recovery was observed. Females reported 4.77 higher OHIP-14 score compared with males (p = .01, 95% CI: 1.60-7.94), while association between age and OHIP-14 was -0.10 (p = .28, 95% CI: -0.28 to 0.08).

CONCLUSION

Maxillary sinus membrane elevation revealed significantly less days of pain and sick leave compared with MSFA. Harvesting of autogenous bone graft seems, therefore, to have a significant impact on perception of recovery.

Patient's perception of recovery after maxillary sinus floor augmentation with autogenous bone graft compared with composite grafts: a single-blinded randomized controlled trial

Background

Autogenous bone graft is considered as the preferred grafting material for maxillary sinus floor augmentation (MSFA). However, harvesting of extraoral or intraoral autogenous bone graft is associated with risk of donor site morbidity and supplementary surgery. From a clinical and patient perspective, it would therefore be an advantage, if postoperative discomfort could be minimized by diminishing the need for autogenous bone graft harvesting. The objective of the present study was to test the hypothesis of no difference in patient’s perception of recovery after MSFA with autogenous bone graft from the zygomatic buttress (control) compared with 1:1 mixture of autogenous bone graft and deproteinized porcine bone mineral (DPBM) (Test I) or biphasic bone graft material (BBGM) (Test II). Sixty healthy patients were randomly allocated to either control or test groups. Oral Health-related Quality of Life (OHRQoL) was evaluated by Oral Health Impact Profile-14 (OHIP-14) at enrollment. Recovery was estimated by self-administrated questionnaires and visual analog scale assessing pain, social and working isolation, physical appearance, eating and speaking ability, diet variations, sleep impairment and discomfort after 1 week and 1 month. Descriptive statistics was expressed as mean with standard deviation (SD). Correlation between OHRQoL at enrollment and recovery were assessed by linear regression. p-value below 0.05 was considered significant.

Results

Treatment satisfaction and willingness to undergo similar surgery were high in all groups. Average numbers of days with pain and sick leave were 3.5 (SD 3.9) and 0.5 (SD 1.2), respectively, with no significant difference between groups. Moreover, no significant difference in eating and speaking ability, physical appearance, work performance and sleep impairment were seen between groups. Mean OHIP-14 score at enrollment was 9.30 (SD 9.25) (control), 9.95 (SD 7.96) (Test I) and 8.15 (SD 9.37) (Test II), with no significant differences between groups. Impaired OHRQoL, gender or age seems not to predispose for delayed recovery or increased postoperative discomfort.

Conclusions

MSFA with diminutive autogenous bone graft harvesting is associated with high patient satisfaction, limited postoperative discomfort and willingness to undergo similar surgery. Presurgical OHRQoL, gender or age seems not to be associated with impaired patient’s perception of recovery.

Long-Term Clinical Study of Implants Placed in Maxillary Sinus Floor Augmentation Using Beta-Tricalcium Phosphate

Introduction. The aim of this study was to show the long-term clinical outcomes of implants placed in maxillary sinus floor augmentation (MFSA) using beta-tricalcium phosphate (β-TCP). Patients and methods. Maxillary patients were diagnosed for MFSA and used beta- β-TCP. After the lateral sinus surgery, implants were loaded at 6 months with restorations. The clinical follow-up was at 10 years. Results. One hundred and one patients (58 females and 43 males) were treated with MFSA. Twenty-nine patients (28.7%) had a history of periodontitis. Thirty-three patients (32.7%) were smokers. One hundred and twenty-one MFSA, 81 unilateral and 20 bilateral sites, with 234 implants were performed. The average vertical bone height available was 4.92 ± 1.83 mm. The average vertical bone gain obtained was 6.95 ± 2.19 mm following MFSA. The implant cumulative survival rate was 97.2%. Three implants (1.3%) were lost during the healing period. Six implants (2.6%) were lost by peri-implantitis. One hundred and fifteen restorations were placed in the patients. Mean marginal bone loss was 1.93 mm ± 1.03 mm. Six patients (27.3%) showed technical complications. Thirty-six implants (15.3%) in 14 patients (13.9%) were associated with peri-implantitis. Conclusions. This study indicates that treatment with implant-supported restoration by MFSA using β-TCP constitutes a successful implant approach.

