Efficacy of lateral bone augmentation prior to implant placement: A systematic review and meta-analysis

In vivo experimental study comparing alveolar ridge preservation versus guided bone regeneration after unassisted socket healing at intact and damaged sites in narrow alveolar ridges

BACKGROUND

To compare bone regeneration and dimensional alteration of alveolar ridge at intact and damaged extraction sockets after alveolar ridge preservation (ARP) and implant placement versus unassisted socket healing followed by guided bone regeneration (GBR) with simultaneous implant placement.

METHODS

In 6 beagle dogs, 3 types of extraction sockets in the mandible were created: (1) intact sockets, (2) 1-wall defect sockets and (3) 2-wall defect sockets. The sockets were allocated to undergo either (1) ARP and implant placement 8 weeks later (ARP group) or (2) GBR with simultaneous implant placement after 8 weeks of unassisted socket healing (GBR group). After an additional healing period of 8 weeks, bone regeneration and dimensional changes were evaluated radiographically and histologically.

RESULTS

GBR showed superior bone formation and greater bone gains compared to ARP, regardless of the initial extraction-socket configuration. Although ARP maintained the preexisting alveolar ridge dimensions, peri-implant bone defects were still detected at 8 weeks of follow-up. Histomorphometric analyses confirmed that GBR increased dimensions of the alveolar ridge compared to baseline, and the augmentation and bone regeneration were greater with GBR than with ARP.

CONCLUSION

Early implant placement with ARP can mitigate alveolar ridge changes in the narrow alveolar ridge. However, early implant placement with simultaneous GBR creates the conditions for enhanced bone regeneration around the implant and greater ridge augmentation compared to ARP, irrespective of the extraction-socket configuration.

Double layer graft technique for horizontal alveolar ridge augmentation with staged implant placement: radiographic histological and implant stability analysis-a case report

INTRODUCTION

Horizontal ridge augmentation of a deficient alveolar bone site is performed either simultaneously with implant placement or in a staged approach prior to implant insertion. There are several available strategies for the augmentation of alveolar ridge deficiencies, including guided bone regeneration (GBR) through the use of barrier membranes. The success of the GBR approach mainly depends on the exclusion of soft tissue cells during bone remodeling.

CASE PRESENTATION

A healthy 25-year-old male patient presented with a missing upper left central incisor after clinical and radiographic examination, the site showed a class III defect horizontal atrophy. The procedure performed was the horizontal alveolar ridge augmentation using resorbable pericardium membrane with double layer graft technique (DLT) where autogenous bone placed as a first layer of the graft followed by xenograft as a second layer, the membrane was fixed with titanium pins. A cone beam computed tomography (CBCT) was performed before, immediately and 6 month following the surgery. After 6 months during implant placement, a core biopsy specimen was retrieved, stored and prepared for histological evaluation, with assessment of primary implant stability. The radiographic analysis showed a horizontal width gain of about 4 mm, at 6 month following implant placement, the implant was successfully osteointegrated with stability assessment also done after 6 months from placement.

CONCLUSION

DLT was successfully used for horizontal alveolar ridge augmentation, thus allowing a prosthetically driven implant placement. More cases assessing implant survival and success are needed to confirm the results of this case report.

Lateral bone augmentation with a composite graft covered with a stretched and pinned collagen membrane: A retrospective case series using cone-beam computed tomography

AIMS

(1) To assess the effectiveness of the Sausage Technique™ when applied for lateral bone augmentation by multiple experienced clinicians; (2) To identify risk indicators for a poor outcome and to assess the need for adjunctive surgery.

MATERIALS AND METHODS

All patients who had been treated with the Sausage Technique™ for lateral bone augmentation by three experienced surgeons between January 2019 and December 2021 were included in a retrospective case series. The Sausage Technique™ technique includes the use of autogenous bone chips and deproteinized bovine bone mineral (1:1 ratio), covered with a stretched and pinned collagen membrane. The increase in alveolar width between the pre-operative situation and 9 months was assessed at different levels on superimposed cone-beam CT scans.

RESULTS

Twenty-five augmentations performed in 25 patients (17 males, 8 females, mean age 51 years) were available for evaluation. Mean alveolar width increased from 4.35 to 7.43 mm at 3 mm below the crest. The mean increase of 3.08 mm (95% CI 2.10-4.06; p < 0.001) was significant. The outcome of non-containing single implant sites was significantly worse than the outcome of other sites (MD 2.67 mm; p = 0.008). The need for regrafting was 4% and the need for soft tissue augmentation was 48%. Twenty percent of the patients needed soft tissue augmentation due to a lack of keratinized mucosa width, and 32% due to a lack of buccal convexity. The former was mainly needed at multiple implant sites, whereas the latter was mainly required at single implant sites. All implant survived and remained healthy until the final follow-up.

CONCLUSION

The Sausage Technique™ is an effective bone augmentation technique. Non-containing single implant sites were associated with a poor outcome and adjunctive soft tissue augmentation was needed in about half of the patients.

Bone alteration and esthetics associated with implant-supported prostheses in the anterior maxilla under different implant placement timing: A retrospective clinical study of 1 to 3 years

STATEMENT OF PROBLEM

Different factors influence alterations in facial bone thickness and esthetic outcomes after implant placement. Whether the timing of implant placement influences alterations in the bone dimensional and esthetic outcomes is unclear.

PURPOSE

The purpose of this retrospective clinical study was to assess the influence of the timing of implant placement on alveolar bone alterations and esthetic outcome.

MATERIAL AND METHODS

Data were collected from 40 patients who had received guided bone regeneration (GBR) performed simultaneously with immediate, early, or delayed single-tooth implant placement in the anterior maxilla. Facial and palatal horizontal bone thicknesses (FHBT, PHBT) and vertical bone level (FVBL, PVBL) immediately after surgery (T0), at 6 months after implant placement (T1), and at 1 to 3 years follow-up (T2) were measured, and the changes calculated. The pink esthetic score (PES) and white esthetic score (WES) were evaluated at the 1- to 3-year follow-up. The Kruskal-Wallis followed by the Dunn t test was applied to evaluate bone alteration among groups, and the Bonferroni method was used for adjusting multiple comparisons. The 1-way ANOVA test was used to determine any significance in the esthetic outcome in the 3 groups (α=.05).

RESULTS

The reduction in the FHBT0 of the immediate, early, and delayed implant placement group (T2-T0) was -1.17 (-1.70, -0.61) mm, -1.53 (-1.69, -0.49) mm, and -1.47 (-2.30, -0.20) mm, respectively. The FHBT around the implant apices remained basically stable. No obvious changes in the PHBT around the implants of the immediate and delayed implant placement group were noted. The FVBL significantly decreased in each group during the follow-up period (-1.34 (01.88, -0.56) mm, immediate; -2.88 (-3.79, -1.07) mm, early; -1.26 (-2.52, -0.48) mm, delayed). The PVBL change in the early implant placement group (-2.18 (-3.26, -0.86) mm) was more significant than that in the immediate (-0.55 (-2.10, -0.17) mm) and delayed (-0.51 (-1.29, 0.02) mm) implantation groups (P =.013). The mean ±standard deviation PES/WES score of the immediate (15.6 ±1.84) and early (15.00 ±1.13) implant placement groups was higher than that of the delayed implant placement group (13.92 ±2.10) without significant difference.

CONCLUSIONS

Similar bone changes and esthetic outcomes were found around implants of the immediate, early, and delayed implant placement groups.

Soybean Oil-Based 3D Printed Mesh Designed for Guided Bone Regeneration (GBR) in Oral Surgery

This study aims to obtain a cyto-compatible 3D printable bio-resin for the manufacturing of meshes designed from acquired real patients' bone defect to be used in future for guided bone regeneration (GBR), achieving the goal of personalized medicine, decreasing surgical, recovery time, and patient discomfort. To this purpose, a biobased, biocompatible, and photo-curable resin made of acrylated epoxidized soybean oil (AESO) diluted with soybean oil (SO) is developed and 3D printed using a commercial digital light processing (DLP) 3D printer. 3D printed samples show good thermal properties, allowing for thermally-based sterilization process and mechanical properties typical of crosslinked natural oils (i.e., E = 12 MPa, UTS = 1.5 MPa), suitable for the GBR application in the oral surgery. The AESO-SO bio-resin proves to be cytocompatible, allowing for fibroblast cells proliferation (viability at 72 h > 97%), without inducing severe inflammatory response when co-cultured with macrophages, as demonstrated by cytokine antibody arrays, that is anyway resolved in the first 24 h. Moreover, accelerated degradation tests prove that the bio-resin is biodegradable in hydrolytic environments.

Horizontal ridge augmentation using guided bone regeneration with an association of particulate allografts mixed with platelet-rich fibrin, collagen membrane and tent-screws: A prospective study

BACKGROUND

Guided Bone Regeneration (GBR) is a versatile technique employed not only to correct pre-implant alveolar bone defects but also to facilitate bone defect correction during simultaneous implant placement. The effectiveness of GBR varies significantly among different protocols, as reported in the literature. This study specifically aimed to radiologically evaluate the horizontal bone gain obtained using a GBR procedure combining a particulate allograft, platelet-rich fibrin, resorbable collagen membrane, and screw tents.

