Early implant placement versus ridge preservation and delayed implant placement: Analysis of profilometric, clinician- and patient-reported outcomes from a two-centre RCT

OBJECTIVES

To compare early implant placement (EP) to alveolar ridge preservation and delayed implant placement (ARP/DP) in terms of contour changes, along with clinician- and patient-reported outcome measures (PROMs) until the delivery of the implant-supported restoration.

MATERIALS AND METHODS

Patients with a failing single tooth in the maxilla or mandible were recruited in two centres. After tooth extraction, patients were randomly assigned (1:1) to either EP or ARP/DP. At abutment connection and crown delivery, the buccal contour changes at 3 mm below the mucosal margin (primary outcome) along with clinician- (ease of treatment) and patient-reported outcomes were assessed using numeric rating scales and OHIP-14.

RESULTS

A total of 46 patients were analysed. The mean buccal contour at abutment connection decreased by -1.2 ± 0.6 mm in group EP and -1.6 ± 0.8 mm in group ARP/DP (estimated mean difference; 0.45 [95%CI, -0.02; 0.94]; p = .061) with no significant differences between the groups. ARP/DP was consistently easier than EP across all stages of the surgery (estimated mean difference; 2.0 [95%CI, 1.3; 2.7] p < .001): during flap elevation (EP: 4.8 vs. ARP/DP: 1.6), implant placement (EP: 5.7 vs. ARP/DP: 2.2) and wound closure (EP: 3.4 vs. ARP/DP: 1.6). Both interventions improved quality of life but patients who underwent ARP/DP were significantly more satisfied at the time of crown delivery (ARP/DP: 9.6 vs. EP: 9.1, p = .02).

CONCLUSIONS

EP and ARP/DP show no significant differences in buccal contour changes, aesthetics and patient-reported outcomes. However, ARP/DP is an easier procedure at all stages of the surgery compared to EP and could therefore be the preferred therapy for less experienced clinicians.

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.

Influence of freeze-dried bone allograft on free gingival graft survival and alveolar ridge maintenance in socket seal procedures: a randomized controlled clinical trial

PURPOSE

This study aimed to investigate the viability of free gingival grafts (FGG) and assess clinical and radiographic changes in the alveolar ridge following socket seal surgery with or without freeze-dried bone allograft (FDBA).

MATERIALS AND METHODS

Twenty-eight anterior and premolar tooth extractions were randomly allocated to 2 groups: socket graft of FDBA sealed with FGG (n = 15) and control with empty sockets sealed solely with FGG (n = 13). Photographs taken at 3, 7, 14, and 30 days post-surgery assessed FGG viability. Alveolar ridge volume was clinically evaluated via intraoral scanners before surgery and at 1 and 3 months post-surgery. CBCT scans taken immediately post-surgery and 3 months later assessed alveolar ridge dimensions.

RESULTS

FGG viability in both groups increased from day 3 and reached the maximum score on day 14. Alveolar ridge volume reduction at 3 months in the FDBA group was comparable to the control group. Buccal alveolar bone height reduction was significantly higher in the FDBA group than the control group, while palatal alveolar bone height was comparable. Alveolar bone width reduction was evident but not statistically significant between the groups. The FDBA group exhibited a significant alteration in bone volume compared to the control group.

CONCLUSION

Viability of FGG was not affected by graft filling materials. Sealing the socket with FGG effectively preserved socket integrity and ridge volume in minor socket defects using either graft filling material or not. This study was registered on 4 January 2021 on Thai Clinical Trials Registry (TCTR20210104001).

Biomechanical Investigation of the Osseointegration of Titanium Implants With Different Surfaces Placed With Allogeneic Bone Transfer

Allogeneic grafts can be preferred to autogenous grafts in plastic and oral-maxillofacial surgery for vertical and horizontal bone deficiencies. Implant surface properties are an important factor in osseointegration. This study aims to evaluate the osseointegration levels of titanium implants with machined, sand-blasted, and acid-etched (SLA) and resorbable blast material (RBM) surfaces placed together with allogeneic bone tissue transplantations obtained from the tibia bone using biomechanical method. Twenty-five female Sprague-Dawley rats were included in the study. The rats were divided into groups in which machined (n=7), SLA (n=7), and RBM (n=7) surface implants were placed with the transplantation of bone taken from the tibia. Four rats (both left and right tibias) were used as donors. Grafts and implants were surgically placed in the corticocancellous part of the metaphyseal area of the tibia bones of rats. At the end of the 4-week experimental setup, all rats were killed, and the implants and surrounding bone tissue were subjected to biomechanical reverse torque analysis (N/cm). Sand-blasted acid-etched surface implants were observed to have higher biomechanical osseointegration levels than RBM and machined surface implants (P<0.05). No statistical difference could be detected between the RBM and machined surface implants (P>0.05). On the basis of the limited results of this study, it can be concluded that the osseointegration levels of SLA surface implants placed with allogeneic bone transplantation may be better than those of machined and RBM surface implants.

Platelet-rich fibrin as an autologous biomaterial for bone regeneration: mechanisms, applications, optimization

Platelet-rich fibrin, a classical autologous-derived bioactive material, consists of a fibrin scaffold and its internal loading of growth factors, platelets, and leukocytes, with the gradual degradation of the fibrin scaffold and the slow release of physiological doses of growth factors. PRF promotes vascular regeneration, promotes the proliferation and migration of osteoblast-related cells such as mesenchymal cells, osteoblasts, and osteoclasts while having certain immunomodulatory and anti-bacterial effects. PRF has excellent osteogenic potential and has been widely used in the field of bone tissue engineering and dentistry. However, there are still some limitations of PRF, and the improvement of its biological properties is one of the most important issues to be solved. Therefore, it is often combined with bone tissue engineering scaffolds to enhance its mechanical properties and delay its degradation. In this paper, we present a systematic review of the development of platelet-rich derivatives, the structure and biological properties of PRF, osteogenic mechanisms, applications, and optimization to broaden their clinical applications and provide guidance for their clinical translation.

Advancements in alveolar bone grafting and ridge preservation: a narrative review on materials, techniques, and clinical outcomes

This narrative review systematically explores the progression of materials and techniques in alveolar ridge preservation (ARP). We commence by delineating the evolution from traditional ARP methods to cutting-edge alternatives, including platelet-rich fibrin, injectable bone repair materials, and hydrogel systems. Critical examination of various studies reveals these innovative approaches not only accelerate bone healing but also significantly improve patient-reported outcomes, such as satisfaction, pain perception, and overall quality of life. Emphasis is placed on the correlation between advanced ARP techniques and enhanced patient comfort and clinical efficacy, underscoring their transformative potential in dental implantology. Highlighting the effectiveness of ARP, the implant survival rate over a span of 5 to 7 years was high, showcasing the reliability and success of these methods. Further, patients expressed high aesthetic satisfaction with the soft tissue outcome, evidenced by an average visual analog scale (VAS) score of 94. This positive aesthetic appraisal is linked to the clinical health of implants, potentially due to the employment of tooth-supported surgical guides. The economic analysis reveals a varied cost range for bone graft substitutes ($46.2 to $140) and socket sealing materials ($12 to $189), with a noteworthy correlation between the investment in barrier membranes and the diminished horizontal and vertical ridge resorption. This suggests that membrane usage significantly contributes to preserving ridge dimensions, offering a cost-effective strategy for enhancing ARP outcomes. In conclusion, this review illuminates the significant advancements in ARP, highlighting the shift towards innovative materials and techniques that not only promise enhanced bone regeneration and reduced healing times but also improve patient satisfaction and aesthetic outcomes. The documented high implant survival rate and the beneficial economic implications of membrane use further validate the effectiveness of contemporary ARP strategies, paving the way for their broader adoption in dental implantology.

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

OBJECTIVES

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

Postextraction ridge preservation by using dense PTFE membranes: A systematic review and meta-analysis

STATEMENT OF PROBLEM

The use of dense polytetrafluoroethylene (dPTFE) membranes in alveolar ridge preservation may help reduce the risk of bacterial contamination and infection, maintaining the soft-tissue anatomy. However, systematic reviews on their efficacy in postextraction sites are lacking.

PURPOSE

The purpose of this systematic review and meta-analysis was to assess the efficacy of alveolar ridge preservation with dPTFE membranes when used alone or in combination with bone grafting materials in postextraction sites.

MATERIAL AND METHODS

An electronic search up to February 2021 was conducted by using PubMed, Embase, and the Cochrane library to detect studies using dPTFE membranes in postextraction sites. An additional manual search was performed in relevant journals. Clinical and radiographic dimensional changes of the alveolar ridge, histomorphometric, microcomputed tomography, implant-related findings, and rate of complications were recorded. One-dimensional meta-analysis was performed to calculate the overall means and 95% confidence intervals (α=.05).

