[Diagnosis and treatment planning of traumatic dental injury].

Traumatic dental injury (TDI), one of the common dental diseases, is defined as acute injuries to tooth hard tissues, dental pulp and/or periodontal tissues caused by sudden forces. Based on the Guidelines for the Management of TDI by International Association of Dental Traumatology (2012) and the Recommended Guidelines of the American Association of Endodontists for the Treatment of TDI (2013) for the permanent teeth, and combined with the authors' clinical experiences, the contemporary classification and clinical perspective of TDI were introduced in detail. Dental clinicians should understand and master the international guidelines for the management of TDI, including proper diagnosis, standardized treatments and regular follow-up, so as to obtain the favorable outcomes.

[Clinical observation of three-dimensional printing donor tooth model in peri-operative period of autotransplantation of tooth].

Objective: To prepare a three-dimensional (3D) printing donor tooth model and to observe its application in the peri-operative period. Methods: In part one, 192 cases (2017.9-2019.8) from Department of Oral & Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University ï¼»107 males and 85 females, age (34.2±10.7) yearsï¼½ which need autotransplantation of teeth (ATT) were collected. Whether the donor teeth can be completely extracted was predicted through clinical and imaging examination (first prediction). The second prediction was supplemented by the three-dimensional printing model of the donor teeth. Each of the prediction was compared with the actual results and the coincidence rate was calculated. In part two, 64 cases (2017.9-2019.8) from Department of Oral & Maxillofacial Surgery, School of Stomatology, The Fourth Military Medical University ï¼»28 males, 36 females, age (30.2±8.3) yearsï¼½ which need ATT were randomly divided into the model group and the donor group. The time of alveolar fossa preparation, time of donor tooth in vitro, times of trial implantation and time of pulptomy and root canal location were recorded respectively. Results: In part one, the coincidence rate between the second prediction and the actual results ï¼»97.4%(187/192)ï¼½ was significantly higher than that of the first prediction ï¼»93.2%(179/192)ï¼½ (P<0.05). In part two, the preparation time of the alveolar fossa in the maxillary and mandibular were (18.8±4.6) and (22.7±3.4) min, the time of the teeth in vitro were (3.0±0.6) and (2.1±0.6) min, the times of trial implantation were (1.3±0.8) and (1.0±0.9), and the time of pulpotomy and root canal location were (4.3±0.6) and (4.0±0.5) min. All values in the model groups were better than those in the donor group (P<0.05). Conclusions: The 3D printing model is accurate. It can be used in autogenous tooth transplantation to shorten the preparation time of alveolar fossa and time of donor tooth in vitro, and reduce the times of trial implantation of donor teeth, and to help to improve the prediction accuracy of complete extraction of donor teeth and the time of pulpotomy and root canal location.

[Clinical consideration and strategy on endodontic microsurgery].

Root canal therapy is the most widely used method to treat the teeth with pulpal and periapical disorders. However, due to the complexity of root canal system, the existence of extraradicular biofilms and occurrence of true cyst, some teeth with pulpal and periapical diseases couldn't be treated effectively by non-surgical therapies. Then the combination of the surgical treatment, i.e., endodontic surgery, is necessary. The endodontic microsurgery, under the magnification and illumination provided by the dental operation microscope and with the proper use of micro instruments, ultrasonic retrotips and bioceramics root end filling materials, can treat the teeth with pulpal or periapical disorders precisely and less traumatically with high success rate. This article reviews the indications, contraindications, clinical strategy and latest advancement in endodontic microsurgery.

Biofunctionalization of titanium surface with multilayer films modified by heparin-VEGF-fibronectin complex to improve endothelial cell proliferation and blood compatibility.

In-stent restenosis and subsequent thrombosis remain a significant complication following the implantation of coronary stents. Different approaches have been used in developing novel coronary stents to protect against thrombosis and minimize restenosis. In the present study, we designed a biomacromolecular layer-by-layer coating with heparin, vascular endothelial growth factor (VEGF), and fibronectin onto nickel-free titanium surface to improve blood compatibility and endothelial cell proliferation. The multilayer assembling process was monitored by water contact angle and surface plasmon resonance, respectively. With increasing the number of layers, the deposition of polyelectrolyte as self-assembled ultrathin multilayer films showed linear growth of absorbance. In vitro blood compatibility results revealed that the fabricated layers prolonged activated partial thrombin time and prothrombin time, reduced platelets activation and aggregation, and reduced blood hemolysis rate. Cell adhesion and growth results showed that the assembled multilayer films significantly promoted cell attachment and growth, and the endothelialization property of the multilayer films was preferable compared with the untreated titanium disk. In conclusion, these results suggest that titanium surface modification using biofunctional multilayer films composed of heparin, VEGF, and fibronectin may serve as a potential approach to inhibit thrombosis and promote re-endothelialization of cardiovascular stents.

MEPE activated by furin promotes pulpal cell adhesion.

UNLABELLED: Matrix extracellular phosphoglycoprotein (MEPE) is predominantly expressed in osteoblasts, osteocytes, and odontoblasts and plays key biological roles in bone and dentin metabolism. Post-translational modifications are essential for its activation. This study tested the hypothesis that MEPE is activated through proteolytic processing by furin in dental pulp. MEPE was present in three sizes, 1 full-length and 2 cleaved fragments; the cleavage site was 146R↓147. The proprotein convertase family, particularly furin, was a candidate enzyme. Introducing a substitution at the cleavage site inhibited hydrolysis, but there was no cleavage of MEPE expressed in furin-deficient LoVo cells. Therefore, furin is a strong candidate for the proteolytic cleavage of MEPE. The C-terminal cleavage product promoted cell adhesion via its RGD motif. These results indicate that proteolytic processing by furin may activate MEPE during its secretion from odontoblasts and may play important roles in dentinogenesis and pulpal homeostasis. ABBREVIATIONS: MEPE, matrix extracellular phosphoglycoprotein; PTM, post-translational modifications; OLC, odontoblast-lineage cells.

Effect of IL-1ra on human dental pulp cells and pulpal inflammation.

AIM: This study was conducted to investigate the effect of interleukin-1 receptor antagonist (IL-1ra) on the LPS-induced interleukin-1beta (IL-1beta) synthesis in human dental pulp cells and to assess the role of IL-1ra in pulpal inflammation. METHODS: IL-1beta from human dental pulp cells (HDP) was measured by sandwich ELISA; IL-1ra expression in pulpal tissue was detected by immunohistochemical staining. RESULTS: Stimulation of HDP with increasing concentrations of FnLPS resulted in dose-dependent IL-1beta production. The addition of IL-1ra reduced FnLPS-induced IL-1beta synthesis in human dental pulp cells. Significant inhibition of the FnLPS-induced IL-1beta synthesis was observed when IL-1ra was added before treating with FnLPS for 60 min. Large numbers of IL-1ra positive neutrophils, plasmacytes, endothelial cells and lymphocytes were observed in inflamed pulp tissue. CONCLUSIONS: IL-1ra could reduce LPS-stimulated IL-1beta synthesis, suggesting that IL-1ra may play a role in pulpitis.