Abbasali Khademi

Bone loss in the craniofacial region can result from various causes, requiring grafting for restoration. Each type of bone graft has advantages and disadvantages. In recent years, an increasing number of clinical research has used extracted teeth as graft biomaterials. This study aimed to outline the use of teeth as bone graft material, describe a general protocol for producing tooth graft material, compare various manufacturing methods, and assess tooth-derived grafts relative to other bone graft materials. The review was based on electronic database searches in Scopus, PubMed, Cochrane, Web of Science, and Google Scholar, using various combinations of keywords such as "autogenous graft," "autologous graft," "human dentin," "dentin matrix," "tooth graft," "demineralized dentin matrix," and related terms applied to titles, abstracts, and keywords. Tooth-derived grafts demonstrate promising outcomes comparable to conventional bone graft materials. However, further research is necessary to standardize protocols and validate clinical applications.

Aim: This scoping review aimed to evaluate effectiveness of using tooth graft (TG) mixture with platelet‐rich fibrin (PRF), examining their roles in oral bone reconstruction and preservation, and evaluating the clinical and histopathological outcomes associated with this approach. Material and Methods: Articles were searched in Scopus, Medline, Web of Science, ProQuest, and Google Scholar up to November 2024. The search was guided by the PCC framework: Population: alveolar bone and calvaria bone defects; Concept: the use of a TG mixture with PRF as a bone graft material; Context: clinical and histopathological outcomes of oral bone reconstruction and preservation. Two independent researchers carried out the screening, study selection, and data extraction processes. Results: Use of the PRF and TG mixture for socket preservation is superior to using each of these biomaterials individually. However, in the context of bone reconstruction, although all studies confirm new bone formation, the superiority of this mixture over the separate use of each biomaterial remains uncertain. Additionally, all studies confirm the increase in bone density and new bone formation aimed at implant placement. Conclusion: The majority of studies have reported that the PRF and TG mixture enhances both the quality and quantity of bone.

Background: Postoperative pain has remained a challenge for clinicians. This randomized superiority trial compared the levels of postoperative pain following the use of gutta-percha (GP) and sealer or mineral trioxide aggregate (MTA) as root canal filling materials in teeth with asymptomatic apical periodontitis. Methods: A total of 119 patients were initially evaluated in this two-arm, parallel-group, single-blind, superiority randomized trial. The inclusion criteria were participants aged 18–65 years with single-canal premolars diagnosed with asymptomatic apical periodontitis. The participants were finally divided into two groups using the permuted block randomization method. In the GP group (N = 46), the cleaned and shaped root canals were filled with gutta-percha and AH Plus sealer, while in the MTA group (N = 48), the cleaned and shaped root canals were filled with an MTA apical filling and a coronal gutta-percha and sealer. Patient pain level was measured 6, 12, 24, 48, and 72 h postoperatively using a 10-point visual analog scale (VAS). The data were analyzed by the chi-square, independent t, Friedman, and Mann-Whitney U tests. Results: The mean of VAS scores decreased significantly over time in both groups (P < 0.001). The mean VAS scores were significantly lower in the MTA filling group than in the other group (P < 0.05). Female patients reported higher VAS scores at 6- and 12-hour periods in both groups (P < 0.05). Conclusion: MTA as a root canal filling material might be a valuable option for clinicians due to its low postoperative pain. Trial registration: The trial protocol was registered at the Registry of Clinical Trials (IRCT20191104045331N1).

