Autologous Tooth Graft after Endodontical Treated Used for Socket Preservation: A Multicenter Clinical Study

The Influence of Different Preservation Protocols on the Teeth's Osteoinductive Characteristics: An In Vitro Study

The purpose of this study was to evaluate in vitro whether the type of tooth preservation before treatment with the Tooth Transformer® (TT) device affects the osteoinductive characteristics of the extracted tooth. Forty extracted teeth from healthy non-smoking patients were selected. All teeth were cleaned of caries, tartar, and filling material and then roughly sectioned and divided into four experimental groups according to storage type: room-temperature (RT) tooth samples, frozen tooth samples, RIPA tooth samples, and fresh tooth samples. Each sample was minced, demineralized, and disinfected using the TT device. The Enzyme-Linked ImmunoSorbent Assay (ELISA) test revealed the presence of bone morphogenetic protein-2 (BMP-2) and collagen type-I (COL-I) in all of the samples, demonstrating that the fresh teeth retained the most significant amount of osteoinductive protein. In contrast, the tooth samples stored at room temperature (RT) showed the most important loss of BMP-2 and COL-I. A Western Blot analysis demonstrated the presence of the Mineralization Protein LIM-1 (LMP-1) and Transforming Growth Factor-β (TGF-β) in all of the dental samples analyzed. The fresh and frozen dental samples showed significantly higher levels of LMP-1 than those in the other samples. In contrast, the levels of TGF-β were similar in all of the dental samples examined, regardless of the type of storage. These experimental results suggest that an extracted tooth should be treated with the TT device as soon as possible to maximize its osteoinductive potential in surgical bone preservation and regeneration procedures.

Alveolar ridge preservation with autogenous tooth graft: A histomorphometric analysis of 36 consecutive procedures

BACKGROUND

The aim of this study was to analyze the histomorphometric findings of autogenous tooth grafting (ATG) for alveolar ridge preservation (ARP), using graft material from extracted teeth. Variations by sex, age and location of extracted teeth, as well as any associated complications, were also assessed.

MATERIALS AND METHODS

This prospective, single-cohort study was conducted using ATG placed in extraction sockets. After 5 months healing, bone biopsies were collected during implant placement and analyzed histomorphometrically to assess new vital bone, residual biomaterial, and connective tissue. The results underwent statistical analysis; non-parametric tests (Mann Whitney test for independent samples and the Kruskal-Wallis test) were applied.

RESULTS

27 patients (16 females, 11 males) underwent 36 ARP procedures. Histomorphometric analysis revealed a mean percentage of new vital bone of 29.14 % ( ± 10.86), residual tooth graft of 10.84 % ( ± 6.82), and intertrabecular connective tissue of 59.87 % ( ± 10.56). No significant differences were found in relation to age, sex or location.

CONCLUSIONS

ATG appears to be a promising material for ARP, without significant complications. Further comparative studies are needed to better understand this material's behavior.

Regeneration of Critical Calvarial Bone Defects Using Bovine Xenograft, Magnesium-Enriched Bovine Xenograft and Autologous Dentin in Rats: Micro-CT, Gene Expression and Immunohistochemical Analysis

The aim of this study was to evaluate the efficacy of autologous dentin (AD), bovine xenograft (BX) and magnesium-enriched bovine xenograft (BX + Mg) in the healing of critical cranial bone defects (CCBDs) in rats. Eighty male Wistar rats were divided into four groups: BX, BX + Mg, AD and the control group (no intervention). Eight mm CCBDs were created and treated with the respective biomaterials. Healing was assessed 7, 15, 21 and 30 days after surgery by micro-computed tomography (micro-CT), real-time polymerase chain reaction (RT-PCR) and immunohistochemical analysis. Micro-CT analysis showed that AD had the highest bone volume and the least amount of residual biomaterial at day 30, indicating robust bone formation and efficient resorption. BX + Mg showed significant bone volume but had more residual biomaterial compared to AD. RT-PCR showed that the expression of osteocalcin (OC), the receptor activator of nuclear factor κB (RANK) and sclerostin (SOST), was highest in the AD group at day 21 and vascular endothelial growth factor (VEGF) at day 15, indicating increased osteogenesis and angiogenesis in the AD group. Immunohistochemical staining confirmed intense BMP-2/4 and SMAD-1/5/8 expression in the AD group, indicating osteoinductive properties. The favorable gene expression profile and biocompatibility of AD and BX + Mg make them promising candidates for clinical applications in bone tissue engineering. Further research is required to fully exploit their potential in regenerative surgery.