RESULTS

A total of 23 studies, 14 randomized controlled trials, 4 retrospective cohort studies, 3 case series, and 2 prospective nonrandomized clinical trials, met the inclusion criteria. Five studies were included in the quantitative analysis. The meta-analysis revealed that the use of dPTFE membranes resulted in a statistically significant (P=.042) increase in clinical keratinized tissue of 3.49 mm (95% confidence interval [CI]: 0.16, 6.83) when compared with extraction alone. Metaregression showed that the difference of 1.10 mm (95% CI: -0.14, 2.35) in the radiographic horizontal measurements was not significant (P=.082), but the difference of 1.06 mm (95% CI: 0.51, 1.62) in the radiographic vertical dimensional change between dPTFE membranes+allograft and extraction alone was statistically significant (P<.001).

CONCLUSIONS

The use of dPTFE membranes was better than extraction alone in terms of keratinized tissue width and radiographic vertical bone loss.

Risk Factors for Early Implant Failure and Selection of Bone Grafting Materials for Various Bone Augmentation Procedures: A Narrative Review

Implant therapy is now an established treatment with high long-term success and survival rates. However, early implant failure, which occurs within one year of superstructure placement, occurs at a higher rate than late failure, which is represented by peri-implantitis caused by bacterial infection. Furthermore, various risk factors for early failure have been reported, including patient-related factors, such as systemic diseases, smoking, and bone quality and quantity, as well as surgery-related factors, such as surgeons' skill, osteogenesis technique, and selection of graft material, and implant-related factors, such as initial implant fixation and implant length diameter. Due to the wide variety of relevant factors reported, it is difficult to identify the cause of the problem. The purpose of this review is to discuss the risk factors associated with various types of bone augmentation which have a close causal relationship with early implant failure, and to determine the optimal bone grafting material for bone augmentation procedures to avoid early implant failure.

Innovative Alveolar Ridge Preservation Surgical Technique with Immediate Dental Implant Placement: A Retrospective Case Report of 1-Year Follow-Up

Following tooth extraction, the alveolar ridge undergoes morphological and dimensional changes, including a clot formation that is gradually replaced by granulation tissue. Studies indicate that both horizontal and vertical ridge dimensions decrease after extraction; however, these changes can be mitigated through grafting with biomaterials and barrier membranes. Alveolar ridge preservation (ARP) techniques are employed to counteract bone resorption postextraction, encompassing periosteal inhibition and modified periosteal inhibition (MPI) techniques. The Degidi clot chamber technique offers a means to achieve biomaterial-free extraction sockets, promoting healing and osteointegration. This study aims to present the first rehabilitation of a postextraction dental implant in the maxilla using an innovative ARP procedure via a MPI technique. The technique does not involve autologous or heterologous grafting materials; instead, a cortical lamina and a customized screw are used in conjunction with the blood clot. The primary objective is to protect the vestibular cortical bone from preosteoclastic aggression, which can trigger bone resorption. The technique employs a 0.5-mm cortical lamina to mechanically shield the vestibular cortical bone, preventing vestibular cortical bone resorption and increasing its thickness without the need for biomaterial insertion, relying on the blood clot. The effectiveness of the technique was assessed through a 12-month postimplantation cone-beam computed tomography scan, revealing a 0.5-mm increase. Although based on a single case, the 1-year follow-up results are promising, and further studies are warranted to validate the technique's efficacy.

Efficacy of alveolar ridge preservation with xenografts and resorbable socket sealing materials in the esthetic region: A systematic review with meta-analyses

AIM

The present systematic review aimed to identify and summarize the clinical, radiographic, and histological outcomes of alveolar ridge preservation using bone xenografts and absorbable sealing materials compared with spontaneous healing in the esthetic zone.

MATERIALS AND METHODS

Randomized clinical trials (RCTs) fulfilling specific eligibility criteria were included. Two review authors independently searched for eligible studies, extracted data from the published reports and performed the risk of bias assessment (RoB 2 tool). Study results were summarized using random effects meta-analyses.

RESULTS

Thirteen articles concerning 10 RCTs were included, involving a total of 357 participants. Most of studies were considered as "low" risk of bias. Meta-analyses indicated less horizontal (difference in means-MD = 1.88 mm; p < 0.001), vertical mid-buccal (MD = 1.84 mm; p < 0.001) and vertical mid-lingual (MD = 2.27 mm; p < 0.001) bone resorption in alveolar ridge preservation compared to spontaneous healing as assessed clinically. Bone changes assessed radiographically showed consistent results in terms of horizontal (at 1 mm: MD = 1.84 mm, p < 0.001), vertical mid-buccal (MD = 0.95 mm; p < 0.001) and mid-lingual (MD = 0.62 mm; p = 0.05) resorption. Part of the bone resorption in the spontaneous healing group was compensated by soft-tissues, since the observed differences between groups in linear ridge reduction evaluated through cast models superimposition were smaller (MD = 0.52 mm; p < 0.001).

CONCLUSIONS

Alveolar ridge preservation with xenogeneic bone substitutes and non-autogenous resorbable socket sealing materials is efficacious in reducing post-extraction bone and ridge changes in the esthetic region.

In Vitro Handling Characteristics of a Particulate Bone Substitute for Ridge Preservation Procedures

While particulate bone substitute materials are applied in a variety of augmentation procedures, standardized defects are being used for preclinical testing. This in vitro study evaluated the density and homogeneity of a particulate bone substitute in ridge preservation procedures. Premolars and molars were extracted in ten semimandibles of minipig cadavers. Light body impression material was used for determining the volume of the extraction sites followed by augmentation with particulate material, thereby weighing the graft material needed. Microradiographs and histologic sections were obtained for evaluating the homogeneity and density of the augmentation material. Statistical analyses were based on Shapiro-Wilk tests, Spearman's rho and one sample Wilcoxon test followed by Bonferroni-Holm correction for multiple testing (α = 0.05). Based on 103 single alveoli evaluated, the mean volume determined was 0.120 cm3 requiring a mean amount of graft material of 0.155 g. With only three exceptions, all parameters (volume, mass of augmentation material, density and homogeneity) correlated significantly (p < 0.020). The apical parts of the alveoli showed reduced density as compared to the middle parts (p < 0.001) and the homogeneity of the augmentation material was also lower as compared to the middle (p < 0.001) and cervical parts (p Collapse

Key Words

• alveolar ridge augmentation
• bone substitute materials
• ridge preservation

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MESH Headings Collapse

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Affiliation(s)

Samira Dahl
Virgilia Klär-Quarz
Annika Schulz
Matthias Karl
Tanja Grobecker-Karl Department of Prosthodontics, Saarland University, 66421 Homburg, Saar, Germany; (S.D.); (V.K.-Q.); (A.S.); (M.K.)

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Alveolar Ridge Preservation with a Novel Cross-Linked Collagen Sponge: Histological Findings from a Case Report

Alveolar ridge preservation (ARP) is a well-documented procedure to maintain bone volume after tooth extraction in order to place implants. However, at the end of the healing process, the residual biomaterial that is not reabsorbed remains embedded in the bone over time. Ribose cross-linked biomaterials demonstrated their ability to promote osteoconduction and complete resorption. The aim of this study was to evaluate the histological healing pattern of a novel ribose cross-linked collagen sponge used as a grafting material left exposed in human sockets at the time of tooth extraction. On a single patient, non-restorable lower first molars were extracted on both sides, and a ribose cross-linked collagen sponge was placed bilaterally in the cavities and left uncovered at the end of the surgery. After six months, core biopsies were taken immediately prior to implant placement; after the sample preparation, a histological analysis was performed. The results are very promising for substitution with newly formed bone and the amount of residual material. Ribose cross-linked collagen sponge could represent a valid alternative to conventional biomaterials for ARP procedures with no need for flap advancement and/or the addition of a membrane to cover the graft, reducing the invasiveness, complexity, and costs of the treatment.

Alveolar ridge preservation in sockets with severe periodontal destruction using autogenous partially demineralized dentin matrix: A randomized controlled clinical trial

BACKGROUND

The preservation and reconstruction of alveolar ridge volume in extraction sockets of molars affected by severe periodontitis is a critical challenge that requires clinical attention.

PURPOSE

This randomized controlled clinical trial was designed to evaluate the efficiency of autogenous partially demineralized dentin matrix (APDDM) for alveolar ridge preservation (ARP) in severely periodontally compromised sockets compared to spontaneous healing (SH) on radiographic and histomorphometric outcomes.

