Effect of alveolar ridge preservation interventions following tooth extraction: A systematic review and meta-analysis

Biomaterials and therapeutic strategies designed for tooth extraction socket healing

Tooth extraction is the most commonly performed oral surgical procedure, with a wide range of clinical indications. The oral cavity is a complex microenvironment, influenced by oral movements, salivary flow, and bacterial biofilms. These factors can contribute to delayed socket healing and the onset of post-extraction complications, which can burden patients' esthetic and functional rehabilitation. Achieving effective extraction socket healing requires a multidisciplinary approach. Recent advancements in materials science and bioengineering have paved the way for developing novel strategies. This review outlines the fundamental healing processes and cellular-molecular interactions involved in the healing of extraction sockets. It then delves into the current landscape of biomaterials for socket healing, highlighting emerging strategies and potential targets that could transform the treatment paradigm. Building upon this foundation, this review also presents future directions and identifies challenges associated with the clinical application of biomaterials for extraction socket healing.

Self-assembling peptide nanofibers and nanoceramics in a model of alveolar bone repair: Insights from in vivo experiments and clinical trial

Introduction

Tooth extraction initiates a cascade of homeostatic and structural modifications within the periodontal tissues, culminating in alveolar ridge resorption. To prevent ridge resorption following extraction and facilitate successful placement of an implant-supported prosthesis, alveolar ridge preservation was performed.

Methods

In this study, the biocompatibility of a nanocomposite consisting of self-assembling peptide nanofibers (organic phase) and tri-calcium phosphate-nano hydroxyapatite (mineral phase), was evaluated in rabbits. Subsequently, the nanocomposite was grafted onto a model of alveolar bone repair in patients.

Results

The in vivo findings revealed no significant differences in the irritation ranking score and average thickness of the reaction zone between the nanocomposite and control groups. Furthermore, there were no significant differences in the appearance of necrosis, granulation tissue, fibroplasia, neovascularization, and hemorrhage as well as in the number of neutrophils, mast cells, lymphocytes, macrophages, and giant cells between the two groups. The defect area was completely filled with newly formed bone trabeculae and cavities containing bone marrow, indicating angiogenesis, while remnants of the scaffold were observed in the deeper region of the defects, adjacent to the bone marrow, considered osteoinductive. The clinical trial findings (TRN: IR.IUMS.REC.1401.355) demonstrated robust bone regeneration after 3.5 months of socket preservation, whereas the bone in the control group experienced atrophy. The nanocomposite facilitated soft tissue healing without any signs of infection or other periodontal malfunction.

Conclusion

The application of nanotechnology has enhanced the bio-functionality of alloplastic materials, positioning this nanocomposite a promising alternative to autografts and allografts in alveolar bone repair.

The Effectiveness of Platelet Rich Fibrin in Alveolar Ridge Reconstructive or Guided Bone Regenerative Procedures: A Systematic Review and Meta-Analysis

INTRODUCTION AND OBJECTIVES

Clinical studies have shown favorable outcomes following use of platelet rich fibrin (PRF), either alone or in conjunction with biomaterials for alveolar ridge reconstruction (ARR) or guided bone regeneration (GBR) . While PRF application accelerates wound healing and reduces postoperative discomfort, its effects on the alveolar bone gain, as part of ARR or GBR is less clear. Therefore, this study aims to investigate the clinical effectiveness of PRF when used in ARR or GBR, as well as postoperative discomfort following these procedures.

SOURCES

A systematic search using the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) method was performed to include database searches from MEDLINE (OVID interface, 1946 onwards), EMBASE (OVID interface, 1974 onwards) and Global Health (OVID interface, 1973 onwards).

DATA

Of the 74 studies initially identified, 7 studies were included for the systematic review, including 6 randomized controlled trials (RCTs) and 1 cohort study. The meta-analysis showed that the incorporation of PRF as part of ARR or GBR resulted in an increase in horizontal ridge width, a reduction in the rate of resorption increase, while postoperative discomfort was the same or slightly improved. The risk of bias quality was low for only 1 out of the 6 RCTs and the Newcastle Ottawa scale assessment showed that cohort study was of high quality.

CONCLUSION

PRF application in ARR or GBR is associated with increased horizonal alveolar ridge width and reduce rate of graft resorption. However, the findings related to both outcome measures were based on a limited number of studies.

CLINICAL SIGNIFICANCE

PRF application can be effectively used as part of ARR or GBR to increase the horizontal ridge width and reduce the rate of graft resorption.

Tailoring and characterization of bioactive graft material for alveolar bone preservation and regeneration in fresh extraction sockets of dog model

The objective of this study was to tailor an osteoinductive scaffold for alveolar bone regeneration and around immediately placed implants in extraction sockets of dogs. Tailored amorphous multiporous bioactive glass (TAMP -BG) was prepared and characterized for bioactivity and response of human alveolar bone marrow mesenchymal stem cells (hABMSCs). Extraction sockets of twenty-two male mongrel dogs received TAMP-BG in the right side around implant in the distal socket of the mandibular fourth premolar (P4), while the adjacent empty mesial socket of the same tooth was filled with the same graft. Autologous bone chips were used in the left side. Animals were euthanized at 1, 2, 4, 8 &12 weeks for histological and SEM analyses. SEM/EDX, FTIR and XRD analyses displayed formation of a bioactive hydroxycarbonated apatite layer. TAMP-BG significantly increased proliferation and migration of hABMSCs. Histologically, at the 1st week, advanced bone healing was shown in TAMP-BG group. At four weeks bone density was significantly higher forTAMP-BG (92.71% ± 1.71) versus control (62.92% ± 2.02) (P = 0.0001).At eight weeks, significant increase in width of buccal plate and height of lingual bony plate was observedfor TAMP-BG grafted implant.The socket orifice width significantly decreased for autologous bone from 1 to 12 weeks (P < 0.001), while it significantly increased for TAMP-BG (P = 0.03). We conclude that TAMP-BG can provide a preservative dynamic microenvironment following extraction up to three months which can be attributed to its unique physico-chemical characteristics.

Advancements in Hyaluronic Acid Effect in Alveolar Ridge Preservation: A Narrative Review

Background/Objectives: Tooth extraction induces significant alveolar ridge dimensional changes and soft tissue modifications, often leading to challenges in implant placement or conventional prosthetic rehabilitation. Alveolar Ridge Preservation (ARP) strategies aim to mitigate post-extraction resorption of the alveolar ridge, enhancing both the quality and quantity of bone and soft tissue during healing. Hyaluronic acid (HYA) has emerged as a promising biological agent for ARP due to its osteoinductive, antimicrobial, and anti-inflammatory properties. However, the effects of HYA in ARP remain inconsistently reported. This study aims to assess current clinical and preclinical evidence regarding the biological effects of HYA and its application in ARP. Additionally, it evaluates HYA's impact-alone or in combination with other products-on hard and soft tissue dimensional changes, early wound healing, and implant success rates. Methods: A comprehensive electronic literature search was conducted, and studies meeting the inclusion criteria were critically evaluated. Relevant data were extracted from the final selection of articles. Results: Thirteen publications were evaluated. Some studies reported a significantly improved newly formed bone following ARP with intra-socket HYA application as a single approach (p = 0.004). Combining HYA with a bone graft and a free palatal graft resulted in significantly greater amounts of newly formed and mature bone, reduced clinical bone width changes, lower radiographic crestal bone loss (p < 0.01), and diminished radiological volumetric and linear bone resorption (p = 0.018). Short-term follow-up data indicated improved soft tissue healing associated with HYA-based ARP. While HYA appears to have a protective effect on ridge dimensional changes in ARP, other studies reported no significant differences in radiographic bone dimensional changes or soft tissue improvement. Conclusions: The addition of HYA to bone grafts may enhance some ARP outcomes. However, the variability in outcomes and methodologies across the evaluated studies precludes drawing definitive clinical conclusions. Further robust research is needed to clarify HYA's role in ARP. With respect to clinical significance enhancing the understanding of ARP management strategies and their effects on post-extraction sockets empowers clinicians to make more informed decisions. The knowledge of HYA effects facilitates the selection of personalized ARP approaches tailored to optimize outcomes for subsequent interventions.

Histological and histomorphometric evaluation of natural bovine bone substitute with hyaluronate in socket preservation-a report of three cases

Tooth extraction is physiologically followed by resorption of alveolar bone. Surgical method which aims to minimise this reduction in alveolar bone with a goal to provide enough bone volume for dental implant insertion is called socket preservation. The purpose of this article was to asses clinical, histomorphometric and histological results of socket preservation conducted with natural bovine bone substitute with hyaluronate. Three patients with one or more hopeless teeth in posterior region planned for extraction and implant placement were included in these case reports. After atraumatic extractions, empty sockets were filled with the bovine xenograft with hyaluronate, and then covered with collagen sponge. After 4-7.5 months the samples for biopsy were taken and then implants were inserted. The augmented sites healed uneventfully and without any complications. The histological specimens demonstrated new bone formation and osteoclastic activity around the biomaterial, as well as blood vessels in soft tissue. Histomorphometrically, formation of new bone averaged 24.8% ± 4.7% (mean ± standard deviation) in bone biopsies taken from the center of the augmented site, while the residual biomaterial averaged 52.7% ± 4.9% and the soft tissue averaged 22.6% ± 4%. In conclusion, the natural bovine bone substitute with hyaluronate demonstrated excellent osteoconductive potential for bone regeneration.

Novel early vertical ridge augmentation technique

Background/purpose

Multiple augmentation protocols are documented in the literature to rebuild the deficient alveolar ridge after tooth extraction; however, achieving adequate vertical augmentation remains the most challenging goal. This study demonstrated a novel surgical technique of early vertical ridge augmentation for post-dental extraction. This technique offers several biological and technical advantages regarding the timing of the procedure and its relative simplicity compared to other complex techniques.

Materials and methods

This retrospective study consisted of 50 extraction sites from 44 participants who had received early vertical ridge augmentation (VRA) procedures (6-16 weeks post-extraction in either the maxilla or the mandible). The procedures were carried out using titanium tenting screws, freeze-dried bone allografts (FDBA), and xenografts (bovine). Pre- and post-operative cone-beam computed tomography (CBCT) images were taken for all participants 6-9 months after the augmentation surgery to measure the vertical bone gained.