Maxillary Sinus Floor Augmentation with Autogenous Bone Graft Compared with a Composite Grafting Material or Bone Substitute Alone: a Systematic Review and Meta-Analysis Assessing Volumetric Stability of the Grafting Material

Objectives

Test the hypothesis of no difference in the volumetric stability of the grafting material following maxillary sinus floor augmentation with autogenous bone graft compared with composite grafting material or bone substitute alone applying the lateral window technique.

Material and Methods

MEDLINE (PubMed), Embase, Cochrane library and hand-search of relevant journals were conducted. Human studies published in English until the 9^th of October 2020 were included. Outcome measures included three-dimensional volumetric changes of the grafting material and potential predictive parameters. Volumetric changes were evaluated by descriptive statistics and meta-analysis including 95% confidence interval.

Results

Electronic search and hand-searching resulted in 102 entries. Four randomized controlled trials with unclear risk of bias fulfilled the inclusion criteria. The volumetric stability of the grafting material was significantly improved by mixing autogenous bone graft with a non-resorbable xenograft compared with autogenous bone graft. Meta-analyses assessing absolute and relative volumetric changes demonstrated no significant differences between autogenous bone graft compared with allogeneic bone graft, synthetic biomaterials combined with autogenous bone graft or used alone. Association between volumetric changes of the grafting material and potential predictive parameters were not assessed in the included studies.

Conclusions

Volumetric reduction of the augmented area seems inevitable following maxillary sinus floor augmentation regardless of the grafting material. The volumetric stability of autogenous bone graft is improved with addition of xenograft compared with autogenous bone graft. However, conclusions drawn from this systematic review should be interpreted with caution since only four studies using three-dimensional radiographic measurements were included.

Relative performance of various biomaterials used for maxillary sinus augmentation: A Bayesian network meta-analysis

OBJECTIVES

To assess the histomorphometric outcomes obtained in randomized clinical trials (RCTs) with different biomaterials used for maxillary sinus augmentation (MSA).

MATERIALS AND METHODS

A search of the existing medical literature until October 1, 2019, was performed. Inclusion criteria were (a) RCTs assessing a two-stage MSA from the lateral approach using autologous bone or biomaterials for grafting and (b) reported histomorphometric outcomes based on crestal bone core biopsy samples. The Bayesian method was used to perform pairwise meta-analyses and network meta-analysis (NMA). The primary outcome, the new bone percentage (NB %), was calculated as mean differences with 95% credible intervals. The interventions were ranked by their posterior probability by calculating the surface under the cumulative ranking curve values.

RESULTS

Thirty-four RCTs (842 MSAs) were included in the analysis with a normal healing period (5-8 months). All comparisons were presented in a league table. On the basis of the ranking probability, the most effective bone grafting material for NB% was bovine xenograft + bone marrow concentrate (BMC) (81%), followed by bovine xenograft + platelet-rich plasma (PRP) (77%), bioactive glass ceramic + autologous bone 1:1 (70%), nanocrystalline hydroxyapatite in silica gel (70%), and bioactive glass ceramic (70%). Autologous bone graft alone took the twelfth position with 57%.

CONCLUSION

Within the limitations of the present NMA, the analysis did not confirm autologous bone alone as the gold standard for MSA and showed superiority of composite grafts such as bovine xenograft + BMC after 5-8 months of healing.

Bone regeneration of a polymeric sponge technique-Alloplastic bone substitute materials compared with a commercial synthetic bone material (MBCP+TM technology): A histomorphometric study in porcine skull

Background

Polymeric sponge technique is recommended for developing the desired porosity of Biphasic calcium phosphate (BCP) which may favor bone regeneration.

Purpose

To investigate the healing of BCP with ratio of HA30/β‐TCP70 (HA30) and HA70/β‐TCP30 (HA70) polymeric sponge preparation, compare to commercial BCP (MBCP+TM).

Materials and Methods

Materials were tested X‐ray diffraction (XRD) pattern and scanning electron microscope (SEM) analysis. In eight male pigs, six calvarial defects were created in each subject. The defects were the filled with 1 cc of autogenous bone, MBCP+TM (MBCP), HA30, HA70, and left empty (negative group). The new bone formations, residual material particles and bone‐to‐graft contacts were analyzed at 4, 8, 12 and 16 weeks.

Results

Fabricated BCP showed well‐distributed porosity. At 16 weeks, new bone formations were 45.26% (autogenous), 33.52% (MBCP), 24.34% (HA30), 19.43% (HA70) and 3.37% (negative). Residual material particles were 1.88% (autogenous), 17.58% (MBCP), 26.74% (HA30) and 37.03% (HA70). These values were not significant differences (Bonferroni correction <0.005). Bone‐to‐graft contacts were 73.68% (MBCP), which was significantly higher than 41.68% (HA30) and 14.32% (HA70; Bonferroni correction <0.017).

