[Systemic Influencing Factors of Dentition Defect in Type 2 Diabetes Mellitus Patients with Periodontitis].

Objective: To analyze the influencing factors of dentition defect in people with type 2 diabetes mellitus (T2DM) and periodontitis and to provide evidence-based support for improving the oral health and quality of life of T2DM patients. Methods: A total of 169 patients with T2DM and periodontitis were selected by convenience sampling. According to the number of remaining teeth, the subjects were divided into two groups, group A (number of remaining teeth in the mouth≥20, n=115) and group B (the number of remaining teeth in the mouth<20, n=54). Questionnaire surveys, systemic and oral examinations, and laboratory blood tests were performed. Systematic influencing factors of dentition defect in people with T2DM and periodontitis were analyzed with logistic regression. Results: Compared with patients in group A, patients in group B had higher findings in age, systolic blood pressure (SBP), prevalence of coronary heart disease and hyperlipidemia, glycosylated hemoglobin (HbA1c), periodontal probing depth (PD), and clinical attachment loss (CAL). Furthermore, their behaviors and awareness of oral health were not as good as those of patients in group A. Logistic regression showed that age, HbA1c, and SBP were independent risk factors for the number of remaining teeth in the mouth <20 among T2DM patients with periodontitis ( P<0.05). Conclusion: Increasing age, lower HbA1c, and increased SBP are the most important influencing factors for the number of remaining teeth in the mouth <20 in T2DM patients with periodontitis. Clinical practitioners should give more attention to the general health status of the patients and strengthen health education, thereby improving patients' quality.

[Salivary Peptide Profiling Analysis of Patients with Periodontitis and Chronic Obstructive Pulmonary Disease].

Objective: To analyze the salivary peptide profiles of patients with periodontitis (PD) and chronic obstructive pulmonary disease (COPD), to identify differentially expressed peptides that are associated with diseases, to explore for biomarkers with potential diagnostic significance, and to probe for new perspectives for the early prevention and treatment of COPD. Methods: A total of 10 PD patients (the PD group), 10 PD patients with COPD (the PD plus COPD group), and 8 healthy controls (the Control group) were selected for the study. The clinical data and saliva samples of the subjects were collected. Salivary supernatant samples were separated and purified with weak-cation-exchange magnetic bead-based (WCX-MB). With matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS), the biodata of the samples were obtained and differential salivary peptide profiling was conducted to screen for peptides exhibiting inter-group differences. In addition, all the differentially expressed peptides were examined and verified with liquid chromatography tandem mass spectrometry (LC-MS/MS). Result: An average of 77 peptide mass peaks were detected among three groups, the peaks intensities differed significantly for 10 peptides between PD patients and PD patients with COPD. Among them, eight peptides (1193.5, 1836.2, 1735.1, 1321.3, 1356.8, 2086.8, 1863.6, and 2230.9) showed increased expression and two peptides (1067.3 and 1124.4) showed decreased expression in the PD plus COPD group, in comparison with the PD group. Among the 10 differential peptides, 1193.5 and 1356.8 were identified as histidine-rich protein-1, submaxillary gland androgen-regulated protein 3B, and salivary acidic proline-rich protein 1/2. Conclusion: With WCX-MB and MALDI-TOF-MS, we have identified, from the saliva of patients with concomitant PD and COPD, differentially expressed salivary peptides that were associated with diseases. The differentially expressed peptides thus screened out show promises for being used as auxiliary biomarkers for early diagnosis of COPD.

Triggering receptor expressed on myeloid cells-2 stimulates osteoclast differentiation and bone loss in periodontitis.

OBJECTIVE: To investigate the expression of triggering receptor expressed on myeloid cells 2 (TREM-2) in the healthy and diseased tissue, including gingivitis or periodontitis, and then to assess whether it has an impact on the development of periodontitis. METHODS AND MATERIALS: The gingival tissues from healthy controls, gingivitis, and periodontitis underwent hematoxylin-eosin and immunohistochemical staining, and the association of TREM-2 expression or TREM-2+ cell counts with clinical parameters was assessed. An anti-TREM-2 antibody was used to block the osteoclastogenesis in vitro and during the experimental periodontitis by injection into the gingiva. The relative gene expression of TREM-2 in different gingival tissues was analyzed by quantitative PCR. RESULTS: In the gingival tissues of periodontitis, TREM-2 expression and TREM-2+ cell counts were significantly higher than those of gingivitis and healthy controls (p<0.05). In the group of periodontitis showing moderate signs, the gingival tissues displayed significantly lower TREM-2 expression, in contrast with the group with advanced periodontal symptoms (p < 0.05). Consistently, blocking TREM-2 significantly decreased osteoclast formation both in vitro and in vivo (p < 0.05). CONCLUSION: Increased TREM-2 expression and TREM-2+ cells were positively associated with the development of periodontitis. Osteoclast differentiation and stimulating alveolar bone loss were partly relied on TREM-2, which could be a target to be blocked for attenuating osteoclastogenesis in periodontitits.