MATERIALS AND METHODS

A total of 42 patients with an insufficient alveolar bone width for dental implant placement were treated with a GBR technique using a mixture of particulate allograft (demineralised freeze-dried bone allograft 300-500 and 500-1000 µm), advanced platelet-rich fibrin (A-PRF), resorbable collagen membranes and screws tents (1.2 mm in diameter). Over the course of the study, a total of 63 GBR procedures were performed on these patients. Bone gains were measured by cone-beam computed tomography at 9.1 ± 2.0 months post-operative.

RESULTS

A significant mean increase (P < 0.001) of 3.2 ± 0.9 mm at the sites of the greatest bone defect was observed. This improvement was consistent across various locations, including both maxillary and mandibular regions, and in cases of terminal and embedded edentulism, without any post-operative complications during the entire post-operative follow-up. All patients benefited from implant placement following the bone augmentation protocol.

CONCLUSION

GBR combining particulate allografts, A-PRF, collagen membranes, and screw tents achieves reliable, predictable, and reproducible clinical gains that allow for future implant placement.

Alveolar ridge changes 1-year after early implant placement, with or without alveolar ridge preservation at single-implant sites in the aesthetic region: A secondary analysis of radiographic and profilometric outcomes from a randomized controlled trial

OBJECTIVES

To assess both the radiographic and profilometric outcomes of early implant placement with or without alveolar ridge preservation (ARP) (using two different ARP techniques) after 1 year of loading.

MATERIALS AND METHODS

Seventy-five patients with a failing single tooth in the anterior maxilla were randomly allocated to three groups (1:1:1): (a) ARP using demineralized bovine bone mineral containing 10% collagen (DBBM-C) covered by a collagen matrix (CM), (b) ARP using DBBM-C covered with a palatal graft (PG), and (c) unassisted socket healing (control). Eight weeks after tooth extraction, early implant placement was performed in all patients. Cone-beam computed tomography (CBCT) and impressions were taken 8 weeks after tooth extraction (ARP/unassisted healing) prior to implant placement and 1-year post-loading. Radiographic and profilometric outcomes were evaluated.

RESULTS

Out of the 70 patients available for re-examination at 1-year post-loading, 55 datasets could be assessed (ARP-CM 19; ARP-PG 17; Control 19). The need for additional guided bone regeneration (GBR) at implant placement amounted to 31.6% (ARP-CM), 29.4% (ARP-PG), and 68.4% (unassisted healing). Adjusted models revealed that residual buccal bone height and additional GBR at implant placement significantly influenced the magnitude of the alveolar changes at 1 year (p < 0.05). In patients with ARP (group ARP-CM or ARP-PG) without additional GBR, the presence of bone convexity amounted to 36.0% (9/25) at 1-year post-loading. For patients that received ARP and additional GBR at implant placement, the frequency of bone convexity increased to 72.7% (8/11) (p = 0.042). Regarding profilometric measurements, a tendency toward agreement with radiographic outcomes was observed.

CONCLUSIONS

Early implant placement with ARP can attenuate alveolar ridge changes at 1-year post loading by minimizing both radiographic and profilometric alterations. However, early implant placement with simultaneous GBR consistently yields superior radiographic and profilometric outcomes, regardless of whether ARP is performed.

Can jaw bone healed from chronic sclerosing osteomyelitis be considered healthy when planning dental implants? Case report with 20-year follow-up

Introduction and importance

Extraction of mandibular third molars can lead to complications such as chronic sclerosing osteomyelitis (CSO), an inflammatory bone marrow disease that tends to progress. CSO involves the cortical plates and often the periosteal tissues and is caused by a variety of microorganisms, including Corynebacterium spp. The treatment of chronic osteomyelitis (CO) and CSO remains challenging, as there is no universal treatment protocol. This case report investigated whether jaw bone that has healed from chronic sclerosing osteomyelitis can be considered healthy bone when planning dental implants.

Case presentation

A 21-year-old Caucasian woman developed CO and CSO after third molar surgery.

Clinical discussion

A combination of alveolar ridge bone resection, extraction of teeth 47-32, and long-term specific antibiotic therapy against Corynebacterium spp. was administered. An attempt at preprosthetic alveolar ridge reconstruction with an anterior superior iliac crest bone graft resulted in graft failure and the patient refused further harvesting procedures. Implantation in the intraforaminal zone also resulted in the loss of two implants after loading. Finally, inferior alveolar nerve transposition resulted in the successful reimplantation of two implants, which were fully functional almost 11 years later.

Conclusion

This case report presents the treatment history of this patient. With a longitudinal observation period of greater than 20 years, the results of this case demonstrate the successful treatment of bone with CO, CSO, and Corynebacterium spp. infection. Following the removal of infected bone, radical debridement, and long-term antibiotic therapy, bone health was restored.

Ridge augmentation planning, wound healing evaluation, and peri-implant tissue phenotype assessment with ultrasonography: A case report

BACKGROUND

Ridge regeneration for implant therapy requires comprehensive site evaluation and wound healing monitoring. This case report aimed to demonstrate ultrasound (US) can image soft and hard tissues for surgical planning and assess longitudinal outcomes.

METHODS AND RESULTS

US was used in a patient planned for ridge augmentation to evaluate soft tissue thickness, location of muscle attachment, and hard tissue defect features presurgically. US were obtained at 1, 2.5, and 5 months afterward to assess tissue healing. Preoperatively, US showed ∼2.5 mm and ∼0.8 mm soft tissue thickness on the facial and lingual sides, respectively. The crestal bone width was ∼2 mm, with severe facial bone deficiency and high muscle attachment. US showed wound approximation and ridge width gain to 4.5 and 4.0 mm at 1 and 5 months, respectively. US tissue perfusion increased to ∼two-fold and ∼4-fold at 1 and 2.5 months and reduced below the baseline at 5 months. An implant with simultaneous bone augmentation was performed accordingly. Tissue phenotype around the implant was measured on US images at 1-year visit.

CONCLUSIONS

This case report demonstrated that US parameters could be valuable for planning and wound healing outcome assessment of ridge augmentation in clinical as well as research settings.

KEY POINTS

Why is this case new information? Novel high-resolution, chairside ultrasound was proposed to facilitate treatment planning and wound healing outcome assessment of ridge augmentation in clinical as well as research settings. What are the keys to successful use of this technology? Proper training in imaging acquisition and interpretation Adhere to high-level disinfection protocol Patient education and explanation What are the primary limitations to success in using this technology? Investment in this technology Learning curve in imaging acquisition and reading Insurance reimbursement strategy.

Biological performance of a novel bovine hydroxyapatite in a guided bone regeneration model: A preclinical study in a mandibular defect in dogs

OBJECTIVES

This preclinical model study aims to evaluate the performance and safety of a novel hydroxyapatite biomaterial (Wishbone Hydroxyapatite, WHA) on guided bone regeneration compared to a commercially available deproteinized bovine bone mineral (Bio-Oss, BO).

MATERIAL AND METHODS

Twenty-four beagle dogs were allocated to three timepoint cohorts (4, 12, and 26 weeks) of eight animals each. In all animals, four critical-sized, independent wall mandibular defects were created (32 defects/cohort). Each animal received all four treatments, allocated randomly to separated defects: WHA + collagen membrane (M), BO + M, no treatment (Sham, Sh), and Sh + M. At each timepoint, the specimens were harvested for histologic and histomorphometric analyses to determine the newly formed bone and osteoconductivity.

RESULTS

At 4 weeks, bone regeneration was significantly higher for WHA + M (46.8%) when compared to BO + M (21.4%), Sh (15.1%), and Sh + M (23.1%) (p < 0.05); at 12 and 26 weeks, regeneration was similar for WHA and BO. Bone-to-material contact increased over time similarly for WHA + M and BO + M. From a safety point of view, inflammation attributed to WHA + M or BO + M was minimal; necrosis or fatty infiltrate was absent.

CONCLUSIONS

WHA + M resulted in higher bone regeneration rate than BO + M at 4 weeks. Both BO + M and WHA + M were more efficient than both Sh groups at all timepoints. Safety and biocompatibility of WHA was favorable and comparable to that of BO.

Evaluation of the Success of Autogenous Block Grafting in Atrophic Maxillary and Mandibular Ridges Prior to and After Implant Placement

BACKGROUND

Dental implantology's success relies on adequate bone volume and quality, necessitating bone augmentation for implant placement. Primary lateral bone augmentation, utilizing autogenous block grafts, addresses horizontal bone loss.

OBJECTIVE

This study aims to evaluate the efficacy of autogenous block grafting, specifically ramus and fibula blocks, in addressing severe atrophic ridges before and after implant placement.

METHODS

Twenty-one patients underwent block grafting, predominantly using the ramus technique (80/20 ratio). CBCT measurements assessed horizontal grafting outcomes. Implant success and bone volume changes were analyzed.

RESULTS

Post-grafting, bone width increased from 1.8-3.1 mm to 4.5-6 mm, exceeding critical thresholds. Implant success reached 95%, indicating the grafting techniques' effectiveness.

CONCLUSION

Autogenous block grafting, especially with ramus and fibula blocks, transforms severe atrophic ridges, enabling successful implant integration. Long-term follow-up is essential for a comprehensive evaluation.

CLINICAL RELEVANCE

This study provides crucial insights into autogenous block grafting's transformative impact on challenging cases, guiding future applications in reconstructive dentistry.