Conclusions

Polymeric sponge technique offers well‐distributed porosity. The new bone formation and residual material particles were comparable to MBCP+TM, but the bone‐to‐graft contact was lower than MBCP+TM.

Maxillary Sinus Floor Augmentation with Autogenous Bone Graft Alone Compared with Alternate Grafting Materials: a Systematic Review and Meta-Analysis Focusing on Histomorphometric Outcome

Objectives

The objective of present systematic review was to test the hypothesis of no difference in histomorphometric outcome after maxillary sinus floor augmentation with autogenous bone graft alone compared with alternate grafting materials applying the lateral window technique.

Material and Methods

MEDLINE (PubMed), Embase and Cochrane library search in combination with hand-search of relevant journals were conducted. Human studies published in English until the 25^th of March, 2020 were included. Histomorphometric outcomes were evaluated by descriptive statistics and meta-analysis including 95% confidence interval (CI).

Results

Electronic search and hand-searching resulted in 1902 entries. Sixteen randomized controlled trials with unclear risk of bias fulfilled the inclusion criteria. Descriptive statistics showed comparable or improved histomorphometric outcomes with autogenous bone graft. Meta-analysis revealed a mean difference of -7.1% (CI = -11.0 to -3.2) indicating a significant higher amount of bone after maxillary sinus floor augmentation with autogenous bone graft compared with alternate grafting materials. Subgroup analysis demonstrated a non-significantly differences of -3.7% (CI = -10.9 to 3.4), -11.5% (CI = -25.9 to 2.8), 2.2% (CI = -16.9 to 21.3), and -4.6% (CI = -14.4 to 5.2), when autogenous bone graft was compared with allogeneic bone graft, xenograft, composite grafting materials involving xenograft or synthetic biomaterial mixed with autogenous bone graft, respectively.

Conclusions

Maxillary sinus floor augmentation with autogenous bone graft seems to facilitate improved histomorphometric outcomes compared with alternate grafting materials. However, the included studies were characterised by an unclear risk of bias and various methodological confounding factors. Hence, the conclusions drawn from the results of present study should be interpreted with caution.

Biomimetic Aspects of Oral and Dentofacial Regeneration

Biomimetic materials for hard and soft tissues have advanced in the fields of tissue engineering and regenerative medicine in dentistry. To examine these recent advances, we searched Medline (OVID) with the key terms “biomimetics”, “biomaterials”, and “biomimicry” combined with MeSH terms for “dentistry” and limited the date of publication between 2010–2020. Over 500 articles were obtained under clinical trials, randomized clinical trials, metanalysis, and systematic reviews developed in the past 10 years in three major areas of dentistry: restorative, orofacial surgery, and periodontics. Clinical studies and systematic reviews along with hand-searched preclinical studies as potential therapies have been included. They support the proof-of-concept that novel treatments are in the pipeline towards ground-breaking clinical therapies for orofacial bone regeneration, tooth regeneration, repair of the oral mucosa, periodontal tissue engineering, and dental implants. Biomimicry enhances the clinical outcomes and calls for an interdisciplinary approach integrating medicine, bioengineering, biotechnology, and computational sciences to advance the current research to clinics. We conclude that dentistry has come a long way apropos of regenerative medicine; still, there are vast avenues to endeavour, seeking inspiration from other facets in biomedical research.

Dimensional changes of the maxillary sinus augmented with a collagenated synthetic bone block or synthetic bone particulates: A pre-clinical study in rabbits

OBJECTIVE

To compare the efficacy of a collagenated synthetic bone substitute (C-SBS) to a particulated synthetic bone substitute (P-SBS) in volume maintenance and new bone formations in a rabbit sinus model.

MATERIALS AND METHODS

Either C-SBS or P-SBS was grafted in both sinuses of 16 rabbits. Four (N = 8) or 12 (N = 8) weeks after the surgery, total augmented volume (TAV) and area (TAA), as well as new bone volume (NBV) and area (NBA), were statistically compared by radiographic and histomorphometric analyses (p < .05).

