Hua xi kou qiang yi xue za zhi = Huaxi kouqiang yixue zazhi = West China journal of stomatology最新文献

Long-term dental implant stability is governed by the synergistic regulation of multiple factors, with occlusal parameters and marginal bone loss (MBL) progression being of paramount importance. Progressive MBL undermines mechanical retention, predisposing implants to micromotion and jeopardizing their long-term survival. Accumulating evidence has revealed that homeostatic occlusion imbalance, characterized by excessive occlusal loading, aberrant occlusal contacts, and dysfunctional guidance, significantly increases the incidence of peri-implant bone loss, thereby disrupting biomechanical homeostasis. Therefore, this manuscript delineates the mechanistic role of steady-state occlusal imbalance in driving peri-implant MBL and proposes a homeostatic occlusion-based strategy for preventing and controlling such bone loss, aiming to enhance the long-term stability of dental implants.

Objectives: To evaluate the accuracy of a self-developed extraoral scanning system based on four-camera stereophotogrammetric technology in the acquisition of three-dimensional positional information on dental implants and conduct a comparative study involving an intraoral scanning system.

Methods: With the use of an in vitro edentulous jaw model with implants, extraoral (experimental group) and intraoral (control group) scanning systems were employed to obtain STL (Standard Tessellation Language) datasets containing three-dimensional morphological and positional information on scan bodies. In addition, a dental model scanner was used to obtain reference data. The three-dimensional morphological, linear, and angular deviations between groups and reference data were analyzed using Geomagic Wrap 2021 software to compare trueness and precision.

Results: The extraoral scanning system demonstrated superior trueness in three-dimensional morphological, linear, and angular deviations compared with the intraoral scanning system, with statistically significant differences (P<0.001). The extraoral scanning system also showed a higher precision in three-dimensional morphological deviation (P<0.001). As the number of implants increased, the extraoral scanning system exhibited increased three-dimensional morphological and linear deviations (P<0.001) but maintained a stable angular deviation. The intraoral scanning system displayed significant increases in three-dimensional morphological, linear, and angular deviations with the increase in the number of implants (P<0.05).

Conclusions: The stereophotogrammetry-based extraoral scanning system outperforms intraoral scanning system in terms of the accuracy for multi-unit implant positioning and provides a novel approach for attaining a fully digital workflow for implant rehabilitation in edentulous jaws.

With the increasing demand for dental aesthetic outcomes, techniques for composite resin restoration intended for anterior teeth have been widely applied due to their minimally invasive and superior esthetic performance. Despite promising short-term outcomes, the long-term prognosis of anterior resin restorations remains challenging. Frequently reported complications include restoration fractures and decoloration. Material selection, operative procedures, and patient-related factors can affect the long-term outcomes of restorations. This review aims to systematically analyze the long-term clinical performance of resin restorations in anterior teeth. The key factors influencing treatment efficacy are also investigated. The findings are expected to provide a basis for optimizing clinical strategies in procedures for anterior composite resin restoration.

Objectives: This study aims to explore the potential relationships of cell-free DNA (cfDNA) in gingival crevicular fluid (GCF) with periodontal clinical indicators and the expression of DNA receptor pathway cyclic guanosine phosphate-adenosine phosphate synthase (cGAS)-stimulator of interferon genes (STING) in gingival tissues and human gingival fibroblasts (HGFs).

Methods: GCF and gingival tissue samples were collected from periodontally healthy individuals and patients diagnosed with periodontitis. Periodontal clinical indicators were recorded, including plaque index (PLT), bleeding index (BI), probing depth (PD), and clinical attachment level (CAL). The concentration of cfDNA in GCF was quantified, and the correlation between GCF and periodontal clinical indicators was analyzed. Immunofluorescence and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to assess the distribution of cGAS, STING, and p-STING in gingival tissues. Additionally, the mRNA expression levels of the key components of the cGAS-STING signaling pathway, namely, cGAS, STING, inhibitory of kappa-B kinase (IKK), nuclear factor kappa-B p65 (NF-κB p65), interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α), were measured. Furthermore, cfDNA extracted from GCF was employed to stimulate HGFs in the healthy control and periodontitis groups, and the mRNA expression levels of the key molecules of cGAS-STING signaling pathway were detected through Western blot and RT-qPCR.

Results: The concentration of cfDNA in GCF was found to be significantly elevated in the periodontitis group compared with the control group. Moreover, cfDNA concentration demonstrated a strong positive correlation with the periodontal clinical indicators. Immunofluorescence analysis revealed considerably increased percentage of fluorescence co-localization of cGAS, STING, and p-STING with the gingival fibroblast FSP-1 marker in the gingival tissues of the periodontitis group. The mRNA expression levels of cGAS, STING, IKK, NF-κB p65, IL-1β, IL-6,and TNF-α were significantly higher in the periodontitis group. In vitro stimulation of HGFs with GCF-derived cfDNA resulted in increased protein expression of cGAS and p-STING and considerably upregulated the mRNA expression levels of cGAS, STING, IKK, NF-κB p65, IL-1β, IL-6, and TNF-α in the healthy and periodontitis groups compared with the blank group. Correlation analysis showed that the concentration of cfDNA at the sampling site was positively correlated with the mRNA expression levels of cGAS, STING, NF-κB p65, and IL-6 in gingival tissues.

Conclusions: cfDNA concentrations in the GCF of patients with periodontitis are considerably elevated, and are associated with the activation of the cGAS-STING signaling pathway in HGFs. These findings suggest that cfDNA contributes to the progression of periodontitis.

Objectives: This study investigated the effects of a polycaprolactone (PCL)-polyethylene glycol (PEG) scaffold incorporated with concentrated growth factor (CGF) on the adhesion, proliferation, and osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs).