Clinical outcomes following atrophic alveolar ridge reconstruction using collagenated xenogeneic bone block or autogenous bone block: One-year follow-up of a randomized controlled clinical

AIM

This investigation aimed to evaluate the 1-year survival of implants placed after staged lateral alveolar ridge augmentation using equine-derived collagenated xenogeneic bone blocks (CXBBs) or autogenous bone block (ABB).

MATERIALS AND METHODS

Fifty patients who underwent lateral augmentation in a previous trial were included. The primary outcome measure was implant survival at the 1-year follow-up, and secondary outcomes included implant success, peri-implant clinical and volumetric parameters, pink aesthetic scores (PES) and patient-reported outcome measures. Data analysis involved Fisher's exact test, the Mann-Whitney U-test and the Wilcoxon signed-rank test.

RESULTS

In this study, no late implant failures were observed. The cumulative survival rates were 78.6% for the CXBB group and 90.9% for the ABB group, with no difference between the groups. Similarly, the success rates were 53.6% and 63.6%, respectively, showing no significant difference. Peri-implant clinical and volumetric parameters indicated the presence of healthy peri-implant tissues surrounding implants placed in both CXBB- and ABB-augmented sites. PES were 8.5 and 11.0 for implants placed in CXBB- and ABB-augmented sites, respectively. Furthermore, patient satisfaction rates were high and similar between the groups.

CONCLUSIONS

Dental implants placed in both CXBB- and ABB-augmented ridges demonstrated no statistically significant differences in clinical, volumetric and aesthetic outcomes, along with high patient satisfaction rates.

Vertical bone augmentation using collagenated or non-collagenated bone substitute materials with or without recombinant human bone morphogenetic protein-2 in a rabbit calvarial model

PURPOSE

The aim of this study was to determine 1) the bone-regenerative effect of porcine bone block materials with or without collagen matrix incorporation, 2) the effect of a collagen barrier, and 3) the effect of adding recombinant human bone morphogenetic protein-2 (rhBMP-2) to the experimental groups.

METHODS

Four treatment modalities were applied to rabbit calvaria: 1) deproteinized bovine bone mineral blocks (DBBM), 2) porcine bone blocks with collagen matrix incorporation (PBC), 3) porcine bone blocks alone without collagen matrix incorporation (PB), and 4) PBC blocks covered by a collagen membrane (PBC+M). The experiments were repeated with the addition of rhBMP-2. The animals were sacrificed after either 2 or 12 weeks of healing. Micro-computed tomography (micro-CT), histologic, and histomorphometric analyses were performed.

RESULTS

Micro-CT indicated adequate volume stability in all block materials. Histologically, the addition of rhBMP-2 increased the amount of newly formed bone (NB) in all the blocks. At 2 weeks, minimal differences were noted among the NB of groups with or without rhBMP-2. At 12 weeks, the PBC+M group with rhBMP-2 presented the greatest NB (P<0.05 vs. the DBBM group with rhBMP-2), and the PBC and PB groups had greater NB than the DBBM group (P>0.05 without rhBMP-2, P<0.05 with rhBMP-2).

CONCLUSIONS

The addition of rhBMP-2 enhanced NB formation in vertical augmentation using bone blocks, and a collagen barrier may augment the effect of rhBMP-2.

Digital Evaluation of Vertical Ridge Augmentation with the Modified Shell Technique Using a Xenogeneic Bone Lamina: A Case Series

Vertical ridge augmentation is a demanding and technique-sensitive surgical procedure. In the present case series, cone beam CT (CBCT) scans from the clinical routine of patients treated using a novel approach for vertical bone augmentation were assessed. All patients showed a single-tooth class 5 defect and were treated using a modification of the original shell technique. Cortical bone plates were replaced with a lamina composed of a partially demineralized porcine xenograft. CBCT scans of six consecutive patients were treated with the lamina and particulate bone from the mandibular ramus prior to a single tooth implant in the anterior maxilla were included. Pre- and postsurgical CBCT data sets were superimposed and analyzed digitally using surface matching and Boolean subtraction. The volume of the grafted area was calculated with and without the xenograft. The vertical gain of the ridge height measured in this case series varied from 7 to 11.3 mm. The mean vertical gain was 8.97 mm. The mean volume including the xenograft was 382.59 mm3 (SD 73.39) and 250.84 mm3 (SD 53.67) without the lamina. The modified shell technique used in this case series for the vertical augmentation of single-tooth class 5 defects provided sufficient bone for single implant restorations.

Comparative evidence of different surgical techniques for the management of vertical alveolar ridge defects in terms of complications and efficacy: A systematic review and network meta-analysis

AIM

To systematically appraise the available evidence on vertical ridge augmentation (VRA) techniques and estimate a treatment-based ranking on the incidence of complications as well as their clinical effectiveness.

MATERIALS AND METHODS

Searches were conducted in six databases to identify randomized clinical trials comparing VRA techniques up to November 2022. The incidence of complications (primary) and of early, major, surgical and intra-operative complications, vertical bone gain (VBG), marginal bone loss, need for additional grafting, implant success/survival, and patient-reported outcome measures (secondary) were chosen as outcomes. Direct and indirect effects and treatment ranking were estimated using Bayesian pair-wise and network meta-analysis (NMA) models.

RESULTS

Thirty-two trials (761 participants and 943 defects) were included. Five NMA models involving nine treatment groups were created: onlay, inlay, dense-polytetrafluoroethylene, expanded-polytetrafluoroethylene, titanium, resorbable membranes, distraction osteogenesis, tissue expansion and short implants. Compared with short implants, statistically significant higher odds ratios of healing complications were confirmed for all groups except those with resorbable membranes (odds ratio 5.4, 95% credible interval 0.92-29.14). The latter group, however, ranked last in clinical VBG.

CONCLUSIONS

VRA techniques achieving greater VBG are also associated with higher incidence of healing complications. Guided bone regeneration techniques using non-resorbable membranes yield the most favourable results in relation to VBG and complications.

Is alveolar ridge preservation an overtreatment?

The morphology and dimensions of the postextraction alveolar ridge are important for the surgical and restorative phases of implant treatment. Adequate new bone formation and preservation of alveolar ridge dimensions following extraction will facilitate installation of the implant in a restorative position, while preservation of soft tissue contour and volume is essential for an aesthetic and implant-supported restoration with healthy peri-implant tissues. Alveolar ridge preservation (ARP) refers to any procedure that aims to: (i) limit dimensional changes in the alveolar ridge after extraction facilitating implant placement without additional extensive bone and soft tissue augmentation procedures (ii) promote new bone formation in the healing alveolus, and (iii) promote soft tissue healing at the entrance of the alveolus and preserve the alveolar ridge contour. Although ARP is a clinically validated and safe approach, in certain clinical scenarios, the additional clinical benefit of ARP over unassisted socket healing has been debated and it appears that for some clinicians may represent an overtreatment. The aim of this critical review was to discuss the evidence pertaining to the four key objectives of ARP and to determine where ARP can lead to favorable outcomes when compared to unassisted socket healing.

Membrane barriers for guided bone regeneration: An overview of available biomaterials

Dental implants revolutionized the treatment options for restoring form, function, and esthetics when one or more teeth are missing. At sites of insufficient bone, guided bone regeneration (GBR) is performed either prior to or in conjunction with implant placement to achieve a three-dimensional prosthetic-driven implant position. To date, GBR is well documented, widely used, and constitutes a predictable and successful approach for lateral and vertical bone augmentation of atrophic ridges. Evidence suggests that the use of barrier membranes maintains the major biological principles of GBR. Since the material used to construct barrier membranes ultimately dictates its characteristics and its ability to maintain the biological principles of GBR, several materials have been used over time. This review, summarizes the evolution of barrier membranes, focusing on the characteristics, advantages, and disadvantages of available occlusive barrier membranes and presents results of updated meta-analyses focusing on the effects of these membranes on the overall outcome.

Clinical efficacy of guided bone regeneration in peri-implantitis defects. A network meta-analysis

Guided bone regeneration (GBR) at peri-implantitis-related bone defects involves the placement of bone-filler particles in the intrabony defects and the application of a barrier membrane. The efficacy of different GBR-supported reconstructive measures as well as their potential superiority compared to non-GBR-supported treatment strategies for bone defects at peri-implantitis sites, however, remains unclear. Therefore, this analysis was designed to evaluate the long-term (≥12 months) clinical efficacy of GBR-supported reconstructive surgical therapy for peri-implantitis-related bone defects. In terms of resolving inflammation, the implementation of GBR protocols applying xenogenic bone substitutes yielded a higher reduction of bleeding on probing and probing depth value compared to the GBR protocol applying autogenous bone. Furthermore, for the changes in bleeding on probing and probing depths, GBR approaches using xenogenic bone showed superiority over the non-GBR treatments. Xenogenic bone with or without a barrier membrane was associated with improved radiographic bone levels and less soft tissue recession compared to the use of a GBR protocol implementing autogenous bone. Nonetheless, when interpreting this findings, the limited number of available studies with low to serious risk of bias and the short follow-up periods limited to 12 months should be considered.

Dimensional changes after horizontal and vertical guided bone regeneration without membrane fixation using the retentive flap technique: A 1-year retrospective study

AIM

To evaluate the dimensional changes after horizontal and vertical guided bone regeneration (GBR) without membrane fixation using the retentive flap technique.