RESULTS

The differences in TAV, NBV, TAA and NBA between C-SBS and P-SBS groups at 4 weeks were not statistically significant. The TAV (267.13 ± 62.08 vs. 200.18 ± 40.32 mm³ ) and NBV (103.26 ± 10.50 vs. 71.10 ± 7.58 mm³ ) in group C-SBS were significantly higher than in group P-SBS at 12 weeks (p < .05). The TAA (19.36 ± 2.88 vs. 14.48 ± 2.08 mm² ) and NBA (5.43 ± 1.20 vs. 3.76 ± 0.78 mm² ) in group C-SBS were significantly higher than in group P-SBS at 12 weeks (p < .05).

CONCLUSIONS

Collagenated synthetic bone substitute grafted in rabbit sinuses demonstrated more favourable outcomes across all outcome measures compared to P-SBS at 12 weeks.

Sandwich osteotomy of the atrophic posterior mandible with interpositional autogenous bone block graft compared with bone substitute material: a systematic review and meta-analysis

The objective of the present systematic review was to test the hypothesis that there were no differences in outcome of implant treatment after sandwich osteotomy in the atrophic posterior mandible with interpositional autogenous bone block graft, compared with bone substitute material. A MEDLINE/PubMed, Embase and Cochrane Library search in combination with hand-search of selected journals was conducted. Two short-term randomised controlled trials with a split-mouth study design and low risk of bias fulfilled the inclusion criteria. High survival rate of suprastructures and implants was disclosed with no significant difference between interpositional autogenous bone block graft compared with bone substitute material. Meta-analysis revealed patient-based implant survival risk ratio of 1.05 (95% CI: 0.88 to 1.25) and peri-implant marginal bone loss of 0.31mm (95% CI: -0.29 to 0.90) indicating no significant differences between the two treatments. High implant stability values, gain in vertical alveolar ridge height, bone formation, and few complications were reported with both treatments. Sandwich osteotomy with interpositional grafting material appears to be a predictable surgical technique for enhancement of the vertical alveolar ridge height in the atrophic posterior mandible prior to implant placement.

Sequential healing of the elevated sinus floor with different size of antrostomy: a histomorphometric study in rabbits

PURPOSE

To study the influence of the access window dimensions on the healing at the antrostomy and within the augmented maxillary sinus.

MATERIAL AND METHODS

A maxillary sinus augmentation was performed in twenty-four albino New Zealand rabbits. Antrostomies of 3 × 6 mm (small) or 5 × 6 mm (large) in dimensions were randomly prepared in each animal. A collagenated cortico-cancellous porcine bone was used to fill the elevated region, and an equine collagen membrane was placed on the antrostomies. Three different groups were formed, based on the time of euthanasia, i.e., 2, 4, and 8 weeks from surgery.

RESULTS

No relevant changes of the height of the augmented sinus were detected over time. Mineralized bone increased between 2 and 4 weeks of healing while remained stable between 4 and 8 weeks. The highest amounts of new bone were found close to the sinus bone walls. No antrostomies were found healed with an even layer of corticalized bone, while large amounts of connective tissue were occupying the antrostomy in both groups.

CONCLUSION

Antrostomies of different dimensions resulted in similar outcome in bone formation both in the antrostomy regions and within the elevated sinus.

Therapeutic outcomes of non-grafted and platelet concentrations-grafted transcrestal maxillary sinus elevation (TSFE): a systematic review and meta-analysis

To evaluate and compare the stability, quantity and quality of bone augmentation at maxillary sinus elevation sites by non-grafted transcrestal sinus floor elevation (TSFE) and platelet concentration grafted transcrestal sinus floor elevation (PC-TSFE). A complete literature search was performed up to April 2019. Clinical controlled trials, retrospective cohort studies, and prospective cohort studies were selected based on inclusion criteria. The clinical outcomes were implant survival rate (ISR), marginal/crestal bone loss (MBL/CBL) and endo-sinus bone gain (ESBG). Meta‐analysis was conducted on these 1-year based values. Furthermore, another meta-analysis on 1-year ISR value was conducted among studies with different residual bone heights (RBH) within the non-grafted TSFE group. A total of 18 studies were included: 13 in TSFE group and 5 in PC-TSFE group. No significant differences were displayed between the 1-year ISR of TSFE (97%, 95%CI = 0.96–0.99) and PC-TSFE group (99%, 95%CI = 0.97–1.00). Among the various studies with different RBH within TSFE group, no significant differences in 1-year ISR were displayed. The 1-year MBL/CBL value of PC-TSFE group (0.73 mm, 95%CI = 0.43–1.13 mm) did not show significant difference as compared to TSFE group (0.60 mm, 95%CI = 0.10–1.10 mm). Furthermore, no significant enhancement was observed on 1-year ESBG value on PC-TSFE group (3.51 mm, 95%CI = 2.31–4.71 mm) in comparison with the TSFE group (2.87 mm, 95%CI = 2.18m–3.55 mm). Grafting platelet concentrations around dental implants at TSFE sites did not significantly enhance the adjacent bone regeneration. Moreover, TSFE was shown to be a reliable therapeutic option for implant sites that need simultaneous maxillary sinus augmentation, even under limited RBH.

