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Journal of Oral Biology and... 2024Application of alveolar bone graft (ABG) in alveolar augmentation is done to prevent excessive bone resorption due to tooth extraction, missing teeth, or other... (Review)
Review
INTRODUCTION
Application of alveolar bone graft (ABG) in alveolar augmentation is done to prevent excessive bone resorption due to tooth extraction, missing teeth, or other diseases/conditions affecting the alveolar bone. The use of autogenous dentin-derived ABG has been considered as the composition of dentin appears to be nearly analogous to that of bone.
OBJECTIVE
This systematic review aims to assess the efficacy of dentin-derived ABG for alveolar augmentation of post-extraction sockets or other alveolar bone defects by evaluating volume gain and histomorphometric data.
MATERIAL AND METHODS
A search of systematic literature was conducted in Pubmed, Scopus, Web of Science, and Embase from database inception to October 2023. The review included both randomized controlled trials (RCT), pilot studies, clinical trials, and retrospective studies reporting on dentin-derived ABG use for alveolar augmentation.
RESULTS
Overall, 298 articles were obtained from the initial search. From these articles, 21 articles met the inclusion criteria and were included for descriptive analysis. All of the studies indicated low risk of bias. Studies of dentin-derived ABG, which used bone-derived grafts as the control group, have shown significantly higher percentages of new bone formation, gain in vertical and horizontal dimensions, and less reduction in dimensions.
CONCLUSIONS
Dentin-derived ABG was effective in volume maintenance, indicating promising results via histomorphometric and radiographic analysis.
PubMed: 38832290
DOI: 10.1016/j.jobcr.2024.05.005 -
Scientific Reports Aug 2023Demineralized dentin matrix (DDM) is an osteoconductive and osteoinductive material that has been successfully used in sinus floor augmentation and alveolar ridge...
Demineralized dentin matrix (DDM) is an osteoconductive and osteoinductive material that has been successfully used in sinus floor augmentation and alveolar ridge augmentation in clinical applications. It releases bone morphogenetic proteins (BMPs) and other growth factors, making DDM a suitable grafting material. However, the granular particle of DDM makes it difficult to anchor into the bone defect area. The aim of this study was to investigate the biological effects and osteoinductivity of the combination of DDM and Fibrin Glue (FG) at an optimal ratio on bone healing from a critical bone defect in an animal model. The mouse osteoblastic cell line (MC3T3-E1) was co-cultured with various ratios of DDM and FG to examine their effects on osteoblast proliferation and differentiation, as indicated by alkaline phosphatase (ALP) activity, osteocalcin (OC) production and mineralized nodules formation. The optimal ratio was then chosen for further study with a rabbit calvarial defective model, in which they were implanted with DDM or DDM-FG1 (1 g: 0.1 ml) and DDM-FG2 (1 g: 0.5 ml) compounds, or left blank for 2, 4, 8 and 12 weeks to investigate soft tissue and new bone regeneration. Micro-CT and histology analysis were used to evaluate the total grafting properties according to the different healing periods. The result from in vitro studies demonstrated that the ratio of 1:0.1 induced more ALP activity and mineralized nodules, while the ratio of 1: 0.5 (DDM-FG combined) induced more osteocalcin (OC) at specific time points. In the animal model, the 3D new bone volume in all DDM-FG treatment groups was significantly greater than that in the blank group at 2, 4, 8 and 12 weeks. Furthermore, the new bone volume was greater in DDM-FG2 when compared to the other groups during the early weeks of the healing period. In histological analysis, clusters of osteoblasts were formed adjacent to the DDM particles, and newly formed bone was observed in all groups, suggesting an osteoinductive property of DDM. Moreover, the greater new collagen synthesis observed at 4 weeks suggested that early bone healing was induced in the DDM-FG2 group. This study demonstrated that at an optimal ratio, the DDM-FG compound enhances osteogenic activities and bone regeneration.
Topics: Mice; Animals; Rabbits; Osteogenesis; Fibrin Tissue Adhesive; Osteocalcin; Sinus Floor Augmentation; Dentin; Bone Regeneration; Cell Differentiation
PubMed: 37573402
DOI: 10.1038/s41598-023-40258-7 -
Biomaterials and Biosystems Sep 2023Mesenchymal stromal/stem cell (MSC) therapies are currently being explored for dental pulp regeneration. As the therapeutic effects of MSCs in tissue repair are mediated...