METHODS

This study retrospectively examined two cohorts that received vertical or horizontal ridge augmentations (VA or HA groups). GBR was performed using particulate bone substitutes and resorbable collagen membranes. The augmented sites were stabilized using the retentive flap technique without any additional membrane fixation. The augmented tissue dimensions were assessed using cone-beam computed tomography at preoperative, immediately postoperative (IP), 4 months (4M), and 1 year (1Y).

RESULTS

Postoperative vertical bone gain in 11 participants of VA group amounted to 5.96 ± 1.88 mm at IP, which decreased to 5.53 ± 1.62 at 4M and to 5.26 ± 1.52 mm at 1Y (intragroup p < 0.05). The horizontal bone gain at IP in 12 participants amounted to 3.98 ± 2.06 mm, which decreased to 3.02 ± 2.06 at 4M and to 2.48 ± 2.09 mm at 1Y (intragroup p < 0.05). The mean implant dehiscence defect height after 1Y was 0.19 ± 0.50 mm in the VA group, and 0.57 ± 0.93 mm in the HA group.

CONCLUSION

GBR without membrane fixation using the retentive flap technique seems to preserve the radiographic bone dimensions of vertically augmented sites. This technique may be less effective at preserving the width of the augmented tissue.

The importance of soft tissue condition in bone regenerative procedures to ensure long-term peri-implant health

Bone regenerative procedures have been widely proved to be a reliable treatment option to re-create the ideal pre-implant clinical conditions. Nevertheless, these techniques are not free from post-operative complications which might result in implant failure. Consequently, as demonstrated by the increasing recently published evidence, a careful pre- and intra-operative flap evaluation to ensure an ideal and hermetic tension-free wound closure is of paramount importance to successfully treat bony defects. In this respect, several surgical interventions mainly aimed to increase the amount of keratinized mucosa either to allow an optimal healing after a reconstructive procedure or to establish an optimal peri-implant soft tissue seal have been proposed. The present review summarizes the level of evidence on the surgical clinical aspects which have an impact on the soft tissue handling associated with bone reconstructive procedures and on the importance of soft tissue conditions to enhance and maintain peri-implant health in the long-term.

A conceptual review on reconstructive peri-implantitis therapy: Challenges and opportunities

OBJECTIVES

The current strategies to reconstruct lost peri-implant tissues due to the disease have been largely unpredictable. The aim of this conceptual review is to discuss relevant biological and biomechanical challenges of applying reconstructive means to treat peri-implantitis. Additionally, opportunities to improve treatment predictability are presented.

MATERIAL AND METHODS

A narrative review was conducted to fulfill the aim.

RESULTS

The four interrelated negative conditions hampering effective reconstruction are: inferior tissue perfusion, unfavorable bone topography, ineffective surface treatment, and unstable wound. First, peri-implant tissues resemble scars with reduced cellularity and vascularity, coupled with the absence of the periodontal ligament plexuses and the avascular implant and biomaterials, maintaining primary closure is a challenge, which is critical for regeneration. Second, defect morphology and bone topography surrounding implants determine the reconstructive potential. Unfortunately, noncontained defects are frequently encountered, with a combination of suprabony (horizontal bone loss) and infrabony (vertical usually involving circumferential bone loss) defects. Third, current attempts for implant surface decontamination are insufficient due to inaccessible macrostructure and rough surfaces in the micro-scale. Histologic evaluation has shown bacteria aggregation and calcified deposits around implants. Lastly, wound stability is difficult to achieve due to inherent soft tissue biomechanical quality and quantity deficiencies and mobile bone particulates. Opportunities to tackle the abovementioned challenges include the use of novel imaging technologies, such as high-frequency dental ultrasound and laser speckle imaging to evaluate tissue perfusion, soft tissue quality/quantity, and bone topography pre-surgically. The use of the operating microscope could allow better visualization and removal of etiologic factors. Strategies to improve soft tissue quality may include preoperative control of soft tissue inflammation and the potential use of biologics. Methods such as fixation to stabilize the biomaterials could be beneficial.

CONCLUSIONS

A more nuanced understanding of the current challenges and opportunities can lead to more effective preoperative and postoperative care protocols, ultimately improving the success rate of reconstructive procedures.

Barbell Technique: A Novel Approach for Bidirectional Bone Augmentation: Clinical and Tomographic Study

Horizontal bone augmentation is a common surgical procedure used in implant therapy to achieve adequate bone volume to permit dental implant placement. However, most current techniques are focused on unidirectional bone reconstruction (grafting only on the buccal side). This study was carried out to validate a new device that will permit bidirectional bone augmentation. Ten patients of both sexes (7 women and 3 men), with ages ranging from 29 to 62 years, who needed a bidirectional horizontal bone augmentation in maxilla were separated in accordance with the horizontal alveolar change (HAC) classification published by Pelegrine et al (2018). The patients classified as HAC 3 (ie, containing remaining cancellous bone at the recipient bed) received the Barbell device with xenogeneic biomaterial and a collagen membrane, whereas HAC 4 patients (ie, with no remaining cancellous bone at the recipient bed) received the Barbell device with a mixture of autogenous bone chips and xenogeneic biomaterial covered by a collagen membrane. For each patient, two computerized tomography scans were performed (T0 at baseline and T1 at 6 months postoperative examinations). Mean bone thickness (T0) in the studied sites were 3.25 ± 0.35 in HAC 3 and 1.98 ± 0.5 in HAC 4 patients. The mean bone thickness achieved after 6 months was 7.70 ± 0.89 mm and 8.62 ± 0.89 in HAC 3 and 4, respectively. All grafted sites were able to receive dental implants in adequate prosthetic positions. Based on these results, the use of this novel device permits bidirectional horizontal bone augmentation.

Radiographic outcomes of ridge reconstruction with autogenous bone block versus collagenated xenogeneic bone block: A randomized clinical trial

AIM

To compare, at different levels from the alveolar crest, the radiographic outcomes of equine-derived collagenated xenogeneic bone blocks (CXBB) and autogenous bone blocks (ABB) used for lateral alveolar ridge augmentation.

MATERIALS AND METHODS

Sixty-four patients with tooth gaps in atrophic alveolar ridges with ≤4 mm were randomly assigned to lateral augmentation using CXBB or ABB. The lateral bone thickness (LBT) was measured 2, 4, 6, 8, and 10 mm below the alveolar crest using CBCT scans obtained before augmentation surgery and at 30 weeks, prior to implant placement. Statistical analysis was performed using Shapiro-Wilk, Fisher's exact, Mann-Whitney, and Wilcoxon signed-rank tests.

RESULTS

Both CXBB and ABB resulted in significant total and buccal LBT gains at 2, 4, 6, 8, and 10 mm. LBT gains were similar between CXBB- and ABB-augmented sites, except for greater buccal LBT gains at 8 mm at CXBB-augmented sites. While ABB-augmented sites gained vertical bone height, CXBB-treated sites suffered vertical bone loss (CXBB: -0.16 mm; ABB: 0.38 mm, p < .0009).

CONCLUSIONS

CXBB and ABB were both associated with significant and similar LBT gains at 30 weeks.

Histopathological evaluation of the effect of melatonin gel on bone regeneration in rat model

Background

The purpose of this research was to investigate the effects of different doses of topical melatonin gel on bone regeneration in rat calvarial defects using histological analysis.

Materials and Methods

Fifteen adult female Wistar rats weighing approximately 200 g were used and 8 mm in diameter defects were created in their calvaria. The rats were divided into three groups: 1.2% melatonin gel, 5% melatonin gel, and the control group. The animals were sacrificed after 4 weeks. Hematoxylin and eosin staining were used to prepare histological sections. Statistical analysis was performed using the Analysis of variance and Tukey's post-hoc test. P < 0.05 was considered significant.

Results

The results showed a significant difference in rate of ossification (P < 0.001), area of new capillaries (P = 0.002), and mean degree of inflammation (P < 0.001) between the three groups. Comparing groups pairwise, degree of inflammation (P = 0.003) and area of new capillaries (P = 0.019) were significantly lower in the 5% melatonin gel group than the 1.2% melatonin gel group (P = 0.003). The percentage of ossification was substantially greater in the 5% melatonin gel group than in the control and 1.2% melatonin gel groups (P < 0.001).

Conclusion

Within the limitations of this animal study, our findings revealed that melatonin gel can be used as a stimulant of bone formation. Outcomes in this study show increased percentage of ossification in the melatonin groups when compared with the control, in a dose-dependent manner, as 5% melatonin gel has a greater effect on ossification.

Why is there a lack of evidence regarding errors and complications in periodontal and implant therapy?

The occurrence of errors, complications, and adverse effects may occur as a consequence of single or multiple events related to the clinician and/or patient. Apparently, the amount of dental literature on these undesirable outcomes has not been as prolific as that obtained for conventional primary periodontal outcome measures. This review explores the potential reasons for the lack of studies reporting on errors and complications in periodontal and implant therapy, as well as other noteworthy methodological aspects, to enlighten their impact on the selection of the best (or most appropriate) "gold standard" periodontal/implant-related treatment options, and on the overall decision-making process. The following points were addressed: (a) the importance of reporting errors and complications in clinical research; (b) the adequate reporting of errors and complications in periodontology and dental implantology; and (c) efficacy trials vs effectiveness studies and their impact on the assessment and report of periodontal and implant treatment-related risks and complications.