Methods: The PCL-PEG-CGF composite scaffold was fabricated using an immersion and freeze-drying technique. Its microstructure, mechanical properties, and biocompatibility were systematically characterized. The hPDLSCs were isolated through enzymatic digestion, and the hPDLSCs were identified through flow cytometry. Third-passage hPDLSCs were seeded onto the composite scaffolds, and their adhesion, proliferation and osteogenic differentiation were assessed using CCK-8 assays, 4',6-diamidino-2-phenylindole (DAPI) staining, alkaline phosphatase (ALP) staining, alizarin red staining, and Western blot analysis of osteogenesis-related proteins [Runt-related transcription factor 2 (Runx2), ALP, and morphogenetic protein 2 (BMP2)].

Results: Scanning electron microscopy revealed that the PCL-PEG-CGF composite scaffold exhibited a honeycomb-like structure with heterogeneous pore sizes. The composite scaffold exhibited excellent hydrophilicity, as evidenced by a contact angle (θ) approaching 0° within 6 s. Its elastic modulus was measured at (4.590 0±0.149 3) MPa, with comparable hydrophilicity, fracture tensile strength, and fracture elongation to PCL-PEG scaffold. The hPDLSCs exhibited significantly improved adhesion to the PCL-PEG-CGF composite scaffold compared with the PCL-PEG scaffold (P<0.01). Additionally, cell proliferation was markedly improved in all the experimental groups on days 3, 5, and 7 (P<0.01), and statistically significant differences were found between the PCL-PEG-CGF group and other groups (P<0.01). The PCL-PEG-CGF group showed significantly elevated ALP activity (P<0.05), increased mineralization nodule formation, and upregulated expression of osteogenic-related proteins (Runx2, BMP2 and ALP; P<0.05).

Conclusions: The PCL-PEG-CGF composite scaffold exhibited excellent mechanical properties and biocompatibility, enhancing the adhesion and proliferation of hPDLSCs and promoting their osteogenic differentiation by upregulating osteogenic-related proteins.

Artificial intelligence (AI) is rapidly advancing in periodontology, bringing new opportunities to clinical diagnosis, risk assessment, personalized treatment planning, and remote patient care. Leveraging core technologies such as deep learning, machine learning, and natural language processing, AI significantly enhances the sensitivity of early periodontal disease detection and provides precise quantification of alveolar bone loss and soft tissue damage. AI facilitates multimodal data integration by synthesizing medical history, lifestyle factors, and imaging data, thereby offering enhanced accurate risk prediction and personalized therapeutic recommendations. By integrating remote monitoring with tailored health counseling, AI helps patients maintain adherence to self-care protocols, significantly improving their oral health-related quality of life and treatment satisfaction. Moreover, AI demonstrates considerable potential in periodontal research and education, particularly in large-scale data mining, virtual clinical case simulations, and natural language processing-assisted literature management. Nevertheless, challenges remain concerning model generalizability, data quality, ethical concerns, and interpretability. The advancement of multi-center big-data platforms is expected to foster a profound integration of AI and periodontology, propelling precision medicine and digital healthcare, enabling holistic management from prevention to long-term care, and enhancing diagnostic efficiency and patient health outcomes.

Objectives: This study aims to investigate the impact of glutathione S-transferase (GST) on the environmental adaptability of Streptococcus mutans (S. mutans).

Methods: A GST knockout strain ΔgsT was constructed. Transcriptomic sequencing was performed to analyze the gene expression differences between the wild-type S. mutans UA159 and its GST knockout strain ΔgsT. Comprehensive functional assessments, including acid tolerance assays, hydrogen peroxide challenge assays, nutrient limitation growth assays, and fluorescence in situ hybridization, were conducted to evaluate the acid tolerance, antioxidant stress resistance, growth kinetics, and interspecies competitive ability of ΔgsT within plaque biofilms.

Results: Compared with the wild-type S. mutans, 198 genes in ΔgsT were significantly differentially expressed and enriched in pathways related to metabolism, stress response, and energy homeostasis. The survival rate of ΔgsT in acid tolerance assays was markedly reduced (P<0.01). After 15 min of hydrogen peroxide challenge, the survival rate of ΔgsT decreased to 38.12% (wild type, 71.75%). Under nutrient-limiting conditions, ΔgsT exhibited a significantly lower final OD₆₀₀ value than the wild-type strain (P<0.05). In the biofilm competition assays, the proportion of S. mutans ΔgsT in the mixed biofilm (8.50%) was significantly lower than that of the wild type (16.89%) (P<0.05).

Conclusions: GST enhances the acid resistance, oxidative stress tolerance, and nutrient adaptation of S. mutans by regulating metabolism-related and stress response-related genes.

Tooth resorption is the degradation of dental hard tissue due to the continuous action of odontoclasts. External cervical resorption refers to the cervical resorption of a tooth due to destruction and/or defects of the periodontal ligament or subepithelial cementum. In this paper, we report a case of maxillary central incisor with external cervical resorption after dental trauma and orthodontic treatment. The resorption site and morphology of the affected tooth were thoroughly analyzed by cone beam computed tomography prior to the operation. Dental operating microscope and layered external repair with composite resin and bioceramics ensured a perfect restoration of the resorption, and the vital pulp was preserved. The 6-year follow-up indicated a favorable treatment effect.

Foreign bodies in the tongue are rare in clinical practice. Accurate localization and appropriate surgical path selection are essential to reduce surgical risk and postoperative complications. This paper reports a case in which the fishbone foreign body at the base of tongue was removed using a translingual ventral approach aided with imaging localization.