Results

A total of 44 patients were treated with early VRA 6-16 weeks post-dental extraction. The total mean vertical bone gain measured after 6-9 months of augmentation for all cases was 4.64 ± 1.76 mm with no complications encountered. About 80 % of augmented sites met or exceeded the expected vertical bone gain (EVBG). Delaying vertical ridge augmentation until after eight weeks post-extraction, particularly beyond twelve weeks, results in higher rates of EVBG and more consistent average bone gain.

Conclusion

This study indicates that VRA can be achieved predictably by utilizing the early VRA technique, which is relatively straightforward and is associated with a minimal complication.

Feasibility of Immediate, Early and Delayed Implant Placement for Single Tooth Replacement in the Premaxilla: A Retrospective Cone-Beam Computed Tomography Study of 100 Cases

AIM

To assess the feasibility of immediate (IIP), early (EIP) and delayed implant placement (DIP) for single tooth replacement in the premaxilla on the basis of the complete indication area of each approach in routine practice.

MATERIALS AND METHODS

Data from 100 patients (59 women, 41 men, all Caucasians) aged between 19 and 81 years old (mean age 51.71) who had been consecutively treated with a single implant in the premaxilla (13-23) in one private periodontal practice were retrospectively collected. Demographic data, diagnostic information and linear measurements were extracted from patient files and CBCTs. The feasibility of IIP, EIP and DIP was assessed for all cases by both authors, based on the following criteria: availability of apical bone, position of the tooth in relation to the morphology of the alveolar process, buccal bone morphology and presence of midfacial recession. The reasons for not being able to perform an approach, and the viable alternatives for each approach were secondary outcomes. DIP was considered to have been preceded by alveolar ridge preservation (ARP).

RESULTS

Ninety-two patients could be treated by means of IIP, EIP or DIP. In eight patients none of these approaches were possible as they required bone augmentation prior to implant placement. Fifty-two patients (95% CI: 42%-62%) could by treated with IIP, 58 (95% CI: 48%-67%) with EIP and 88 (95% CI: 80%-93%) with DIP. The feasibility proportions of IIP and EIP were significantly lower than the one of DIP (p < 0.001). All patients who could be treated with IIP could also be treated with EIP or DIP. Lack of apical bone for implant anchorage was the main reason for not being able to perform IIP and EIP. Complete loss of the buccal bone wall and the need for bone augmentation prior to implant placement were the reasons for not being able to perform DIP.

CONCLUSION

From the results of this retrospective CBCT analysis, DIP is nearly always possible in contrast to IIP and EIP. Therefore, and since it is much easier than IIP and EIP, inexperienced clinicians should mainly focus on ARP and DIP in clinical practice deferring IIP and EIP until more surgical skills have been acquired.

Pre-extraction alveolar buccal bone overbuilding: a preclinical investigation

BACKGROUND

The pre-extraction overbuilding procedure was designed aiming to mitigate buccal bone resorption following tooth extraction. The objective of this study was to compare the efficacy of pre-extraction and juxta-extraction buccal overbuilding treatments in preserving buccal bone volume following tooth extraction.

MATERIAL AND METHODS

At the test sites (pre-extraction sites), an alveolar crest overbuilding was performed on the buccal aspect of the distal root of the fourth premolar using a xenograft covered with a collagen membrane. No treatment was applied at the control sites. After 3 months, the distal roots of both fourth premolars were extracted and the alveoli were filled with a collagenated xenograft. An overbuilt procedure was performed also at the control sites (juxta-extraction sites). After 3 months, biopsies were collected.

RESULTS

Considering the initial height difference between the lingual and buccal bone plates at the time of extraction, histological evaluation revealed that the resorption of the buccal bone relative to the lingual bone wall was 3.2 mm at the pre-extraction sites and 3.3 mm at the juxta-extraction sites. New bone originated from the residual pre-existing bone crest in an attempt to restore the original dimension.

CONCLUSION

The buccal overbuilding procedures performed three months before tooth extraction did not contribute to preserve the buccal bone crest, despite necessitating an additional surgical procedure. Evidence of ongoing bone regeneration was observed within the augmented space maintained by the biomaterial, suggesting that a prolonged healing period, potentially exceeding six months as indicated by this study, might be required to achieve optimal outcomes.

Analysis of trends in the context of implant therapy in a university surgical specialty clinic: a 20-year retrospective study

OBJECTIVES

To analyze the trends in the context of implant therapy in a 3-year patient population and compare it with data obtained over the last 20 years.

MATERIALS AND METHODS

All adult subjects who received treatment in the context of implant therapy between 2020 and 2022 were included in this retrospective study. Data regarding patient demographics, indications and location of implant therapy, implant characteristics, surgical techniques, complications, and early implant failures were recorded and compared to data obtained in the years 2002-2004, 2008-2010, and 2014-2016.

RESULTS

Between 2020 and 2022, n = 1555 implants were placed in n = 1021 patients. The mean age at implant placement was 59.9 + 15.1 years, demonstrating an increase over time in the age group 61-80 years of 23.1% and > 80 years of 3.2% (p < 0.0001). Single tooth gaps (48.9%) remained the main indication. The use of narrow diameters ≤ 3.5 mm increased (9.4% vs. 26.6%, p < 0.0001), while implant lengths > 10 mm decreased (45.7% vs. 23.5%, p < 0.0001). A reduction in more invasive techniques and an increase in computer-assisted implant surgeries (CAIS) of 19.5% was found.

CONCLUSIONS

The mean age of patients receiving dental implant therapy, with the use of narrow-diameter and shorter implants has progressively increased in the last 20 years. The observed trends suggest a transition from conventional to CAIS, accompanied by the introduction of minimally invasive surgical techniques.

CLINICAL RELEVANCE

The adoption of narrower and shorter implants, along with minimally invasive techniques and CAIS, enables clinicians to tailor treatment plans that accommodate the unique needs of aging patients and optimize clinical outcomes.

The Value of a Tooth for Alveolar Ridge Management; Strategies to Manage Ankylosed Maxillary Anterior Teeth in Young Patients

OBJECTIVE

In the young and growing patient, tooth ankylosis impedes alveolar growth and presents a serious dilemma regarding the best treatment approach. Two common treatment approaches, extraction of the ankylosed tooth or a "wait and see" will result in a compromised alveolar ridge that can affect future prosthetic rehabilitation. The purpose of this article is to discuss five treatment strategies that can be utilized in the management of tooth ankylosis in the growing patient: (1) extraction, (2) decoronation or root submergence, (3) socket shield (partial extraction), (4) segmental osteotomy and (5) replacement with tooth autotransplantation.

OVERVIEW

It is important to understand the biologic sequelae of ankylosis and the value of the tooth for alveolar ridge management. Strategies will be discussed with an emphasis on alveolar ridge management using a natural tooth and root. With an interdisciplinary team, treatment options can then be developed, to achieve more favorable long-term outcomes.

CONCLUSIONS

An understanding of each of these procedures and the proper time for implementation will help the clinician achieve the most optimal long-term outcomes for these growing patients.

CLINICAL SIGNIFICANCE

There are several treatment options for traumatized ankylosed incisors in growing patients. This article will describe the details of these treatment strategies, emphasize the value of the tooth for ridge management and present guidelines about selecting the most optimal strategy based on age, rate of growth, condition of the traumatized tooth, and the definitive prosthetic plan.

NLRP3 deficiency improves bone healing of tooth extraction sockets through SMAD2/3-RUNX2-mediated osteoblast differentiation

Impaired bone healing following tooth extraction poses a significant challenge for implantation. As a crucial component of the natural immune system, the NLRP3 inflammasome is one of the most extensively studied pattern-recognition receptors, and is involved in multiple diseases. Yet, the role of NLRP3 in bone healing remains to be clarified. Here, to investigate the effect of NLRP3 on bone healing, we established a maxillary first molar extraction model in wild-type and NLRP3KO mice using minimally invasive techniques. We observed that NLRP3 was activated during the bone repair phase, and its depletion enhanced socket bone formation and osteoblast differentiation. Moreover, NLRP3 inflammasome activation was found to inhibit osteogenic differentiation in alveolar bone-derived mesenchymal stem cells (aBMSCs), an effect mitigated by NLRP3 deficiency. Mechanistically, we established that the SMAD2/3-RUNX2 signaling pathway is a downstream target of NLRP3 inflammasome activation, and SMAD2/3 knockdown partially reversed the significant decrease in expression of RUNX2, OSX, and ALP induced by NLRP3. Thus, our findings demonstrate that NLRP3 negatively modulates alveolar socket bone healing and contributes to the understanding of the NLRP3-induced signaling pathways involved in osteogenesis regulation.

Efficacy of reactive soft tissue for alveolar ridge preservation: a prospective cohort study

OBJECTIVES

This study aimed to investigate the effect of alveolar ridge preservation (ARP) sealing using reactive soft tissue (RST) or collagen sponge (CS), in combination with deproteinized bovine bone mineral (DBBM), for teeth with bone deficiency.

MATERIALS AND METHODS

In this study, 44 patients were recruited. During ARP therapy, RST or CS was applied for socket sealing. Horizontal and vertical bone dimensions were assessed before extraction (T0) and 6 months after ARP (T2). Modified Masse healing index (HI) was recorded to evaluate the soft tissue healing at 14 days after ARP (T1) and T2. Keratinized mucosa width (KMW) was measured at T0 and T2. Biopsies were collected during implant placement for histological analysis.

RESULTS

This study was finished by 40 patients. Horizontal ridge gains at 1, 3, and 5 mm below the crest were comparable in RST (4.37/5.57/4.16 mm) and CS (3.57/4.66/2.97 mm) groups. Similar vertical bone gains at both buccal and lingual sides were observed in RST and CS groups. Notably, the sockets in the RST group exhibited a significantly better early healing score (6) at T1 relative to the CS group (7) (p = 0.003). There was no significant difference in KMW changes as well as new bone proportion between the groups.