Individual "alveolar phenotype" limits dimensions of lateral bone augmentation

AIM

Alveolar ridge resorption following tooth extraction often renders a lateral bone augmentation inevitable. Some patients, however, suffer from severe early (during graft healing, E_res ) and/or late (during follow-up, L_res ) graft resorption. We explored the hypothesis that the "individual phenotypic dimensions" may partially explain the degree of such resorptions.

MATERIALS AND METHODS

Patients who underwent a guided bone regeneration (GBR) procedure were screened for inclusion according to the following criteria: (1) a relatively symmetrical maxillary arch; (2) an intact contra-lateral alveolar bone dimension; (3) the availability of a pre-operative cone-beam CT (CBCT); (4) a CBCT taken immediately after GBR, and (5) at least one CBCT scan ≥6 months after surgery. CBCT scans from different timepoints were registered and imported into the Mimics software (Materialise, Leuven, Belgium). Bone dimensions of the contra-lateral site of the augmentation, representing the "individual phenotypical dimension (IPD) of the alveolar crest", were superimposed on the augmented site and registered accordingly. As such, E_res and L_res could be measured over time, in relation to the IPD (in two dimensions; per millimetre apically from the alveolar crest, in the centre of the GBR), as well as in three dimensions (the entire GBR, 2 mm away from the mesial, distal, and apical border for standardization).

RESULTS

A total of 17 patients (23 augmented sites) were included. After E_res , the outline of the augmentation was in general located ±1 mm outside the IPD, but ≥1.5 years after GBR, it further moved towards the IPD (85% within 0.5 mm distance).

CONCLUSIONS

Within the limitations of this study, the results indicate that the dimensions of a lateral bone augmentation are defined by the "individual phenotypic bone boundaries" of the patient.

Customized Titanium Mesh for Guided Bone Regeneration in the Posterior Mandible in a Patient Previously Treated with Bisphosphonates

We describe the restorative treatment of an 86-year-old female patient who was referred to our specialist prosthodontics clinic. Due to secondary osteoporosis, she underwent oral antiresorptive therapy with ibandronic acid for 10 years. Although she was classified as a patient at increased risk of drug-induced osteonecrosis of the jaw, she eventually signed a consent form for fixed implant-supported prosthetic rehabilitation in her 4th sextant. However, after tooth extraction, the bone ridge was too small at the intended implant positions. Therefore, guided bone regeneration was performed with a computer-aided design/computer-aided manufacturing three-dimensional printed titanium mesh. Finally, a continuous augmented hard tissue ridge above 7 mm was found, and three implants were inserted. Eventually, after four months of submerged healing, the implants were loaded with single crowns. Now, the patient is seen regularly for supportive peri-implant therapy.

Informational content of two-dimensional panoramic radiographs and lateral cephalometric radiographs with respect to the bone volume of intraoral donor regions considering CBCT imaging

BACKGROUND

To test the hypothesis that cephalometric parameters in two-dimensional routine dental radiographs correlate with the bone volume of intraoral bone donor sites.

METHODS

One-hundred and eight radiographs [36 panoramic radiographs (PRs), 36 lateral cephalometric radiographs (LCRs), and 36 cone-beam computed tomography scans (CBCT)] of 36 patients (all three imaging techniques applied according to the needs of treatment planning), were analyzed individually. Cephalometric parameters (PR and LCR) were correlated with the bone volume measurement in three-dimensional CBCT scans in three intraoral donor sites (chin, mandibular retromolar region, and zygomatic alveolar crest).

RESULTS

The mean bone volumes measured for the chin were (3.10 ± 1.11 cm³ SD), the mandibular retromolar region (1.66 ± 0.54 cm³ SD), and the zygomatic alveolar crest (0.17 ± 0.04 cm³ SD). Cephalometric parameters were significantly correlated (all p-values < 0.05) with the bone volume in the chin and the mandibular retromolar region. The bone volume of the zygomatic alveolar crest exhibited no correlations (p > 0.05) with cephalometric parameters. However, it was significantly correlated (p < 0.01) with the mandibular retromolar bone volume. No gender-specific differences (p > 0.05) were observed concerning bone volumes in all bone harvesting regions. Nevertheless, the male population's interforaminal distance in the chin region was significantly higher (p = 0.001).

CONCLUSIONS

PRs and LCRs can be used at the initial stage of peri-implant augmentation planning to deduce conclusions about the bone volume in different intraoral bone donor sites. It can help describe indications and justify additional diagnostic options, such as three-dimensional radiologic techniques.

Customized 3D printed nanohydroxyapatite bone block grafts for implant sites: a case series

PATIENTS

A case series of 12 patients (mean age, 53.5 years) with horizontal ridge deficiencies had augmentations with customized 3D printed nanohydroxyapatite (3DHA) block grafts prior to implant placement. 3DHA graft materials were fabricated to fit the individual patient defects using DICOMs from CBCT images obtained from each patient. The CBCT images were then converted into the STL file format and 3DHA was reconstructed by 3D printing. Surgical bone augmentation consisted of 3DHA incorporating concentrated growth factors (CGFs) and platelet-rich fibrin (PRF) membrane. At 6 months, a bone biopsy and implantation were performed. The primary outcome was horizontal bone gain after 6 months. The secondary outcomes included information on the clinical outcomes, dimensions, and histomorphometric results.

DISCUSSION

The 3DHA block graft was successful in 10 of 12 patients. Graft adjustment was not required. All 3DHA adapted and fit well at all defect sites. Maximum mean horizontal bone gains were 3.06 ± 1.02 and 3.56 ± 0.23 mm from the DICOMs and STL data sets, respectively. The volume gain was 229.8 ± 82.96 mm³. A low pain score after surgery was reported of 1.41 ± 0.51, while the healing index score increased with a maximum mean of 4.7 ± 0.67. Thirteen implants were placed with good primary stability (ISQ = 65 ± 4.08), without additional guided bone regeneration. Histomorphometric analysis revealed that new bone formation, bone tissue, residual grafts, and connective tissue were 28.6 ± 1.88, 30.48 ± 4.81, 19.82 ± 4.07, and 20.81 ± 4.41%, respectively.

CONCLUSIONS

A customized 3DHA block graft is a viable treatment option for primary implant-site augmentation.

Autogenous Bone Block versus Collagenated Xenogeneic Bone Block in the reconstruction of the atrophic alveolar ridge: a non-inferiority randomized clinical trial

OBJECTIVE

To compare the efficacy of equine derived collagenated bone blocks (CXBB) and autogenous bone block (ABB) for lateral alveolar ridge augmentation and two-stage implant placement.

MATERIALS AND METHODS

Sixty-four patients with tooth gaps up to 4 teeth and atrophic alveolar ridges with ≤ 4 mm were randomly assigned to lateral augmentation using CXBB or ABB. Lateral bone thickness was measured 2 mm below the alveolar crest at augmentation surgery and 30 weeks later at implant placement. Implant related outcomes, adverse events, surgery duration, pain sensation, analgesic consumption and oral health-related quality of life were also assessed. Data was analyzed using Fisher's exact, Mann-Whitney, and Wilcoxon signed-rank tests.

RESULTS

At 30 weeks, the median change in lateral bone thickness amounted to 2.90 (CXBB) and 3.00 (ABB), respectively. Secondary endpoints demonstrated similar results for CXBB and ABB in terms of possibility to place an implant, need to perform a secondary bone augmentation at implant placement and rate of complications. Early implant failure was 20% for CXBB and 10% for ABB, with no difference between the groups. Pain scores and postoperative consumption of analgesics were significantly lower in the CXBB group than in the ABB group, especially during the first days post-surgery.

CONCLUSION

CXBB is non-inferior to ABB for horizontal alveolar ridge augmentation and two-stage implant placement. This article is protected by copyright. All rights reserved.

Bone preservation or augmentation simultaneous with or prior to dental implant placement: A systematic review of outcomes and outcome measures used in clinical trials in the last 10 years

AIM

To evaluate outcome measures and methods of assessment in clinical studies on bone augmentation/preservation procedures for the placement of dental implants.

MATERIALS AND METHODS

A systematic search was performed on three databases from January 2011 to April 2021 to identify clinical studies reporting on any type of bone augmentation/preservation procedure. The outcomes that have been used to assess efficacy or performance in each study were registered and assigned to different domains (group of outcomes). The review followed the Preferred Reporting Items for Systematic Review and Meta-Analyses statement.

RESULTS

Seven-hundred and eighty-three publications were included. Only 81.8% of the papers had a clear definition of their primary outcome. The rate of complications (59.3%), implant survival (58.2%), 3D radiographic bone gain/change (30%), marginal bone level (MBL; 29%), and histological outcomes (25.5%) were the most frequently reported outcome domains. The most commonly used primary outcome was 3D radiographic bone gain/change (25.8%), followed by implant survival (13.0%). Patient-reported outcome measures (PROMs) were reported in 15.7% of studies. Differences in the reported outcomes were observed among different types of bone preservation/augmentation interventions (i.e., alveolar ridge preservation, immediate implants, horizontal and/or vertical ridge augmentation, and sinus floor augmentation).

CONCLUSION

Within the past decade, great heterogeneity was observed among the outcomes considered in studies evaluating bone preservation/augmentation procedures. Three-dimensional radiographic bone gain/change was the most routinely reported main outcome variable, while PROMs were rarely reported.

Effect of collagen membrane fixation on ridge volume stability and new bone formation following guided bone regeneration

AIM

To test the effect of membrane fixation on ridge volume stability and new bone formation using guided bone regeneration.

