Bioactive glass added to autogenous bone graft in maxillary sinus augmentation: a prospective histomorphometric, immunohistochemical, and bone graft resorption assessment

A Histologic, Histomorphometric, and Immunohistochemical Evaluation of Anorganic Bovine Bone and Injectable Biphasic Calcium Phosphate in Humans: A Randomized Clinical Trial

Following trauma, chronic periapical process, or tooth extraction, a large loss of bone volume is noticed during the healing process. To facilitate the placement of dental implants, various surgical procedures are used for an optimal alveolar ridge profile, while maintaining adequate bone dimensions. The main aim of this study was to determine the healing ability (histologically and immunohistologically) of alveolar bone defects during augmentation with two different biomaterials: injectable biphasic calcium phosphate (BCP) and anorganic bovine bone (ABB). Thirty-eight subjects were randomly divided into two groups. The first group received the tested bone substitute biomaterial (BSB), i.e., BCP (maxresorb inject®), and the second group received an alternative to the gold standard, i.e., ABB (Bio-Oss®). The histopathological, histomorphometric, and immunohistochemical analyses gave comparable results for these bone substitute materials in terms of newly formed bone: (BCP: 39.91 ± 8.49%, ABB: 41.73 ± 13.99%), residual biomaterial (BCP: 28.61 ± 11.38%, ABB: 31.72 ± 15.52%), and soft tissue (BCP: 31.49 ± 11.09%, ABB: 26.54 ± 7.25%), with no significant difference found between the groups (p < 0.05, t-test), proving that BCP is equally suitable and successful for alveolar bone regeneration.

Residual Bone Height and New Bone Formation after Maxillary Sinus Augmentation Procedure Using Biomaterials: A Network Meta-Analysis of Clinical Trials

BACKGROUND

Different factors may affect new bone formation following maxillary sinus floor augmentation for the rehabilitation of posterior edentulous maxilla. The purpose of this study was to determine the influence of residual bone height (RBH) on new bone formation after lateral sinus augmentation utilizing different biomaterials, through a network meta-analysis (NMA).

METHODS

PUBMED, Scopus, and Web of Science electronic databases were searched until 31 December 2022 to obtain relevant articles. A hand search was also conducted. Randomised controlled studies on maxillary sinus augmentation comparing different grafting materials in patients with atrophic posterior maxilla, in need of prosthetic rehabilitation, were included. The risk of bias was assessed following the guidelines of the Cochrane Collaboration. The primary outcome was new bone formation (NBF), assessed histomorphometrically. The statistical analysis was performed by splitting the data according to RBH (<4 mm and ≥4 mm).

RESULTS

A total of 67 studies were eligible for conducting NMA. Overall, in the included studies, 1955 patients were treated and 2405 sinus augmentation procedures were performed. The biomaterials used were grouped into: autogenous bone (Auto), xenografts (XG), allografts (AG), alloplasts (AP), bioactive agents (Bio), hyaluronic acid (HA), and combinations of these. An inconsistency factor (IF) seen in the entire loop of the XG, AP, and Bio+AP was found to be statistically significant. The highest-ranked biomaterials for the <4 mm RBH outcome were XG+AG, XG+AP, and Auto. Similarly, the surface under the cumulative ranking curve (SUCRA) of biomaterials for ≥4 mm RBH was Auto, Bio+XG, and XG+Auto.

CONCLUSION

There is no grafting biomaterial that is consistently performing better than others. The performance of the materials in terms of NBF may depend on the RBH. While choosing a biomaterial, practitioners should consider both patient-specific aspects and sinus clinical characteristics.

The Role of Bone Grafts in Preventing Medication-Related Osteonecrosis of the Jaw: Histomorphometric, Immunohistochemical, and Clinical Evaluation in Animal Model

Objective

To evaluate the effects of inorganic bovine bone graft (Lumina Bone, Criteria, Brazil) and beta-tricalcium phosphate (β-TCP) graft (ChronOS, Synthes, Brazil) in rats with the risk of developing post-extraction medication-related osteonecrosis of the jaw (MRONJ).