Background: Human dental pulp-derived mesenchymal stem cells (hDP-MSCs), which include human dental pulp stem cells (hDPSCs) and stem cells from human exfoliated deciduous teeth (SHEDs), are promising cell sources for regenerative therapies. Nevertheless, a lack of knowledge relating to the mechanisms regulating their differentiation has limited their clinical application. microRNAs (miRNAs) are important regulatory molecules in cellular processes including cell differentiation. This systematic review aims to provide a panel of miRNAs that regulate the differentiation of hDP-MSCs including hDPSCs and SHEDs. Additionally, bioinformatic analyses were conducted to discover target genes, signaling pathways and gene ontologies associated with the identified miRNAs.Methods: A literature search was performed in MEDLINE (via PubMed), Web of Science, Scopus, Embase and Cochrane Library. Experimental studies assessing the promotive/suppressive effect of miRNAs on the differentiation of hDP-MSCs and studies evaluating changes to the expression of miRNAs during the differentiation of hDP-MSCs were included. miRNAs involved in odontogenic/osteogenic differentiation were then included in a bioinformatic analysis. A miRNA-mRNA network was constructed, and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed. A protein–protein interaction (PPI) network was also constructed.Results: Of 766 initially identified records through database searching, 42 and 36 studies were included in qualitative synthesis and bioinformatic analyses, respectively. Thirteen miRNAs promoted and 17 suppressed odontogenic/osteogenic differentiation of hDP-MSCs. hsa-miR-140-5p, hsa-miR-218 and hsa-miR-143 were more frequently reported suppressing the odontogenic/osteogenic differentiation of hDP-MSCs. hsa-miR-221 and hsa-miR-124 promoted and hsa-miR-140-5p inhibited neuronal differentiation, hsa-miR-26a-5p promoted and hsa-miR-424 suppressed angiogenic differentiation, and hsa-miR-135 and hsa-miR-143 inhibited differentiation within myogenic lineages. A miRNA-mRNA network including 1890 nodes and 2171 edges was constructed. KEGG pathway analysis revealed MAPK, PI3K-Akt and FoxO as key signaling pathways involved in the odontogenic/osteogenic differentiation of hDP-MSCs.Conclusions: The findings of this systematic review support the potential application of the specific miRNAs to regulate the directed differentiation of hDP-MSCs in the field of regenerative therapies.

Oral and maxillofacial tissue defects caused by trauma, tumor reactions, congenital anomalies, ischemic diseases, infectious diseases, surgical resection, and odontogenic cysts present a formidable challenge for reconstruction. Tissue regeneration using functional biomaterials and cell therapy strategies has raised great concerns in the treatment of damaged tissue during the past few decades. However, during biomaterials implantation and cell transplantation, the production of excessive reactive oxygen species (ROS) may hinder tissue repair as it commonly causes severe tissue injuries leading to the cell damage. These products exist in form of oxidant molecules such as hydrogen peroxide, superoxide ions, hydroxyl radicals, and nitrogen oxide. These days, many scientists have focused on the application of ROS-scavenging components in the body during the tissue regeneration process. One of these scavenging components is antioxidants, which are beneficial materials for the treatment of damaged tissues and keeping tissues safe against free radicals. Antioxidants are divided into natural and synthetic sources. In the current review article, different antioxidant sources and their mechanism of action are discussed. The applications of antioxidants in the regeneration of oral and maxillofacial tissues, including hard tissues of cranial, alveolar bone, dental tissue, oral soft tissue (dental pulp, periodontal soft tissue), facial nerve, and cartilage tissues, are also highlighted in the following parts.

Objectives. The percentage of failure of endodontically treated maxillary molars is relatively high; one main reason is that the second mesiobuccal canal (MB2) is missing. Some techniques have been proposed for detection of the MB2. This study was aimed at assessing the diagnostic accuracy and agreement of the dental microscope and cone-beam computed tomography (CBCT) in comparison with microcomputed tomography (micro-CT) for detection of the MB2 of maxillary first molars in vitro. Materials and Methods. This in vitro, experimental study evaluated 71 permanent maxillary first molars that were stored in 100% humidity at room temperature. The teeth were mounted in 9 silicone dental arches to the level of their cementoenamel junction (8 teeth in each arch). The blocks underwent CBCT in a XG3D scanner. Access cavity was then prepared, and the teeth were inspected by a surgical microscope for negotiation of the MB2. Also, micro-CT images were obtained from the teeth to serve as the gold standard. CBCT and micro-CT images were observed by two examiners twice with a 2-week interval. Results. The frequency of the MB2 detected by dental microscope was significantly lower than micro-CT ( ) and CBCT ( ); no significant difference existed between micro-CT and CBCT in this respect. The sensitivity, specificity, positive predictive value, and negative predictive value of CBCT for detection of MB2 were 92.6%, 100%, 100%, and 81%, respectively. Conclusion. CBCT is superior to the dental microscope for detection of the MB2 of maxillary first molars and can be used for this purpose in the clinical setting with adequate accuracy.

