The bone morphogenetic protein (BMP) family has numerous members that play various regulatory roles in cell differentiation and tissue morphogenesis. They can precisely regulate cell proliferation, differentiation, apoptosis, and other processes. Notably, the members of the BMP family, such as BMP1, BMP2, BMP4, and BMP7, etc., play significant roles in the odontoblast differentiation. By delving into the expression and regulatory mechanisms of BMP during tooth development and reparative regeneration, a deeper understanding of the biological processes involved in tooth formation can be gained, providing theoretical support for the repair and regeneration of dental defects. However, the clinical application of BMP still faces numerous challenges, and how to precisely regulate the expression and activity of BMP during odontogenic differentiation remains to be further studied. In this review, the research progress in the role of the BMP family members for odontogenic differentiation was summarized, with a view to providing some reference for exploring new therapeutic strategies of BMP application in the repair and regeneration of dental defect.

In recent years, problems such as the devitalization of dental pulp and the increased brittleness and fragility of teeth after root canal treatment have attracted more and more attention. Therefore, pulp regeneration has become the focus of research in endodontics and periapical disease, in which vascularization is of paramount importance. It is found that peptide hydrogel scaffolds have been widely applied because of their properties of impacting cell behavior, promoting angiogenesis, and being adaptable. In this review paper, the research progress of the application of peptide hydrogel in the vascularization of pulp regeneration and the properties of various peptide hydrogels were summarized to provide a reference for the further application of peptide hydrogel in pulp regeneration.

Objective:To prepare a peptide fluorescent probe based on aggregation-induced emission and to investigate its application in the detection of early caries.Methods:Eight aspartate-serine-serine (DSS) were combined with aggregation-induced emission material to prepare peptide fluorescent probes, and an artificial demineralization model was established in vitro. The samples were immersed in the peptide fluorescent probe solution for 1 min, and a fluorescence imaging system was applied to examine the tooth samples and collect images and fluorescence data. Scanning electron microscopy was also applied to observe the phenotype of the teeth, and electron microscopy was applied to detect the calcium-phosphorus ratio on the enamel surface of the teeth. Polarized light microscopy was also applied to observe the enamel area of the teeth. Results:The fluorescence intensity of demineralized teeth was clearly observed to be lower than that of normal teeth in the peptide fluorescent probe-treated area, and the difference was statistically significant ( P < 0.05). The results of scanning electron microscopy showed that the enamel surface of the demineralized group had more irregular pores, while the enamel surface of the undemineralized group was flatter with only some irregular accumulation of flakes. The results of polarized light microscopy showed that a clear birefringence could be observed in the enamel region of normal teeth, while a black area or the disappearance of the birefringence effect accompanied by a partial black dark shadow could be observed in the enamel region of demineralized teeth. Conclusions:An aggregation-induced luminescence-based peptide fluorescent probe was successfully prepared, which can precisely localize the enamel and show some application value in early caries detection.

With the improvement of people's living standard and the strengthening of people's recognition of dental caries prevention and treatment, enamel remineralization has attracted extensive attention. Fluoride, bioactive glass and casein phosphopeptide-amorphic calcium phosphate (CPP-ACP) are the most widely studied remineralisation agents at present, which have a certain effect of promoting enamel remineralization. The results of different studies shown that the effect of CPP-ACP combined with fluoride was quite different, which may be affected by many factors. In this paper, the recent progress of the combined application of CPP-ACP and fluoride on enamel remineralization was reviewed, and various influencing factors were analyzed in order to provide references for future experimental design and clinical applications.

Orthodontic tooth movement is achieved by remodeling periodontal ligament, alveolar bone and other periodontal tissues in response to mechanical loading. The periodontal ligament is the fibrous connective tissue connecting cementum and alveolar bone, which plays an important role in the transmission, absorption and dispersion of supporting teeth and biting force. When orthodontic forces are applied to the teeth, load transfer occurs from the tooth through the periodontal ligament to the alveolar bone. The remodeling of periodontal ligament interacts with the alveolar bone formation and absorption alternately. As the initial factor of orthodontic tooth movement, the stress/strain of periodontal ligament is involved in the process of alveolar bone remodeling and affects the direction and speed of tooth movement. Therefore, the biomechanical properties of the periodontal ligament have received extensive attention. In this paper, the related researches on the structural changes and biomechanical characteristics of the periodontal ligament during orthodontic tooth movement were reviewed as well as the researches on the mechanical constitutive model of the periodontal ligament. The mechanical response and biomechanical mechanism of the periodontal ligament were discussed in order to provide a theoretical basis for accurate numerical simulation of orthodontic tooth movement.