MATERIALS AND METHODS

In eight beagle dogs, after bilateral extraction of the maxillary pre-molars, a box-shaped defect was created on each side. All defect sites were augmented with a particulate bone substitute material, covered with either one of two non-cross-linked collagen membranes (CM1 or CM2) with or without fixation (-F or -UF). Samples were collected after 8 weeks. Histomorphometric and micro-computed tomography analyses were performed.

RESULTS

Membrane fixation made no significant difference to the total augmented volume for both membranes (p > .05). Histological data indicated that at the ridge crest the augmented tissue width amounted to 2.4 ± 0.4 mm in the group CM1-F and 2.4 ± 0.5 mm in the group CM1-UF, with no significant difference between the groups. Conversely, in CM2-F the augmented tissue width was significantly larger than in CM2-UF (2.3 ± 0.1 vs. 1.57 ± 0.27, p < .05).

CONCLUSIONS

Membrane fixation in contained defects failed to improve ridge volume stability regardless of the membrane type. However, it may enhance the width of the augmented ridge at the coronal portion depending on the type of membrane.

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.

Horizontal augmentation techniques in the mandible: a systematic review

Purpose

Placement of dental implants has evolved to be an advantageous treatment option for rehabilitation of the fully or partially edentulous mandible. In case of extensive horizontal bone resorption, the bone volume needs to be augmented prior to or during implant placement in order to obtain dental rehabilitation and maximize implant survival and success.

Methods

Our aim was to systematically review the available data on lateral augmentation techniques in the horizontally compromised mandible considering all grafting protocols using xenogeneic, synthetic, or allogeneic material. A computerized and manual literature search was performed for clinical studies (published January 1995 to March 2021).

Results

Eight studies ultimately met the inclusion criteria comprising a total of 276 procedures of xenogeneic, allogeneic, or autogenous bone graft applications in horizontal ridge defects. Particulate materials as well as bone blocks were used as grafts with a mean follow-up of 26.0 months across all included studies. Outcome measures, approaches and materials varied from study to study. A gain of horizontal bone width of the mandible with a mean of 4.8 mm was observed in seven of eight studies. All but one study, reported low bone graft failure rates of 4.4% in average.

Conclusions

Only limited data are available on the impact of different horizontal augmentation strategies in the mandible. The results show outcomes for xenogeneic as well as autologous bone materials for horizontal ridge augmentation of the lower jaw. The use of allogeneic bone-block grafts in combination with resorbable barrier membranes must be re-evaluated. Randomized controlled clinical trials are largely missing.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40729-022-00421-7.

Tooth as graft material: Histologic study

Background

An effective regenerative protocol is key to reestablish and maintain the hard and soft tissue dimensions over time. The choice of the graft material and its properties also could have an impact on the results. To prevent alveolar ridge dimensional changes, since numerous graft materials have been suggested and in the past years, a growing interest in teeth material has been observed as a valuable alternative to synthetic biomaterials.

Aim

The aim of the study was to explore the histomorphometric outcomes of tooth derivative materials as used as bone substitute material in socket preservation procedure.

Methods

After alveolar socket preservation (ASP) procedures using autologous demineralized tooth as graft material prepared by means of an innovative device, was evaluated. A total of 101 histological samples, from 96 subjects, were analyzed by evaluating the total amount of bone (BV), residual tooth material (residual graft, TT), and vital bone (VB). The section from each sample was then split in nine subsections, resulting in 909 subsections, to allow statistical comparison between the different areas.

Results

It was not noticed a statistically significant difference between maxillary and mandibular sites, being the amount of VB in upper jaw sites 37.9 ± 21.9% and 38.0 ± 22.0% in lower jaw sites and the amount of TT was 7.7 ± 12.2% in maxilla and 7.0 ± 11.1% in mandibles. None of the other considered parameters, including defect type and section position, were statistically correlated to the results of the histomorphometric analysis.

Conclusions

ASP procedure using demineralized autologous tooth‐derived biomaterial may be a predictable procedure to produce new vital bone potentially capable to support dental implant rehabilitation.

Estimation of Soft and Hard Tissue Revolutionization Surrounding Dental Implant: A 2-Year Retrospective Study

A dental implant is an idyllic mode of operandi for oral rehabilitation for complete and partially edentulous patients. The success of an implant is based on the health of its surrounding tissues. Therefore, the biological and clinical aspects of implant prosthesis and their surrounding tissues must persist to be investigated. A two-year retrospective clinical-radiological study was conducted to estimate peri-implant soft and hard tissue revolutionization after the placement of implants. A clinical-radiological investigation was carried out to determine the amount of soft and hard tissue revolutionization that occurred following the implantation of 200 implants. From October 2020 to March 2021, the research was carried out in the College of Dentistry at King Khalid University in Saudi Arabia. It was decided to conduct this study using a retrospective clinical record, which involved gathering information about patients who had previously received dental implants within the previous two years. Plaque index (PI), gingival index (GI), bleeding index (BI), peri-implant probing depth (PD), and peri-implant crestal bone level were measured at baseline and three months after implant placement in adult patients ranging in age from 20 to 50 years. The results were compared to the full-mouth index (FMI). Ethical clearance and written informed consent were obtained from all the study participants. The statistical analysis was done by using Statistical Package for Social Sciences (SPSS-23.0 version) (IBM; Chicago). The present study concluded that plaque accumulation, gingival bleeding, and probing depth were increased around implants during the follow-up, but it would not affect crestal bone loss. Still, it is essential to conduct a similar study with a larger sample size and a long follow-up period to give more precise results.

Preoperative buccal bone volume predicts long-term graft retention following augmentation in the esthetic zone: a retrospective case series

Objectives

Buccal bone augmentation in the esthetic zone is routinely used to achieve optimal clinical outcomes. Nonetheless, long‐term data are sparse, and it is unknown how baseline buccal bone volume affects the retention of the augmented volume over time.

Material and methods

This is a long‐term follow‐up retrospective case series. After a preoperative computed tomography scan, implants were placed in the anterior maxilla following guided bone regeneration, autogenous block grafting, or both. At the follow‐up, patients received a computed tomography scan and a clinical examination. Buccal bone volume was the primary outcome. Buccal bone thickness, peri‐implant, and esthetic parameters were secondary outcomes.

Results

After a median follow‐up of 6.7 years (interquartile range: 4.9–9.4), 28 implants in 19 patients (median age at augmentation: 43.3 years, interquartile range: 34.4–56.7, 53% female) were followed up. Preoperative buccal bone volume at baseline (V₀) showed a moderate correlation to final buccal bone volume (V_t, r_s = .43) but a strong correlation to the absolute volumetric change (ΔV = V_t–V₀, r_s = −.80). A linear mixed model for V_t had a large intercept of 91.39 (p < .001) and a rather small slope of .11 for V₀ (p = .11). Observed differences between treatments were not statistically significant in the mixed model. V₀ above 105 mm³ predicted a negative volume change (ΔV < 0) with a specificity of 100% and a sensitivity of 96%.

Conclusions

The results suggest higher gains in sites with lower V₀ and point to a cutoff V₀ above which the augmented volume is not retained long‐term.

Horizontal guided bone regeneration on knife-edge ridges: A retrospective case-control pilot study comparing two surgical techniques

INTRODUCTION

Studies evaluating guided bone regeneration (GBR) on knife-edge ridges using absorbable membranes with staged approaches have reported various horizontal bone gains. This study compared the horizontal bone gain obtained via a conventional technique of GBR and a recently-reported technique. Bone loss during the healing process was also measured.

METHODS

Consecutive patients who underwent GBR on knife-edge ridges via a conventional technique (control group) or the Sausage Technique (test group) were included in this study. GBR was performed using a collagen membrane and deproteinized bovine bone mineral combined with an autogenous graft at a 1:1 ratio. Cone-beam computed tomography (CBCT) was performed preoperatively, postoperatively, and after the patient healed. Horizontal bone width was measured on CBCT images 2 mm apical from the top of the crest. The preoperative CBCT and posthealing CBCT were superimposed to calculate the bone gain after healing, and the preoperative and postoperative CBCT scans were superimposed to calculate the bone gain after surgery. Bone loss during healing was calculated by subtracting the width of the ridge after healing from the postoperative width.

RESULTS

The mean horizontal bone gain was significantly lower in the control group (2.7 ± 1.8 mm; 83.2%) than in the test group (5.3 ± 2.3 mm; 216.8%) (p = 0.003). The average horizontal bone loss between regeneration and implant placement was 0.9 mm in the control group (27.9%) and 2.1 mm in the test group (29.4%). While the absolute bone loss was significantly different (p = 0.012), the percentage of bone resorption was not (p = 0.608).

CONCLUSION

The new technique resulted in significantly more bone gain than a conventional GBR technique. The rate of graft resorption during healing was stable regardless of the amount of grafted material.