MATERIALS AND METHODS

Thirty-two patients with 32 periodontally compromised molars were randomized into either the test group, which received ARP using APDDM covered with a collagen sponge, or the control group, which underwent SH. Linear and volumetric changes were assessed using superimposed cone-beam computed tomography (CBCT) acquired pre-extraction and after a 4-month healing time. Histomorphometric evaluation was performed on trephine cores harvested during implant placement.

RESULTS

All sites healed uneventfully. The ridge width at 1 mm apical to the bone crest increased by 5.03, 4.50, and 5.20 mm in the mesial, middle, distal area in the APDDM group, while decreasing by -1.98, -2.19, and -1.98 mm in the SH group, respectively (p < 0.05). The height increase of the central bone was significantly higher in the APDDM group than in the SH group (p < 0.05). The height decrease of the buccal (mesial, middle, distal) bone plate was lower in the APDDM group than in the SH group (p < 0.05). After a 4-month healing time, bone volume increased by 37.07% in the APDDM group and by only 2.33% in the SH group (p < 0.05). Histomorphometric analysis revealed that APDDM particles were surrounded by newly formed bone, with partially absorbed residual APDDM materials observed. New bone, APDDM remnants, and connective tissue occupied 39.67 ± 8.28%, 23.66 ± 9.22%, and 36.67 ± 17.05% of the areas in the APDDM group, respectively.

CONCLUSIONS

ARP using APDDM was effective, resulting in a significant increase in both linear and volumetric changes in severely periodontally compromised extraction sockets compared to SH. These findings suggest that APDDM may serve as a promising new clinical option for the reconstruction of alveolar ridge dimensions.

Prevalence of peri-implantitis after alveolar ridge preservation at periodontitis and nonperiodontitis extraction sites: A retrospective cohort study

INTRODUCTION

Periodontitis is the main indication for dental extraction and often leads to peri-implantitis (PI). Alveolar ridge preservation (ARP) is an effective means of preserving ridge dimensions after extraction. However, whether PI prevalence is lower after ARP for extraction after periodontitis remains unclear. This study investigated PI after ARP in patients with periodontitis.

MATERIALS AND METHODS

This study explored the 138 dental implants of 113 patients. The reasons for extraction were categorized as periodontitis or nonperiodontitis. All implants were placed at sites treated using ARP. PI was diagnosed on the basis of radiographic bone loss of ≥3 mm, as determined through comparison of standardized bitewing radiographs obtained immediately after insertion with those obtained after at least 6 months. Chi-square and two-sample t testing and generalized estimating equations (GEE) logistic regression model were employed to identify risk factors for PI. Statistical significance was indicated by p < 0.05.

RESULTS

The overall PI prevalence was 24.6% (n = 34). The GEE univariate logistic regression demonstrated that implant sites and implant types were significantly associated with PI (premolar vs. molar: crude odds ratios [OR] = 5.27, 95% confidence intervals [CI] = 2.15-12.87, p = 0.0003; bone level vs. tissue level: crude OR = 5.08, 95% CI = 2.10-12.24; p = 0.003, respectively). After adjustment for confounding factors, the risks of PI were significantly associated with implant sites (premolar vs. molar: adjusted OR [AOR] = 4.62, 95% CI = 1.74-12.24; p = 0.002) and implant types (bone level vs. tissue level: AOR = 6.46, 95% CI = 1.67-25.02; p = 0.007). The reason for dental extraction-that is, periodontitis or nonperiodontitis-was not significantly associated with PI.

CONCLUSION

ARP reduces the incidence of periodontitis-related PI at extraction sites. To address the limitations of our study, consistent and prospective randomized controlled trials are warranted.

Effect of alveolar ridge preservation on peri-implant mucositis and peri-implantitis prevalence: A multicenter, cross-sectional study

OBJECTIVES

Alveolar ridge preservation (ARP) is a procedure with the aim to reduce bone resorption that occurs after tooth extraction, facilitating the following implant placement. The aim of this cross-sectional study was to evaluate the prevalence of mucositis and peri-implantitis around implants inserted in sites treated with ARP and to investigate possible risk factors.

MATERIALS AND METHODS

Patients who received at least one dental implant inserted in a grafted socket were considered eligible for this study. Patients were recalled for a follow-up visit; medical history, clinical and demographic data were collected. Univariate logistic regression analyses have been performed for both implant-level and patient-level variables. Indeed, moderation analysis was used to investigate the indirect relationship between age and marginal bone level.

RESULTS

Fifty-one patients who received 61 implants were enrolled in this cross-sectional study. Thirty-three implants were classified as "healthy" (54.1%), 23 implants showed signs of peri-implant mucositis (37.7%), and 5 implants were diagnosed with peri-implantitis (8.2%). Data analyzed at the patient level showed that 49% of the patients were healthy, 45.1% of the patients had mucositis and 5.9% of the patients were affected by peri-implantitis. Mandibular sites and type III grafted sockets showed a significant association with peri-implantitis; in addition, a history of periodontitis and an increase in age showed higher risks of developing mucositis or peri-implantitis.

CONCLUSIONS

Implants inserted in grafted sockets showed favorable rates of healthy implants in the long term.

CLINICAL RELEVANCE

The ridge preservation procedures do not seem to increase the risk of developing mucositis or peri-implantitis.

Biomaterials for Alveolar Ridge Preservation as a Preoperative Procedure for Implant Treatment: History and Current Evidence

In implant treatment, the reduction and structural changes in the alveolar ridge that occur after tooth extraction limit the length, width, and placement position of the implant body, impair esthetics, and, in some cases, make implant placement difficult. To solve these problems, an alveolar ridge preservation (ARP) technique, which is performed simultaneously with tooth extraction, generally aims to promote bone regeneration and prevent alveolar ridge reduction by filling the extraction socket with bone graft material and then covering it with a barrier membrane to protect against the invasion of epithelial tissue. The extraction socket provides a favorable environment for bone regeneration throughout the healing period because the blood supply is abundant, and it effectively retains the bone graft material by using the remaining bone wall of the socket. In recent years, advances in bioengineering technology have led to the development of graft materials with various biological properties, but there is currently no clear consensus regarding the selection of surgical techniques and materials depending on the condition of the alveolar ridge. This review will provide a comprehensive survey of the evidence accumulated to date on ARP, present many cases according to the clinical situation, and discuss various treatment options.

Radiographic comparison of atelocollagen versus deproteinized bovine bone minerals covered with a collagen membrane in alveolar ridge preservation: a retrospective study

BACKGROUND

Atelocollagen (AC) is a low-immunogenic collagen derivative with longer degradation time, which can be a suitable material for alveolar ridge preservation (ARP). However, there are few human studies on AC using for ARP. This research aims to radiographically evaluate the efficacy of AC in comparison to deproteinized bovine bone minerals covered with a collagen membrane (DBBM/CM) in ARP.

METHODS

Medical records in the Implantology Department of the Hospital of Stomatology of Wuhan University were screened for patients who received flapless ARP using either AC or DBBM/CM. A total of 58 patients were included in this retrospective study. 28 patients were treated with AC, while 30 patients were used DBBM/CM. Cone-beam computed tomography (CBCT) scans were taken before extraction and after 6 months of healing. To assess the dimensional change of the extraction sockets, the scanning data were output and transferred to the digital software to measure horizontal bone width change, vertical bone height change and bone volume change in region of interest. To evaluate the bone quality of healed sockets, the bone density of virtual implants was evaluated.

RESULTS

The horizontal bone width changes at all five different levels showed no significant difference between the two groups. The largest horizontal bone width decrement in both groups occurred at the crest of ridge, which decreased 3.71 ± 1.67 mm in AC group and 3.53 ± 1.51 mm in DBBM/CM group (p = 0.68). At the central buccal aspect, the ridge height reduced 0.10 ± 1.30 mm in AC group, while increased 0.77 ± 2.43 mm in DBBM/CM group (p = 0.10). The vertical bone height differences between two groups showed no statistical significance. The percentages of volume absorption in AC group and DBBM/CM group were 12.37%±6.09% and 14.54%±11.21%, respectively. No significant difference in volume absorption was found (p = 0.36). The average bone density around virtual implants in AC group (649.41 ± 184.71 HU) was significantly lower than that in DBBM/CM group (985.23 ± 207.85 HU) (p < 0.001).

CONCLUSIONS

ARP with AC had a similar effect on limiting the dimensional alteration of alveolar ridge, when radiographically compared with DBBM/CM.