Background: Incorporating an additive into lidocaine is a method to enhance the efficacy of the inferior alveolar nerve block (IANB) in mandibular posterior teeth.Objectives: To assess the efficacy of incorporating additives into lidocaine in the success rate of IANB for teeth with the diagnosis of normal pulp (NP) or symptomatic irreversible pulpitis (SIP).Methods: Randomized controlled trials (RCTs) assessing the incorporation of additives into lidocaine on the pulpal anaesthesia success rate of mandibular posterior teeth were searched in PubMed, Scopus, Web of Science, Ovid, EBSCO, Embase, and Cochrane databases up to 1 December 2021. The risk of bias (RoB) was assessed by the Cochrane Risk of Bias Tool. A random‐effects model was employed to calculate the pooled risk ratio (RR) with a 95% confidence interval (CI), using STATA 16. The trial sequential analysis (TSA) was applied to calculate the required information size (RIS). The Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach was used to assess the certainty of the evidence.Results: Of 6966 records retrieved initially, 14 trials (8 for NP and 6 for SIP groups) were included in qualitative and quantitative syntheses. All trials were categorized as low and unclear RoB for NP and SIP groups, respectively. In the NP group, with 307 participants, no significant effect was observed for additives incorporated into lidocaine (RR: 0.84; 95% CI: 0.53‒1.32; I² = 98%). Subgroup analysis revealed that adding mannitol led to a higher success rate (RR = 1.24; 95% CI: 1.15–1.34; I² = 7.16%). In the SIP group, with 434 participants, no significant effect was shown when the additives were incorporated (RR = 1.22; 95% CI: 0.98–1.52; I² = 0%). Likewise, in subgroup analysis, incorporating mannitol or sodium bicarbonate demonstrated no significant effect (RR = 1.76; 95% CI: 0.93–3.32; I² = 18.41% and RR = 1.06; 95% CI: 0.65–1.72; I² = 53.5%, respectively).Discussion: TSA revealed that the outcome was “inconclusive” for each group. The certainty of the evidence was graded as “very low” and “low” for NP and SIP groups, respectively.Conclusions: The very low to low certainty of evidence indicated that incorporating additives into lidocaine did not increase the efficacy of IANB and supplemental injections are still necessary to help practitioners achieve painless dentistry.Registration: PROSPERO database (CRD42020132585).

Y Objective: The aim of present study was to isolate and differentiate human adipose-derived stem cells (ASCs) into odontoblast-like cells. Materials and Methods: In this experimental study, human adipose tissues were taken from the buccal fat pad of three individuals (mean age: 24.6 +/- 2.1 years). The tissues were transferred to a laboratory in a sterile culture medium, divided into small pieces and digested by collagenase I (2 mg/mL, 60-90 minutes). ASCs were isolated by passing the cell suspension through cell strainers (70 and 40 mu m), followed by incubation at 37 degrees C and 5% CO2 in Dulbecco's modified eagle medium (DMEM) supplemented with fetal bovine serum (FBS 5%) and penicillin/streptomycin (P/S). After three passages, the ASCs were harvested. Subsequently, flow cytometry and reverse transcriptase polymerase chain reaction (RT-PCR) were used to detect expression levels of NANOG and OCT4 to evaluate stemness. Then, a differentiation medium that included high-glucose DMEM supplemented with 10% FBS, dexamethasone (10 nM), sodium beta-glycerophosphate (5 mM) and ascorbic acid (100 mu M) was added. The cells were cultivated for four weeks, and the odontogenic medium was changed every two days. Cell differentiation was evaluated with Alizarin red staining and expressions of collagen I (COL1A1), dentin sialophosphoprotein (DSPP) and dentin matrix protein-1 (DMP1). Results: The ASCs were effectively and easily isolated. They were negative for CD45 and positive for the CD105 and CD73 markers. The ASCs expressed OCT4 and NANOG. Differentiated cells highly expressed DSPP, COL1A1 and DMP1. Alizarin red staining revealed a positive reaction for calcium deposition. Conclusion: ASCs were isolated successfully in high numbers from the buccal fat pad of human volunteers and were differentiated into odontoblast-like cells. These ASCs could be considered a new source of cells for use in regenerative endodontic treatments.