Pulp necrosis can cause increased tooth fragility and easy fracture, and hinder the sustainable development of young permanent teeth. Therefore, pulp regeneration therapy has important clinical significance. However, due to the complicated and varied anatomical structure of the pulp tissue, and various components such as nerves and blood vessels, there are many challenges in dental pulp regeneration strategy. In this paper, the recent research progress in the application of dental pulp tissue construction and transplantation by tissue engineering method was reviewed, and the selection of suitable scaffold materials and the construction of dental pulp tissue were discussed. The functional characteristics of scaffold materials were described,such as sodium alginate, chitosan, hyaluronic acid, collagen, gelatin, fibrous protein, silk fibroin, peptides and self-assembled peptides, polylactic acid, polyglycolic acid and their copolymers. In addition, the functions and characteristics of these materials were briefly introduced, as well as the functional modification with growth factors and other biological matrix extract involvement, and functional improvement of the composite scaffolds with complementary effects.Combined with the requirements of clinical operability, the composition design and functional characteristics of the injectable hydrogel scaffolds consisted of hydrophilic composite materials and/or modified with hydrophilic groups were also discussed.This review paper would be useful in providing some reference for the future research and exploration of dental pulp regeneration.

The traditional treatment of maxillofacial tumors includes surgery and chemoradiotherapy. Surgery carries a high risk,and large bone defects are difficult to repair themselves. Besides, chemoradiotherapy can bring serious side effects. Therefore, how to repair the bone defects after maxillofacial tumor surgery and prevent tumor recurrence has become a major clinical challenge. In recent years, photothermal therapy has attracted much attention because of its low invasion, high efficiency, and no side effects. More and more photothermal materials have emerged and been applied in photothermal therapy. In order to treat tumor-related bone defects, many studies use three-dimensional printing technology to prepare photothermal functionalized scaffold to repair bone defects and prevent the recurrence of tumors. Based on photothermal therapy, the review states the photothermal materials, bone repair materials and photothermal functionalized scaffolds in the treatment of maxillofacial tumors at home and abroad, and provides a new way to solve the clinical challenge of bone defect and tumor recurrence after maxillofacial tumor surgery.

With the rapid development of cell biology and biological materials, the dentine-pulp complex regeneration research has gone further. Scaffolds play important roles in the construction of tissue engineered dentine-pulp complex. At present, scaffolds used in dentine-pulp complex regeneration include not only natural biological materials and synthetic biomaterials, but also various composite materials and cell- or body-based carrier materials. In this paper, the latest research status of various scaffolds for dentine-pulp complex regeneration were reviewed. The advantages and problems of these scaffolds were analyzed. The future development direction was predicted.

Objective To examine the effects of gross tumor volume (GTV) and radiation dose on the prognosis of hepatocellular carcinoma (HCC) patients treated with whole body gamma knife.Methods The clinical data of 69 HCC patients who underwent body gamma knife treatment from January 2012 to June 2015 in the Radiotherapy Center of the PLA General Hospital were retrospectively reviewed.Based on a 50% or 60% isodose coverage of the planning target volume (PTV), patients were treated with a radiation dose of 4-5 Gy per fraction, and a total marginal dose of 36-50 Gy (median dose 45 Gy).Short-term efficacy, overall survival (OS), and the adverse effect of the treatment were evaluated.The optimal cut-off tumor volume was identified using the receiver operating characteristic curve, and survival was determined by the Kaplan-Meier method.Univariate and multivariate analyses were performed using the log-rank test and Cox proportional hazards regression model, respectively.Results The overall short-term response rate of the 69 patients was 67%.The 1-and 2-year OS rates were 62% and 40%, respectively, with a median survival of 18.6 months.The multivariate analysis showed that gross tumor volume (GTV)<93 cm3(P=0.013) and short-term efficacy of radiotherapy (P=0.000) were significant independent prognostic factors for survival.When GTV was<93 cm3, prognosis was significantly better in patients treated with a dose of ≥45 Gy than in those with<45 Gy (P=0.019).In contrast, radiation dose had no significant effect on survival among patients with GTV>93 cm3(P=0.665).Conclusions GTV is an independent prognostic factor for overall survival of HCC patients.Although high-dose radiotherapy provides survival benefits to patients with small GTV, it is not necessarily suitable for patients with large GTV.

Objective To evaluate the dosimetric difference between fixed-field static intensity-modulated radiotherapy (IMRT), fixed-field dynamic multileaf collimator (DMLC), and volumetric modulated arc therapy (VMAT), all of which involve supraclavicular and infraclavicular regions, in breast cancer patients after breast-conserving surgery.Methods This study included 14 female patients with breast cancer who received radiotherapy after breast-conserving surgery in our hospital from October 2012 to April 2016.The radiation field included the chest wall and supraclavicular and infraclavicular regions.IMRT, DMLC, and VMAT plans were generated for each patient while using identical optimization conditions.The doses to planning target volume (PTV) and organs at risk (OARs) were compared based on dose-volume histogram (DVH);one-way analysis of variance or nonparametric Wilcoxon rank test was used for comparison.Results For the dose distribution of PTV, VMAT achieved the best V95, V98, CI, and HI (P<0.009).Concerning the doses to OARs, VMAT achieved the best V5, V20, and Dmean of the ipsilateral lung and the best V5 and Dmean of the contralateral lung (P<0.022).Dmean of the spinal cord was significantly lower in VMAT than in IMRT and DMLC (P=0.004).Conclusions VMAT is preferred for the patients with breast cancer to be treated with radiotherapy involving supraclavicular and infraclavicular regions after breast-conserving surgery.It can improve the dose distribution of target and reduce the doses to organs at risk and radiotherapy toxicities.