A Socket Seal Technique With the Use of Autologous Dental Roots for Socket Seal: A Case Series

The literature identified variations in socket seal surgery, each with limitations. This case series aimed to observe the outcome of using autologous dental root (ADR) for socket sealing on socket preservation (SP). A total of 9 patients with 15 extraction sockets were documented. After flapless extraction, the xenograft or alloplastic grafts were placed in the sockets. Autologous dental roots were prepared extraorally and applied to seal the socket entrance. All SP sites healed uneventfully. Cone-beam computed tomography (CBCT) scan was performed after 4-6 months of healing to evaluate ridge dimensions. The preserved alveolar ridge profiles were verified on CBCT scans and during implant surgery. Implants were placed successfully with a reduced need for guided bone regeneration. Histological biopsy specimens were examined in 3 cases. The histological examination demonstrated vital bone formation and osseointegration of graft particles. All patients completed the final restorations and were monitored for 15.56 ± 9.08 months after functional loading. The favorable clinical outcomes support the use of ADR for SP procedures. It was not only accepted to patients but also easy to perform with low complication rates. The ADR technique is thus a feasible method for socket seal surgery.

Is alveolar ridge preservation an overtreatment?

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

The effect of recurrent application of concentrated platelet-rich fibrin inside the extraction socket on the hard and soft tissues. a randomized controlled trial

Background

Platelet-rich fibrin (PRF) is commonly used for ridge preservation following tooth extraction. However, its effectiveness diminishes over a period of two weeks as it is resorbed and loses its biological activities. Therefore, this clinical study aims to evaluate the effect of recurrent application of concentrated PRF (C-PRF) inside the extraction socket on the hard and soft tissue alterations.

Methods

Twenty patients requiring single tooth extraction and replacement with a dental implant were randomized into one of two ridge preservation approaches: Advanced PRF plus alone (Control group) or advanced PRF plus with the recurrent application of a C-PRF inside the socket every two weeks for 2 months (four times). The ridge width, the ridge height, and the soft tissue thickness were assessed clinically at the baseline and reassessed after 3 months from tooth extraction during implant surgery. Then the amount of hard tissue loss and soft tissue alterations were calculated.

Results

There was a statistically significant difference in the amount of hard tissue loss between groups in the third month. The amount of horizontal ridge loss for the control and test groups were 2.9 ± 0.7 mm and 1.9 ± 0.5 mm, respectively (p-value < 0.05). The vertical bone loss for control and test groups were 1.8 ± 0.5 mm and 1.0 ± 0.3 mm, respectively (p-value < 0.05). Additionally, for the soft tissue thickness, there was no statistical difference between the groups (p-value > 0.05).

Conclusion

Within the limitations of this study, the recurrent application of C-PRF in the extraction socket could decrease the amount of ridge alteration following tooth extraction and may play a role in the bone regeneration procedures.

Trial registration

Registered on ClinicalTrials.gov (ID: NCT05492357, on 08/08/2022).

The effect of recurrent application of concentrated platelet-rich fibrin inside the extraction socket on the hard and soft tissues. a randomized controlled trial

BACKGROUND

Platelet-rich fibrin (PRF) is commonly used for ridge preservation following tooth extraction. However, its effectiveness diminishes over a period of two weeks as it is resorbed and loses its biological activities. Therefore, this clinical study aims to evaluate the effect of recurrent application of concentrated PRF (C-PRF) inside the extraction socket on the hard and soft tissue alterations.

METHODS

Twenty patients requiring single tooth extraction and replacement with a dental implant were randomized into one of two ridge preservation approaches: Advanced PRF plus alone (Control group) or advanced PRF plus with the recurrent application of a C-PRF inside the socket every two weeks for 2 months (four times). The ridge width, the ridge height, and the soft tissue thickness were assessed clinically at the baseline and reassessed after 3 months from tooth extraction during implant surgery. Then the amount of hard tissue loss and soft tissue alterations were calculated.

RESULTS

There was a statistically significant difference in the amount of hard tissue loss between groups in the third month. The amount of horizontal ridge loss for the control and test groups were 2.9 ± 0.7 mm and 1.9 ± 0.5 mm, respectively (p-value < 0.05). The vertical bone loss for control and test groups were 1.8 ± 0.5 mm and 1.0 ± 0.3 mm, respectively (p-value < 0.05). Additionally, for the soft tissue thickness, there was no statistical difference between the groups (p-value > 0.05).

CONCLUSION

Within the limitations of this study, the recurrent application of C-PRF in the extraction socket could decrease the amount of ridge alteration following tooth extraction and may play a role in the bone regeneration procedures.

TRIAL REGISTRATION

Registered on ClinicalTrials.gov (ID: NCT05492357, on 08/08/2022).

Clinical and radiographic assessment of cross-linked hyaluronic acid addition in demineralized bovine bone based alveolar ridge preservation: A human randomized split-mouth pilot study

PURPOSE

To investigate clinically and radiographically at 4 months post-operatively the outcomes of mixing demineralized bovine bone material (DBBM) with cross-linked hyaluronic acid in alveolar ridge preservation.

MATERIAL AND METHODS

Seven patients presenting bilateral hopeless teeth (14 teeth) were enrolled in the study, the test site contained demineralized bovine bone material (DBBM) mixed with cross-linked hyaluronic acid (xHyA) while the control site contained only DBBM. 4 months post-operatively prior to implant placement a Cone beam computed tomography (CBCT) scan was recorded and compared to the initial scan to assess the volumetric and linear bone resorption that occurred in both sites. Clinically, sites that needed further bone grafting at the implant placement stage were recorded. Differences in volumetric and linear bone resorption between both groups were assessed using Wilcoxon signed rank test. McNemar test was also used to evaluate difference in bone grafting need between both groups.

RESULTS

All sites healed uneventfully, volumetric and linear resorption differences between the baseline and 4 months post-operatively were obtained for each site. The mean volumetric and linear bone resorption were respectively 36.56 ± 1.69%, 1.42 ± 0.16 mm in the controls sites and 26.96 ± 1.83%; 0.73 ± 0.052 mm in the tests sites. The values were significantly higher among controls sites (P=0.018). No significant differences were observed in the need for bone grafting between both groups.

CONCLUSION

Cross-linked hyaluronic acid (xHyA) appears to limit the post-extractional alveolar bone resorption when mixed with DBBM.

Extraction Socket Augmentation with Autologous Platelet-Rich Fibrin (PRF): The Rationale for Socket Augmentation

After tooth extraction, the alveolar ridge undergoes a physiological process of remodelling and disuse atrophy. Socket augmentation (SA) has been shown to preserve alveolar bone volume in order to facilitate implant placement and reduce the need for staged grafting at a later date. Although autogenic grafting has been shown to be the gold standard in bone regeneration, it has significant disadvantages. To prevent post-extraction volumetric alterations and alveolar bone resorption occurring, alternative grafting materials, including xenografts, alloplasts, and allografts, have been used successfully in fresh extraction sites. However, these materials act mostly as bio-scaffolds and require a slower integration period of 6-8 months prior to implant placement. Recently, the use of autologous platelet-rich fibrin (PRF) has been advocated alongside socket augmentation as a method of bio-enhancement of healing of soft and hard tissues. PRF contains platelet-derived growth factors, hormones, and bioactive components such as cytokines that have been shown to promote angiogenesis and tissue regeneration during wound healing. The aim of this article is to review the evidence base for the SA technique Clinical benefits of SA will be discussed with a reference to two cases. Therefore, this narrative review will discuss the post-extraction bone changes, the importance of SA, and the bio-enhancement role of PRF in the management of extraction site defects when the alternative technique of immediate implant placement is not possible or contraindicated.

Enamel matrix derivative for alveolar ridge preservation: A randomized controlled trial

OBJECTIVE

The aims of this clinical trial were to evaluate the radiographic dimensional changes in alveolar ridge and patient-reported outcomes following tooth extraction and alveolar ridge preservation (ARP) using either deproteinized bovine bone mineral (DBBM) with EMD or DBBM alone.

METHODS

Participants requiring at least one posterior tooth extraction and ARP were randomly allocated into two treatment groups: ARP using either DBBM with EMD or DBBM alone. Cone-beam computed tomography (CBCT) images were recorded immediately prior to extraction and at 6 months. Changes in alveolar ridge height (ARH) and alveolar ridge width (ARW) at 1, 3, and 5 mm were recorded.