Differential immune cell infiltrations between healthy periodontal and chronic periodontitis tissues.

BACKGROUND: Host immunity plays an important role against oral microorganisms in periodontitis. METHODS: This study assessed the infiltrating immune cell subtypes in 133 healthy periodontal and 210 chronic periodontitis tissues from Gene Expression Omnibus (GEO) datasets using the CIBERSORT gene signature files. RESULTS: Plasma cells, naive B cells and neutrophils were all elevated in periodontitis tissues, when compared to those in healthy controls. In contrast, memory B cells, resting dendritic, mast cells and CD4 memory cells, as well as activated mast cells, M1 and M2 macrophages, and follicular helper T cells, were mainly present in healthy periodontal tissues. Furthermore, these periodontitis tissues generally contained a higher proportion of activated CD4 memory T cells, while the other subtypes of T cells, including resting CD4 memory T cells, CD8 T cells, follicular helper T cells (TFH) and regulatory T cells (Tregs), were relatively lower in periodontitis tissues, when compared to healthy tissues. The ratio of dendritic and mast cells and macrophages was lower in periodontitis tissues, when compared to healthy tissues. In addition, there was a significant negative association of plasma cells with most of the other immune cells, such as plasma cells vs. memory B cells (γ = - 0.84), plasma cells vs. resting dendritic cells (γ = - 0.64), plasma cells vs. resting CD4 memory T cells (γ = 0.50), plasma cells versus activated dendritic cells (γ = - 0.46), plasma cells versus TFH (γ = - 0.46), plasma cells versus macrophage M2 cells (γ = - 0.43), or plasma cells versus macrophage M1 cells (γ = - 0.40), between healthy control and periodontitis tissues. CONCLUSION: Plasma cells, naive B cells and neutrophils were all elevated in periodontitis tissues. The infiltration of different immune cell subtypes in the periodontitis site could lead the host immunity against periodontitis.

S100A4 upregulation suppresses tissue ossification and enhances matrix degradation in experimental periodontitis models.

AIM: S100A4, also known as fibroblast-specific protein 1 or metastasin 1, is not only highly expressed in growth-stimulated cultured cells and metastatic tumor cells, but also in the periodontal ligament. The aim of this study was to investigate the roles of S100A4 in the pathogenesis of periodontitis and its regulatory mechanisms in inflammatory milieu. METHODS: Experimental periodontitis was induced in rats by submarginal silk ligatures. TRAP activity and S100A4 expression in periodontal ligaments were examined using immunohistochemistry and immunofluorescence methods. IL-1ß-treated human periodontal ligament cells (hPDLCs) were used as in vitro model of experimental periodontitis. S100A4 mRNA and protein were assessed using qRT-PCR and Western blot, respectively. hPDLCs were transfected with either S100A4 overexpression plasmids or shRNAs plasmids. The mineralization in hPDLCs was evaluated with a 12-d osteogenic induction assay, and the expression of ALP, OCN, MMP-2 and MMP-13 was analyzed by qRT-PCR. RESULTS: In the periodontal ligaments of rats with experimental periodontitis, TRAP activity and S100A4 protein staining were considerably more intense compared with those in the control rats. Treatment of hPDLCs with IL-1ß (10, 50 and 100 ng/mL) dose-dependently increased the mRNA and protein levels of S100A4. Transfection with shRNAs markedly increased mineralized nodule formation and the osteogenic-related markers ALP and OCN levels in hPDLCs, whereas the overexpression of S100A4 significantly reduced mineralized nodule formation, and increased the matrix degradation enzymes MMP-2 and MMP-13 levels in hPDLCs. CONCLUSION: S100A4 is upregulated in the experimental rat periodontitis and in IL-1ß-treated hPDLCs, where S100A4 suppresses osteogenic differentiation and enhances matrix degradation. Thus, S100A4 is a potential target for the treatment of periodontitis.

