Alveolar Bone Remodeling with or without Collagen Filling of the Extraction Socket: A High-Resolution X-ray Tomography Animal Study

Sclerostin antibody enhances implant osseointegration in bone with Col1a1 mutation

We evaluated the potential of sclerostin antibody (SclAb) therapy to enhance osseointegration of dental and orthopaedic implants in a mouse model (Brtl/+) mimicking moderate to severe Osteogenesis Imperfecta (OI). To address the challenges in achieving stable implant integration in compromised bone conditions, our aim was to determine the effectiveness of sclerostin antibody (SclAb) at improving bone-to-implant contact and implant fixation strength. Utilizing a combination of micro-computed tomography, mechanical push-in testing, immunohistochemistry, and Western blot analysis, we observed that SclAb treatment significantly enhances bone volume fraction (BV/TV) and bone-implant contact (BIC) in Brtl/+ mice, suggesting a normalization of bone structure toward WT levels. Despite variations in implant survival rates between the maxilla and tibia, SclAb treatment consistently improved implant stability and resistance to mechanical forces, highlighting its potential to overcome the inherent challenges of OI in dental and orthopaedic implant integration. These results suggest that SclAb could be a valuable therapeutic approach for enhancing implant success in compromised bone conditions.

Survival analysis of dental implants placed in horizontally severely resorbed maxillae after reconstruction with xenogeneic graft: a case series

PURPOSE

To evaluate the survival rates of dental implants with a hybrid macrostructure and the surface biomimetically coated with nanohydroxyapatite, placed in horizontally atrophic maxillae previously submitted to the guided bone regeneration (GBR) procedure, associated with the use of a deproteinized bovine bone graft (DBB).

METHODS

Twenty-five patients who received 196 implants were involved in this study. First, these patients were submitted to GBR procedures and maxillary sinus lift, where DBB was used as the grafting material. The dental implants were placed after a minimum period of 6 months of the grafting procedures. The patients were followed up every six months and clinical/radiographic examinations were performed to assess the implants, using the following indicators as a reference: (1) Absence of mobility; (2) Absence of pain. Data about the age, surgery time, smoking status, implant size, and time between the grafting procedure and implant placement were correlated with implant failures.

RESULTS

Twelve implants failed, generating a survival rate of 94.23%. None of the variables analysed correlated with the implant failures.

CONCLUSION

Implants with a hybrid macrostructure and surface biomimetically coated with nanohydroxyapatite present good survival rates in horizontally atrophic maxillae grafted with DBB.

Anatomical Factors of the Anterior and Posterior Maxilla Affecting Immediate Implant Placement Based on Cone Beam Computed Tomography Analysis: A Narrative Review

BACKGROUND

The aim of this narrative review was to provide insights into the influence of the morphological characteristics of the anatomical structures of the upper jaw based on cone beam computed tomography (CBCT) analysis on the immediate implant placement in this region.

MATERIAL AND METHODS

To conduct this research, we used many electronic databases, and the resulting papers were chosen and analyzed. From the clinical point of view, the region of the anterior maxilla is specific and can be difficult for immediate implant placement.

FINDINGS

Anatomical structures in the anterior maxilla, such as the nasopalatine canal and accessory canals, may limit and influence the implant therapy outcome. In addition to the aforementioned region, immediate implant placement in the posterior maxilla may be challenging for clinicians, especially in prosthetic-driven immediate implant placement procedures. Data presented within the recently published materials summarize the investigations performed in order to achieve more reliable indicators that may make more accurate decisions for clinicians.

CONCLUSION

The possibility for immediate implant placement may be affected by the NPC shape in the anterior maxilla, while the presence of ACs may increase the incidence of immediate implant placement complications. The variations in IRS characteristics may be considered important criteria for choosing the implant properties required for successful immediate implant placement.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Thermal implant removal in a pig jaw: a proof of concept study

OBJECTIVES

The aim of this study was to evaluate whether thermal implant removal of osseointegrated implants is possible using a diode laser with an specific temperature-time interval.

MATERIALS AND METHODS

First, tooth extraction of the first three premolars was performed in the maxilla and mandible on both sides of 10 pig. After 3 months, implants were inserted into the upper and lower jaws of 10 pigs. After 3 more months, osseointegrated implants were heated with a laser device to a temperature of 50 °C for 1 min. After 14 days, the implant stability quotient (ISQ), torque-out values, and bone-to-implant contact (BIC) ratio were assessed using resonance frequency analysis.

RESULTS

ISQ values showed no significant differences within each group or between the control and test groups. Furthermore, torque-out and BIC value measurements presented no significant differences between the groups.

CONCLUSIONS

At 50°C, changes in the BIC values were noticeably smaller; however, these differences were not significant. Future studies should evaluate the same procedures at either a higher temperature or longer intervals.

CLINICAL RELEVANCE

With only 50 °C for 1 min, a dental implant will not de-integrate predictably.

Tomographic assessment of bone changes in atrophic maxilla treated by split-crest technique and dental implants with platelet-rich fibrin and NanoBone® versus platelet-rich fibrin alone: Randomized controlled trial

BACKGROUND

This study evaluated the clinical benefits of adding NanoBone® with split-crest technique and simultaneous implant placement covered with platelet-rich fibrin membrane in horizontally deficient maxillary ridges in terms of crestal and horizontal bone changes and patient morbidity.