RESULTS

A total of 18 participants with 25 preserved sites were evaluated. ARH and ARW changed significantly from baseline to 6 months for both treatment groups but the difference between the groups was not statistically significant over the 6-month follow-up period (ARH: DBBM/EMD 1.26 ± 1.53 mm vs. DBBM 2.26 ± 1.60 mm; ARW-1 DBBM/EMD 1.98 ± 1.80 mm vs. DBBM 2.34 ± 1.89 mm). A significant difference, favoring DBBM with EMD group, was observed in percentage of sites that had less than 1 mm loss in ARH (54.5% sites in DBBM/EMD group vs. 14.3% sites in DBBM alone group). The participants' perception of bruising, bleeding, and pain in the first two postoperative days was significantly in favor of DBBM alone group.

CONCLUSIONS

There were no significant differences in radiographic mean measurements of ARH and ARW following ARB with DBBM and EMD or DBBM alone.

Alveolar Bone Preservation Using a Combination of Nanocrystalline Hydroxyapatite and Injectable Platelet-Rich Fibrin: A Study in Rats

Alveolar bone resorption is a post-extraction complication wherein there is a reduction in the dimensions and quality of the alveolar bone. This study aimed to examine the effects of implantation of a combination of nanocrystalline hydroxyapatite (nHA) and injectable platelet-rich fibrin (IPRF) on the expression of tartrate-resistant acid phosphatase (TRAP), alkaline phosphatase (ALP), osteocalcin (OCN), and new bone formation. A total of 32 male rats had their upper right incisors extracted under general anesthesia and were then divided into a control group, nHA group, IPRF group, and nHA-IPRF group. Decapitation was carried out on day 14 and day 28 in each group and the jaws of each rat were subjected to immunohistochemical and histological analysis. The results showed a decrease in TRAP expression in the nHA-IPRF group compared with the control group on day 14 (p = 0.074) and day 28 (p = 0.017). The study also showed an increase in ALP and OCN in the HA-IPRF group on day 14 and day 28 compared with the control group. New bone formation suggested a significant increase in the nHA-IPRF group compared with the control group on day 14 (p = 0.001) and day 28 (p = 0.001). nHA-IPRF implantation can suppress alveolar bone resorption, which is indicated by decreased TRAP expression, and it can increase bone growth, as indicated by increased expression of ALP, OCN, and new bone formation.

The Effect of Terra-Cortril as Local Pain Medication on the Healing Process of a Fresh Extraction Socket: A Retrospective Cohort Study

(1) Background: Use of Terra-Cortril may reduce pain and discomfort after tooth extraction. It is widely used among dentists, especially for third molar extraction and for treatment of dry socket. Only few case reports described unsuccessful healing with formation of myospherulosis. (2) Aim: The primary objective of this retrospective cohort study was to compare the occurrence of unsuccessful healing between extraction sockets locally treated with Terra-Cortril (TC) (exposure cohort) and extraction sockets subjected to unassisted healing (non-exposure cohort). The assessment of the three-dimensional morphology of the bone was a secondary objective. (3) Material and methods: The records of patients who had one or more extractions between 1 January 2020 and 1 July 2021 followed by implant placement in one private practice were retrieved and data were extracted. At the time of implant placement, practitioners established, both clinically and radiographically, if the healing was successful or unsuccessful. Explanatory demographic as well as clinical variables were extracted from patient files, checked and supplemented by contacting patients in cases of missing data. (4) Results: 69 patients were included who had, in total, 99 extractions. The exposure cohort included 55 sites, while the non-exposure cohort included 44 sites. A total of 56 sites demonstrated successful healing, and 53 showed unsuccessful healing. The regression model identified TC as a significant predictor (p = 0.014) for unsuccessful healing with an odds ratio of 2.86. Sites treated with Terra-Cortril had a significantly greater bone defect at level -1 mm, level -3 mm, and level -5 mm from the bone crest, and significantly greater maximal vertical and horizontal bone defects. At sites where Terra-Cortril was used, significantly more surgical consequences were reported (70.91% vs. 18.18%, p < 0.001). (5) Conclusions: fresh extraction sockets treated with Terra-Cortril increased the likelihood of unsuccessful healing with an odds ratio of 2.86. The greater defect size leads to significantly more limitations when planning implants at sites previously treated with TC.

Errors and complications in clinical periodontal practice due to methodologic bias and bad interpretation of the evidence

Different types of errors and complications may arise during and after the execution of periodontal or implant-related procedures. Some of the most relevant, although also controversial, and less commented, causative agents of errors and complications are methodological biases and bad interpretation of the evidence. Proper assessment of the literature requires of solid clinical knowledge combined with a systematic approach built on the recognition of common methodological biases and the avoidance of interpretive errors to critically retrieve, dissect, and judiciously apply available information for the promotion of periodontal and peri-implant health. This review addresses common types of methodological bias and interpretive errors that can alter the reader's perceptions on the real effect and potential ramifications of the reported outcomes of a given therapeutic approach due to bad interpretation of the available evidence: (1) types of methodological biases; (2) spin and interpretive bias; (3) interpretation pitfalls when assessing the evidence (4) choice of relevant endpoints to answer the question(s) of interest; and (5) balance between statistical significance and clinical relevance.

Alveolar ridge preservation: Complications and cost-effectiveness

Alveolar ridge preservation is routinely indicated in clinical practice with the purpose of attenuating postextraction ridge atrophy. Over the past two decades numerous clinical studies and reviews on this topic have populated the literature. In recent years the focus has primarily been on analyzing efficacy outcomes pertaining to postextraction dimensional changes, whereas other relevant facets of alveolar ridge preservation therapy have remained unexplored. With this premise, we carried out a comprehensive evidence-based assessment of the complications associated with different modalities of alveolar ridge preservation and modeled the cost-effectiveness of different therapeutic modalities as a function of changes in ridge width and height. We conclude that, among allogeneic and xenogeneic bone graft materials, increased expenditure does not translate into increased effectiveness of alveolar ridge preservation therapy. On the other hand, a significant association between expenditure on a barrier membrane and reduced horizontal and vertical ridge resorption was observed, though only to a certain degree, beyond which the return on investment was significantly diminished.

Alveolar ridge preservation: A review of concepts and controversies

The loss of thickness and height of the alveolar process after tooth extraction is a significant impediment to implant placement, which limits the aesthetic results of many restorative treatments. Alveolar ridge preservation can reduce bone resorption. Knowing how beneficial this procedure is can help clinicians decide if it is worth doing. The purpose of this article is to present a contemporary review of the different approaches to preserving the dimensions of the alveolar ridge. We analyze the alveolar healing process, atraumatic extraction techniques, graft materials, and controversies.

Anterior Maxillary Labial Bone Thickness on Cone Beam Computed Tomography

AIM

The objective of this research was to measure the labial bone thickness (LBT) in relation to the 6 anterior maxillary teeth at different levels along the long axis and the distance between cementoenamel junction and bone crest (CEJ-BC) based on cone beam computed tomography (CBCT) scans retrieved from patients of Arab ethnicity and identify any association with patients' characteristics.

MATERIALS AND METHODS

A total of 100 CBCT scans were evaluated by one calibrated examiner. The thickness of the labial bone was measured perpendicular to the long axis of the tooth at 1, 3, and 5 mm from the alveolar crest (LBT-1, LBT-3, and LBT-5, respectively) and CEJ-BC using a medical imaging viewer.

RESULTS

CBCT scans of 58 female patients and 42 male patients with a mean age of 39.7 ± 9.5 years were included. A high variation of CEJ-BC was observed (range, 0.55-3.90 mm). Statistically significant higher CEJ-BC values were associated with men and increased age (>50 years). The overall means of LBT-1 were 0.76 ± 0.26, 0.79 ± 0.26, and 0.83 ± 0.37 mm; LBT-3: 0.92 ± 0.36, 1.05 ± 0.46, and 1.03 ± 0.48 mm; LBT-5: 1.17 ± 0.52, 0.80 ± 0.45, and 0.81 ± 0.40 mm for central incisors, lateral incisors, and canines, respectively. The LBT was <1 mm in 74.2% of all maxillary anterior teeth, with central incisors showing the highest predilection (85% with LBT <1 mm). No significant association between LBT and patient characteristics was observed.

CONCLUSIONS

The CEJ-BC distance is greater in men and increases with age, particularly in those aged 50 years and older. The LBT in the 6 maxillary anterior teeth is predominantly thin (<1 mm) and has no correlation to age or sex. An increased LBT was observed at a 3-mm level when compared with LBT-1 and LBT-5. Such variability should be taken into consideration when planning for implant placement.

Influence of partially exposed nonabsorbable membrane for alveolar ridge preservation: A randomized controlled trial

AIM

This randomized controlled trial evaluated the impact of a partially exposed non-absorbable membrane (dPTFE) in Alveolar Ridge Preservation (ARP) procedures on clinical, tomographic, immunoenzymatic, implant-related, and patient-centered outcomes.