Comparison of tissue-engineered bone from different stem cell sources for maxillary sinus floor augmentation: a study in a canine model.

PURPOSE: To compare the potential of tissue-engineered bone derived from different stem cell sources for canine maxillary sinus augmentation. MATERIALS AND METHODS: Bilateral maxillary sinus floor augmentations were performed in 6 beagles and were randomly repaired with 3 graft types: Bio-Oss granules alone (n = 4; group A), a complex of osteoblasts derived from bone marrow mesenchymal stem cells (BMMSCs) and Bio-Oss (n = 4; group B), and a complex of osteoblasts derived from periodontal ligament stem cells (PDLSCs) and Bio-Oss (n = 4; group C). After 12 weeks, fluorescent labeling, maxillofacial computed tomography, scanning electron microscopy, and histologic and histomorphometric analyses were used to evaluate new bone deposition, mineralization, and remodeling in the augmented area. RESULTS: The osteogenic capacity was greater in groups B and C than in group A. The level tended to be higher in group C than in group B; however, the difference was not statistically significant. CONCLUSIONS: Seeding of PDLSCs or BMMSCs onto Bio-Oss can promote bone formation and mineralization and maintain the maximum volume of the augmented maxillary sinus. These tissue-engineered bone complexes might be a good option for augmentation of the maxillary sinus in edentulous patients.

Clinical application of robots in dentistry: A scoping review.

PURPOSE: The surge in digitalization and artificial intelligence has led to the wide application of robots in various fields, but their application in dentistry started relatively late. This scoping review aimed to comprehensively explore and map the current status of the clinical application of robots in dentistry. STUDY SELECTION: An iterative approach was used to gather as much evidence as possible from four online databases, including PubMed, the China National Knowledge Infrastructure, the Japan Science and Technology Information Aggregator, Electronic, and the Institute of Electrical and Electronics Engineers, from January 1980 to December 2022. RESULTS: A total of 113 eligible articles were selected from the search results, and it was found that most of the robots were developed and applied in the United States (n = 56; 50%). Robots were clinically applied in oral and maxillofacial surgery, oral implantology, prosthodontics, orthodontics, endodontics, and oral medicine. The development of robots in oral and maxillofacial surgery and oral implantology is relatively fast and comprehensive. About 51% (n = 58) of the systems had reached clinical application, while 49% (n = 55) were at the pre-clinical stage. Most of these are hard robots (90%; n = 103), and their invention and development were mainly focused on university research groups with long research periods and diverse components. CONCLUSIONS: There are still limitations and gaps between research and application in dental robots. While robotics is threatening to replace clinical decision-making, combining it with dentistry to gain maximum benefit remains a challenge for the future.

Amorphous Precursor-Mediated Calcium Phosphate Coatings with Tunable Microstructures for Customized Bone Implants.

Calcium phosphate (CaP) is frequently used as coating for bone implants to promote osseointegration. However, commercial CaP coatings via plasma spraying display similar microstructures, and thus fail to provide specific implants according to different surgical conditions or skeletal bone sites. Herein, inspired by the formation of natural biominerals with various morphologies mediated by amorphous precursors, CaP coatings with tunable microstructures mediated by an amorphous metastable phase are fabricated. The microstructures of the coatings are precisely controlled by both polyaspartic acid and Mg2+ . The cell biological behaviors, including alkaline phosphatase activity, mineralization, and osteogenesis-related genes expression, on the CaP coatings with different microstructures, exhibit significant differences. Furthermore, in vivo experiments demonstrate the osseointegration in different types of rats and bones indeed favors different CaP coatings. This biomimetic strategy can be used to fabricate customized bone implants that can meet the specific requirements of various surgery conditions.

Tilted implantation technique for edentulous patients.

The tilted implantation technique is characterized by placing the implant at an angle of more than 15° and less than 45° from the horizontal plane. This technique can avoid damaging the maxillary sinus, inferior alveolar nerve, nasal base, and other anatomical structures when the height of the upper and lower jaw available bone is insufficient, to maximize the use of available bone and avoid a large range of bone increment. The tilted implantation technique can reduce the trauma of the surgery, increase the possibility of immediate restoration and shorten the treatment cycle, which has been widely used clinically. In this review, the scope of application, design elements, design scheme and complications of the tilted implantation technique for edentulous patients will be described.