Tooth Graft: An Umbrella Overview

This umbrella review aims to evaluate systematic/meta-analysis studies containing clinical evidence on tooth grafts as bone substitutes in the oral and maxillofacial regions. Using language restrictions and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, an electronic database search of PubMed, MEDLINE, Embase, Cochrane library, and Google Scholar was conducted, featuring published studies up until August 2022. All systematic/meta-analysis review articles relating to tooth graft materials were matched against the inclusion criteria. Two qualified researchers independently assessed the studies' inclusion or exclusion criteria and risk of bias, and a third investigator assisted in resolving ambiguities. A total of 81 systematic/meta-analysis studies, comprising 21 animal-controlled trials, 23 randomized controlled human trials, 23 prospective studies, and 14 retrospective studies, were selected for this study. A small risk of bias was observed in systematic studies/meta-analyses. In addition, the clinical evidence from the analysis of these studies revealed a low incidence of side effects. According to the current review, two systematic reviews indicated that autogenous bone grafting of prepared teeth might be as effective as other bone grafting materials. Four studies also mentioned autologous grafts as potential alternatives to autologous grafts, autogenous demineralized dentin (ADDM), engineered grafts, root blocks, and dental matrix. On the other hand, three systematic studies stated that more long-term research is needed to confirm their findings. Finally, given the importance of standardization and homogeneity of studies for clinical cases, it is advised to be used cautiously due to the risks of transplant rejection.

Socket Preservation Using Dentin Mixed with Xenograft Materials: A Pilot Study

BACKGROUND

The use of human dentin matrix could serve as an alternative to autologous, allogenic, and xenogeneic bone grafts due to its osteoinductive characteristics. The limitations of its use is tooth availability and that it is often necessary to mix it with a biomaterial.

AIM

The aim of this study was to analyze a mix of two different graft materials with different reabsorption ranges when the dentin graft material was not sufficient for full socket preservation.

METHODS

Seven socket preservation surgeries were carried out employing a mixed graft material containing 50% dentin and 50% xenograft. After four months of recovery, the implants were positioned. At the time of the prosthesis placement and implant surgery, bone samples were collected.

RESULTS

The histologic analysis revealed no inflammatory or infective reaction against the seven biopsies. The histomorphometric graft analysis revealed an amount of New Bone of 29.03 ± 6.57% after 4 months and 34.11 ± 5.02% after 8 months.

CONCLUSIONS

The two graft materials had a different volume reabsorption rate: 71% after 4 months and 90% after 8 months for dentin, and 6% after 4 months and 26% after 8 months for the xenograft. The space created by the dentin reabsorption increased the quantity of new bone.

Dentin, Dentin Graft, and Bone Graft: Microscopic and Spectroscopic Analysis

BACKGROUND

The use of the human dentin matrix could serve as an alternative to autologous, allogenic, and xenogeneic bone grafts. Since 1967, when the osteoinductive characteristics of autogenous demineralized dentin matrix were revealed, autologous tooth grafts have been advocated. The tooth is very similar to the bone and contains many growth factors. The purpose of the present study is to evaluate the similarities and differences between the three samples (dentin, demineralized dentin, and alveolar cortical bone) with the aim of demonstrating that the demineralized dentin can be considered in regenerative surgery as an alternative to the autologous bone.

METHODS

This in vitro study analyzed the biochemical characterizations of 11 dentin granules (Group A), 11 demineralized using the Tooth Transformer (Group B), and dentin granules and 11 cortical bone granules (Group C) using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) to evaluate mineral content. Atomic percentages of C (carbon), O (oxygen), Ca (calcium), and P (phosphorus) were individually analyzed and compared by the statistical t-test.

RESULTS

The significant p-value (p < 0.05) between group A and group C indicated that these two groups were not significantly similar, while the non-significant result (p > 0.05) obtained between group B and group C indicated that these two groups are similar.

CONCLUSIONS

The findings support that the hypothesis that the demineralization process can lead to the dentin being remarkably similar to the natural bone in terms of their surface chemical composition. The demineralized dentin can therefore be considered an alternative to the autologous bone in regenerative surgery.

The use of autogenous tooth bone graft is an efficient method of alveolar ridge preservation - meta-analysis and systematic review

BACKGROUND

Ridge resorption following tooth extraction may be reduced by alveolar ridge preservation (ARP). Previous randomized clinical trials and systematic reviews have suggested that autogenous tooth bone graft (ATB) can be an effective alternative material for ARP. However, the results are heterogeneous. Therefore, our research aimed to evaluate the efficacy of ATB in ARP.