MATERIALS AND METHODS

Patients with a hopeless maxillary single-rooted tooth demanding rehabilitation with implants were included. Patients were randomized into two groups: dPTFE (n = 22)-tooth extraction followed by ARP using a partially exposed dPTFE membrane; USH (n = 22)-unassisted socket healing. Clinical and tomographic analyses were performed at baseline and after 3 months. After 3 months, patients received one dental implant. Implant stability quotient was obtained following implant placement. Bone-related markers were analyzed in bone biopsies using an immunoenzymatic assay.

RESULTS

Greater gain in Keratinized Mucosa Width (KMW) was observed in the dPTFE (1.33 ± 0.98 mm) compared to USH (0.59 ± 0.98 mm) (Mann-Whitney test, Z = 2,28, p < 0.05). USH showed a reduction of pain/discomfort, edema, and interference with daily life from the seventh day (Friedman/Wilcoxon test, maxT = 7.48, 8.00, and 5.92, respectively, p < 0.05). dPTFE presents a reduction of edema and interference with daily life from the 7th day and pain/discomfort from the 14th day (Friedman/Wilcoxon test, maxT = 5.40, 5.26, and 4.78, respectively, p < 0.05). The dPTFE group presented higher pain/discomfort in the 35 and 42 days and higher edema from 7 to 42 days postoperatively than USH group (Mann-Whitney test, p < 0.05). No differences between groups were observed in the tomographic measures, immunoenzymatic analysis, and implant stability (p > 0.05).

CONCLUSION

dPTFE was superior to USH by increasing KMW gain. However, dPTFE without bone graft presented similar bone loss compared to USH. This clinical trial was not registered prior to participant recruitment and randomization (NCT04329351).

Comparative Effects of Different Materials on Alveolar Preservation

OBJECTIVE

The purpose of this study was to compare different materials' effects on alveolar ridge preservation of postextraction sockets in anterior maxilla.

MATERIALS AND METHOD

In this prospective, single center, randomized, controlled clinical trial, healthy patients who needed one single anterior maxillary tooth extraction (including bicuspids) were selected. After a minimally traumatic extraction without complications, 44 patients were randomly allocated into 4 groups: 1) natural socket healing (blood clot), 2) xenograft and gingival free graft, 3) dense polytetrafluoroethylene membrane, and 4) platelet rich fibrin plugs. Alveolar ridge height and width loss were evaluated in cone beam computed tomography (CBCT) and in dental casts at 3 moments: 1) preoperative (T1), 2) 7 days postoperative (T2), and 3) 120 days postoperative (T3). Height and width alveolar ridge loss detected in CBCT and in dental casts were compared among the groups (two-way analysis of variance [ANOVA]; P < .05).

RESULTS

Forty patients (24 women and 16 men) ranging from 25 to 70 years old (mean of 42 years old) participated in this study. Group 2 showed the least alveolar ridge height loss results in CBCT (9.8 ± 1.9% at T3) and dental cast analysis (1.0 ± 0.2 mm). Groups 2 (12.7 ± 4.7% at T3) and 3 (15.4 ± 2.7% at T3) showed the least alveolar ridge width loss measured in CBCT compared with groups 1 and 4, but the difference between groups 2 and 3 were not statistically significant (P = .968). Group 3 (0.9 ± 0.2 mm) and group 2 (1.0 ± 0.2 mm) showed the least width loss compared with groups 1 and 4 in dental cast analysis. Again, the difference between groups 3 and 2 was not statistically significant (P = 1.000).

CONCLUSION

In postextraction sockets of the anterior maxilla and bicuspid region, group 2 (xenogenous bone graft with free gingival graft) and group 3 (dense polytetrafluoroethylene) obtained the best results in alveolar preservation, with group 2 being more indicated when the vertical alveolar ridge preservation is mandatory.

Influence of healing time on the outcomes of alveolar ridge preservation using a collagenated bovine bone xenograft: A randomized clinical trial

AIM

To evaluate the healing outcomes in non-molar post-extraction sockets filled with deproteinized bovine bone mineral with collagen (DBBM-C) as a function of time.

MATERIALS AND METHODS

Patients in need of non-molar tooth extraction were randomly allocated into one of three groups according to the total healing time (A-3 months; B-6 months; C-9 months). The effect of alveolar ridge preservation (ARP) therapy via socket filling using DBBM-C and socket sealing with a porcine collagen matrix (CM) was assessed based on a panel of clinical, digital, histomorphometric, implant-related, and patient-reported outcomes.

RESULTS

A total of 42 patients completed the study (n = 14 in each group). Histomorphometric analysis of bone core biopsies obtained at the time of implant placement showed a continuous increase in the proportion of mineralized tissue with respect to non-mineralized tissue, and a decrease in the proportion of remaining xenograft material over time. All volumetric bone and soft tissue contour assessments revealed a dimensional reduction of the alveolar ridge overtime affecting mainly the facial aspect. Linear regression analyses indicated that baseline buccal bone thickness is a strong predictor of bone and soft tissue modelling. Ancillary bone augmentation at the time of implant placement was needed in 16.7% of the sites (A:2; B:1; C:4). Patient-reported discomfort and wound healing index scores progressively decreased over time and was similar across groups.

CONCLUSIONS

Healing time influences the proportion of tissue compartments in non-molar post-extraction sites filled with DBBM-C and sealed with a CM. A variable degree of alveolar ridge atrophy, affecting mainly the facial aspect, occurs even after performing ARP therapy. These changes are more pronounced in sites exhibiting thin facial bone (≤1 mm) at baseline (Clinicaltrials.gov NCT03659617).

Clinical evaluations of alveolar ridge preservation in compromised extraction sockets with cortical-lamina anchoring technique: Case series study

OBJECTIVE

The objective of this study is to retrospectively evaluate the clinical outcomes of alveolar ridge preservation (ARP) in the compromised extraction sockets using autogenous cortical-lamina anchoring technique (CAT).

MATERIAL AND METHODS

Twenty patients were treated with ARP in the compromised extraction sockets by applying CAT. Then implant placement and crown delivery was performed. A planned follow-up was performed by analyzing various outcome measures to evaluate the clinical outcomes, including primary outcome measures [radiographic assessment of residual alveolar ridge height (RARH) and residual alveolar ridge width (RARW)] and secondary outcome measures [clinical assessment of the healing of the soft and hard tissue, survival rates of implants, marginal bone loss (MBL) evaluation of implants, buccal bone thickness (BBT), and esthetic treatment outcomes].

RESULTS

Among the 20 patients, 17 were consecutively treated and 3 dropped out after implant crown delivery because of loss to follow-up. After the ARP, the initial RARH (12.37 mm) significantly increased to 19.29 mm (P < .05). No significant difference was detected in the RARW before (7.92 ± 1.18 mm) and after (7.92 ± 1.18 mm) the ARP, but reduce to 6.99 ± 1.18 mm at the implant placement and 6.64 ± 0.77 mm at the 3-year follow-up (P < .05). The MBL at the implant crown delivery (0.13 ± 0.12 mm) significantly increased to 0.31 ± 0.14 mm at 1-year follow-up and 0.56 ± 0.23 mm at 3-year follow-up, respectively. The bone loss was limited (<1 mm) but statistically significant (P < .05). The BBT at the implant placement (2.53 ± 0.56 mm) significantly reduced to 2.23 ± 0.44 mm at implant crown delivery and 2.14 ± 0.40 mm at 3-year follow-up, respectively. The bone loss was also limited (<0.5 mm) but statistically significant (P < .05). Each implant site showed acceptable aesthetic outcome and the average score was 16.4. The incisions healed uneventful in all patients and the implant survival rate was 100% during the 3-year follow-up.

CONCLUSION

Autogenous CAT was successfully applied to preserve the height and width of alveolar ridge in the compromised extraction sockets.

A three-dimensional actively spreading bone repair material based on cell spheroids can facilitate the preservation of tooth extraction sockets

Introduction: Achieving a successful reconstruction of alveolar bone morphology still remains a challenge because of the irregularity and complex microenvironment of tooth sockets. Biological materials including hydroxyapatite and collagen, are used for alveolar ridge preservation. However, the healing effect is often unsatisfactory. Methods: Inspired by superwetting biomimetic materials, we constructed a 3D actively-spreading bone repair material. It consisted of photocurable polyether F127 diacrylate hydrogel loaded with mixed spheroids of mesenchymal stem cells (MSCs) and vascular endothelial cells (ECs). Results: Biologically, cells in the spheroids were able to spread and migrate outwards, and possessed both osteogenic and angiogenic potential. Meanwhile, ECs also enhanced osteogenic differentiation of MSCs. Mechanically, the excellent physical properties of F127DA hydrogel ensured that it was able to be injected directly into the tooth socket and stabilized after light curing. In vivo experiments showed that MSC-EC-F127DA system promoted bone repair and preserved the shape of alveolar ridge within a short time duration. Discussion: In conclusion, the novel photocurable injectable MSC-EC-F127DA hydrogel system was able to achieve three-dimensional tissue infiltration, and exhibited much therapeutic potential for complex oral bone defects in the future.