It is all about peri-implant tissue health

Healthy peri-implant tissues have become synonymous with implant success and a major challenge in contemporary implant dentistry. Numerous local and systemic factors, as well as iatrogenic and other hitherto underappreciated factors of potential clinical relevance may influence the outcome of implant therapy. In this volume of Periodontology 2000, a group of outstanding experts has elaborated on the latest insights on the prevention and management of major surgical, biological and technical complications, to facilitate the establishment and maintenance of peri-implant health. This volume focusses on factors affecting early and late implant loss and the potential role of systemic diseases and local conditions. It comprehensively discusses the implementation of guided implant surgery to facilitate the cleansibility of implant-supported restorations, as well as iatrogenic factors related to bone augmentation/sinus grafting procedures. The challenges associated with soft-tissue grafting and the prevention of esthetic complications are also reviewed as the paradigm of success in implant dentistry shifts from implant survival towards a greater focus on patient-reported outcomes. Prosthetic failures remain a significant challenge and are discussed in light of new evidence, as is the relevance of the structural dimensions of the peri-implant mucosa. The volume closes with detailed and well-illustrated appraisals of the surgical management of peri-implantitis, the management and sequelae of dental implant removal, and the latest evidence for the oral health related quality of life in patients treated with dental implants.

Healing complications and their detrimental effects on bone gain in vertical-guided bone regeneration: A systematic review and meta-analysis

PURPOSE

Guided bone regeneration (GBR) utilizes a barrier membrane to allow osteogenic cells to populate a space by excluding epithelial and connective tissue cells. The purpose of this systematic review was to investigate the ratio of means (RoM) of vertical bone gained (Outcome) in vertical GBR procedures with healing complications (Intervention) and in vertical GBR procedures without healing complications (Comparison) in patients with vertically resorbed edentulous ridges that require dental implant placement (Population). A further aim was to investigate the incidence of complications after vertical GBR, and the influence of the timing of implant placement and regenerative devices on complications.

MATERIALS AND METHODS

MEDLINE (through PubMed), EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) were searched in duplicate up to, and including, November 2020 for randomized and controlled clinical trials and prospective and retrospective case series. Outcomes included patient-level and site-level RoM of vertical bone gain between healing complications and uneventful healing, and incidences of complications that occurred after vertical GBR. Random-effects and fixed-effects meta-analyses were performed where appropriate. This study was registered on PROSPERO (CRD42021226432).

RESULTS

A total of 31 publications were selected for the qualitative and quantitative analyses. The RoM of vertical bone gained was 0.65 [95% CI = 0.47, 0.91] and 0.62 [95% CI = 0.45, 0.85] when membrane exposure without suppuration and abscess formation without membrane exposure occurred respectively, in comparison to uneventful healing. The overall incidence proportion of healing complications occurring at the augmented site at a site- and patient-level was 11.0% [95% CI = 7.0, 15.6] and 10.8% [95% CI = 6.6, 15.7]. At a patient-level, there were no significant differences between a simultaneous or staged approach, or with the regenerative device used. The site-level incidence proportion of membrane exposure without suppuration, membrane exposure with suppuration, and with abscess formation without membrane exposure was 8.7% [95% CI = 4.2, 14.2], 0.7% [95% CI = 0.0, 2.9], and 0.5% [95% CI = 0.0, 1.7], respectively. The site-level weighted mean incidence proportion of neurologic complications occurring at the donor site was 0.8% [95% CI = 0.0, 5.3].

CONCLUSIONS

There is a significant reduction in bone gain when healing complications occur. However, healing complications are relatively uncommon surgical complications after vertical GBR.

Lateral Alveolar Ridge Augmentation with an Autogenous Bone Block Graft Alone with or without Barrier Membrane Coverage: a Systematic Review and Meta-Analysis

Objectives

To test the hypothesis of no difference in implant treatment outcome following lateral alveolar ridge augmentation with autogenous bone block graft with or without barrier membrane coverage.

Material and Methods

PubMed (MEDLINE), Embase and Cochrane library search in combination with a hand-search of relevant journals was conducted. Human studies published in English until the 8^th of February 2021 were included. Randomised controlled trials with an observation period longer than three months were included. Survival of implants and suprastructures were considered as primary outcomes measures, whereas peri-implant marginal bone loss, dimensional changes of the alveolar ridge, bone regeneration, patient-reported outcome measures, biological and mechanical complications were secondary outcome measures, as evaluated by descriptive statistics and meta-analysis including 95% confidence interval (CI).

Results

Electronic search and hand-searching resulted in 411 entries. Five randomised controlled trials characterised by low or high risk of bias fulfilled inclusion criteria. No statistically significant difference between the two treatment modalities was observed in any of the outcome measures. However, barrier membrane coverage was associated with a non-significant gain in alveolar ridge width of 0.5 mm (95% CI = -0.1 to 1.1) and diminished resorption of -0.9 mm (95% CI = -2.4 to 0.7) compared with no barrier membrane coverage.

Conclusions

Comparable implant treatment outcomes were revealed following lateral alveolar ridge augmentation with autogenous bone block graft alone with or without barrier membrane coverage. However, postoperative dimensional changes of the augmented seems to be diminished with the use of barrier membrane coverage as evaluated by two-dimensional linear measurements.

Lateral alveolar ridge augmentation using an equine-derived collagen-containing bone block: A prospective case series

OBJECTIVES

To assess the clinical performance of an equine-derived collagen-containing bone block (CXBB) for lateral alveolar ridge augmentation and staged implant placement.

MATERIAL AND METHODS

A total of n = 16 patients (16 implants) had received a modified surgical protocol for lateral ridge augmentation using a size-adapted rigidly fixed CXBB and contour augmentation. After 26 weeks of submerged healing, the primary endpoint was defined as the final ridge width (RW26) sufficient to place an adequately dimensioned titanium implant at the respective sites. Secondary outcomes included the gain in ridge width (RWg) and the need for secondary grafting. Clinical outcomes (bleeding on probing-BOP, probing depth-PD, and mucosal recession-MR) were assessed at implant loading and after a median observation period of 12.3 months.

RESULTS

In all patients (n = 16) investigated, RW26 allowed for a successful placement of an adequately dimensioned titanium implant at respective sites exhibiting mean RWg values of 5.09 ± 1.07 mm. A soft tissue dehiscence was noted in one patient (6.3%), and a secondary grafting was needed in two patients (12.5%) The changes in mean BOP, PD, and MR values at V9 amounted to 10.23 ± 30.11%, 0.14 ± 0.80 mm, and -0.01 ± 0.04 mm, respectively.

CONCLUSIONS

CXBB may represent a feasible approach for lateral alveolar ridge augmentation and two-stage implant placement.

Influence of soft tissue augmentation procedures around dental implants on marginal bone level changes-A systematic review

OBJECTIVES

This systematic review assessed the influence of soft tissue augmentation procedures on marginal bone level changes in partial or fully edentulous patients.

MATERIAL AND METHODS

We identified three relevant PICO questions related to soft tissue augmentation procedures and conducted a systematic search of four major electronic databases for clinical studies in systemically healthy patients receiving at least one dental implant and a minimum follow-up of one year after implant placement. The primary outcome was mean difference in marginal bone levels, and secondary outcomes were clinical and patient-related outcomes such as thickness of peri-implant mucosa, bleeding indices, and Pink Esthetic Score.

RESULTS

We identified 20 publications reporting on 16 relevant comparisons. Studies varied considerably and thus only two meta-analyses could be performed. This systematic review showed that: Soft tissue augmentation either for augmentation of keratinized mucosa or soft tissue volume inconsistently had an effect on marginal bone level changes when compared to no soft tissue augmentation, but consistently improved secondary outcomes. The combination soft and hard tissue augmentation showed no statistically significant difference in terms of marginal bone level changes when compared to hard tissue augmentation alone, but resulted in less marginal soft tissue recession as shown by a meta-analysis. Soft or hard tissue augmentation performed as contour augmentations resulted in comparable marginal bone level changes.

CONCLUSIONS

Peri-implant soft and hard tissues seem to have a bidirectional relationship: "Bone stands hard, but soft tissue is the guard".

Primary bone augmentation leads to equally stable marginal tissue conditions comparing the use of xenograft blocks infused with BMP-2 and autogenous bone blocks: A 3D analysis after 3 years

Objectives

To test whether or not primary bone augmentation using xenograft blocks infused with BMP‐2 or autogenous bone blocks lead to similar results regarding the implant survival and 3D marginal soft tissue contours.

Methods

Twenty‐four patients with an insufficient ridge width for implant placement in need of primary augmentation were randomly assigned to either a block of deproteinized bovine bone mineral infused with rhBMP‐2 (BMP) or an intraorally harvested block of autogenous bone (ABB). At 4 months, 1–4 dental implants were placed in the regenerated area. After crown insertion and at 3 years, peri‐implant tissue parameters, two‐ and three‐dimensional radiographic parameters, and soft tissue contour changes were evaluated. Explorative mixed model analyses were performed. The level of significance was set at 5%.

Results

At the 3‐year follow‐up, 23 patients with 40 implants were evaluated. The implant survival rate was 100% in both groups. At baseline, the marginal hard tissue levels amounted to −0.4 ± 0.8 mm (mean ± standard deviation) in the BMP group and −0.7 ± 1.0 mm in the ABB group. At 3 years, these values were −0.2 ± 0.4 mm (BMP) and −0.6 ± 1.0 mm (ABB). At baseline, the thickness of the buccal hard tissue at the level of the implant shoulder measured 1.1 ± 1.1 mm (BMP) and 1.4 ± 1.0 mm (ABB). At 3 years, it measured 0.9 ± 0.9 mm (BMP) and 0.7 ± 0.6 mm (ABB).