CONCLUSIONS

RST and CS, when combined with DBBM, both effectively reduced ridge resorption in sockets with bone deficiency. RST demonstrated a more favorable effect on the early healing of sockets.

CLINICAL RELEVANCE

RST is a promising socket sealing material in ARP, which reduces bone resorption, and promotes soft tissue healing.

TRIAL REGISTRATION

Clinical trial registration Number: ChiCTR2200061459.

A multi-centre randomized controlled trial on alveolar ridge preservation with immediate or delayed implant placement: Need for soft-tissue augmentation

AIM

To assess the impact of the timing of implant placement following alveolar ridge preservation (ARP) on the need for soft-tissue augmentation (STA) and to identify the risk factors for horizontal and vertical soft-tissue loss.

MATERIALS AND METHODS

Patients with a single failing tooth in the anterior maxilla (15-25) were treated at six centres. Following tooth extraction, they were randomly allocated to the test group (immediate implant placement, IIP) or control group (delayed implant placement, DIP). ARP was performed in both groups and implants were immediately restored with an implant-supported provisional crown. Six months after tooth extraction and ARP, a panel of five blinded clinicians assessed the need for STA on the basis of anonymized clinical pictures and a digital surface model. Lack of buccal soft-tissue convexity and/or mid-facial recession qualified for STA. Pre-operative and 6-month digital surface models were superimposed to assess horizontal and vertical soft-tissue changes.

RESULTS

Thirty patients were included per group (test: 20 females, 10 males, mean age 53.1; control: 15 females, 15 males, mean age 59.8). The panel deemed STA as necessary in 24.1% and 35.7% of the cases following IIP and DIP, respectively. The difference was not statistically significant (odds ratio [OR] = 1.77; 95% confidence interval [CI] [0.54-5.84]; p = .343). Loss of buccal soft-tissue profile was higher following DIP (estimated mean ratio = 1.66; 95% CI [1.10-2.52]; p = .018), as was mid-facial recession (mean difference [MD] = 0.47 mm; 95% CI [0.12-0.83]; p = .011). Besides DIP, regression analysis identified soft-tissue thickness (-0.57; 95% CI [-1.14 to -0.01]; p = .045) and buccal bone dehiscence (0.17; 95% CI [0.01-0.34]; p = .045) as additional risk factors for mid-facial recession. Surgeons found IIP significantly more difficult than DIP (visual analogue scale MD = -34.57; 95% CI [-48.79 to -20.36]; p < .001).

CONCLUSIONS

This multi-centre randomized controlled trial failed to demonstrate a significant difference in the need for STA between IIP and DIP when judged by a panel of blinded clinicians. Based on objective soft-tissue changes, patients with thin buccal soft tissues, with a buccal bone dehiscence and treated with a delayed approach appeared particularly prone to soft-tissue loss.

Ultrasound-based jawbone surface quality evaluation after alveolar ridge preservation

BACKGROUND

Bone readiness for implant placement is typically evaluated by bone quality/density on 2-dimensional radiographs and cone beam computed tomography at an arbitrary time between 3 and 6 months after tooth extraction and alveolar ridge preservation (ARP). The aim of this study is to investigate if high-frequency ultrasound (US) can classify bone readiness in humans, using micro-CT as a reference standard to obtain bone mineral density (BMD) and bone volume fraction (BVTV) of healed sockets receiving ARP in humans.

METHODS

A total of 27 bone cores were harvested during the implant surgery from 24 patients who received prior extraction with ARP. US images were taken immediately before the implant surgery at a site co-registered with the tissue biopsy collection location, made possible with a specially designed guide, and then classified into 3 tiers using B-mode image criteria (1) favorable, (2) questionable, and (3) unfavorable. Bone mineral density (hydroxyapatite) and BVTV were obtained from micro-CT as the gold standard.

RESULTS

Hydroxyapatite and BVTV were evaluated within the projected US slice plane and thresholded to favorable (>2200 mg/cm3; >0.45 mm3/mm3), questionable (1500-2200 mg/cm3; 0.4-0.45 mm3/mm3), and unfavorable (<1500 mg/cm3; <0.4 mm3/mm3). The present US B-mode classification inversely scales with BMD. Regression analysis showed a significant relation between US classification and BMD as well as BVTV. T-test analysis demonstrated a significant correlation between US reader scores and the gold standard. When comparing Tier 1 with the combination of Tier 2 and 3, US achieved a significant group differentiation relative to mean BMD (p = 0.004, true positive 66.7%, false positive 0%, true negative 100%, false negative 33.3%, specificity 100%, sensitivity 66.7%, receiver operating characteristics area under the curve 0.86). Similar results were found between US-derived tiers and BVTV.

CONCLUSION

Preliminary data suggest US could classify jawbone surface quality that correlates with BMD/BVTV and serve as the basis for future development of US-based socket healing evaluation after ARP.

Alveolar ridge preservation in posterior maxillary teeth for reduction in the potential need for sinus floor elevation procedures: A pilot study

OBJECTIVES

To investigate the effects of alveolar ridge preservation (ARP) on ridge height, sinus pneumatization and the potential need for lateral sinus augmentation following extraction in the posterior maxilla.

MATERIALS AND METHODS

This randomized controlled pilot study included 28 patients requiring extraction in the posterior maxilla with bone height between 6 and 8 mm. The sites were randomly allocated to either unassisted socket healing (Control), ARP with deproteinized bovine bone mineral (DBBM) (Test 1), or collagen-stabilized DBBM (Test 2) groups. Pre- and post-operative CTs at 4 months were taken to determine changes in ridge heights, sinus volume, and the need for sinus floor elevation (SFE) procedures for cases where the residual mid-ridge height was < 5 mm. Site-level analyses for changes in vertical ridge dimensions and sinus volume pre- and post-extraction/ARP were conducted using paired t-tests. Differences in mean changes in vertical ridge dimensions and sinus volume between the groups were determined using one-way ANOVA.

RESULTS

Significantly greater mean mid-ridge height reduction occurred in the control group (-2.7 ± 0.9 mm) compared to Test 1 (0.9 ± 3.7 mm) and Test 2 (1.0 ± 2.8 mm) groups (p < .05). No significant changes in mean mid-ridge height were found in either test groups. Volumetric analysis showed a significantly greater increase in sinus volume in the control group (0.7 ± 0.7 cm3) compared to Test 1 (n = 3, -0.7 ± 0.8 cm3) group (p = .03). 89% of patients in the control group would require lateral window SFE  compared to Test 1 (42.8%) and Test 2 (40%) groups.

CONCLUSION

ARP was effective in attenuating height changes in the middle of the ridge and may reduce sinus pneumatization following extraction in the posterior maxilla. This could potentially decrease the need for more invasive sinus augmentation procedures.

Does alveolar ridge preservation reduce the need for sinus floor elevation: A comparative study to spontaneous healing

INTRODUCTION

In cases of atrophy in the maxillary posterior region, characterized by reduced vertical bone volume, implant placement becomes challenging. Augmentation procedures like sinus lifts are often needed to address insufficient bone volume. This study aims to explore if alveolar ridge preservation, using a bovine bone substitute and a porcine collagen membrane, significantly decreases the need for sinus lifts compared to natural wound healing after tooth extraction.

MATERIALS AND METHODS

In this comparative clinical study, 40 patients requiring a total of 53 extractions were assigned to one of the following groups: a test group with bovine bone substitute material (Straumann® XenoFlex) and a porcine collagen membrane (Jason® membrane), or a control group with spontaneous socket healing. After 6 months, digital volume tomography was performed for implant planning.

RESULTS

For seven patients from the control group (n = 22 extracted sites) sinus lift augmentations were performed while only four sinus lift procedures were performed in the test group (n = 31 extracted sites), indicating a higher need for sinus augmentation procedures in the control group, however not statistically different on a p value of 0.05 (p = 0.168). In the control group, the mean value of the radiographically measured bone height (mesial and distal) was 11.13 ± 2.12 mm preoperatively before tooth extraction, while it was 11.3 ± 2.17 mm postoperatively after implant placement. In contrast, the mean value in the test group was 11.78 ± 3.09 mm preoperatively and 11.92 ± 2.79 mm postoperatively. Statistical analysis revealed no significant difference between the two groups (odds ratio 0.32; 95% CI: 0.08, 1.26; p = 0.951). The implant survival rate in the control group was 100%, compared to 96.77% in the test group.

CONCLUSION

Within the limits of this study, the use of bovine bone substitute and a porcine resorbable membrane after tooth extraction in the posterior maxilla seems to reduce the need for sinus augmentation in comparison to spontaneous healing although the difference was not statistically significant. Additionally, the Alveolar Ridge Preservation in the test group made external sinus floor elevation unnecessary compared to the control group. The change in radiographically measured bone height pre- and postoperatively showed no significant difference between the two groups.

Magnesium Membrane Shield Technique for Alveolar Ridge Preservation: Step-by-Step Representative Case Report of Buccal Bone Wall Dehiscence with Clinical and Histological Evaluations

BACKGROUND/OBJECTIVES

Despite the increased use of new resorbable magnesium membranes, there are no reported cases or studies on the use of resorbable magnesium membranes in combination with bone grafts for alveolar ridge preservation (ARP) in cases with severe buccal bone wall dehiscence. This case report aimed to evaluate the effectiveness of the magnesium membrane shield technique in conjunction with bone grafting for ARP, assessing both clinical outcomes and histological bone regeneration.

METHODS

A 44-year-old female patient presented with a vertical fracture on tooth 24 (FDI Notation System) accompanied with complete destruction of the buccal bone wall. The treatment plan included tooth extraction, ARP using a combination of anorganic bovine bone and autologous bone grafting, and the application of a magnesium membrane as a shield to the pre-existing buccal wall. Six months post-procedure, a bone biopsy was taken from the implant site using a trephine bur.

RESULTS

Clinical and radiological evaluations six months after the procedure demonstrated sufficient bone volume for implant placement. Additionally, in the next three months, soft tissue conditioning with a provisional crown resulted in an aesthetically and functionally satisfactory outcome. Histological analysis of the bone biopsy revealed well-formed new bone in direct contact with residual biomaterial, with no signs of inflammation. Osteocytes were clearly visible within the newly formed bone matrix, indicating successful bone maturation. Active osteoblasts were observed along the bone-biomaterial interface, suggesting ongoing bone remodeling and integration. Additionally, histomorphometric evaluation revealed 47% newly formed bone, 32% soft tissue, and 19% residual biomaterial.

