Volumetric assessment of changes in the alveolar ridge dimension following GBR using a combination FDBA with collagen membrane or novel resorbable scaffold: A prospective two-center clinical trial

Clinical, Radiological, and Histomorphometric Comparison of the Use of Deproteinized Bovine Bone Mineral and Titanium-Prepared Platelet-Rich Fibrin in Maxillary Sinus Augmentation: A Split-Mouth Randomized Controlled Clinical Study

BACKGROUND

Maxillary sinus augmentation (MSA) is a standard and predictable procedure to increase bone height in the atrophic posterior maxilla. Many biomaterials are employed in this technique; however, autologous platelet concentrates have been found to reduce clinical recovery time and improve bone gain in MSA.

PURPOSE

This study aimed to compare the radiographic, histomorphometric, and implant stability outcomes of titanium-prepared platelet-rich fibrin (T-PRF) and deproteinized bovine bone mineral (DBBM) in a two-stage MSA technique.

STUDY DESIGN, SETTING, SAMPLE

This randomized controlled split-mouth study included patients requiring bilateral two-stage MSA at the Periodontology Department of Kutahya Health Sciences University between March 2022 and April 2023. Patients with systemic comorbidities and residual bone height >5 mm in the bilateral posterior maxilla were excluded.

PREDICTOR VARIABLE

The predictor variable was the two-stage MSA technique. Each surgical site was randomly assigned to the T-PRF or DBBM group for two-stage MSA.

MAIN OUTCOME VARIABLES

The primary outcome was the histomorphometric evaluation of the percentage of new bone between the 2 groups. Secondary outcomes included radiographic evaluation of total bone height (ToBH), bone gain, bone density (BD), and graft volume (GV) on cone-beam computed tomography 6 months post-MSA, clinical assessment of primary implant stability at implant placement and secondary stability 3 months postplacement, and histomorphometric evaluation of the percentage of residual particles, percentage of connective tissue, and percentage of blood vessels from bone biopsy samples collected 6 months after MSA.

COVARIATES

Age, sex, periodontitis susceptibility, and smoking status were treated as covariates.

ANALYSES

The Wilcoxon signed-rank test was used for bivariate comparisons between 2 groups, and the Pearson or Spearman test was used to analyze correlations of variables within groups. A P value ≤ .05 was considered statistically significant.

RESULTS

The sample was composed of 10 patients with bilateral maxillary sinuses, 20 MSA regions, 8 (80%) males and 2 (20%) females with a mean age of 51.30 (9.06) year. The percentage of new bone was 19.48 ± 14.60 μm2 in the T-PRF group and 8.31 ± 5.47 μm2 in the DBBM group, and there was no statistically significant difference between the groups (P = .074). Radiographic measurements showed ToBH, GV, and BD values of 10.64 ± 3.96 mm, 989.89 ± 523.07 mm3, and 192.09 ± 127.90 hounsfield unit in the T-PRF group and 14.25 ± 1.65 mm, 1,519.39 ± 432.61 mm3, and 492.77 ± 117.35 hounsfield unit in the DBBM group, respectively. ToBH, GV, and BD values were statistically significant between the groups (P = .01 and P = .00). Primary and secondary implant stability in the T-PRF group were 71.11 ± 12.48 implant stability quotient (ISQ) and 68.03 ± 6.81 ISQ, respectively, compared with 67.94 ± 19.84 ISQ and 72.46 ± 11.21 ISQ in the DBBM group. The difference was not statistically significant between the groups (P = .41 and P = .33).

CONCLUSION AND RELEVANCE

Although T-PRF demonstrated inferior radiographic outcomes compared with DBBM during the initial6-month healing phase, both techniques yielded comparable results regarding new bone formation and implant stability. Further research is warranted to explore the efficacy of different T-PRF applications in MSA. This trial is registered at ClinicalTrials.gov (NCT05596084).

Association between prosthesis contour and peri-implantitis in patients compliant with supportive periodontal therapy: A retrospective cohort study

PURPOSE

Poor contour of the implant restoration causes plaque accumulation and increases the risk of peri-implantitis. This study aimed to investigate whether the prosthodontic components of dental implants were associated with the prevalence of peri-implantitis.