Mesenchymal stromal/stem cell (MSC) therapies are currently being explored for dental pulp regeneration. As the therapeutic effects of MSCs in tissue repair are mediated mainly through the release of extracellular vesicles (EVs) including exosomes, we investigated here the cellular processes and molecular mechanisms modulated by MSC exosomes in dental pulp regeneration. Using dental pulp cell (DPC) cultures, we demonstrated that MSC exosomes could increase DPC migration, proliferation, and odontogenic differentiation. The enhancement of these cellular processes was mediated through exosomal CD73-mediated adenosine receptor activation of AKT and ERK signaling. Consistent with these observations, MSC exosomes increased the expression of dentin matrix proteins and promoted the formation of dentin-like tissue and bridge-like structures in a rat pulp defect model. These effects were comparable to that of mineral trioxide aggregate (MTA) treatment. MSC exosomes also yielded recellularized pulp-dentin tissues in the root canal of endodontically-treated human premolars, following subcutaneous implantation in the mouse dorsum. Together, our findings suggest that MSC exosomes could exert a multi-faceted effect on DPC functions including migration, proliferation and odontogenic differentiation to promote dental pulp regeneration. This study provides the basis for development of MSC exosomes as a cell-free MSC therapeutic alternative for pulp-dentin regeneration.
PubMed: 37283805
DOI: 10.1016/j.bbiosy.2023.100078 -
BioMed Research International 2023After tooth extraction, alveolar bone resorption is inevitable. This clinical phenomenon challenges dental surgeons aiming to restore esthetic and function. Alveolar... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
After tooth extraction, alveolar bone resorption is inevitable. This clinical phenomenon challenges dental surgeons aiming to restore esthetic and function. Alveolar ridge preservation can be applied to minimize dimensional changes with a new socket grafting material, an autogenous dentin graft, produced by mechanically and chemically processing natural teeth. This study assessed the safety and efficacy of using autogenous dentin biomaterial in alveolar ridge preservation.
MATERIALS AND METHODS
Patients with nonrestorable maxillary anterior teeth bounded by natural sound teeth were included in this study. After a detailed clinical and tomographic examination, eligible participants were randomly allocated into two groups. The control group had spontaneous healing of extraction sockets. The study group had their extraction sockets filled with autogenous dentin biomaterial after processing their extracted retained roots with the KometaBio device. Standardized cone beam computed tomography (CBCT) scans were repeated four months later. A full-thickness mucoperiosteal flap reflection was achieved under local anesthesia to get core biopsies for histomorphometric analysis, and dental implants were placed at the same session.
RESULTS
A total of 32 eligible patients were included in this study ( = 16 in each group). Both groups had significantly higher facial soft tissue thickness after four months than baseline ( < 0.05). However, the study group showed statistically significant lesser dimensional changes than the control group according to the standardized CBCT scans. Furthermore, core biopsies confirmed an excellent remodeling of the autogenous dentin biomaterial in the study group. In comparison, only new thin bone trabeculae-filled sockets were in the control group.
CONCLUSION
Autogenous dentin graft can be safely and successfully used for alveolar ridge preservation. Optimal graft remodeling histologically, better ridge dimensional stability, and uneventful wound healing support its clinical application. This trial is registered with TCTR20220615002.
Topics: Humans; Tooth Socket; Biocompatible Materials; Alveolar Process; Alveolar Bone Loss; Tooth Extraction; Mouth, Edentulous; Dentin; Alveolar Ridge Augmentation
PubMed: 38179035
DOI: 10.1155/2023/7932432 -
Brazilian Dental Journal 2023The objective of this study was to compare the activation of gelatinases in dentin-enamel junction (DEJ) and underlying dentin of permanent teeth after experimental...
The objective of this study was to compare the activation of gelatinases in dentin-enamel junction (DEJ) and underlying dentin of permanent teeth after experimental radiotherapy in conventional and hypofractionated modalities. Newly extracted third molars (n = 15) were divided into three experimental radiotherapy groups: control, conventional (CR), and hypofractionated (HR) (n = 5 per group). After in vitro exposure to ionizing radiation, following standardized protocols for each modality, a gelatinous substrate was incubated on the tooth slices (n = 10 per group). Activation of gelatinases was measured by in situ zymography, expressed in arbitrary fluorescence units (mm2) from three tooth regions: cervical, cuspal, and pit. Fluorescence intensity was compared among radiotherapy protocols and tooth regions in each protocol, considering a significance level of 5%. Considering all tooth regions, the fluorescence intensity of the CR group was higher than the HR and control groups, both in DEJ and underlying dentin (p <0.001). In addition, the fluorescence intensity was higher in underlying dentin when compared to DEJ in all groups (p <0.001). Considering each tooth region, a statistically significant difference between CR and HR was only observed in the pit region of underlying dentin (p <0.001). Significant and positive correlations between fluorescence intensities in DEJ and underlying dentin were also observed (p <0.001). Experimental radiotherapy influenced the activation of gelatinases, as well as exposure to the conventional protocol can trigger a higher activation of gelatinases when compared to hypofractionated, both in DEJ and underlying dentin.