METHODS

A systematic search was conducted in Cochrane Library, Embase, MEDLINE and Scopus for studies published from inception to 31 November 2021. We searched searched for randomized, non-randomized controlled trials and case series reporting on ATB use for ARP. The primary outcome was the ridge width difference pre- and post-surgery, measured in millimetres (mm) measured on CBCT (cone beam computed tomography). The secondary outcomes were the histological results. We followed the PRISMA2020 recommendations for reporting our systematic review and meta-analysis.

RESULTS

The analysis included eight studies for the primary and six for the secondary outcomes. The meta-analysis revealed a positive ridge preservation effect with a pooled mean difference ridge width change of -0.72 mm. The pooled mean residual graft proportion was 11.61%, and the newly formed bone proportion was 40.23%. The pooled mean of newly formed bone proportion was higher in the group where ATB originated from both the root and crown of the tooth.

CONCLUSIONS

ATB is an effective particulate graft material in ARP. Complete demineralization of the ATB tends to decrease the proportion of newly formed bone. ATB can be an attractive option for ARP.

TRIAL REGISTRATION

The study protocol was registered on PROSPERO (CRD42021287890).

Autologous Tooth Graft: Innovative Biomaterial for Bone Regeneration. Tooth Transformer® and the Role of Microbiota in Regenerative Dentistry. A Systematic Review

Different biomaterials, from synthetic products to autologous or heterologous grafts, have been suggested for the preservation and regeneration of bone. The aim of this study is to evaluate the effectiveness of autologous tooth as a grafting material and examine the properties of this material and its interactions with bone metabolism. PubMed, Scopus, Cochrane Library, and Web of Science were searched to find articles addressing our topic published from 1 January 2012 up to 22 November 2022, and a total of 1516 studies were identified. Eighteen papers in all were considered in this review for qualitative analysis. Demineralized dentin can be used as a graft material, since it shows high cell compatibility and promotes rapid bone regeneration by striking an ideal balance between bone resorption and production; it also has several benefits, such as quick recovery times, high-quality newly formed bone, low costs, no risk of disease transmission, the ability to be performed as an outpatient procedure, and no donor-related postoperative complications. Demineralization is a crucial step in the tooth treatment process, which includes cleaning, grinding, and demineralization. Since the presence of hydroxyapatite crystals prevents the release of growth factors, demineralization is essential for effective regenerative surgery. Even though the relationship between the bone system and dysbiosis has not yet been fully explored, this study highlights an association between bone and gut microbes. The creation of additional scientific studies to build upon and enhance the findings of this study should be a future objective of scientific research.

Autogenous particulated dentin for alveolar ridge preservation. A systematic review

PURPOSE

This review aimed to investigate the clinical outcomes of autogenous particulated dentin (APD) used for alveolar ridge preservation (ARP), evaluating volume gain, histologic/histomorphometric data, and associated complications.

MATERIAL AND METHODS

The review followed PRISMA guidelines and was registered in the International Prospective Register of Systematic Reviews (PROSPERO). An automated search was made in four databases (Medline/Pubmed, Scopus, Web of Science, and Cochrane Library) supplemented by a manual search for relevant clinical articles published before March 10th, 2022. The review included human studies of at least four patients in which extraction and subsequent ARP were performed in a single surgery. Both comparative studies and studies that assessed ARP with APD exclusively were admitted. The quality of evidence was assessed with the Cochrane bias assessment tool, the Newcastle-Ottawa Quality Assessment Scale, and the Joanna Briggs Institute Critical Appraisal tool.

RESULTS

Eleven studies fulfilled the inclusion criteria and were included for descriptive analysis, with a total of 215 patients, and 337 alveoli preserved by APD, spontaneous healing (blood clot), or other bone substitutes, obtaining comparatively less vertical and horizontal resorption when APD was used.

CONCLUSIONS

After dental extraction, autogenous dentin was effective in terms of volume maintenance, showing promising results in histologic/histomorphometric analysis, and a low complication rate. Nevertheless, few comparative studies with comparable parameters have been published and so more research providing long-term data is needed to confirm these findings.