METHODS

We enrolled 185 patients with 348 implants who underwent at least 1-year follow-up after the delivery of the prosthesis from February 2010 to January 2021. Demographic data of the patients and implants and the follow-up period were recorded. The emergence angle, type of cervical crown contour, and contour angle were analyzed using annual bite-wing radiographs. Peri-implantitis in this study was diagnosed if the peri-implant bone loss was greater than 2 mm between the bite-wing radiographs taken at baseline and the latest. Chi-square test, two-sample t-test, and multivariate logistic regression were used to investigate the differences and odds ratios between the peri-implantitis and non-peri-implantitis groups.

RESULTS

The incidence of peri-implantitis was 14.9% during a follow-up period of 1509 days after the delivery of the prosthesis for at least 1-year. Based on the prevalence of non-peri-implantitis and after adjusting for confounding factors, the risk factors identified were bone types for implants (native bone vs. alveolar ridge preservation: adjusted odds ratio = 2.43, P = 0.04). Sex, arch, and guided bone regeneration vs. alveolar ridge preservation have the potential for a statistical difference.

CONCLUSIONS

Compared with implants at alveolar ridge preservation sites, implants in the native bone were more prone to peri-implantitis. Further randomized controlled trials are required to determine these associations.

Biomaterial scaffolds in maxillofacial bone tissue engineering: A review of recent advances

Maxillofacial bone defects caused by congenital malformations, trauma, tumors, and inflammation can severely affect functions and aesthetics of maxillofacial region. Despite certain successful clinical applications of biomaterial scaffolds, ideal bone regeneration remains a challenge in maxillofacial region due to its irregular shape, complex structure, and unique biological functions. Scaffolds that address multiple needs of maxillofacial bone regeneration are under development to optimize bone regeneration capacity, costs, operational convenience. etc. In this review, we first highlight the special considerations of bone regeneration in maxillofacial region and provide an overview of the biomaterial scaffolds for maxillofacial bone regeneration under clinical examination and their efficacy, which provide basis and directions for future scaffold design. Latest advances of these scaffolds are then discussed, as well as future perspectives and challenges. Deepening our understanding of these scaffolds will help foster better innovations to improve the outcome of maxillofacial bone tissue engineering.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of the 2022 dental literature to briefly touch on several topics of interest to modern restorative dentistry. Each committee member brings discipline-specific expertise in their subject areas that include (in order of the appearance in this report): prosthodontics; periodontics, alveolar bone, and peri-implant tissues; dental materials and therapeutics; occlusion and temporomandibular disorders; sleep-related breathing disorders; oral medicine and oral and maxillofacial surgery; and dental caries and cariology. The authors focused their efforts on reporting information likely to influence the daily dental treatment decisions of the reader with an emphasis on innovations, new materials and processes, and future trends in dentistry. With the tremendous volume of literature published daily in dentistry and related disciplines, this review cannot be comprehensive. Instead, its purpose is to update interested readers and provide valuable resource material for those willing to subsequently pursue greater detail on their own. Our intent remains to assist colleagues in navigating the tremendous volume of newly minted information produced annually. Finally, we hope that readers find this work helpful in managing patients.

Collagen-Based Biomaterials for Tissue Engineering

Collagen is commonly used as a regenerative biomaterial due to its excellent biocompatibility and wide distribution in tissues. Different kinds of hybridization or cross-links are favored to offer improvements to satisfy various needs of biomedical applications. Previous reviews have been made to introduce the sources and structures of collagen. In addition, biological and mechanical properties of collagen-based biomaterials, their modification and application forms, and their interactions with host tissues are pinpointed. However, there is still no review about collagen-based biomaterials for tissue engineering. Therefore, we aim to summarize and discuss the progress of collagen-based materials for tissue regeneration applications in this review. We focus on the utilization of collagen-based biomaterials for bones, cartilages, skin, dental, neuron, cornea, and urological applications and hope these experiences and outcomes can provide inspiration and practical techniques for the future development of collagen-based biomaterials in related application fields. Moreover, future improving directions and challenges for collagen-based biomaterials are proposed as well.

Three-dimensional volumetric assessment of hard tissue alterations following horizontal guided bone regeneration using a split-thickness flap design: A case series

OBJECTIVES

To analyze morphological, volumetric, and linear hard tissue changes following horizontal ridge augmentation using a three-dimensional radiographic method.

METHODS

As part of a larger ongoing prospective study, 10 lower lateral surgical sites were selected for evaluation. Horizontal ridge deficiencies were treated with guided bone regeneration (GBR) using a split-thickness flap design and a resorbable collagen barrier membrane. Following the segmentation of baseline and 6-month follow-up cone-beam computed tomography scans, volumetric, linear, and morphological hard tissue changes and the efficacy of the augmentation were assessed (expressed by the volume-to-surface ratio).