CONCLUSIONS

This case demonstrates the potential of the magnesium shield technique as an ARP technique in cases with severe buccal wall dehiscence. The technique yielded satisfactory clinical outcomes and promoted successful bone regeneration, as confirmed by histological analysis.

Effect of Local Zoledronic Acid Application in Alveolar Bone Healing: An Experimental Study

BACKGROUND

This experimental study aimed to assess the three-dimensional and histological changes of the alveolar socket with local application of ZA.

METHODS

Nine male New Zealand white rabbits were randomly allocated into 4-, 8-, and 12-week groups after the extraction of 4 incisor teeth. The upper and lower right sockets were filled with ZA + collagen sponge (ZA-CS group), while the left sockets were filled with collagen sponge alone (CS group) postoperatively. At 4, 8, and 12 weeks (T1, T2, and T3) after the extraction, radiographic and histomorphometric evaluations were conducted for both groups.

RESULTS

The increase in alveolar bone density of the ZA-CS group at T2 and T3 was significantly higher than the CS group (P＜0.01). Three-dimensional evaluations demonstrated no statistically significant differences in ridge height and width between the 2 groups at T2 and T3. On histological evaluation, the ZA-CS group included significantly fewer TRAP-positive cells than the CS group at T1 (P＜0.05). In ALP staining, all cases in both groups were classified as positive at each time point. Masson trichrome staining showed significantly higher mean red collagen volume fraction in the ZA-CS group (76.09%, 79.64%) than in the CS group (66.17%, 69.22%) at T2 and T3, respectively (P＜0.05 and ＜0.01).

CONCLUSIONS

Although local ZA application with collagen sponge did not reduce alveolar ridge contraction, it improved the bone density and maturity of newly formed bone after tooth extraction.

Ridge preservation using octacalcium phosphate collagen to induce new bone containing a vascular network of mainly Type H vessels

Many studies have shown that it is important to use bone grafts that are easy to mold, bioabsorbable, and stable over time. We focused on Type H blood vessels, which were discovered by Kusumbe et al. in 2014 to be responsible for the interaction between angiogenesis and osteogenesis. The aim of this study was to assess the effect of octacalcium phosphate collagen (OCP/Col), on the healing processes of the extraction socket and the alveolar bone surrounding the extraction socket. Ridge preservation of rat lower first molars was conducted using OCP/Col, and a series of experiments involving micro-CT scanning, observations of new bone, bone morphometry measurements, histological and immunohistochemical analyses, and second harmonic generation imaging were conducted to analyze bone mass, bone quality, angiogenesis, and mechanical properties. The results demonstrate that the calcification level was not very high when using OCP/Col for RP. Moreover, the newly formed bone is rich in vascular components and collagen fibers that are essential for bone tissue remodeling. These characteristics of OCP/Col in RP could contribute significantly to the construction of a rich vascular network around dental implants immediately after implant placement and the subsequent acquisition of osseointegration and reconstruction of the surrounding tissue.

Does defect configuration affect the outcomes of alveolar ridge preservation? An experimental in vivo study

PURPOSE

The purpose of this study was to compare the bone healing potential of 1-, 2-, and 3-wall defects following alveolar ridge preservation (ARP) treatment, as well as to evaluate the efficacy of ARP as a treatment option for destructive sites.

METHODS

Three groups, characterized by 1-, 2-, and 3-wall defects, were randomly assigned to the maxillary second, third, and fourth premolars in each of 8 beagle dogs. Each defect was created at either the mesial or distal root site of the tooth, which was hemi-sectioned and extracted. The contralateral root was preserved to superimpose with the experimental site for histomorphometric analysis. For each site, either spontaneous healing (SH; control) or ARP (test intervention) was randomly applied. Each group was divided in half and underwent a healing period of either 4 or 12 weeks. The Mann-Whitney U test and Kruskal-Wallis test were used for histomorphometric analyses. Statistical significance was set at P<0.05.

RESULTS

Qualitative analysis revealed a higher percentage of new bone in the apical area compared to the coronal area, regardless of defect type and healing period. In quantitative analysis, the 3-wall defect exhibited a significantly higher percentage of mineralization in the ARP group after 12 weeks of healing (ARP: 61.73%±7.52%; SH: 48.84%±3.06%; P=0.029). An increased percentage of mineralization was observed with a greater number of remaining bony walls, although this finding did not reach statistical significance.

CONCLUSIONS

Within the limitations of this study, ARP treatment for compromised sockets appears to yield a higher percentage of mineralization compared to SH. Although the effectiveness of the remaining bony walls was limited, their presence appeared to improve the percentage of mineralization in ARP treatment.

Assessment of soft and hard tissue changes following micro crestal flap-Alveolar ridge preservation and augmentation at molar extraction sites in patients with stage III/IV periodontitis: A randomized controlled trial

AIM

This study aimed to assess hard and soft tissue contour changes following micro crestal flap-alveolar ridge preservation (MCF-ARP) and natural healing (NH) in periodontally compromised molar extraction sites and to analyse the feasibility and need for bone augmentation during implant therapy.

MATERIALS AND METHODS

Fifty-six patients with 70 sites were randomized into two groups at the site level (35 sites from 31 patients in the test group and 35 sites from 29 patients in the control group). Among whom, four patients contributed one tooth to the control group and one tooth to the test group. Hard tissue indicators were measured using cone beam computed tomography performed before tooth extraction and 6 months after surgery. Soft tissue contour changes were assessed using intraoral scanning performed before and immediately after surgery and also 2 weeks and 1, 3 and 6 months after surgery.

RESULTS

Six months after surgery, the MCF-ARP group showed less resorption in buccal bone height (p = .032) and greater augmentation in central bone height (p = .001) and ridge width (p = .009). The mean, vertical and horizontal collapse of buccal soft tissue contour in the MCF-ARP group were 0.95 mm (p = .010), 0.61 mm (p = .019) and 0.56 mm (p = .013) less than that in the NH group, respectively. There were significantly (p = .007) fewer sites in the MCF-ARP group than in the NH group (0% vs. 26.7%) for staged bone augmentation and more sites that could be treated with simple implant procedure in the MCF-ARP group than in the NH group (71.9% vs. 56.6%).

CONCLUSIONS

Compared with NH, MCF-ARP reduced bone resorption in periodontally compromised molar extraction sites and maintained the buccal soft tissue contour. MCF-ARP reduces the need for complex bone augmentation procedures in implant therapy.

TRIAL REGISTRATION

Chinese Clinical Trial Register (ChiCTR) ChiCTR2200056335. Registered on 4 February 2022, Version 1.0.

Effect of radiation cross-linked collagen scaffold in alveolar ridge preservation of extraction socket

This study aimed to evaluate the properties of radiation cross-linked collagen scaffold (RCS) and its efficacy for alveolar ridge preservation (ARP). RCS was prepared from collagen dispersion by electron beam irradiation and freeze-drying. The microstructure, swelling ratio, area alteration and mechanical properties of RCS were characterized. Fifty-four New Zealand rabbits performing incisor extraction on maxilla and mandible were randomly assigned into positive, sham operation or treatment groups. Micro-computed tomography (micro-CT) scans, performed after 1, 4, and 12 weeks of surgery, were to assess changes in ridge height at buccal and palatal side, in ridge width and in micromorphological parameters. Histological analysis accessed socket microarchitecture. The results showed that RCS had stable mechanical properties and morphologic features that provided a reliable physical support for ARP. Dimensional changes in treatment group revealed significantly greater vertical height at buccal (5.32 [3.37, 7.26] mm, p < .0001) and palatal (4.37 [2.66, 6.09] mm, p < .0001) side, and horizontal width at the maxilla (0.16 [0.04, 0.28] mm, p < .01) and mandible (0.33 [0.11, 0.54] mm, p < .01) than those in sham operation group after 12 weeks. The treatment group had advantage than positive group in vertical height preservation, quantitatively. The order and density of bone trabeculae were improved in treatment group. These findings indicated that RCS had the potential to serve as an effective scaffold for ARP.

Autologous platelet concentrates in alveolar ridge preservation: A systematic review with meta-analyses

In order to evaluate the therapeutic advantages of various autologous platelet concentrates (APC) as a single biomaterial during alveolar ridge preservation (ARP), a systematic review with meta-analyses was conducted. PubMed, EMBASE, Web of Science, and Scopus were screened for randomized controlled trials (RCTs) that were released prior to 2024. The selected papers compared an APC with either unassisted healing (blood clot) or another biomaterial during ARP (third molars were not included). The outcome parameters included alveolar bone dimension alterations, soft tissue healing, and post-op pain intensity. The search yielded 35 papers (33 studies), one applying platelet-rich plasma (PRP), six using plasma rich in growth factors (PRGF), and 28 using leukocyte- and platelet-rich fibrin (L-PRF). These studies showed a large heterogeneity (e.g., outcome parameters, timing, surgical approach, and inclusion criteria), which hindered drawing strong conclusions. In most studies, however, ARP with PRP, PRGF, and L-PRF alone produced faster soft tissue healing, less post-extraction pain, less alveolar ridge resorption, more socket bone fill, and a higher bone density when compared to unassisted (spontaneous) healing. The ultimate benefit appears to be significantly influenced by the surgical approach. Limited literature exists comparing APC with other biomaterials for ARP, resulting in inconclusive data. APC application for ARP is a promising strategy to improve soft and hard tissue healing and reduce post-extraction pain.