Autogenous Dentin Particulate Graft for Alveolar Ridge Augmentation with and without Use of Collagen Membrane: Preliminary Histological Analysis on Humans

(1) Background: The phenomenon of ankylosis of the dental elements has led clinicians to think that properly treated dentin and cement may be a potential graft for alveolar ridge augmentation. Currently, there are no studies in the literature able to histomorphometrically compare the healing patterns of an autogenous dentin particulate graft with the association, or not, of resorbable membranes. The aim of this pilot study is to histologically compare bone after an alveolar ridge augmentation using an autogenous dentin particulate graft with and without a resorbable collagen membrane. (2) Methods: this clinical trial enrolled six patients with defects requiring bone augmentation. Two procedures were performed in all six adult human patients in order to perform a study-control study: in Group 1, a ridge augmentation procedure with an autogenous dentin particulate graft and a resorbable collagen membrane was performed, and, in Group 2, an alveolar ridge preservation without a membrane was performed at the same time (T0). At 4 months, a biopsy of the bone tissues was performed using a 4 mm trephine bur in order to perform a histomorphometric analysis. (3) Results: The histomorphometric analysis demonstrated that Group 1 presented 45% of bone volume, 38% of vital bone, and 7% of residual graft. On the contrary, membrane-free regenerative procedures demonstrated 37% of bone volume, 9% of vital bone, and 27% of non-resorbed graft. In all cases, the regenerated bone allowed the insertion of implants with a standard platform, and no early failures were recorded. (4) Conclusions: Autogenous dentin particulate grafts seem to work best when paired with a membrane.

Autogenous tooth bone graft material prepared chairside and its clinical applications: a systematic review

This systematic review was conducted to evaluate the available literature on the clinical outcomes of the use of autogenous tooth bone graft prepared chairside, and its current applications. A literature search was done to answer the focused questions "In partially edentulous patients, what are the alveolar ridge volumetric changes, histological findings, and implant survival rates in sites augmented with autogenous tooth bone graft prepared chairside?" Twenty articles were included at the end of the database search. Reported alveolar bone dimension changes after ridge preservation ranged between - 0.64 mm and + 2.26 mm for height, and between - 1.21 mm and + 0.41 mm for width. Augmented sites showed a significant increase in their dimensions in all investigations. The implant survival rate was 98.8% for delayed placement and 97.4% for immediate placement. Additional reports were found on the percentage bone formation following the use of this graft at different postoperative time points, which showed a higher bone volume with time. Currently available studies have included small samples, with short follow-up periods, and most have lacked a control group. Within the limitations of this review, the available evidence suggests that the autogenous tooth bone graft prepared chairside is as effective as other bone grafting materials.

Innovative Concepts and Recent Breakthrough for Engineered Graft and Constructs for Bone Regeneration: A Literature Systematic Review

BACKGROUND

For decades, regenerative medicine and dentistry have been improved with new therapies and innovative clinical protocols. The aim of the present investigation was to evaluate through a critical review the recent innovations in the field of bone regeneration with a focus on the healing potentials and clinical protocols of bone substitutes combined with engineered constructs, growth factors and photobiomodulation applications.

METHODS

A Boolean systematic search was conducted by PubMed/Medline, PubMed/Central, Web of Science and Google scholar databases according to the PRISMA guidelines.

RESULTS

After the initial screening, a total of 304 papers were considered eligible for the qualitative synthesis. The articles included were categorized according to the main topics: alloplastic bone substitutes, autologous teeth derived substitutes, xenografts, platelet-derived concentrates, laser therapy, microbiota and bone metabolism and mesenchymal cells construct.

CONCLUSIONS

The effectiveness of the present investigation showed that the use of biocompatible and bio-resorbable bone substitutes are related to the high-predictability of the bone regeneration protocols, while the oral microbiota and systemic health of the patient produce a clinical advantage for the long-term success of the regeneration procedures and implant-supported restorations. The use of growth factors is able to reduce the co-morbidity of the regenerative procedure ameliorating the post-operative healing phase. The LLLT is an adjuvant protocol to improve the soft and hard tissues response for bone regeneration treatment protocols.