Topics: Humans; Gelatinases; Dental Enamel; Dentin; Molar, Third
PubMed: 38133087
DOI: 10.1590/0103-6440202305542 -
Journal of Translational Medicine Jan 2024Epigenetic factors influence the odontogenic differentiation of dental pulp stem cells and play indispensable roles during tooth development. Some microRNAs can...
BACKGROUND
Epigenetic factors influence the odontogenic differentiation of dental pulp stem cells and play indispensable roles during tooth development. Some microRNAs can epigenetically regulate other epigenetic factors like DNA methyltransferases and histone modification enzymes, functioning as epigenetic-microRNAs. In our previous study, microarray analysis suggested microRNA-93-5p (miR-93-5p) was differentially expressed during the bell stage in human tooth germ. Prediction tools indicated that miR-93-5p may target lysine-specific demethylase 6B (KDM6B). Therefore, we explored the role of miR-93-5p as an epi-miRNA in tooth development and further investigated the underlying mechanisms of miR-93-5p in regulating odontogenic differentiation and dentin formation.
METHODS
The expression pattern of miR-93-5p and KDM6B of dental pulp stem cells (DPSCs) was examined during tooth development and odontogenic differentiation. Dual luciferase reporter and ChIP-qPCR assay were used to validate the target and downstream regulatory genes of miR-93-5p in human DPSCs (hDPSCs). Histological analyses and qPCR assays were conducted for investigating the effects of miR-93-5p mimic and inhibitor on odontogenic differentiation of hDPSCs. A pulpotomy rat model was further established, microCT and histological analyses were performed to explore the effects of KDM6B-overexpression and miR-93-5p inhibition on the formation of tertiary dentin.
RESULTS
The expression level of miR-93-5p decreased as odontoblast differentiated, in parallel with elevated expression of histone demethylase KDM6B. In hDPSCs, miR-93-5p overexpression inhibited the odontogenic differentiation and vice versa. MiR-93-5p targeted 3' untranslated region (UTR) of KDM6B, thereby inhibiting its protein translation. Furthermore, KDM6B bound the promoter region of BMP2 to demethylate H3K27me3 marks and thus upregulated BMP2 transcription. In the rat pulpotomy model, KDM6B-overexpression or miR-93-5p inhibition suppressed H3K27me3 level in DPSCs and consequently promoted the formation of tertiary dentin.
CONCLUSIONS
MiR-93-5p targets epigenetic regulator KDM6B and regulates H3K27me3 marks on BMP2 promoters, thus modulating the odontogenic differentiation of DPSCs and dentin formation.
Topics: Humans; Rats; Animals; Histones; Stem Cells; Cell Differentiation; MicroRNAs; Dentin; Cells, Cultured; Jumonji Domain-Containing Histone Demethylases
PubMed: 38218880
DOI: 10.1186/s12967-024-04862-z -
Journal of Dentistry Mar 2024To investigate distribution of affected teeth and severity of molar-incisor hypomineralisation (MIH) in 8-9-year-old children. A second aim was to study association...
OBJECTIVES
To investigate distribution of affected teeth and severity of molar-incisor hypomineralisation (MIH) in 8-9-year-old children. A second aim was to study association between severity of MIH and hypersensitivity, caries, and affection of incisors and second primary molars (SPM).
METHODS
A total of 3013 children in one age cohort participated in a cross-sectional study, of which 851 children were diagnosed with MIH. A majority of these children were re-examined and MIH diagnosis based on the European Academy of Paediatric Dentistry criteria was confirmed in 538 children. The re-examinations were undertaken at the local clinics by one calibrated dentist. Data were tested with bivariate logistic regression analysis. Results were reported using frequencies, proportions, odds ratios (OR) and confidence intervals (CI).
RESULTS
Almost half of the children with MIH (46.8 %) had at least one severely affected molar. Incisors were affected in 51.9 % of children with MIH, and the prevalence was higher in children with severe affection (57.4 %, p < 0.01). Among children with MIH, second primary molars were affected in 29.6 %, hypersensitivity in at least one first permanent molar was reported by 25.8 and 30.8 % had caries extending to dentine. Children classified with severe MIH were more likely to suffer from hypersensitivity (OR 5.62, 95 % CI 3.61-8.74) and dentine caries (OR 10.32, 95 % CI 6.46-16.50) than children with mild MIH.
CONCLUSION
Prevalence of hypomineralised incisors and SPM were high in the studied children with MIH. Children with severe MIH had higher probability of incisor affection, dentin caries and hypersensitivity.
CLINICAL SIGNIFICANCE
This study highlights the importance of understanding the association between MIH, caries and hypersensitivity, especially in children with severe MIH. These children need extensive and individualized care in the dental services to prevent caries and pain.