Multilevel factor analysis of flipped classroom in dental education: A 3-year randomized controlled trial.

PURPOSE: Previous studies have rarely attempted to test the confounding factors that may affect learning outcomes of the flipped classroom. The purpose of this study was to assess how flipped classrooms affect the acquisition of knowledge in clinical dental education based on multilevel factor analysis. METHOD: The authors conducted a 3-year (2017, 2018, and 2019) randomized controlled trial in a series of introductory prosthodontics courses in dental education. A total of 137 participants were randomly assigned to flipped classroom (n = 70, 51%) or lecture (n = 67, 49%) formats. The flipped group was instructed to self-learn knowledge-based content through online preparation materials, including videos and text, while the lecture group was given text only. Both groups were provided with the same study content and opportunities for different styles of learning. The session attendance rate and number of times the materials were accessed were monitored. Individual and team readiness assurance tests (IRAT/TRAT) were conducted to evaluate knowledge acquisition. A multilevel linear regression analysis was conducted on both instructional styles (flipped vs. lecture) as an intervention factor, and confounding factors that could affect the outcomes were implemented. RESULTS: The average number of online accesses was 2.5 times per session in the flipped group and 1.2 in the lecture group, with a significant difference (p < .05). The average IRAT score was significantly higher in the flipped than in the lecture group (effect size [ES] 0.58, p < .001). The number of online accesses was significantly and positively correlated with IRAT scores (0.6 [0.4, 0.8]). The instructional style was significantly and positively correlated with TRAT scores (coefficient [95% confidence interval]: 4.6 [2.0, 7.3]), but it was not correlated with IRAT (4.3 [-0.45, 9.0]). CONCLUSIONS: The flipped classroom was more effective than the lecture format regarding knowledge acquisition; however, the decisive factor was not the instructional style but the number of individual learning occasions. The employment of the flipped classroom was the decisive factor for team-based learning outcomes.

Can overconfidence be debiased by low-probability/high-consequence events?

During the first half of 2008, China suffered three natural disasters: a heavy snow storm, an outbreak of hand-foot-mouth disease, and a severe earthquake. The aim of the present study is to explore how low-probability/high-consequence events influence overconfidence. In Study 1, opportunity samples were obtained by recruiting residents in three different types of disaster-hit areas to answer a peer-comparison probability judgment questionnaire about 1 month after the corresponding disaster occurred. The performance of 539 participants in disaster-hit areas was compared with that of 142 residents in a nondisaster area. The findings indicate that residents in disaster-hit areas were less overconfident than those in the nondisaster area on both positive and negative events. In Study 2, we surveyed a total of 336 quake-victims 4 and 11 months after the earthquake to examine whether the impact of disasters on overconfidence would decay with time. The resulting data indicate that the disaster victims became more overconfident as time elapsed. The overall findings suggest that low-probability/high-consequence events could make people less overconfident and more rational and seem to serve as a function of debiasing.

Spatial and seasonal variability of nitrous oxide in a large freshwater lake in the lower reaches of the Yangtze River, China.

Aquatic ecosystems are recognized as a source of N2O in accordance with the flux estimations of rivers and estuaries; however, limited research has been conducted on large lakes. In this study, we report the annual N2O dynamics of a large eutrophic freshwater lake located in the subtropical zone of East China. The dissolved N2O concentrations in Lake Chaohu were observed to be between 8.5 and 92.3 nmol L-1 with emission rates between 0.3 and 53.6 µmol m-2 d-1, exhibiting considerable spatiotemporal variability. The average seasonal N2O concentrations were obtained, with the highest value of 23.4 nmol L-1 found in winter and the lowest value of 12.7 nmol L-1 found in summer. In contrast to the N2O concentrations observed, the highest N2O emission rates occurred during summer, while the lowest emission rates occurred in autumn. The emissions of N2O were substantially high in the western part of the lake, which suffers from serious eutrophication. In addition, the hotspots of N2O emissions have been found around the inflowing mouth of the Nanfei River, which transports large amounts of nutrients into the lake. The results suggest that anthropogenically enhanced nutrient inputs may have a significant role in the production and emission of N2O. However, the negative relationship between the surface water temperature and the N2O concentration suggests that, N2O fluxes might be influenced by other inconspicuous mechanisms. In the future the nitrogen dynamics of water and sediment in the lake should be collated to reveal mechanisms controlling N2O emissions. In summary, Lake Chaohu acts as a source of N2O with its most eutrophic part contributing 54.9% of the total N2O emissions of the whole lake.