Cyanoacrylate versus Collagen Membrane as a Sealing for Alveolar Ridge Preservation: A Randomized Clinical Trial

This study involved a randomized clinical trial that included 140 patients. Alveolar ridge preservation was performed with xenografts. Sealing in the control group consisted of a collagen membrane versus cyanoacrylate in the test group. The dental implants were placed immediately after extraction. The variables were evaluated at 3, 12, and 18 months of follow-up. Pearson's chi-squared test was used for qualitative variables and the Student t-test for related samples was used for quantitative variables. The change in buccolingual alveolar bone width was significantly greater in the CMX group than in the CX group after three months (p < 0.005). However, significance was not reached at the other follow-up timepoints (p > 0.005). CAL showed significantly greater values in the CMX group than in the CX group (p < 0.005), and MBL proved greater in the CMX group than in the CX group, with p < 0.001. Five membrane exposures were recorded in the CMX group. Cyanoacrylate as a sealing method for alveolar ridge preservation seems to afford better clinical and radiological results than collagen membrane.

Alveolar ridge preservation versus early implant placement in single non-molar sites: A systematic review and meta-analysis

OBJECTIVES

The aim of this systematic review and meta-analyses was to evaluate the outcomes of alveolar ridge preservation (ARP) following extraction of non-molar teeth in comparison to early implant placement (EIP) in terms of clinical and radiographic changes, need for additional augmentation at the time of implant placement, patient-reported outcomes, and implant failure rate.

METHODS

Electronic databases were searched to identify randomized and non-randomized studies that compared ARP to EIP. The risk of bias was assessed using the Cochrane Collaboration's Risk of Bias tool. Data were analyzed using a statistical software program.

RESULTS

A total of 106 studies were identified, of which five studies with 198 non-molar extraction sockets in 198 participants were included. Overall meta-analysis showed significant differences in changes in midfacial mucosal margin (mean difference (MD) -0.09; 95% confidence interval (CI) -0.17 to -0.01; p = .03) and ridge width (MD -1.70; 95% CI -3.19 to -0.20; p = .03) in favor of ARP. The use of ARP was also associated with less need for additional augmentation at implant placement, but the difference was not statistically significant.

CONCLUSIONS

Within the limitation of this review, ARP following extraction of non-molar teeth has short-term positive effects on soft tissue contour, mucosal margin and thickness, and alveolar ridge width and height. It can also simplify future implant treatment by minimizing the need for additional augmentation.

Intraoral ultrasonography image registration for evaluation of partial edentulous ridge: A methodology and validation study

OBJECTIVES

Ultrasound (US) reveals details for diagnosing soft- and hard-tissue dimensions around teeth, implants, and the edentulous ridge, not seen in 2D radiographs. Co-registering free-hand US scans with other 3D modalities presents reliability challenges. This study first aims to develop and validate a registration method to longitudinally reproduce US images of the jawbone on a simulator. In addition, it also evaluates the degree of the anatomical match in humans between US images acquired by the proposed registration method and the commonly used freehand acquisitions in comparison to cone beam computed tomography (CBCT) and intra-oral optical scan (IOS), used as references.

METHODS

A previously introduced ultrasound phantom was employed as a CBCT-US hybrid, suitable for training and technique development of US guides in edentulous ridges. After establishing feasibility in the phantom, the methodology was validated in a cohort of 24 human subjects (26 cases). Soft tissues were delineated on US and IOS, and hard tissues on US and CBCT. US accuracy and repeatability from both guided and freehand scans (non-guided) was assessed as the average distance between US and the references.

RESULTS

Guided US images resembled the references more closely than freehand (non-guided) scans. Notably, delineation of soft and hard tissues was significantly more accurate when employing guides. In the phantom, guided scans exhibited an absolute mean deviation of 81.8 µm for gingiva and 90.4 µm for bone, whereas non-guided scans showed deviations of 150.4 µm and 177.2 µm, respectively. Similarly, in vivo, guided US outperformed non-guided US, with gingiva deviations of 125 µm and 196 µm, and bone deviations of 354 µm and 554 µm, respectively.

CONCLUSIONS

By using a registration method, guided US scans improved repeatability and accuracy of mapping hard and soft tissue of the edentulous ridge when compared to non-guided scans.

CLINICAL RELEVANCE

This guided US imaging method could lay the foundation for longitudinal evaluation of tissue behavior and dimensional changes with improved accuracy.

Local delivery of pamidronate with collagen matrix mitigates buccal bone resorption following immediate implant placement - An experimental in vivo study

AIMS

The aim of this experimental in vivo pilot study was to evaluate the effect of the local delivery of pamidronate within a collagen membrane on the changes in the buccal soft and hard tissue dimensions at the time of immediate implant placement and whether this effect was influenced by the placement of bone substitutes.

METHODS

In six beagle dogs, the distal roots of the third and fourth premolars were extracted, and immediate implants were placed. Treatment groups were randomly allocated to each socket: (i) covering the buccal bone with pamidronate-soaked collagen membrane (BP group), (ii) filling the gap defect with synthetic bone substitute (BS group), (iii) filling the gap defect with synthetic bone substitute and covering the buccal bone with pamidronate soaked collagen membrane (BP/BS group), (iv) no treatment (control group). Intraoral scanning was performed immediately after the surgery and at 20 weeks. Histomorphometric and micro-computed tomography (CT) outcomes were evaluated at 20 weeks.

RESULTS

The micro CT analysis demonstrated that the BP group showed no apparent difference in vertical bone level with residual mesial root area, while control group showed significant buccal bone resorption at the implant site. The histomorphometric analysis demonstrated that the vertical bone level of buccal plate was significantly differed between the BP and control group (0.34 ± 0.93 and 1.27 ± 0.56 mm, respectively; p = .041). There was no statistically significant difference in the horizontal ridge width (HRW 1, 2, 3) among the groups. Also, the thickness, height and buccal contours of the soft tissue did not reveal significant changes among the groups.

CONCLUSION

The local delivery of pamidronate to the outer surface of the buccal wall at the time of immediate implant placement effectively limits buccal bone resorption. The results from the present investigation should be interpreted with caution, as well as its clinical translatability. Further investigation is needed to understand the pamidronate binding and releasing kinetic, as well as the ideal carrier of this drug for its topical application.

Competence of allogenic demineralized tooth matrix in socket seal surgery for alveolar ridge preservation: a randomized control clinical trial

OBJECTIVES

To assess and compare the clinical, radiological, and histological outcomes of socket seal surgery between two protocols: deproteinized demineralized tooth matrix (dpDTM) and freeze-dried bone allograft (FDBA) each covered with a free gingival graft.

MATERIALS AND METHODS

Twenty extraction sockets in the anterior or premolar region were randomly allocated to either the dpDTM or FDBA protocol (n = 10 per group). Measurements of the alveolar ridge changes were obtained using an intraoral scanner and cone-beam computed tomography at 3 months post-operation. Three-month post surgery, the dental implant was installed (n = 5 per group), bone biopsies were obtained for histomorphometrical and micro-computed tomography analyses. Implant stability quotients (ISQs) were determined and compared at 3 months post-implant.

RESULTS

Lower significant reductions in buccal alveolar ridge height and hard tissue volume were observed in dpDTM group compared to FDBA group at 3 months (0.25 ± 0.35 mm vs. 1.60 ± 0.66 mm [p = .000] and 9.64 ± 15.39% mm3 vs. 31.45 ± 18.11% mm3 [p = .010], respectively). At the same time, lower soft tissue volume reduction was detected in the dpDTM group compared to FDBA group (4.21 ± 5.25% mm3 vs. 5.25 ± 5.79% mm3). No statistically significant difference in the percentage of mineralized tissue formation was found between dpDTM group (53.39 ± 11.16%) and FDBA group (49.90 ± 3.27%). Even though the ISQ in the dpDTM group showed a higher value than the FDBA group at 3 months post-implant, the results were without statistical significance.

CONCLUSIONS

Alveolar ridge preservation using dpDTM is an efficacious procedure for providing the conditions for the development of functional and esthetic implants.

Comparative Effectiveness of an Autologous Dentin Matrix for Alveolar Ridge Preservation

An urgent issue is the preservation or reconstruction of the volume of bone tissue in planning and surgical treatment in the fields of medicine, such as traumatology, orthopedics, maxillofacial surgery and dentistry. After tooth extraction, resorption of the bone tissue of the alveolar crest of the jaws occurs, which must either be further eliminated by performing additional operations or using osteoplastic material for socket preservation at the extraction stage. Background and Objectives: The aim of the study was a comparative analysis of various osteoplastic materials used to preserve the volume of bone tissue in the preimplantation period. Materials and Methods: As part of the study, 80 patients were treated, who underwent socket preservation using xenografts, plasma enriched with growth factors, an autologous dentin matrix (ADM) and hydroxyapatite. Results: The results of the treatment 16 weeks after removal were comprehensively analyzed using a morphometric analysis of the bone's volume, cone beam tomography and morphological examination of burr biopsy specimens, as well as by determining the stability of the installed implant at different stages of treatment. Conclusions: The lowest level of bone tissue resorption according to the CBCT data was noted in the ADM and xenograft groups. It should be noted that the use of osteoplastic material in jaw surgery when reconstructing alveolar defects is an essential procedure for preventing the atrophy of bone tissue.

Alveolar Ridge Preservation Using a Collagenated Xenograft: A Randomized Clinical Trial

OBJECTIVES

This study sought to evaluate the efficacy of cancellous bovine bone mineral granules and 10% porcine collagen (deproteinized bovine bone mineral with collagen [DBBM-C]; (OCS-B Collagen® [Straumann XenoFlex], NIBEC, Korea) in a mouldable block form, with or without socket seal, using autogenous free gingival graft (FGG).

METHODS

Fifty-four patients were included and randomly assigned to one of three groups: (1) spontaneous healing (control group), (2) alveolar ridge preservation (ARP) using DBBM-C (DBBM-C group), and (3) ARP employing DBBM-C sealed with FGG (DBBM-C/FGG group). Bone biopsy and implant fixture placement were performed 180 days after ARP. Cone-beam computed tomography, histological analysis, implant stability, and three-dimensional volumetric analysis were conducted.

RESULTS

Of the 54 patients, 4 dropped out owing to loss of follow-up and osseointegration failure. The changes in alveolar bone during follow-up were not significantly different. Between 84- and 180-day postextraction, the volume of the DBBM-C and DBBM-C/FGG groups was maintained at 3 mm below the alveolar ridge crest (0.72 ± 0.80 mm, 6.05 ± 6.69%), whereas the volume in the control group decreased (-0.37 ± 1.31 mm, -2.10% ± 8.37%) (P = .026). The DBBM-C/FGG group exhibited less horizontal ridge resorption at 1 mm below the alveolar crest (-9.19 ± 5.09 mm, -73.67% ± 32.53%) between preextraction and 84 days postextraction (P = .049). In all groups, the implant stability quotient remained above 70.