Topics: Child; Humans; Dental Enamel Hypoplasia; Cross-Sectional Studies; Dental Caries Susceptibility; Molar Hypomineralization; Dental Caries; Molar; Prevalence
PubMed: 38331377
DOI: 10.1016/j.jdent.2024.104881 -
International Dental Journal Feb 2024The aim of this research was to investigate the functions of Piezo channels in dentin defect, including mechanical signalling and odontoblast responses.
OBJECTIVES
The aim of this research was to investigate the functions of Piezo channels in dentin defect, including mechanical signalling and odontoblast responses.
METHODS
Rat dentin-defect models were constructed, and spatiotemporal expression of Piezo proteins was detected in the pulpo-dentinal complex. Real-time polymerase chain reaction (rtPCR) was used to investigate the functional expression pattern of Piezo channels in odontoblasts. Moreover, RNA interference technology was employed to uncover the underlying mechanisms of the Piezo-driven inflammatory response and repair under fluid shear stress (FSS) conditions in vitro.
RESULTS
Piezo1 and Piezo2 were found to be widely expressed in the odontoblast layer and dental pulp in the rat dentin-defect model during the end stage of reparative dentin formation. The expression levels of the Piezo1 and Piezo2 genes in MDPC-23 cells were high in the initial stage under FSS loading and then decreased over time. Moreover, the expression trends of inflammatory, odontogenic, and mineralisation genes were generally contrary to those of Piezo1 and Piezo2 over time. After silencing of Piezo1/Piezo2, FSS stimulation resulted in significantly higher expression of inflammatory, odontogenesis, and mineralisation genes in MDPC-23 cells. Finally, the expression of genes involved in the integrin β1/ERK1 and Wnt5b/β-catenin signalling pathways was changed in response to RNA silencing of Piezo1 and Piezo2.
CONCLUSIONS
Piezo1 and Piezo2 may be involved in regulating the expression of inflammatory and odontogenic genes in odontoblasts stimulated by FSS.
Topics: Rats; Humans; Animals; Odontoblasts
PubMed: 37833209
DOI: 10.1016/j.identj.2023.07.002 -
European Review For Medical and... Oct 2023To evaluate the effects of various surface pretreatment methods, including H2SO4, Riboflavin, and Al2O3, as well as different luting cement types, namely Methyl... (Randomized Controlled Trial)
Randomized Controlled Trial
The impact of PEEK pretreatment using H2SO4, riboflavin, and aluminum trioxide on the extrusion bond strength to canal dentin luted with Polymethyl methacrylate and resin-based composite cement.
OBJECTIVE
To evaluate the effects of various surface pretreatment methods, including H2SO4, Riboflavin, and Al2O3, as well as different luting cement types, namely Methyl Methacrylate based Cement (MMBC) and composite-based cement (CBC), on the extrusion bond strength (EBS) of poly-ether-ether-ketone (PEEK) posts bonded to canal dentin.
MATERIALS AND METHODS
This study involved 120 single-rooted human premolar teeth that underwent endodontic treatment. Following root canal preparation, PEEK posts were fabricated from PEEK blanks using a CAD-CAM system, resulting in a total of 120 posts. The posts were randomly assigned to one of four groups based on their post-surface conditioning: Group A H2SO4, Group B RF, Group C Al2O3, and Group D (NC), each consisting of 30 posts. Within each group, there were two subgroups based on the type of luting cement used for bonding. Subgroups A1, B1, C1, and D1 (n=15 each) utilized CBC, while Subgroups A2, B2, C2, and D2 (n=15 each) used MMBC.The bond strength between the PEEK posts and root dentin was assessed using a universal testing machine, and the failure modes were examined under a stereomicroscope. Statistical analysis, including one-way analysis of variance (ANOVA) and Tukey's Post Hoc test with a significance level of p=0.05, was performed to analyze the data and evaluate the effects of surface treatment and luting cement type on the bond strength.
RESULTS
Group B2, which underwent RF conditioning followed by Super-Bond C&B cement application, exhibited the highest bond strength scores at the coronal section (9.57±0.67 MPa). On the other hand, Group D1, which had no conditioning (NC) and used Panavia® V5 cement, showed the lowest EBS at the apical third (2.39±0.72 MPa). The overall results indicate that the different conditioning regimens and luting cement types did not significantly influence the bond strength of PEEK posts to root dentin (p>0.05).
CONCLUSIONS
Riboflavin activated by photodynamic therapy (PDT) and H2SO4 can be effective surface conditioners for PEEK posts. These treatments have shown potential for enhancing the bond strength between PEEK and resin cement. Additionally, the study revealed that MMA-based cement outperformed composite-based cement in terms of bond integrity with PEEK posts.
Topics: Humans; Aluminum; Aluminum Oxide; Bone Cements; Composite Resins; Dentin; Ether; Ethers; Ethyl Ethers; Glass; Ketones; Materials Testing; Polymethyl Methacrylate; Riboflavin
PubMed: 37916329
DOI: 10.26355/eurrev_202310_34135