Methods

Eighteen male Wistar rats weighing 350 to 450 g were induced to develop MRONJ using zoledronic acid for 5 weeks. In the sixth week, the right maxillary first molar was extracted. The animals in Group I (G1) did not receive bone grafts after tooth extraction, while Group II (G2) animals received inorganic bovine bone grafts, and Group III (G3) animals received beta-tricalcium phosphate (β-TCP) grafts. Clinical evaluation and histomorphometric and immunohistochemical analyses were performed. ANOVA and Tukey's statistical tests were used and a level of significance was considered to be 5%.

Results

In the clinical evaluation, animals from G2 and G3 did not present clinical manifestations of osteonecrosis, unlike the control group (G1) animals, which presented necrotic bone tissue exposure in all samples. In the histomorphometric evaluation, animals in G3 showed greater formation of bone tissue (66%) and less formation of bone lacuna (18%) than animals in G1 (58%/32%) and in G2 (59%/27%) (P < 0.05). Moderate (++) immunostaining was observed in G2 and G3 for RANKL, TRAP, and OC, while G1 showed moderate (++) labeling for OC and mild (+) immunostaining for TRAP and RANKL.

Conclusions

Greater formation of bone tissue and fewer bone lacunae were found in animals treated with β-TCP. In clinical evaluation, bone graft groups presented with the clinical manifestation of MRONJ and showed higher intensity of immunostaining for TRAP and RANKL. Despite the limitations of experimental animal studies, the results of this work may assist in the development of future clinical research for the prevention of MRONJ.

Autogenous Bone and Bioactive Glass around Implants Placed Simultaneously with Ridge Splitting for the Treatment of Horizontal Bony Defects: A Randomised Clinical Trial

Objective

To compare using autogenous bone with or without bioactive glass in ridge splitting of horizontal bone defects combined with simultaneous implant placement.

Materials and Methods

In control group, bone expansion was performed and autogenous bone was used to augment the intercortical bone defect. In study group, autogenous bone was mixed with bioactive glass (1 : 1 in volume). In both groups, the implants were inserted simultaneously with ridge splitting. Six months following implant insertion, bone width and height were evaluated. Statistical analysis utilizing paired Student's t-test was used for comparing results within the same group, whereas independent samples t-test was used for intergroup variables comparison.

Results

The mean bone width and labial and mesiodistal crestal bone height values were increased significantly in both groups from baseline to 6 months postoperatively. Comparing the two groups showed nonstatistical significant difference regarding the labial crestal bone loss, while the ridge width gain values were significantly higher in the study group than in the control group. The mesiodistal bone loss was significantly higher in control group than in study group.

Conclusion

Autogenous bone was mixed with bioactive glass (1 : 1 in volume) to fill intercortical defect created after ridge splitting to decrease peri-implant bone resorption associated with autogenous bone alone. This trial is registered with clinical trial registration: NCT04814160.

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.

Three-dimensional volumetric changes of 5 different bone grafts in human maxillary sinuses reconstruction: a randomized clinical study

PURPOSE

This study aimed to compare the three-dimensional volumetric changes of human maxillary sinuses after reconstruction using 5 different bone grafts.

PATIENTS AND METHODS

Patients underwent unilateral maxillary sinus bone height reconstruction using 5 bone substitutes allocated in different groups as follows: group 1 was grafted with autogenous bone graft alone; group 2 with beta-tricalcium phosphate (β-TCP); group 3 with β-TCP + autogenous bone graft 1:1; group 4 with bioactive glass; and group 5 with bioactive glass + autogenous bone graft 1:1. The patients were submitted to cone beam computed tomography in two periods: 15 days after the surgical procedure (T1) and after 6 months (T2). The results were evaluated as the formula T2-T1 expressing the three-volumetric changes of the biomaterials in elapsed time.

RESULTS

The resorption rate of autogenous bone graft was -630.699 ± 300.9 mm³; in the β-TCP group, it was -315.772 ± 125.6 mm³; in the group with β-TCP + autogenous bone graft 1:1, it was -336.205 ± 195.7 mm³; and in groups with bioactive glass and with the addition of autogenous bone graft 1:1, it was -428.878 ± 311.6 mm³ and -576.917 ± 471.6 mm³, respectively, without statistical difference (p = 0.167). Pearson's correlated test revealed a strong correlation as well as a progressive resorption of the grafts during bone healing.