Implants Survival Rate in Regenerated Sites with Innovative Graft Biomaterials: 1 Year Follow-Up

In thirteen different dental clinics in Singapore, Spain, Czech Republic and Italy, 504 patients were selected, and 483 dental implants were placed in maxillary sites after alveolar socket preservation (ASP) procedures with an autologous demineralized tooth extracted as graft material from an innovative Tooth Transformer device was obtained. All procedures used were reported in n°638 Ethical Committee surgical protocol of University of Chieti and approved. After 4 months, at dental implant placing, bone biopsies were performed to evaluate the histologic outcomes, and 12 months after implant loading, global implant survival rate, failure percentage and peri-implant bone loss were detected. After ASP, only 27 post-operative complications were observed and after 4 months, bone biopsy histomorphometric analysis showed a high percentage of bone volume (BV) 43.58 (±12.09), and vital new bone (NB) 32.38 (±17.15) with an absence of inflammation or necrosis areas. Twelve months after loading, only 10 dental implants failed (2.3%), with a 98.2% overall implant survival rate, nine cases showed mucositis (1.8%) and eight showed peri-implantitis (1.6%). At mesial sites, 0.43 mm (±0.83) of bone loss around the implants was detected and 0.23 mm (±0.38) at the distal sites with an average value of 0.37 mm (±0.68) (p > 0.568). Several studies with a longer follow-up will be necessary to confirm the preliminary data observed. However, clinical results seem to suggest that the post-extraction socket preservation procedure using innovative demineralized autologous tooth-derived biomaterial may be a predictable procedure to produce new vital bone able to support dental implant rehabilitation of maxilla edentulous sites.

Multifrequency Impedance Method Based on Neural Network for Root Canal Length Measurement

Root canal therapy is the most fundamental and effective approach for treating endodontics and periapicalitis. The length of the root canal must be accurately measured to clean the pathogenic substances in it. This study aims to present a multifrequency impedance method based on a neural network for root canal length measurement. A circuit system was designed which generates a current of frequencies from 100 Hz to 20 kHz in order to augment the data of impedance ratios with different combinations of frequencies. Several impedance ratios and other quantified characteristics, such as the type of tooth and file, were selected as features to train a neural network model that could predict the distance between the file and apical foramen. The model uses leave-one-out cross-validation, adopts the Adam optimizer and regularization, and has two hidden layers with nine and five nodes, respectively. The neural network-based multifrequency impedance method exhibits nearly 95% accuracy, compared with the dual-frequency impedance ratio method (which demonstrated no more than 85% accuracy in some situations). This method may eliminate the influence of human and environmental factors on measurement of the root canal length, thereby increasing measurement robustness.

Autologous Deciduous Tooth-Derived Material for Alveolar Ridge Preservation: A Clinical and Histological Case Report

The management of the alveolar socket is fundamental to create conditions that would allow the positioning of dental implants in the same site, when required. A number of biomaterials were described in scientific literature to be used for alveolar socket preservation immediately after tooth extraction: autogenous grafts, allograft (of various origin), and synthetic products. Among the autogenous biomaterials, some authors proposed the use of autogenous dentin and/or enamel, retrieved from teeth, adequately managed, and purified. The present case report with two-year follow-up shows one case of alveolar socket preservation by using tooth graft material that was subsequently treated with one implant-supported rehabilitation in the same site. The paper presents clinical and histological outcomes and confirms the feasibility of adopting such autogenous biomaterial in standard procedures.

Alveolar Socket Preservation with Different Autologous Graft Materials: Preliminary Results of a Multicenter Pilot Study in Human

BACKGROUND

The histological and histomorphometrical results were evaluated between vital whole and non-vital endodontically treated teeth used as autologous grafts in post-extractive socket preservation procedures.

METHODS

Twenty-eight patients (average age 51.79 ± 5.97 years) with post-extractive defects were enrolled in five dentistry centers. All patients were divided into two groups: with whole teeth (Group 1) and teeth with endodontical root canal therapy (Group 2). The extracted teeth were processed with the Tooth Transformer device to obtain a demineralized and granulated graft material used with a resorbable collagen membrane for socket preservation. After four months, 32 bone biopsies were obtained for histological, histomorphometric, and statistical analysis.

RESULTS

During the bone healing period, no infection signs were observed. Nineteen biopsies in group 1 and 13 biopsies in group 2 were detected. The histological analysis showed neither inflammatory nor infective reaction in both groups. Autologous grafts surrounded by new bone were observed in all samples and, at high magnification, partially resorbed dentin and enamel structures were detected. No gutta-percha or cement was identified. Small non-statistically significant differences between the groups, in total bone volume (BV), autologous graft residual, and vital bone percentage were detected.

CONCLUSIONS

The study showed that the TT Transformer grafts were capable of producing new vital bone in socket preservation procedures. The histomorphometric results showed no statistical differences comparing whole and endodontically treated teeth in bone regeneration. Further studies will be carried out in order to understand the advantages of the autologous graft materials obtained from the tooth compared with the current biomaterials in bone regeneration treatments.