[Criteria for success in dental implants].

With the comprehensive application and development of implant dentistry in recent years, multi-institutional data have supported a large number of clinical research findings. A consensus was gradually reached on the evaluation of the state and effect of implants and types of indicators that were selected after restoration. This study aims to examine the frequently used criteria to define treatment success in implant dentistry.

Vitamin D reduces the serum levels of inflammatory cytokines in rat models of periodontitis and chronic obstructive pulmonary disease.

The purpose of this study was to investigate the effects of vitamin D in rat models of chronic obstructive pulmonary disease (COPD) and periodontitis. Animals with both periodontitis and COPD, or with periodontitis only, were established. Once the animal model was established, experimental groups received intraperitoneal injections of 25-hydroxyvitamin D3 (25-OHD3) for 8 weeks, while control groups received refined peanut oil. After sacrifice, inflammatory status was examined in terms of the serum levels of receptor activator of the nuclear factor κB ligand (RANKL), tumor necrosis factor alpha (TNF-α) and interleukins (IL-1 and IL-10), as well as alveolar bone loss, forced expiratory volume (0.20) (FEV 0.20), and the ratio of FEV0.2 to forced vital capacity. The results showed that 25-OHD3 treatment significantly alleviated inflammation by decreasing the serum levels of RANKL, TNF-α and IL-1 and increasing that of IL-10, while reducing alveolar bone loss and slightly improving lung function. These findings suggest that vitamin D supplementation could be a new clinical approach for the treatment of COPD and periodontitis.

BM-MSCs and Bio-Oss complexes enhanced new bone formation during maxillary sinus floor augmentation by promoting differentiation of BM-MSCs.

Bone marrow-derived mesenchymal stem cells (BM-MSCs) have been recognized as a new strategy for maxillary sinus floor elevation. However, little is known concerning the effect of the biomechanical pressure (i.e., sinus pressure, masticatory pressure, and respiration) on the differentiation of BM-MSCs and the formation of new bone during maxillary sinus floor elevation. The differentiation of BM-MSCs into osteoblasts was examined in vitro under cyclic compressive pressure using the Flexcell® pressure system, and by immunohistochemical analysis, qRT-PCR, and Western blot. Micro-CT was used to detect bone formation and allow image reconstruction of the entire maxillary sinus floor elevation area. Differentiation of BM-MSCs into osteoblasts was significantly increased under cyclic compressive pressure. The formation of new bone was enhanced after implantation of the pressured complex of BM-MSCs and Bio-Oss during maxillary sinus floor elevation. The pressured complex of BM-MSCs and Bio-Oss promoted new bone formation and maturation in the rabbit maxillary sinus. Stem cell therapy combined with this tissue engineering technique could be effectively used in maxillary sinus elevation and bone regeneration.

Effects of Ginkgo biloba extract on periodontal pathogens and its clinical efficacy as adjuvant treatment.

OBJECTIVE: To determine the effects of Ginkgo biloba extract (EGB) on major periodontal pathogens in subgingival plaque. METHODS: Sixty patients with moderate to severe periodontitis were selected and randomly assigned to 3 groups: EGB group, a positive (periocline) and a negative control groups. Subgingival plaque samples were collected before treatment and 1 week, 2 months and 4 months after treatment. The detection rates of 4 major periodontal pathogens-Treponema denticola (Td), Tannerella forsythus (Tf), Prevotella intermedia (Pi), and Porphyromonas gingivalis (Pg)-were detected by polymerase chain reaction (PCR). Clinical indicators were examined before treatment, 3 and 6 months after treatment. RESULTS: EGB significantly decreased the detection rate of all the 4 pathogens 1 week after treatment, and then gradually increased at 2 and 4 months. EGB's inhibition effect was better than or comparable to periocline, except for Pg in short-term. The difference of plaque index (PLI) and bleeding index (BI) was not statistically significant among the groups, while for probing depth (PD) and attachment loss (AL), the difference was statistically significant between the EGB group and negative control group at 3 and 6 months after treatment. CONCLUSION: EGB significantly inhibited major periodontal pathogens and can be used as an adjuvant for periodontitis treatment.