Maxillary Sinus Floor Augmentation With or Without Barrier Membrane Coverage of the Lateral Window: a Systematic Review and Meta-Analysis

Objectives

Test the hypothesis of no difference in implant treatment outcomes after maxillary sinus floor augmentation with or without barrier membrane coverage of the lateral window.

Material and Methods

A MEDLINE (PubMed), Embase and Cochrane library search in combination with a hand-search of relevant journals was conducted. Human studies published in English until the 5th of July, 2019 were included. Randomised controlled trials and controlled trials with an observation period of minimum six months were included. Primary outcomes included survival of suprastructures and implants. Secondary outcomes included implant stability quotient, peri-implant marginal bone loss, bone regeneration, patient-reported outcome measures, biologic and mechanical complications.

Results

The electronic search and hand-searching resulted in 1068 entries. Six randomised controlled trials characterised by low to high risk of bias and one controlled trial with high risk of bias fulfilled the inclusion criteria. High implant survival rate was reported with both treatment modalities. Meta-analyses disclosed a mean difference of newly formed bone of 6.4% (confidence interval = 0 to 12.9) and non-mineralised tissue of -1.1% (confidence interval = -2.7 to 0.5), indicating more newly formed bone and diminished non-mineralised with barrier membrane coverage.

Conclusions

There seem to be no statistically significant differences in implant treatment outcomes after maxillary sinus floor augmentation with or without barrier membrane coverage of the lateral window. However, barrier membrane coverage increases percentage of newly formed bone and diminishes proliferation of non-mineralised tissue. Thus, barrier membrane coverage seems to be beneficial and also preventing displacement of the grafting material.

Sinus Floor Elevation and Antrostomy Healing: A Histomorphometric Clinical Study in Humans

OBJECTIVES

To compare the histomorphometric outcomes of biopsies collected from the antrostomy and from the alveolar crest of the maxillary sinus after a sinus-lift procedure.

MATERIAL AND METHODS

In 12 volunteers, sinus floor elevation was performed using collagenated corticocancellous porcine bone. Nine months after the surgery, 2 biopsies, 1 from the alveolar crest and 1 from the antrostomy, were collected for histological analysis.

RESULTS

Biopsies from 11 patients were available for histological analyses (n = 11). At the alveolar crest sites, the percentage of mineralized bone was 40.1 ± 14.1%, of bone marrow was 40.1 ± 18.0%, and of the xenograft was 14.7 ± 15.2%. Small amounts of soft tissue were found. At the antrostomy sites, the percentages of mineralized bone, bone marrow, and xenograft were 26.0 ± 10.8%, 23.4 ± 17.0%, and 28.2 ± 15.7%, respectively. Soft tissue was represented by 19.7 ± 19.4%.

CONCLUSION

Higher amounts of mineralized bone and bone marrow were found in the alveolar crest compared with the antrostomy.

Fresh Frozen Allogeneic Bone Block in Maxillary Sinus Floor Elevation: Histomorphometric Analysis of a Bone Specimen Retrieved 15 Years after Grafting Procedure

Nowadays implant-prosthetic rehabilitations are one of the best solutions for rehabilitating our patients. These allow obtaining rehabilitations with optimal functional and aesthetic performances. Often patients, who undergo implant-prosthetic therapy, have the conditions of edentulias, single or multiple, that have been going on for some time. This, according to the literature, produces resorption of the alveolar bone, a process that is complicated in the posterior area of the upper arch by a pneumatization of the maxillary sinuses. The loss of vertical height, so that the implant fixtures can be inserted, requires a maneuver called maxillary sinus floor elevation. This procedure, now safely performed with piezoelectric instruments, allows increasing bone height through bone grafting. In this study, the tissue obtained from a patient, after 15 years from the intervention, was evaluated by histological and SEM analyses. The bone healing in the patient has led to a perfect integration between the patient’s bone and the fresh frozen allograft used, however still present and detectable after 15 years.