Is alveolar ridge preservation an overtreatment?

Healing patterns of alveolar bone following ridge preservation procedures

OBJECTIVES

Examine the histomorphometric bone composition, following alveolar ridge preservation techniques and unassisted socket healing.

MATERIALS AND METHODS

Forty-two patients (42) requiring a single rooted tooth extraction were randomly allocated into three groups (n = 14 per group): Group 1: Guided Bone Regeneration (GBR) using deproteinised bovine bone mineral (DBBM) and a porcine collagen membrane; Group 2: Socket Seal (SS) technique using DBBM and a porcine collagen matrix; Group 3: Unassisted socket healing (Control). Trephined bone biopsies were harvested following a 4-month healing period. Forty-two samples underwent Back-Scattered Electrons -Scanning Electron Microscopy (BSE-SEM) imaging, with 15 samples examined using Xray Micro-Tomography (XMT) (n = 6 for each GBR/SS and n = 3 Control). Images were analysed to determine the percentage (%) of connective tissue, new bone formation, residual DBBM particles and direct bone to DBBM particle contact (osseointegration).

RESULTS

BSE-SEM analysis demonstrated that new bone formation was higher in the Control (45.89% ± 11.48) compared to both GBR (22.12% ± 12.7/p < .004) and SS (27.62% ± 17.76/p < .005) groups. The connective tissue percentage in GBR (49.72% ± 9), SS (47.81% ± 12.57) and Control (47.81% ± 12.57) groups was similar. GBR (28.17% ± 16.64) and SS (24.37% ± 18.61) groups had similar levels of residual DBBM particles. XMT volumetric analysis indicated a lower level of bone and DBBM particles in all test groups, when matched to the BSE-SEM area measurements. Osseointegration levels (DBBM graft and bone) were recorded at 35.66% (± 9.8) for GBR and 31.18% (± 19.38) for SS.

CONCLUSION

GBR and SS ARP techniques presented with less bone formation when compared to unassisted healing. GBR had more direct contact/osseointegration between the DBBM particles and newly formed bone.

Internal Allo-Cortical Tenting: A Modified Ridge Split Technique in Three-Dimensional Ridge Augmentation

Three-dimensional (3D) alveolar ridge deficiencies necessitate horizontal and vertical bone reconstruction for optimal implant positioning. Despite several available techniques, achieving desired augmentation outcomes remains challenging. This case study aims to present a modified ridge split technique for bone reconstruction in horizontal and vertical dimensions. The proposed technique was used to reconstruct the horizontal and vertical ridge defect from removing a previously failed implant. This technique includes placing a cortical allograft plate as an internal tent in the split ridge. A portion of the plate was inserted into the ridge, while the other part was placed in the coronal of the vertical defect. Additional guided bone regeneration was performed around the tented plate on both the buccal and lingual sides. After 5 months, cone beam computerized tomography revealed sufficient bone formation in horizontal and vertical dimensions. Within the limitations of the present case study, internal cortical tenting would be a reliable method for 3D bone reconstruction in cases where the ridge split is feasible.

Effect of alveolar ridge preservation at periodontally compromised molar extraction sockets: A retrospective cohort study

BACKGROUND

To date, the clinical evidence regarding the effectiveness of alveolar ridge preservation (ARP) in restricting alveolar bone height and width change after extraction at periodontally compromised molar extraction sockets still remains controversial. This retrospective cohort study aims to evaluate the effect of ARP in molars extracted for periodontal reasons.

METHODS

Retrospective data were collected from patient electronic records from January 2019 to December 2023. Patients with Stage III/IV periodontitis who underwent extraction of molars for periodontal reasons were screened for eligibility. The outcomes included the horizontal and vertical dimensions of alveolar bone. The need for additional augmentation procedure during implantation was also evaluated. A linear regression model was used to adjust for known confounders.

RESULTS

A total of 80 sockets were included in this study, of which 27 sockets received ARP therapy after extraction while 53 sockets experienced natural healing (NH). ARP resulted in significantly less bone height change in the periodontally compromised molar sites compared to the NH group (p < 0.001). In sockets displaying a height disparity of >2 mm between the buccal and palatal/lingual walls, the ARP group exhibited advantageous outcomes in terms of ridge width change, surpassing the NH group (p = 0.004). Moreover, the percentage for additional augmentation was significantly reduced in the ARP compared to the NH group (p = 0.006). Age, sex, smoking, jaw, location, and buccal wall thickness did not show any significant effect on bone height change.

CONCLUSION

ARP had benefits on limiting ridge resorption subsequent to molar extraction for periodontal reasons.

Healing of Extraction Sites after Alveolar Ridge Preservation Using Advanced Platelet-Rich Fibrin: A Retrospective Study

BACKGROUND

Over time, numerous surgical procedures and biomaterials have been proposed for the reconstruction of post-extraction bone defects, each with their advantages and disadvantages. The main objective of this study was to evaluate dimensional changes in the alveolar bone 3 months after tooth extraction, before implant planning, comparing alveolar ridge preservation (ARP) with spontaneous healing.