CONCLUSIONS

Within the limitations of this study, both ARP using DBBM-C with and without socket sealing effectively preserved the width dimension of the alveolar ridge, with no significant difference in alveolar bone resorption. However, socket sealing appeared to enhance the stability of the bone graft and bone quality.

CLINICAL RELEVANCE

The use of DBBM-C for ARP seems to aid in volume maintenance as compared with spontaneous healing. Gingival sealing with an FGG can help maintain the width of the alveolar ridge. This clinical trial was not registered prior to participant recruitment and randomization. This study was registered at WHO ICTRP (https://trialsearch.who.int/Trial2.aspx?TrialID=KCT0008266).

The adjunctive effect of polydeoxyribonucleotide on bone formation in alveolar ridge preservation: A pre-clinical in vivo study

AIM

This study investigated the adjunctive effect of polydeoxyribonucleotide (PDRN) on bone formation in alveolar ridge preservation (ARP) sockets.

MATERIALS AND METHODS

Both mandibular second, third and fourth premolars of eight beagle dogs were randomly divided into ARP and ARP/PDRN groups. Following tooth extraction, ARP procedures were conducted using collagenized alloplastic graft material and bilayer collagen membrane soaked with normal saline (ARP group) or PDRN (ARP/PDRN group) for 10 min before application. Both groups were also randomly allocated to 2-, 4- or 12-week healing subgroups. The primary endpoint of this study was to compare histomorphometric differences between ARP and ARP/PDRN. The secondary endpoints of this study were to compare micro-CT analysis and three-dimensional volumetric measurement between the two groups.

RESULTS

In the histomorphometric analysis, the ARP/PDRN group exhibited greater new bone formation at coronal, middle and total position compared with the ARP group at 2-week healing. The number of newly formed blood vessels was higher in the ARP/PDRN group than in the ARP group at 2- and 4-week healing. In micro-CT analysis, the mean new bone volume/total bone volume between ARP and ARP/PDRN was statistically significant at 2-week healing. Ridge volume alterations were significantly decreased in the ARP/PDRN group during entire healing time compared with the ARP group, especially on the buccal side.

CONCLUSIONS

The application of PDRN in ARP might provide additional benefits for early bone regeneration and maintenance of buccal ridge volume.

Efficacy and safety of a new heterologous fibrin biopolymer on socket bone healing after tooth extraction: An experimental pre-clinical study

AIM

To assess the efficacy of heterologous fibrin biopolymer (HFB) in promoting alveolar bone healing after tooth extraction in rats.

MATERIALS AND METHODS

The upper right incisors of 48 Wistar rats were extracted. Toothless sockets were filled with HFB (HFBG, n = 24) or blood clot (BCG, n = 24). The tooth extraction sites were subjected to micro-computed tomography (micro-CT), histological, histomorphometric and immunohistochemical (for Runt-related transcription factor 2/Runx2 and tartrate-resistant acid phosphatase/TRAP) analyses on days 0, 7, 14 and 42 after extraction.

RESULTS

Socket volume remained similar between days 0 and 14 (69 ± 5.4 mm3), except in the BCG on day 14, when it was 10% lower (p = .043). Although the number of Runx2+ osteoblasts was high and similar in both groups (34 × 102 cells/mm2), the HFBG showed lower inflammatory process and osteoclast activity than BCG at 7 days. On day 14, the number of Runx2+ osteoblasts remained high and similar to the previous period in both groups. However, osteoclast activity increased. This increase was 55% lower in the HFBG than BCG. In the BCG, the presence of an inflammatory process and larger and numerous osteoclasts on day 14 led to resorption of the alveolar bone ridge and newly formed bone. On day 42, numbers of Runx2+ osteoblast and TRAP+ osteoclasts decreased dramatically in both groups. Although the BCG exhibited a more mature cortical bone formation, it exhibited a higher socket reduction (28.3 ± 6.67%) and smaller bone volume (37 ± 5.8 mm3) compared with HFBG (socket reduction of 14.8 ± 7.14% and total bone volume of 46 ± 5.4 mm3).

CONCLUSIONS

HFB effectively suppresses osteoclast activity and reduces alveolar bone resorption compared with blood clot, thus preventing three-dimensional bone loss, particularly during the early healing period. HFB emerges as a promising biopharmaceutical material for enhancing healing processes after tooth extraction.

Long-term complications and management of dental trauma in the adult patient - Part 2: discoloured, displaced and missing teeth

The second paper in this two-part review series aims to outline the long-term complications of dental trauma in the adult patient in relation to discoloured, displaced or missing teeth. A brief overview of the cause of discolouration is outlined, followed by assessment and management options. These can include bleaching, veneers, or crown restorations to mask the discolouration. Displacement of teeth from the socket can occur due to luxation injuries. Management can include simple digital manipulation, surgical repositioning, or orthodontic extrusion based on the severity of extrusion and the time from injury. Teeth can be lost early or in the long-term following dental trauma and associated hard and soft tissues deficiencies may also ensue. Replacement options can include a removable partial prosthesis, resin-retained bridge or dental implants. Often, hard and soft tissue augmentation procedures may be required to address any defects and rebuild lost anatomical contours. A thorough assessment followed by the development of a sound management plan which takes patients' general and local factors into account can ensure a predictable and successful treatment outcome. This would end in an aesthetically pleasing and a functionally stable result for the patient.

How effective is dentin autograft for socket preservation and implant site preparation: A systematic review protocol

Background

Socket preservation is a surgical procedure aimed at preserving the dimensions of the alveolar bone following tooth extraction. It is performed by filling the extraction socket with bone graft material with or without a barrier membrane. Recently, dentine obtained from extracted teeth has been tried as an autograft for socket preservation. Studies have compared the use of dentin to other bone grafts, however, systematic reviews evaluating the efficacy of dentin for socket preservation are limited. Hence, this systematic review protocol is proposed to generate evidence on the efficacy of dentin as a viable alternative to other bone graft materials for socket preservation.

Methods

This systematic review protocol was prepared according to the Methodological Expectations of the Cochrane Intervention Reviews (MECIR) guidelines. It will be conducted using the Cochrane Handbook for Systematic Review of Interventions. PubMed, Scopus, Web of Science, EMBASE, Epistemonikos, Cochrane Central, and EBSCO databases and clinical trial registries, will be searched for all randomized controlled trials (RCTs) and non-randomized studies that have used autologous dentin graft (either in particulate/putty, or/matrix form) for socket preservation. The radiographic and clinical assessment of bone and soft tissue healing of the preserved sockets along with patient-related outcomes following surgery will be assessed. The risk of bias assessment of the RCTs and Non-RCTs will be assessed using the 'Cochrane Risk of Bias assessment tool (ROB II) and ROBINS-I respectively. The certainty of evidence will be assessed by the GRADE approach.

Discussion

This evidence is important for dental clinicians and the public to make an informed decision when choosing graft material for socket preservation. The extracted teeth are considered biological waste; however, this evidence provides scope for using a less invasive autograft for bone regenerative procedures.

Systematic review registration

PROSPERO: CRD42021201958 (Registered on 15/02/2021).

Alveolar Ridge Preservation With Fibro-Gide or Connective Tissue Graft: A Randomized Controlled Trial of Soft and Hard Tissue Changes

OBJECTIVE

The aim of this study was to evaluate the effectiveness of a novel biomaterial (FG) for alveolar ridge preservation compared to CTG in terms of soft tissue thickness and bone dimensional changes.

MATERIALS AND METHODS

A randomized clinical trial was conducted on 30 patients who required extraction of 30 hopeless mandibular posterior teeth. All patients went through atraumatic tooth extraction, and then, they were randomly allocated to either a CTG, an FG, or a spontaneous healing (SH) group (1:1:1). All patients received a dental implant placed 6 months postoperatively. The soft tissue thickness and bone dimensional changes were measured before and 6 months after the procedure.

RESULTS

The study's analysis revealed statistically significant differences in buccal gingival thickness and dimensional bone changes across the three examined groups after 6 months (p < 0.05). The SH group had lower gingival thickness (1.31 ± 0.65 mm) and higher vertical resorption (-1.46 ± 1.67 mm at the buccal aspect) compared with the CTG and FG groups. The CTG and FG groups had similar gingival thickness (2.42 ± 0.70 and 3.00 ± 0.71 mm, respectively) and bone width reduction (+0.86 ± 2.31 and +0.93 ± 2.38 mm, respectively), whereas the CTG group had lower vertical bone loss (-0.30 ± 1.09 mm at the buccal aspect) than the FG group (-0.47 ± 2.30 mm at the buccal aspect).

CONCLUSION

FG and CTG demonstrate equivalent soft tissue thickness and comparable horizontal bone dimension outcomes in ARP.

Use of autologous tooth-derived material as a graft in the post-extraction socket. Split-mouth study with radiological and histological analysis

BACKGROUND

The healing process after tooth removal involves bone remodelling which implies some loss of alveolar bone volume. Among materials proposed for minimising this remodelling and preserving the bone, autologous dental tissue is a promising option, but more data are needed. In this context, we evaluated size and density changes using cone beam computed tomography in autologous dental material (ADM)-preserved sockets compared to controls, and assessed biological responses by histological analysis.

METHODS

A split-mouth study was conducted including 22 patients, who underwent removal of ≥ 2 single-rooted teeth with intact sockets, assigning one socket to the experimental group which received ADM for alveolar preservation and another to the control group, which only underwent blood clot stabilisation. Cone beam computed tomography was performed postoperatively (week 0) and at weeks 8 and 16 to assess socket size and bone density. Histological analysis was carried out on trephine biopsies taken (Ø4 × 4.5 mm) from the experimental group.