Modified Tunnel Procedure to Facilitate Ridge Reconstruction of an Extraction Socket Associated with Buccal Dehiscence and Gingival Recession: A Case Report with a 6-year Follow-Up

Introduction

Extraction sockets associated with buccal dehiscences and gingival recessions pose particular surgical and restorative challenges. In these cases, unassisted healing following flapless tooth extraction results in severe bone and soft tissue deformities and an aesthetic compromise. Root coverage procedures prior to ridge reconstruction may enable predictable alveolar augmentation. Case Presentation. This is the first case report describing the utilisation of modified tunnel procedure to facilitate ridge reconstruction consisting of ovate pontic and xenograft, of tooth #25 in a 38-year-old-male. The 6 months and 1-year reviews showed optimal soft tissue aesthetics, 100% root coverage of the tooth #25, and bone augmentation, which enabled placement of 10.0 mm × 4.0 mm (3i) implant in a prosthetically driven position. The 6-year review continued to show favourable clinical outcomes.

Conclusion

Compromised extraction sockets containing buccal dehiscence and associated with gingival recessions may benefit from soft tissue augmentation procedures to enhance the clinical outcome of ridge reconstruction.

The current regenerative medicine approaches of craniofacial diseases: A narrative review

Craniofacial deformities (CFDs) develop following oncological resection, trauma, or congenital disorders. Trauma is one of the top five causes of death globally, with rates varying from country to country. They result in a non-healing composite tissue wound as they degenerate in soft or hard tissues. Approximately one-third of oral diseases are caused by gum disease. Due to the complexity of anatomical structures in the region and the variety of tissue-specific requirements, CFD treatments present many challenges. Many treatment methods for CFDs are available today, such as drugs, regenerative medicine (RM), surgery, and tissue engineering. Functional restoration of a tissue or an organ after trauma or other chronic diseases is the focus of this emerging field of science. The materials and methodologies used in craniofacial reconstruction have significantly improved in the last few years. A facial fracture requires bone preservation as much as possible, so tiny fragments are removed initially. It is possible to replace bone marrow stem cells with oral stem cells for CFDs due to their excellent potential for bone formation. This review article discusses regenerative approaches for different types of craniofacial diseases.

Preparation and Characterization of Porous Poly(Lactic Acid)/Poly(Butylene Adipate-Co-Terephthalate) (PLA/PBAT) Scaffold with Polydopamine-Assisted Biomineralization for Bone Regeneration

The development of scaffolds that simultaneously provide porous architectures and osteogenic properties is the major challenge in tissue engineering. Herein, a scaffold with high porosity and well interconnected networks, namely poly(lactic acid)/poly(butylene adipate-co-terephthalate) (PLA/PBAT), was fabricated using the gas foaming/ammonium bicarbonate particulate leaching technique. Mussel-inspired polydopamine (PDA)-assisted biomineralization generated by two-step simple soaking in dopamine solution and 10× SBF-like solution was performed to improve the material's osteogenicity. Highly porous scaffolds available in less organized opened cell structures with diameters ranging from 10 µm to 100 µm and 200 µm to 500 µm were successfully prepared. The well interconnected porous architectures were observed through the whole thickness of the scaffold. The even deposition of the organic-inorganic bioactive mineralized layer composed of PDA and nano-scale hydroxyapatite (HA) crystals on the scaffold surface was evidenced by scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The developed scaffold exhibited high total porosity (84.17 ± 1.29%), a lower surface contact angle (θ = 45.7 ± 5.9°), lower material degradation rate (7.63 ± 2.56%), and a high level of material biocompatibility. The MTT assay and Alizarin Red S staining (ARS) confirmed its osteogenic enhancement property toward human osteoblast-like cells (MG-63). These results clarified that the developed porous PLA/PBAT scaffold with PDA-assisted biomineralization exhibited good potential for application as a biomaterial for bone tissue regeneration and hard tissue engineering.

Antifouling poly(PEGMA) grafting modified titanium surface reduces osseointegration through resisting adhesion of bone marrow mesenchymal stem cells

As an alternative strategy to achieve the desired bone augmentation, tenting screw technology (TST) has considerably broadened the indications for implant treatment. Titanium tenting screws are typically used in TST to maintain the space for bone regeneration. However, a high degree of osteogenic integration complicate titanium tenting screw removal and impact the bone healing micro-environment. Previous efforts have been focused on modifying titanium surfaces to enhance osseointegration while ignoring the opposite process. Due to the vital role of bone marrow mesenchymal stem cells (BMSCs) in bone regeneration, it might be feasible to reduce osseointegration around titanium tenting screws by resisting the adhesion of BMSCs. Herein, poly(ethylene glycol)methyl ether methacrylate (poly(PEGMA)) with an optimal length of PEG chain was incorporated with a Ti surface in terms of surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP). The cell apoptosis analysis showed that the new surface would not induce the apoptosis of BMSCs. Then, the adhesive and proliferative behaviors of BMSCs on the surface were analyzed which indicated that the poly(PEGMA) surface could inhibit the proliferation of BMSCs through resisting the adhesion process. Furthermore, in vivo experiments revealed the presence of the poly(PEGMA) on the surface resulted in a lower bone formation and osseointegration compared with the Ti group. Collectively, this dense poly(PEGMA) surface of Ti may serve as a promising material for clinical applications in the future. STATEMENT OF SIGNIFICANCE: The significance of this research includes: The poly(ethylene glycol)methyl ether methacrylate (poly(PEGMA)) with an optimal length of PEG chain was grafted onto a Ti surface by surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP). The PEGMA surface could reduce the osteogenic integration by preventing the adhesion of cells, resulting in a lower pullout force of the modified implant and thereby desirable and feasible applications in dental surgery.

The Use of Biocompatible Membranes in Oral Surgery: The Past, Present & Future Directions. A Narrative Review

The use of biocompatible membranes in periodontal and oral surgery is an important part of regeneration. Over the years, several different membranes have been developed, ranging from non-resorbable membranes that have to be removed in a separate procedure, to collagen membranes that completely resorb on their own, thus avoiding the need for a second surgery. Autogenous membranes are becoming increasingly popular in more recent years. These membranes can be used with a great variety of techniques in the four main hard tissue regenerative procedures: guided tissue regeneration, alveolar ridge preservation, guided bone regeneration and sinus floor augmentation. A review of the literature was conducted in order to identify the most commonly used membranes in clinical practice, as well as the most promising ones for regeneration procedures in the future. The information provided in this review may serve as a guide to clinicians, in order to select the most applicable membrane for the clinical case treated as the correct choice of materials may be critical in the procedure's success.

The Effect of Coenzyme Q10/Collagen Hydrogel on Bone Regeneration in Extraction Socket Prior to Implant Placement in Type II Diabetic Patients: A Randomized Controlled Clinical Trial

Background: The healing of an extraction socket leads to alveolar ridge resorption that can hinder future implant placement and further rehabilitation with special concerns in diabetes mellitus. Coenzyme Q10 (CoQ10) has been developed as a new material for alveolar socket augmentation. The aim of this study was to investigate the effect of CoQ10 hydrogel on bone regeneration after extraction of mandibular teeth in Type II diabetic patients. Methods: This trial was registered under the number NCT05122299 and included eighteen patients. The hydrogel was first prepared and characterized. After tooth extraction, the hydrogel was placed in the extraction sockets. Bone formation was evaluated three months after tooth extraction. Results: The bone density was significantly higher in the CoQ10 group than the other two groups measured on cone beam computed tomography (CBCT). The relative gene expression of Runt-related transcription factor 2 (RUNX2) and Osteopontin (OPN) showed significant increase in the presence of CoQ10. Histomorphometry revealed significantly less fibrous tissue in the CoQ10 group in comparison to the control or collagen group. Conclusion: The local application of CoQ10 after tooth extraction provided a simple, inexpensive, yet effective treatment facilitating bone formation and healing in the extraction sockets of diabetic patients.