METHODS

A total of 84 patients with non-restorable molars were included in the study. Forty-two patients received ARP with advanced platelet-rich fibrin (A-PRF) and spontaneous healing was evaluated in these patients. Cone beam computed tomography (CBCT) analysis performed before and after surgical intervention was used to determine the changes in vertical and horizontal bone dimensions produced after tooth extraction.

RESULTS

CBCT measurements showed reduction in both vertical and horizontal alveolar bone size in both groups. For the study group, the alveolar parameters (height, width) were higher compared to the control group. The percentage variations between dimensional differences from the two groups were 38.58% for height, and for width were 36.88% at 0 mm, 35.56% at 3 mm, 36.61% at 5 mm, and 38.73% at 7 mm. The differences were statistically significant (p ˂ 0.0005).

CONCLUSIONS

The results obtained after ARP with A-PRF showed a reduced loss of bone volume compared to spontaneous healing.

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.

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.

Effectiveness of a collagen matrix seal and xenograft in alveolar ridge preservation: an experimental study in dogs

Majority of previous studies on alveolar ridge preservation (ARP) used collagen membranes as barrier membranes, and further evidence for ARP in dehiscent extraction sockets with a deproteinized bovine bone mineral (DBBM) and matrix is needed. The aim of this study is to assess the impact of non-cross linked collagen membranes (membrane) and crosslinked collagen matrices (matrix) on ARP using DBBM in extraction sockets with buccal dehiscence. In six mongrel dogs, the mesial roots of three mandibular premolars (P2, P3, and P4) were extracted 1 month after dehiscence defect induction. Two experimental groups were randomly assigned: (1) DBBM with a membrane (DBBM/membrane group) and (2) DBBM with a matrix (DBBM/matrix group). Three-dimensional (3D) volumetric, microcomputed tomography (μCT), and histologic analyses were performed to assess the ridge preservation. Both groups were effective to maintain the ridge width (p > 0.05), and the DBBM/matrix group showed more favorable soft tissue regeneration and bone quality in the histological analysis (p = 0.05). Based on these results, DBBM/matrix could be better choice for ARP in cases of buccal dehiscence defects.

Perigraftitis and implant therapy: A case report

BACKGROUND

A previous case study reported periimplantitis and concomitant perigraftitis of a second implant placed at a site that had alveolar ridge preservation three decades earlier. Infection at the site persisted 4 months after implant removal by flapless implant reversal. A flap was subsequently reflected, the grafted bone was removed, and a second alveolar ridge preservation was performed with a freeze-dried bone allograft. The publication reported infection resolved, and the site healed uneventfully. However, it is unknown if placement of another implant at the site would be successful. The purpose of this paper is to report on the findings at surgical reentry and outcome of the third implant.

METHODS

Eleven months after the second alveolar ridge preservation, the site was reentered. The bone graft was found to be partially soft tissue encapsulated. All encapsulated graft materials and soft tissue were removed. An implant was placed, and the alveolar defect was grafted with a demineralized bone allograft. Seventeen months after implant placement, a buccal free gingival graft was performed during which the crestal bone adjacent to the implant was found to be hard and corticated. The implant was deemed to be osseointegrated and restored after soft tissue healing.

RESULTS

Twenty-five months after implant placement, the third implant remained functional and asymptomatic with the peri-implant bone exhibiting normal trabeculation.

CONCLUSIONS

Implant therapy can be successful following treatment and resolution of perigraftitis.

KEY POINTS

Perigraftitis may play a contributing role in the biologic complications of implants that have been placed into grafted bone. Perigraftitis may be successfully resolved by completely removing all grafted bone. Once perigraftitis has been eliminated, an implant may be successfully placed.

Socket Preservation and Guided Bone Regeneration: Prerequisites for Successful Implant Dentistry

Implant success is measured not only by implant survival but also by the long-term aesthetic and functional results. Implant placement should be prosthetically driven, with proper three-dimensional positioning for optimal support and stability of the tissues. Several procedures could be performed to ensure this requirement. While socket preservation (SP) is performed at the stage of tooth extraction, guided bone regeneration (GBR) takes place before or simultaneous to implant placement. The current review aims to summarize and discuss the procedures used for the preparation of the implant site, the preservation of the existing tissues, and their augmentation in cases of deficiency. An electronic search using Google Scholar, PubMed, and Scopus was conducted up to October 2023, in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The review summarizes the current knowledge on SP and GBR as prerequisites for future implant placement. Their indications, advantages, and limitations have been thoroughly evaluated and some recommendations for further research have been suggested. Implant placement in sites with severe bone resorption is extremely challenging. It necessitates the application of different surgical techniques, especially augmentation procedures, including guided bone regeneration. The need for such procedures could be avoided or at least minimized by the execution of SP after tooth extraction or immediate/early implant placement.