[Establishment of chronic periodontitis and chronic obstructive pulmonary disease model in SD rat].

OBJECTIVE: To establish a model of chronic periodontitis (CP) accompanied with chronic obstructive pulmonary disease (COPD) in SD rats and investigate the relationship between chronic periodontitis and COPD. METHODS: Equal gender SD rats were randomly divided into 4 groups, A: control group, B: CP group, C: COPD group, D: COPD with CP group (n = 10, respectively). Each group was subjected to its predesigned intervention to establish a specific disease model. After 10 weeks, animals were sacrificed. The level of alveolar bone loss, lung function measurement, and the histopathological changes of periodontal and lung tissues were examined. The serum tumor necrosis factor (TNF)-α level was detected by enzyme-linked immunoabsorbent assay kits. RESULTS: Bleeding index (BI) levels of group A and C were (0.25 ± 0.04) and (1.30 ± 0.25), respectively. Attachment loss was (0.43 ± 0.02) and (0.51 ± 0.02) mm. BI levels in group B and D were significantly higher than those in group A and C. Forced expiratory volume in 0.2 second to forced vital capital ratio (FEV(0.2)/FVC) values in group B, C and D were significantly lower than that in group A. Pulmonary function were worse in group D than that in group C (P < 0.05). The levels of serum TNF-α, a sensitive indicator of both diseases, were increased in all test groups compared with the control, and increased most in group D. CONCLUSIONS: The chronic periodontitis and chronic obstructive pulmonary disease model was established in SD rat. The chronic periodontitis may be a risk factor for promoting and inducing COPD.

Expression, localisation and synthesis of versican by the enamel organ of developing mouse molar tooth germ: an in vivo and in vitro study.

OBJECTIVE: Versican is a large, aggregating chondroitin sulphate proteoglycan. In dental tissue, versican expression occurs primarily in mesenchymal tissue but rarely in epithelial tissue. We investigated the expression, localisation and synthesis of versican in the enamel organ of the developing tooth germ. DESIGN: To elucidate versican localisation in vivo, in situ hybridisation and immunohistochemistry were conducted in foetal ICR mice at E11.5-E18.5. Epithelium and mesenchyme from the lower first molars at E16.0 were enzymatically separated and versican mRNA expression was investigated by semi-quantitative RT-PCR. Organ culture of the separated samples combined with metabolic labelling with [(35)S], followed by gel filtration, was performed to analyse secreted proteoglycans. RESULTS: Versican mRNA was first expressed in the thickened dental epithelium at E12.0 and continued to be expressed in the enamel organ until the bell stage. Versican immunostaining was detected in the stellate reticulum areas from the bud stage to the apposition stage. The enamel organ at E16.0 expressed versican mRNA at a level comparable to that in dental mesenchyme. Furthermore, when compared to dental mesenchyme, about 1/2-3/4 of the [(35)S]-labelled versican-like large proteoglycan was synthesised and released into tissue explants by the enamel organ. CONCLUSIONS: The dental epithelium of developing tooth germ is able to synthesise significant amounts of versican.

[Analysis on oral health care utilization and expenditure of residents in Beijing].

OBJECTIVE: To analyze the dental care utilization and expenditure of residents in Beijing, and to provide some basis on the policy of oral health insurance system. METHODS: A cross-sectional survey was conducted among 1,517 subjects (urban area) and 1,878 subjects (rural area) of all age groups in Beijing selected by stratified, clustering, random sampling. The data of oral health care utilization and expenditure were collected in their home. RESULTS: The number of the people who visited a dentist in a year were low both in urban area and in rural area, but the expenditure for oral health care per visit were quite high. The value of utilization of dental care in rural residents was 1/3 of that in urban residents, while the value of expenditure in rural people was about 1/2 of that in urban people. 2.07% incomes of rural residents were used for dental care per year, the corresponding value of urban residents was 1.77%. There was significant difference on the expenditure among those with different demographic, socio-economic backgrounds. CONCLUSIONS: The expenditure for oral health care was high in Beijing, which accounted for quite a lot in average incomes per year. The burden of expenditure for dental care on rural residents was heavier than that on urban residents. The level of expenditure for dental care could provide some references for oral health insurance system in Beijing.