Alveolar ridge preservation reduces the need for ancillary bone augmentation in the context of implant therapy

Background

There is limited information on the need for bone augmentation in the context of delayed implant placement whether alveolar ridge preservation (ARP) is previously performed or not. The primary aim of this retrospective cohort study was to evaluate the efficacy of ARP therapy after tooth extraction compared with unassisted socket healing (USH) in reducing the need for ancillary bone augmentation before or at the time of implant placement.

Methods

Adult subjects that underwent non‐molar single tooth extraction with or without simultaneous ARP therapy were included in this study. Cone beam computed tomography scans obtained before tooth extraction and after a variable healing period were used to record the baseline facial bone thickness and to virtually plan implant placement according to a standard method. A logistic regression model was used to evaluate the effect of facial alveolar bone thickness upon tooth extraction and baseline therapy (USH or ARP) on the need for additional bone augmentation, adjusting for several covariates (i.e., age, sex, baseline KMW, and tooth type).

Results

One hundred and forty subjects that were equally distributed between both baseline therapy groups constituted the study population. Implant placement was deemed virtually feasible in all study sites. Simultaneous bone augmentation was considered necessary in 60% and 11.4% of the sites in the USH and ARP group, respectively. Most of these sites (64.2% in the USH group and 87.5% in the ARP group) exhibited a thin facial bone phenotype (<1 mm) at baseline. Logistic regression revealed that the odds of not needing ancillary bone augmentation were 17.8 times higher in sites that received ARP therapy. Furthermore, the need for additional bone augmentation was reduced 7.7 times for every 1 mm increase in facial bone thickness, regardless of baseline therapy.

Conclusions

Based on a digital analysis, ARP therapy, compared with USH, and thick facial alveolar bone largely reduce the need for ancillary bone augmentation at the time of implant placement in non‐molar sites.

The need for socket preservation: a systematic review

The aim of this study was to evaluate the clinical need and impact of socket preservation to protect the bone for future dental implant placement. Moreover, we aimed to list down various methods of socket preservation by going through randomized clinical trials. We searched PubMed, Google Scholar, and Cochrane databases for all relevant publications, where researchers compared various methods and tools for socket preservation. All eight randomized controlled trials mentioned several methods that are helpful in preserving bone levels both horizontally and vertically. The studies included in this systematic review demonstrate that each material has certain efficacy in preserving the socket after tooth extraction for future implant placement. Socket preservation methods and materials are effective in preparing patients for future prostheses.

Dimensional Changes in the Alveolus after a Combination of Immediate Postextraction Implant and Connective Grafting and/or Socket Shield Technique

Immediate implant placement protocols after dental extraction have enabled a reduction in surgical phases. This procedure has increased patient satisfaction and similar survival rates to late implant placement procedures. However, placing an implant immediately after dental extraction does not counteract the physiological remodeling of alveolar bone. For this reason, additional surgical techniques have been developed, such as the placement of a connective tissue graft (CTG) or the socket shield technique (SST). Dimensional changes in the peri-implant tissues were observed after placement of immediate implants following the extraction and CTG and/or SST. A total of 26 surgical interventions were carried out in which dimensional change variables of peri-implant tissues were analyzed. The preoperative state and immediate postoperative situation were compared with the situation after one year. Measurements were taken at 3, 5, and 7 mm from the gingival margin and analyzed in this CBCT radiological study (Planmeca Promax 3D). The implant platform was used as a reference point for the measurement of changes in alveolar crest height. One year after performing either of the two techniques (CTG and/or SST), a significant increase in the gingiva thickness and vestibular cortex occurred at 5 mm (0.65 ± 1.16 mm) and 7 mm (0.95 ± 1.45 mm) from the gingival margin. Additionally, an increase in thickness of palatal bone was registered at 3 mm (0.48 ± 0.90 mm). The graft placement group showed an increase in thickness of peri-implant tissue in the vestibular area after one year, although CTG and SST groups were clinically similar. The implementation of SST revealed promising results regarding the buccal thickness of hard and soft tissues after one year. A significant increase in vestibular cortical bone thickness, as well as the overall mucosa thickness and buccal bone at 3 mm from the gingival margin, was observed. A significant reduction in the distance from the bone crest to the platform was detected in both techniques. Both techniques (CTG and SST) are appropriate to provide sufficient volume to peri-implant tissues in the vestibular area of anterior maxillary implants. Some limitations were detected, such as the lack of an aesthetic analysis or small sample size, so results should be interpreted with caution. Future studies are necessary to further evaluate the long-term predictability of these techniques.

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

Objectives

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

Material and methods

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

Results

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

Conclusions

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

Classification Based on Extraction Socket Buccal Bone Morphology and Related Treatment Decision Tree

Background: Alveolar ridge preservation (ARP) can successfully reduce volumetric ridge changes. However, there is still no consensus on what technique is the most advantageous for each specific clinical scenario. Hence, the aim of the present paper was to provide a treatment decision tree to guide the choice of predictable ARP procedures based on extraction socket buccal bone morphology and integrity. Material and Methods: Three socket types (ST) are proposed and discussed based on buccal bone morphology (intact, dehiscence or fenestration). Results: A decision tree for ARP was developed in order to merge ST classification with suitable treatment modalities. In the decision tree, the issue of when to allow unassisted healing or ARP was discussed. Described methods included bone grafting and collagen plug, and absorbable membrane or non-resorbable membrane, with or without flap elevation. Conclusion: A decision tree for ARP procedures was provided to guide clinicians towards the most conservative and predictable treatment approach based on remaining socket anatomical structures after extraction.

Enamel matrix derivative (EMD) enhances the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs)

To investigate the EMD's capacity in BMSCs osteogenic differentiation. In vivo and in vitro, BMSCs were treated with EMD, scanning electron microscopy, and Alizarin Red staining were used to detect the changes in the osteogenic ability of BMSCs, and the proliferation ability of BMSCs was evaluated by CCK8. In addition, by adding xav939, a typical inhibitor of Wnt/β-catenin signaling pathway, the regulatory function of Wnt/β-catenin signaling was clarified. The results showed that EMD promote cell proliferation and 25 μg/ml EMD had the most significant effect. Cells inducing osteogenesis for 2 and 3 even 4 weeks, the cell staining is deeper in EMD treated group than that of the control (P < 0.05) by alizarin Red staining, suggesting more mineralization of BMSCs. In vivo implanting the titanium plate wrapped with 25 μg/ml EMD treated-BMSC film into nude mice for 8 weeks, more nodules were formed on the surface of the titanium plate than that the control (P < 0.05). HE showed that there is a little blue-violet immature bone-like tissue block. Besides, the expression of RUNX Family Transcription Factor 2 (Runx2), Osterix, Osteocalcin (OCN), collagen I (COLI), alkaline phosphatase (ALP) and β-catenin were inhibited in xav939 group (P < 0.05); Inversely, all were activated in EMD group (P < 0.05). In conclusion, EMD promoted the proliferation and osteogenic differentiation of BMSCs. EMD's function on BMSCs might be associated with the Wnt/β-catenin signaling pathway.

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

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of the 2020 professional literature in restorative dentistry to inform busy dentists regarding noteworthy scientific and clinical progress over the past year. Each member of the committee brings discipline-specific expertise to this work to cover this broad topic. Specific subject areas addressed include prosthodontics; periodontics, alveolar bone, and peri-implant tissues; implant dentistry; dental materials and therapeutics; occlusion and temporomandibular disorders (TMDs); sleep-related breathing disorders; oral medicine and oral and maxillofacial surgery; and dental caries and cariology. The authors focused their efforts on reporting information likely to influence day-to-day dental treatment decisions with a keen eye on future trends in the profession. With the tremendous volume of dentistry and related literature being published today, this review cannot possibly be comprehensive. The purpose is to update interested readers and provide important resource material for those interested in pursuing greater detail. It remains our intent to assist colleagues in navigating the extensive volume of important information being published annually. It is our hope that readers find this work useful in successfully managing the dental patients they encounter.

Alveolar ridge preservation: an overview of systematic reviews

The aim of this overview was to assess the methodological quality of systematic reviews of randomized clinical trials on alveolar ridge preservation after a tooth extraction. During March 2020, two independent reviewers performed an electronic search of the PubMed (MEDLINE), Scopus, Web of Science, and Cochrane Library databases to identify all relevant systematic reviews including randomized clinical trials on alveolar ridge preservation. A manual search of articles in renowned journals was also conducted. The methodological quality of the included reviews was determined using the AMSTAR-2 tool. From the 53 initially retrieved studies, 11 were finally included: three systematic reviews and eight systematic reviews with meta-analyses. The methodological quality of the included reviews was low or critically low. Higher quality clinical studies should be conducted prior to performing further reviews and these should meet the methodological requirements that are fundamental to this type of research.