METHODS

Forty patients indicated for maxillary ridge splitting and simultaneous implant placement were assigned randomly to the study groups: control group (Platelet Rich Fibrin membrane) and test group (Platelet Rich Fibrin membrane + Nanobone®). The Cone Beam Computed Tomography Fusion technique was utilized to assess crestal and horizontal bone changes after five months of the surgical procedure. Patient morbidity was recorded for one week post-surgical.

RESULTS

Five months post-surgical, buccal crestal bone resorption was 1.26 ± 0.58 mm for the control group and 1.14 ± 0.63 mm for the test group. Lingual crestal bone resorption was 1.40 ± 0.66 mm for the control group and 1.47 ± 0.68 mm for the test group. Horizontal bone width gain was 1.46 ± 0.44 mm for the control group and 1.29 ± 0.73 mm for the test group. There was no significant statistical difference between study groups regarding crestal and horizontal bone changes and patient morbidity.

CONCLUSIONS

The tomographic assessment of NanoBone® addition in this study resulted in no statistically significant difference between study groups regarding crestal and horizontal bone changes and patient morbidity. More randomized controlled clinical trials on gap fill comparing different bone grafting materials versus no grafting should be conducted.

CLINICALTRIALS

GOV REGISTRATION NUMBER

NCT02836678, 13th January 2017.

Current Knowledge on the Healing of the Extraction Socket: A Narrative Review

The concept of extraction socket healing has been severally researched and reported over the years, since tooth extraction remains one of the most common procedures performed in the dental clinic. Understanding this healing process is of utmost importance because the outcome has a direct bearing on future prosthetic rehabilitation and, by extension, on patients' esthetics and masticatory function, among others. This mini review, therefore, summarized the current knowledge on the different stages of socket healing, including the biologic and clinical events that occur following tooth extraction up until the complete closure of the socket. Additionally, the modeling of the alveolar bone/process post extraction, and the resultant dimensional changes that, altogether, shape the bone, were reviewed and documented. The effects of various socket preservation interventions to mitigate these dimensional changes, and therefore preserve the alveolar process in a condition suitable for future prosthetic rehabilitation, were highlighted. Finally, a review of some of the factors that influence the entire process was also carried out.

Evaluation of a Granular Bone Substitute for Bone Regeneration Using an Optimized In Vivo Alveolar Cleft Model

Alveolar cleft is a common congenital deformity that requires surgical intervention, notably using autologous bone grafts in young children. Bone substitutes, in combination with mesenchymal stem cells (MSCs), have shown promise in the repair of these defects. This study aimed to evaluate the regenerative capabilities of a granular bone substitute using an optimized alveolar cleft model. Thirty-six rats underwent a surgical procedure for the creation of a defect filled with a fragment of silicone. After 5 weeks, the silicone was removed and the biomaterial, with or without Wharton's jelly MSCs, was put into the defect, except for the control group. The rats underwent μCT scans immediately and after 4 and 8 weeks. Analyses showed a statistically significant improvement in bone regeneration in the two treatment groups compared with control at weeks 4 and 8, both for bone volume (94.64% ± 10.71% and 91.33% ± 13.30%, vs. 76.09% ± 7.99%) and mineral density (96.13% ± 24.19% and 93.01% ± 27.04%, vs. 51.64% ± 16.51%), but without having fully healed. This study validates our optimized alveolar cleft model in rats, but further work is needed to allow for the use of this granular bone substitute in the treatment of bone defects.

Socket Preservation after Tooth Extraction: Particulate Autologous Bone vs. Deproteinized Bovine Bone

Background: The technique of socket preservation after tooth extraction allows for less volumetric decrease after tooth extraction. The aim of this retrospective study was to evaluate differences between alveolar socket preservation performed with deproteinized bovine bone graft and autologous particulate bone graft taken from the mandibular ramus. Materials and Methods: This retrospective study enrolled a total of 21 consecutive patients. A total of 11 patients underwent socket preservation with deproteinized bovine bone graft and collagen matrix (group A), and 10 patients underwent socket preservation performed with particulate autologous bone taken from the mandibular ramus and collagen matrix (group B). All patients received cone beam computed tomography (CBCT) before socket preservation and after four months. Alveolar bone width (ABW) values and alveolar bone height (ABH) values were measured at the first and second CBCT, and the reduction of the values in the two groups was compared. Statistical analysis was performed using Student’s t-test for independent variables, and p values < 0.05 were considered statistically significant. Results: There were no statistically significant differences between ABW reduction of group A and ABW reduction of group B (t-test value p = 0.28). There were no statistically significant differences between ABH reduction of group A and ABH reduction of group B (t-test value p = 0.10). Conclusions: In this retrospective study, no statistical differences were found between the group that received autologous particulate bone compared to the group that received deproteinized bovine bone in socket preservation.

[Models of bone defects in rabbits used to evaluate the bone graft materials efficacy]

The review deals with the main types of experimental models of bone defects of the skull in rabbits. The information about the types of critical defects, methods of their modeling and the possibilities of application of the described models in the studies of bone graft materials in dentistry and maxillofacial surgery is systematized.