RESULTS

Less horizontal shrinkage was observed in the ADM group, especially at week 16 considering the group-by-time interaction for the following variables: difference in height between the lingual and buccal alveolar crests (-1.00; p < .01; 95% CI: -0.28 - -1.73), and half-widths, measured as the distance from the long axis of the missing tooth to the buccal alveolar crest at 1 mm (-0.61; p < .01; 95% CI: -0.18 - -1.04) and at 3 mm (-0.56; p < .01; 95% CI: -0.15 - -0.97) below the crest, with mean decreases of 1.07 and 2.14 mm in height difference, 0.66 and 1.32 mm in half-width at 1 mm and 0.43 and 1.02 mm in half-width at 3 mm in ADM and control groups respectively. Densitometry analysis showed higher bone densities in Hounsfield units in the ADM group considering all factors analysed regardless of time point and socket third (coronal, middle, or apical). Histologically, there were no signs of inflammation or foreign body reaction, and dentin particles were surrounded by and in close contact with bone tissue.

CONCLUSION

These results add to the evidence that dentin can be used successfully as a material for alveolar socket preservation, given its desirable mechanical and biological properties, and warrant larger studies.

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.

Comparative Analysis of Two Different Techniques for Ridge Preservation Following Tooth Extraction: A Clinical and Radiographic Study

Background

Ridge preservation following tooth extraction is essential for maintaining the alveolar bone structure and facilitating successful dental implant placement. Various techniques have been proposed for this purpose, but there remains a need for comparative analysis to determine their efficacy.

Materials and Methods

This clinical and radiographic study compared two different techniques for ridge preservation: Technique A and Technique B. Fifty patients requiring tooth extraction were randomly assigned to either Technique A or Technique B group. Clinical parameters including pain, swelling, and soft tissue healing were evaluated postoperatively. Radiographic assessments were conducted to measure the dimensional changes in the alveolar ridge at baseline and after 3 months using cone-beam computed tomography (CBCT).

Results

In the Technique A group, postoperative pain scores averaged 2.3 (±0.5) on a visual analog scale (VAS), while in the Technique B group, the average pain score was 2.5 (±0.6). The swelling was minimal in both groups with no significant difference. Soft tissue healing was satisfactory in both groups. Radiographically, the mean vertical bone loss was 1.2 mm (±0.3) in the Technique A group and 0.9 mm (±0.4) in the Technique B group, with a statistically significant difference (P < 0.05).

Conclusion

Both Technique A and Technique B demonstrated favorable outcomes in terms of postoperative discomfort and soft tissue healing. However, Technique B showed superior preservation of vertical ridge dimensions compared to Technique A. Therefore, Technique B may be considered more effective for ridge preservation following tooth extraction.

Alveolar Ridge Preservation Using a Novel Species-Specific Collagen-Enriched Deproteinized Bovine Bone Mineral: Histological Evaluation of a Prospective Case Series

In recent years, the significance of maintaining the alveolar ridge following tooth extractions has markedly increased. Alveolar ridge preservation (ARP) is a commonly utilized technique and a variety of bone substitute materials and biologics are applied in different combinations. For this purpose, a histological evaluation and the clinical necessity of subsequent guided bone regeneration (GBR) in delayed implantations were investigated in a prospective case series after ARP with a novel deproteinized bovine bone material (95%) in combination with a species-specific collagen (5%) (C-DBBM). Notably, block-form bone substitutes without porcine collagen are limited, and moreover, the availability of histological data on this material remains limited. Ten patients, each scheduled for tooth extraction and desiring future implantation, were included in this study. Following tooth extraction, ARP was performed using a block form of C-DBBM in conjunction with a double-folded bovine cross-linked collagen membrane (xCM). This membrane was openly exposed to the oral cavity and secured using a crisscross suture. After a healing period ranging from 130 to 319 days, guided trephine drilling was performed for implant insertion utilizing static computer-aided implant surgery (s-CAIS). Cores harvested from the area previously treated with ARP were histologically processed and examined. Guided bone regeneration (GBR) was not necessary for any of the implantations. Histological examination revealed the development of a lattice of cancellous bone trabeculae through appositional membranous osteogenesis at various stages surrounding C-DBBM granules as well as larger spongy or compact ossicles with minimal remnants. The clinical follow-up period ranged from 2.5 to 4.5 years, during which no biological or technical complications occurred. Within the limitations of this prospective case series, it can be concluded that ARP using this novel C-DBBM in combination with a bovine xCM could be a treatment option to avoid the need for subsequent GBR in delayed implantations with the opportunity of a bovine species-specific biomaterial chain.

Microbial colonization in the partially exposed nonabsorbable membrane during alveolar ridge preservation

AIM

This study evaluated the impact of the partial exposition of the nonabsorbable membrane (dPTFE) on microbial colonization during bone healing.

MATERIALS AND METHODS

Patients indicated for tooth extraction were randomized to dPTFE group (n = 22) - tooth extraction and alveolar ridge preservation (ARP) using an intentionally exposed dPTFE membrane and USH group (n = 22) - tooth extraction and unassisted socket healing. Biofilm samples were collected at the barrier in the dPTFE and on the natural healing site in the USH after 3 and 28 days. Samples from the inner surface of the dPTFE barrier were also collected (n = 13). The microbiome was evaluated using the Illumina MiSeq system.

RESULTS

Beta diversity was different from 3 to 28 days in both groups, and at 28 days, different microbial communities were identified between therapies. The dPTFE was characterized by a higher prevalence and abundance of gram-negative and anaerobic species than USH. Furthermore, the inner surface of the dPTFE membrane was colonized by a different community than the one observed on the outer surface.

CONCLUSION

Intentionally exposed dPTFE membrane modulates microbial colonization in the ARP site, creating a more homogeneous and anaerobic community on the inner and outer surfaces of the membrane.

CLINICAL RELEVANCE

DPTFE promoted faster biofilm colonization and enrichment of gram-negative and anaerobes close to the regenerated site in the membrane's inner and outer surfaces. dPTFE membrane can be used exposed to the oral site, but approaches for biofilm control should still be considered. The study was retrospectively registered at Clinicaltrials.gov (NCT04329351).

The distally anchored connective tissue graft platform for papilla enhancement: A case report

BACKGROUND

As the need for using dental implants to replace single missing teeth grows, so does the demand for greater esthetic results. However, achieving complete interproximal papillae fill in single-tooth implant restorations remains a challenge. The distally anchored connective tissue platform is a novel soft tissue augmentation technique that consists of harvesting an autogenous connective tissue graft from the palate, folding it, and positioning it at the level of the distal occlusal and buccal surfaces with the help of a distal sling suture to the adjacent distal tooth.

METHODS

This case report describes how a maxillary central incisor with compromised hard and soft tissues were replaced using a comprehensive treatment plan.

RESULTS

The clinical outcomes showed stable mucosal margin levels and complete papillae fill. The patient expressed satisfaction with the achieved results.

CONCLUSIONS

The distally anchored connective tissue graft platform performed at the time of implant placement emerges as a viable and effective soft tissue augmentation technique that yields highly esthetic results.

KEY POINTS

Why is this case new information? To the best of our knowledge, this is the first case report in the literature using the distally anchored connective tissue platform. What are the keys to successful management of this case? Adequate diagnosis and decision-making, resulting in a treatment plan focused on reconstructing both soft and hard tissues in a single-tooth implant within the esthetic area, yield favorable clinical, radiological, and patient-reported outcomes. What are the primary limitations to success in this case? The primary limitation of this study is its reliance on a single case report.

Changes of the Alveolar Bone Ridge Using Bone Mineral Grafts and Collagen Membranes after Tooth Extraction: A Systematic Review and Meta-Analysis

BACKGROUND

Alveolar preservation techniques for esthetic or functional purposes, or both, are a frequently used alternative for the treatment of post-extraction sockets, the aim of which is the regeneration of the lesion and the preservation of the alveolar bone crest.

METHODS

Studies published in PubMed (Medline), Web of Science, Embase, and Cochrane Library databases up to January 2024 were consulted. Inclusion criteria were established as intervention studies, according to the PICOs strategy: adult subjects undergoing dental extractions (participants), with alveoli treated with bone mineral grafts and collagen membranes (intervention), compared to spontaneous healing (comparison), and observing the response to treatment in clinical and radiological measures of the alveolar bone crest (outcomes).

RESULTS

We obtained 561 results and selected 12 studies. Risk of bias was assessed using the Cochrane Risk of Bias Tool, and methodological quality was assessed using the Joanna Briggs Institute. Due to the high heterogeneity of the studies (I2 > 75%), a random-effects meta-analysis was used. Despite the trend, no statistical significance (p > 0.05) was found in the experimental groups.

CONCLUSIONS

The use of bone mineral grafts in combination with resorbable collagen barriers provides greater preservation of the alveolar ridge, although more clinical studies are needed.

Endodontic and restorative management of an adult with avulsion of multiple teeth: A case report with 5 years and 9 months of follow-up

Simultaneous avulsion of four or more teeth is a rare event. This case report examines the dental care given to an adult who, during a bicycle accident, experienced the avulsion of a mandibular incisor as well as all of his maxillary incisors. In the immediate aftermath of the accident, four out of the five incisors were located, promptly collected, and stored in a tooth rescue box, all within a 20-min window. Replantation and splinting were performed on the day of the accident. Endodontic treatment involved sequential intracanal dressing with an antibiotic-corticosteroid paste followed by calcium hydroxide prior to root canal obturation. 3 months post-accident, signs of external replacement resorption (ERR) began to appear in all the replanted teeth. The gap created by the missing maxillary central incisor was managed with a three-unit fixed dental prosthesis, despite the onset of ERR in the incisors used as abutment teeth. Regular follow-ups showed a relatively slow ERR progression rate over a span of nearly 6 years. The patient expressed satisfaction with both the esthetic and functional outcomes. This case, marked by multiple avulsions, underscores the importance of immediate and appropriate intervention alongside the imperative for carefully considered long-term management strategies. Given the decelerated bone remodeling rate in adults, ERR generally progresses at a slower pace than in children. Accordingly, this case demonstrates the viability of retaining replanted teeth over the long term, even when these teeth have been subjected to nonphysiological storage for extended durations, a factor known to impede periodontal healing.

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.