Conclusions

The present study demonstrated excellent implant survival rates and stable marginal hard tissue levels in both augmentation groups, 3 years after crown insertion. In addition, the clinical stability of soft and hard tissues was demonstrated in both groups.

Three-dimensional (3D) facially driven workflow for anterior ridge defect evaluation: a treatment concept

The esthetic rehabilitation of anterior ridge defects and the achievement of patient satisfaction has become major clinical challenges for dentists and technicians. Poor diagnosis and treatment planning are frequently associated with multiple surgical procedures which fail to meet patient expectations. The loss of hard and soft tissues in esthetic compromised zone is commonly associated with anterior ridges and affects the rehabilitation prognosis. The presence of interdental papilla and papillary configuration play a decisive role in patient satisfaction. A treatment planning considering esthetic parameters, prosthetic needs, and morphological defects must be conducted to improve treatment outcomes. Therefore, this study aims to propose a treatment concept for anterior ridge defects focusing on digital evaluation systems and guided by an ideal facially driven smile design project. In addition, the relevance of the papilla for the esthetic outcomes and the treatment alternatives for anterior ridge defects are also addressed.

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

BACKGROUND

The aim of this study was to examine osseous changes following lateral bone augmentation using a novel Ossix Volumax (OV) scaffold alone and compare it to combination therapy using freeze-dried bone allograft (FDBA) and resorbable collagen membrane (FDBA/CM).

METHODS

Thirty patients completed this 9-months prospective two-center cohort clinical trial. Before surgery and 9-months re-entry, linear measurements were performed, and impressions taken. Cone-beam computed tomography (CBCT) were done at baseline and 9 months. DICOM slice data were converted into volumetric images using 3D Slicer. Following 3D volumetric image construction, pre- and post-op Standard Triangle Language files were superimposed and volumetric data were extracted for a 10-mm region of interest. Linear measurements were compared similarly.

RESULTS

Baseline clinical parameters were similar in both groups (4.22 and 4.53 mm for OV and FDBA/CM at -2 mm, respectively). Following treatment, vertical distance from the stent had changed minimally (-0.36 and -0.12 mm, respectively). Similarly, lateral bone gain ranged from 0 to 0.4 mm, for both groups. To the contrary, the CBCT measurements showed a significantly greater increase in horizontal width in the control at -2 mm (0.95 ± 0.2 mm) compared with -0.62 mm for the OV (P = 0.000). Similar changes were observed at -5 mm (0.63 and -0.41 mm, respectively, P = 0.01). Sites volume had increased from 266 ± 149 mm³ to 360 ± 138 mm³ (P = 0.001) for FDBA/CM with negligible changes for OV (from 334 to 335 mm³ , P = 0.952). these between-group changes being statistically significant (P = 0.023).

CONCLUSION

FDBA/CM yielded better albeit moderate increase in the volume of the edentulous ridge, while OV scaffolds failed to produce similar results.

Biology of sinus floor augmentation with an autograft versus a bone graft substitute in a preclinical in vivo experimental model

OBJECTIVES

Compared to autografts, bone graft substitutes are slower to consolidate. If we understood why, this might open strategies to accelerate new bone formation and thus shorten the time to implant placement. In this study, we aimed at comparing autologous bone graft with a bovine bone graft substitute in a preclinical sinus lift model.

MATERIALS AND METHODS

The mouse posterior paranasal sinus served as a recipient site for grafting. Autograft from the oral cavity was compared against bone graft substitute using molecular, cellular, and histological analyses conducted on post-grafting days (PSD) 0, 9, 18, and 120.

RESULTS

Either autografts or bone graft substitutes were positioned on the sinus floor and remained in situ throughout the study. At the time of grafting and until day 9, bone graft substitutes were devoid of cells and alkaline phosphatase (ALP) activity while autografts were comprised of viable cells and showed strong ALP (mineralization) activity. Consequently, new bone formed faster in autografts compared to bone graft substitutes (140.21 ± 41.21 µm vs. 41.70 ± 10.09 µm, respectively, PSD9, p = .0143). By PSD18, osteogenesis was evident in autografted and xenografted sites. Osteoclasts identified by tartrate resistant acid phosphatase attached to, but did not resorb the bone graft substitute matrix. Autograft matrix, however, underwent extensive resorption. Transgenic mice revealed that Wnt-responsive osteoprogenitor cells originated primarily from the internal periosteum of the maxillary bone, and not from the Schneiderian membrane.

CONCLUSION

Autografts produce new bone sooner, but bovine bone graft substitutes eventually consolidate and then resist resorption. Enhancing osteoprogenitor cell recruitment to a bone graft substitute constitutes a viable strategy for accelerating bone formation in a sinus lift procedure.

Effectiveness of xenogeneic and synthetic bone-block substitute materials with/without recombinant human bone morphogenetic protein-2: A preclinical study using a rabbit calvarium model

AIM

To investigate new bone (NB) formation by using bone-block substitute materials with/without recombinant human bone morphogenetic protein-2 (rhBMP-2).

MATERIALS AND METHODS

Three synthetic bone-block substitute materials [biphasic calcium phosphate (BCP); nanostructured hydroxyapatite (NH); 3D-printed tricalcium phosphate/hydroxyapatite (3DP)] and one xenogeneic deproteinized bovine bone mineral (DBBM) block substitute were affixed to rabbit calvarium using osteosynthesis screws, either with rhBMP-2 (n = 12) or without rhBMP-2 (n = 16). At 2 or 12 weeks (n = 6 with rhBMP-2 and n = 8 without rhBMP-2 for each week), histologic, histomorphometric and microcomputed tomography analyses were performed.

RESULTS

The application of rhBMP-2 increased NB formation in all experimental groups at both weeks. DBBM resulted in a greater area of NB compared with synthetic blocks either with or without rhBMP-2 at 2 weeks (2.8 ± 0.9 vs. 1.4 ± 0.5-1.9 ± 1.4 mm² ; 1.4 ± 1.0 vs. 0.6 ± 0.3-0.9 ± 0.5 mm² ) and without rhBMP-2 at 12 weeks (3.0 ± 0.8 vs. 1.7 ± 0.7-2.6 ± 1.5 mm² ) (p > 0.05). NB formation did not differ significantly for DBBM and the three types of synthetic block with rhBMP-2 at 12 weeks (4.5 ± 2.0 vs. 3.8 ± 0.7-5.1 ± 1.1 mm² ; p > 0.05).

CONCLUSIONS

rhBMP-2 enhanced NB in all blocks. DBBM blocks yielded more NB than synthetic blocks without rhBMP-2. The application of rhBMP-2 appears to compensate for differences in late healing.

Ibero-Panamerican Federation of Periodontics Delphi study on the trends in diagnosis and treatment of peri-implant diseases and conditions: A Latin American consensus

BACKGROUND

The social diversity, heterogeneous culture, and inherent economic inequality factors in Latin America (LA) justify conducting a comprehensive analysis on the current status and future trends of peri-implant diseases and conditions. Thus, the aim of this Delphi study was to predict the future trends in the diagnosis and treatment of peri-implant diseases and conditions in LA countries for the year 2030.

METHODS

A Latin American steering committee and group of experts in implant dentistry validated a questionnaire including 64 questions divided into eight sections. The questionnaire was run twice with an interval of 45 days, with the results from the first round made available to all the participants in the second round. The results were expressed in percentages and data was analyzed describing the consensus level reached in each question.

RESULTS

A total of 221 experts were invited to participate in the study and a total 214 (96.8%) completed the two rounds. Moderate (65%-85%) to high consensus (≥ 85%) was reached in 51 questions (79.69%), except in the questions dealing with "prevalence", where no consensus was reached. High and moderate consensus was attained for all the questions in three fields (risk factors and indicators, diagnosis and treatment of peri-implant conditions and deficiencies, and prevention and maintenance).

CONCLUSIONS

The present study has provided relevant and useful information on the predictions in the diagnosis and treatment of peri-implant diseases with a high level of consensus among experts. Nevertheless, there is still a lack of agreement in certain domains.

Acid Dentin Lysate Failed to Modulate Bone Formation in Rat Calvaria Defects

Autogenous tooth roots are increasingly applied as a grafting material in alveolar bone augmentation. Since tooth roots undergo creeping substitution similar to bone grafts, it can be hypothesized that osteoclasts release the growth factors stored in the dentin thereby influencing bone formation. To test this hypothesis, collagen membranes were either soaked in acid dentin lysates (ADL) from extracted porcine teeth or serum-free medium followed by lyophilization. Thereafter, these membranes covered standardized 5-mm-diameter critical-size defects in calvarial bone on rats. After four weeks of healing, micro-computed tomography and histological analyses using undecalcified thin ground sections were performed. Micro-computed tomography of the inner 4.5 mm calvaria defects revealed a median bone defect coverage of 91% (CI: 87-95) in the ADL group and 94% (CI: 65-100) in the control group, without significant differences between the groups (intergroup p > 0.05). Furthermore, bone volume (BV) was similar between ADL group (5.7 mm³, CI: 3.4-7.1) and control group (5.7 mm³, CI: 2.9-9.7). Histomorphometry of the defect area confirmed these findings with bone area values amounting to 2.1 mm² (CI: 1.2-2.6) in the ADL group and 2.0 mm² (CI: 1.1-3.0) in the control group. Together, these data suggest that acid dentin lysate lyophilized onto collagen membranes failed to modulate the robust bone formation when placed onto calvarial defects.