CONCLUSION

The similar outcomes for the three-dimensional volumetric changes using the bone substitutes evaluated after 6 months of bone healing suggest that all these grafts can be performed to maxillary sinus reconstruction.

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.

The new bone formation in human maxillary sinuses using two bone substitutes with different resorption types associated or not with autogenous bone graft: a comparative histomorphometric, immunohistochemical and randomized clinical study

OBJECTIVE

The aim of this study is to evaluate the new bone and connective tissue formation and the biomaterial remaining after maxillary sinus bone augmentation using 5 different bone substitutes. The osteocalcin immunolabeling was performed to demonstrate their calcification and the possibility of receiving dental implants.

METHODOLOGY

40 patients underwent maxillary sinus bone augmentation and were divided in 5 groups: Group 1 with 8 maxillary sinuses were grafted with autogenous bone graft (AB); Group 2 with 8 maxillary sinuses grafted with bioactive glass (BG); Group 3 with 8 maxillary sinuses grafted with bioactive glass added to autogenous bone graft (BG + AB) 1:1; Group 4 with 8 maxillary sinuses grafted with Bio-Oss (BO) and Group 5 with 8 maxillary sinuses grafted with Bio-Oss added to autogenous bone graft (BO + AB) 1:1.

RESULTS

In group AB, 37.8% of bone was formed in the pristine bone region, 38.1% in the intermediate and 44.5% in the apical region. In group BG, 43.6% was formed in the pristine bone, 37% in the intermediate and 49.3% in the apical region. In group BG + AB 1:1, 39.0% was formed in the pristine bone region, 34.8% in the intermediate and 36.8% in apical region. In group BO, 33.4% was formed in the pristine bone, 32.5% in the intermediate and 34.3% in the apical region. In group BO + AB 1:1, 32.8% was formed in the pristine bone, 36.1% in intermediate and 27.8% in the apical regions. The immunolabeling for osteocalcin showed an intensive staining for all groups, which could demonstrate the calcification of the bone formed.

CONCLUSION

This study showed that the groups evaluated formed a suitable lamellar bone in the maxillary sinus reconstruction after six months of bone healing, thus being indicated to receive dental implants.

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.

Full Regeneration of Maxillary Alveolar Bone Using Autogenous Partially Demineralized Dentin Matrix and Particulate Cancellous Bone and Marrow for Implant-Supported Full Arch Rehabilitation

Autogenous partially demineralized dentin matrix (APDDM) has been reportedly used as a superior bone graft material. A 52-year-old Japanese man who exhibited severe periodontitis was referred for oral rehabilitation. He underwent wide-range anterior maxillary alveolar bone and bilateral sinus floor augmentation by grafting of a mixture of APDDM and particulate cancellous bone and marrow (PCBM); subsequently, he underwent implant-supported full arch rehabilitation. He has been followed up for 4 years after placement of the final restoration without any complications, and his physiological bone volume has been maintained. APDDM constitutes an alternative treatment that may increase the volume of graft material and might prevent rapid resorption of PCBM, because APDDM served as a scaffold for osteoblasts from PCBM. When possible, it may be useful to apply APDDM as a graft material with PCBM for large-volume alveolar bone regeneration.

Uma atualização sobre biomateriais em implantodontia

O processo alveolar é uma estrutura dente dependente que sofre alterações dimensionais após a exodontia. Defeitos ósseos resultantes prejudicam a colocação de implantes e o sucesso em longo prazo. Diversas técnicas cirúrgicas e biomateriais tem sido apresentados como opções terapêuticas para preservação e recuperação dos rebordos edêntulos. Assim, o objetivo desta revisão narrativa é evidenciar o estado atual dos biomateriais disponíveis bem como as possíveis perspectivas futuras. A utilização de biomateriais para cirurgias de reconstrução e manutenção de rebordo alveolar com sucesso é evidente. A impressão em 3D de estruturas biocompatíveis, fatores de crescimento, as DDMs, parafusos e membranas reabsorvíveis podem ser as perspectivas futuras.