Comparison of histologic and radiographic changes of sockets grafted with LPRF and sockets without intervention after tooth extraction

OBJECTIVES

After tooth extraction, marked resorption occurs in extraction socket walls, leading to functional and esthetic problems in that area. One of the methods introduced to reduce this resorption is the use of platelet derivatives. This study aimed to evaluate the effects of leukocyte and platelet-rich fibrin (L-PRF) on the changes following tooth extraction.

MATERIALS AND METHODS

The participants were 24 patients who needed to replace at least one single-rooted tooth with an implant. They were randomly divided into test and control groups. After the tooth extraction, the sockets in the test group received LPRF clots, while in the control group, the sockets were left free of any interventions. CBCT scans were obtained from the extraction site both immediately after the tooth extraction and 8 weeks later. The histologic biopsy was also obtained while the implant site was being prepared 8 weeks after the extraction.

RESULTS

The average vertical bone loss in the buccal crest was not significantly different between the two groups (1.67 ± 1.67 in the test group and 2.3 ± 1.36 in the control group; mean difference =  - 0.36, 95% CI: - 1.65-0.93, p-value = 0.57). Nor was the difference in resorption of the palatal wall (mean difference =  - 0.19, 95% CI: - 1.51.12, p-value = 0.76). The mean ridge width resorption in 25% of the coronal aspect of sockets was also measured in the test (1.30 ± 0.66) and control group (0.58 ± 0.95) (mean difference = 0.73, 95% CI: 0.03-1.42, p-value = 0.04). The new bone formation in histologic view was not statistically different between groups (p-value = 0.15).

CONCLUSION

The LPRF neither reduces the rate of ridge resorption in vertical or horizontal dimensions of extraction sockets nor induces more new bone formation.

CLINICAL RELEVANCE

This study helps dentists choose the appropriate material for ridge preservation.

Learn, unlearn, and relearn post-extraction alveolar socket healing: Evolving knowledge and practices

OBJECTIVE

This review was to offer a comprehensive analysis of currently available evidence on post-extraction alveolar socket healing, including i) the histological and molecular events during alveolar socket healing, ii) the dimensional ridge alterations after socket healing and controversies relating to sinus pneumatisation, iii) the patient-specific factors, procedural elements, and site-related variables influencing socket healing, iv) techniques and effectiveness of alveolar ridge preservation (ARP) procedure, and v) the philosophies and cost-effectiveness of ARP in clinical practice.

SOURCES AND STUDY SELECTION

To investigate the dimensional profiles of the alveolar ridge following unassisted healing, an overview of systematic reviews was conducted in February 2024 by two independent reviewers. Four electronic databases were searched in Pubmed, Embase, Web of science and Cochrane Library between 2004 and 2024 to identify all relevant systematic reviews on post-extraction healing. A further manual search of reviews was also conducted. The articles were further reviewed in full text for relevance. The AMSTAR-2 appraisal tool was adopted to assess methodological quality. Current research pertaining to other listed objectives was objectively analysed in narration.

DATA

11 out of 459 retrieved studies were selected and ultimately covered in this review on the dimensional changes of alveolar ridge following natural healing: Seven systematic reviews and four systematic reviews with meta-analyses. The methodological quality of all included reviews was critically low.

CONCLUSION

This review thoroughly examines the healing profiles of post-extraction alveolar sockets and highlights the dynamic process with overlapping phases and the inter-individual variability in outcomes. ARP procedure is a potential strategy for facilitating prosthetic site development, while the current evidence is limited. Herein, an individualised and prosthetically driven approach is crucial. Further well sized and designed trials with novel biomaterials need to be undertaken, and the role of artificial intelligence in predicting healing and assisting clinical decision-making could be explored.

CLINICAL SIGNIFICANCE

By advancing our understanding of alveolar socket healing and its management strategies, clinicians can make more informed decisions regarding patient and site level assessment and selection, surgical techniques, and biomaterial choices, ultimately contributing to the enhanced healing process with reduced complications and improved quality of life for patients undergoing tooth extraction and dental implant treatments.

Half- and full-grafting alveolar ridge preservation with different sealing materials: A three-arm randomized clinical trial

OBJECTIVE

The objective of this study is to investigate the effect of different alveolar ridge preservation (ARP) approaches on bone resorption and their potential for facilitating implant placement.

MATERIALS AND METHODS

Patients who underwent one or two tooth extractions with a desire for restoration were included in the study. The participants were randomly assigned to one of three groups for ARP. The groups were as follows: (1) Half grafting of bovine bone mineral (DBBM-C) covered with non-resorbable dense polytetrafluoroethylene (dPTFE) membrane (Test 1 group); (2) Half grafting of bovine bone mineral (DBBM-C) covered with collagen membrane (Test 2 group); and (3) Full grafting with collagen membrane (DBBM-C + Collagen membrane) as the Control group. After 6-month healing period, the evaluation encompassed clinical, radiographic, implant-related outcomes, and the factors contributing to hard and soft tissue alterations.

RESULTS

Enrollment in this study comprised 56 patients. At the 6-month follow-up, radiographic analysis in computed beam computed tomography images was conducted for 18, 19, and 19 patients with 18, 20, and 20 tooth sites in Test 1, Test 2, and Control groups, respectively. Additionally, a total of 15, 17, and 17 patients with 15, 18, and 17 implants were evaluated. Based on radiographic analysis, all groups showed limited ridge resorption at 1 mm from crest horizontally (Test 1: 1.29 ± 1.37; Test 2: 1.07 ± 1.07; Control: 1.54 ± 1.33 mm, p = 0.328), while the Control group showed greater radiographic bone height gain in mid-crestal part vertically (Test 1: 0.11 ± 1.02; Test 2: 0.29 ± 0.83; Control: -0.46 ± 0.95 mm, p = 0.032). There were no significant intergroup differences in terms of keratinized mucosal width, bone density, insertion torque, and the need of additional bone graft. However, the use of a dPTFE membrane resulted in a significantly higher vertical mucosal thickness (Test 1: 2.67 ± 0.90; Test 2: 3.89 ± 1.08; Control: 2.41 ± 0.51 mm, p < 0.001).

CONCLUSIONS

The study showed comparable dimensional preservation with limited vertical shrinkage, while thin buccal bone plate, non-molar sites, and large discrepancy between buccal and palatal/lingual height may contribute to greater shrinkage. Thicker mucosa with dPTFE membrane required further investigation for interpretation.

CLINICAL TRIAL REGISTRATION NUMBER

NCT06049823. This clinical trial was not registered prior to participant recruitment and randomization.

A comparative analysis of particulate bovine bone substitutes for oral regeneration: a narrative review

PURPOSE

Particulate bovine bone substitutes (BS) are commonly used in oral regeneration. However, more literature is needed focusing on comparative analyses among various particulate bovine BS. This study evaluates pre-clinical and clinical data of different particulate bovine BS in oral regeneration.

METHODS

A narrative review was conducted by screening the PubMed database Included in the review were pre-clinical and clinical studies until 2024 comparing a minimum of two distinct particulate bovine BS. In addition to examining general data concerning manufacturing and treatment processes, biological safety, physical and chemical characteristics, and graft resorption, particular emphasis was placed on assessing pre-clinical and clinical data related to ridge preservation, sinus floor elevation, peri-implant defects, and various forms of alveolar ridge augmentation utilizing particulate bovine BS.

RESULTS

Various treatment temperatures ranging from 300 to 1,250 °C and the employment of chemical cleaning steps were identified for the manufacturing process of particulate bovine BS deemed to possess biosecurity. A notable heterogeneity was observed in the physical and chemical characteristics of particulate bovine BS, with minimal or negligible graft resorption. Variations were evident in particle and pore sizes and the porosity of particulate bovine BS. Pre-clinical assessments noted a marginal inclination towards favorable outcomes for particulate bovine BS subjected to higher treatment temperatures. However, clinical data are insufficient. No distinctions were observed regarding ridge preservation, while slight advantages were noted for high-temperature treated particulate bovine BS in sinus floor elevation.

CONCLUSIONS

Subtle variances in both pre-clinical and clinical outcomes were observed in across various particulate bovine BS. Due to inadequate data, numerous considerations related to diverse particulate bovine BS, including peri-implant defects, must be more conclusive. Additional clinical studies are imperative to address these knowledge gaps effectively.

Evaluation of Alveolar Ridge Dimensions by Socket Preservation Therapy Using a Bone Graft and Platelet-Rich Fibrin: A Randomized Controlled Trial

BACKGROUND

Following the loss of a tooth, the new edentulous area of the ridge will undergo several adaptive modifications due to changes in function within and surrounding the socket. This bone resorption explains the need for socket preservation techniques in areas of esthetic concerns and functional demands. Demineralized freeze-dried bone allograft (DFDBA) possesses greater osteoinductive potential due to the exposure of bone morphogenetic protein (BMP-3​​​​​​)​and collagen fibrils and can be used efficiently in socket preservation techniques. DFDBA yields better results when combined with an autologous platelet concentrate, such as platelet-rich fibrin. Therefore, we formulated this randomized controlled clinical trial to assess the clinical and radiovisiographical outcomes of platelet-rich fibrin (PRF) and DFDBAs for extraction socket preservation in humans at different time intervals.

MATERIALS AND METHODS

This was a randomized controlled trial with 100 people as study subjects, and they were randomly divided into two groups: the test group (DFDBA and PRF placed in the extraction socket) and the control group (natural healing of the extraction socket). Clinical and radiographic evaluation using radiovisiography (RVG) was done at baseline, three-month, and six-month intervals. Cone-beam computed tomography (CBCT) was used at six months to determine the bone density in the test and control groups.

RESULTS

When compared from baseline to six months, the percentage change in clinical and RVG measurements for the test group was 15.96% (11.9064 mm) and 16.77% (12.1840 mm), respectively, whereas for the control group, it was 46.09% (14.0396 mm) and 47.61% (14.5716 mm), thus indicating lesser bone resorption in the test group as opposed to the control group. CBCT values also showed greater bone density for the test group (682.3120 HU) than the control group (503.8336 HU).

CONCLUSION

This study demonstrates the advantages of DFDBA bone graft with PRF compared to natural healing in achieving socket preservation by maintaining the marginal and buccolingual bone levels.