RESULTS

Volumetric hard tissue gain averaged 605.32 ± 380.68 mm³. An average of 238.48 ± 127.82 mm³ hard tissue loss was also detected at the lingual aspect of the surgical area. Horizontal hard tissue gain averaged 3.00 ± 1.45 mm. Midcrestal vertical hard tissue loss averaged 1.18 ± 0.81 mm. The volume-to-surface ratio averaged 1.19 ± 0.52 mm³/mm². The three-dimensional analysis showed slight lingual or crestal hard tissue resorption in all cases. In certain instances, the greatest extent of hard tissue gain was observed 2-3 mm apical to the initial level of the marginal crest.

CONCLUSIONS

With the applied method, previously unreported aspects of hard tissue changes following horizontal GBR could be examined. Midcrestal bone resorption was demonstrated, most likely caused by increased osteoclast activity following the elevation of the periosteum. The volume-to-surface ratio expressed the efficacy of the procedure independent of the size of the surgical area.

Custom Bone Regeneration (CBR): An Alternative Method of Bone Augmentation-A Case Series Study

We performed this clinical study in order to evaluate the reliability of the Guided Bone Regeneration (GBR) surgical technique through the use of customized CAD CAM titanium meshes (Yxoss CBR^® Reoss) in order to show an alternative method of bone augmentation.

MATERIALS AND METHODS

Nine patients presenting 10 bone defects were referred to solve oral dysfunction due to edentulous atrophic ridges. Guided bone regeneration was performed with titanium meshes combined with autogenous bone grafting and heterologous bovine bone mineral grafting, and exclusively a "poncho technique" soft tissue approach for all the cases. After a mean 9 months of graft healing (range 6-12 months), titanium meshes were removed, and implant surgery was subsequently performed. The results we obtained were positive in terms of volumetric increases in height, length and thickness of the atrophic ridges without biological complications detectable before implant surgery.

RESULTS

Out of nine, one site met titanium mesh exposure: however, in all 10 sites a three-dimensional volumetric bone implementation was obtained. The statistical results were estimated by uploading and superimposing cbct scans before and after CBR surgery for each patient, so it was possible evaluate the maximum linear vertical and horizontal bone gain through dedicated Cad Cam software (Exocad GmbH^®). The average horizontal gain was 6.37 ± 2.17 mm (range 2.78-9.12 mm) and vertical gain was 5.95 ± 2.06 mm (range 2.68-9.02 mm). A total of 18 implants were placed into the grafted sites with a 100% survival rate (clearly they are relative percentages to be compared to the short time elapsed).

CONCLUSIONS

The results we obtained in this study suggest that this CBR procedure (Yxoss^® by Reoss) is reliable and safe for bone regeneration to allow implant-prosthetic restoration in horizontal, vertical and combined bone defects. The soft tissue management is diriment: all the cases were managed with a "poncho" flap approach to decrease exposure complication.

Immediate implant placement vs. early implant treatment in the esthetic area. A 1-year randomized clinical trial

OBJECTIVES

To assess the impact of implant placement and temporization timing on esthetic outcomes of single maxillary anterior implants with intact bone walls and interproximal bone.

MATERIALS AND METHODS

Test group patients received an immediate implant with immediate provisional restoration and socket preservation, while patients in the control group received an early implant placement with guided bone regeneration and delayed loading. Patients were followed for 1 year after final prosthetic and pink esthetic score (PES), mid-buccal mucosal level (MBML), crestal bone changes (CBC), and peri-implant soft tissue parameters, and patient chair time was recorded.

RESULTS

Fifty patients received the intended treatment (25 test and 25 control). No implants failed. PES after 1 year was 12.8 ± 1.19 for the test group and 12.5 ± 1.36 for the control group (p = .362). MBML difference between baseline (after final crown delivery) and the 1-year follow-up was gain of 0.2 ± 1.02 mm for the test group (p = .047) and no change in the control group. CBC after 1 year were 0.1 mm ± 0.21 mm (mesial) and 0.2 mm ± 0.22 mm (distal) for the test group and 0.2 mm ± 0.25 mm (mesial) and 0.3 mm ± 0.19 mm (distal) for the control group, p = .540 (mesial) and p = .462 (distal). Test group required half the chair time (127 ± 13 min) when compared to the control group (259 ± 15 min, p < .001).

CONCLUSIONS

Within the limits of this trial, both treatment protocols resulted in excellent esthetic outcomes with PES >12 after 1-year follow-up.