Accuracy and efficiency of dynamic navigated root-end resection in endodontic surgery: a pilot in vitro study.

BACKGROUND: The operation accuracy and efficiency of dynamic navigated endodontic surgery were evaluated through in vitro experiments. This study provides a reference for future clinical application of dynamic navigation systems in endodontic surgery. MATERIALS AND METHODS: 3D-printed maxillary anterior teeth were used in the preparation of models for endodontic surgery. Endodontic surgery was performed with and without dynamic navigation by an operator who was proficient in dynamic navigation technology but had no experience in endodontic surgery. Optical scanning data were applied to evaluate the length and angle deviations of root-end resection. And the operation time was recorded. T tests were used to analyze the effect of dynamic navigation technology on the accuracy and duration of endodontic surgery. RESULTS: With dynamic navigation, the root-end resection length deviation was 0.46 ± 0.06 mm, the angle deviation was 2.45 ± 0.96°, and the operation time was 187 ± 22.97 s. Without dynamic navigation, the root-end resection length deviation was 1.20 ± 0.92 mm, the angle deviation was 16.20 ± 9.59°, and the operation time was 247 ± 61.47 s. Less deviation was achieved and less operation time was spent with than without dynamic navigation (P < 0.01). CONCLUSION: The application of a dynamic navigation system in endodontic surgery can improve the accuracy and efficiency significantly for operators without surgical experience and reduce the operation time.

Clinical Outcome and Predictors of Endodontic Microsurgery Using Cone-beam Computed Tomography: A Retrospective Cohort Study.

INTRODUCTION: The aim of this retrospective cohort study was to evaluate the clinical outcomes and identify the prognostic factors of endodontic microsurgery based on cone-beam computed tomographic (CBCT) scans. METHODS: Patients who underwent endodontic microsurgery in teeth with asymptomatic apical periodontitis were included. The clinical outcomes were determined based on clinical and radiographic examinations after surgery 12-48 months. Radiographic healing was assessed on CBCT images by using the modified PENN 3-dimensional criteria and classified into 4 categories: complete, limited, uncertain, and unsatisfactory healing. Multivariate logistic regression was performed to detect outcome risk factors. RESULTS: Of the 204 teeth in 173 invited patients, 148 teeth of 126 patients were examined at review. On CBCT images, 88 teeth (59.5%) showed complete healing, and 42 (28.4%) teeth showed limited healing. All these 130 teeth were asymptomatic and achieved a clinical success rate of 87.8%. Uncertain healing was observed in 9 teeth, one of which was symptomatic. The remaining 9 teeth were unsatisfactory healing on CBCT scans, including 6 teeth with clinical symptoms and 3 free. Lesion type and root-end filling quality were significant outcome predictors (P < .05). The risk of treatment failure for teeth with combined endodontic-periodontal lesions was 8.6 times higher than that for teeth with isolated endodontic lesions. Adequate root-end filling quality improved the probability of success by 5.3 times. CONCLUSIONS: Based on CBCT data, an adequate performed endodontic microsurgery could have predictable success in teeth without periodontal involvement.

[Preparation of triptolide-loaded dissolving microneedles and its transdermal penetration].

Triptolide(TP), the main active and toxic component of Tripterygium wilfordii, has the limitations of low bioavailability, poor absorption, low concentration in plasma, and small lethal dose. Microneedle(MN), the hybrid of hypodermic needle and transdermal patch, is a physical penetration-enhancing system. Dissolving microneedles(DMNs) can be tailored to specific needs of degradation rate. In this study, the TP-loaded DMNs(DMNs-TP) were prepared with the two-step centrifugation method. The optimal ratio of PVA to PVP K30, water content in matrix solution, demoulding method, and plasticizer for preparing DMNs were investigated with the indexes of formability and mechanical strength. The drug loading capacity was determined by HPLC and morphological characteristics were observed under an optical microscope. The mechanical properties were investigated by H&E staining and Franz diffusion cell was used to detect the in vitro skin permeation characteristics. Through the experiment, we confirmed that the optimal backing material should be PVA and PVP K30(3∶1) and the optimal ratio of matrix material to water should be 3∶4. The prepared DMNs-TP were pyramidal with smooth surface and length of approximately 550 µm. Each patch(2.75 cm~2) had the drug loading capacity of(153.41±2.29) µg, and TP was located in the upper part of the needle. The results of in vitro skin permeation assay demonstrated that the cumulative penetration of TP in DMNs-TP reached 80% in 24 h, while little TP solution penetrated the skin, which proved that DMNs promoted the transdermal delivery of TP.

Accuracy of root-end resection using a digital guide in endodontic surgery: An in vitro study.

BACKGROUND/PURPOSE: It is difficult to achieve accurate root-end resection clinically. This in vitro study was conducted to evaluate the operation accuracy of a digital endodontic surgical guide. MATERIALS AND METHODS: 56 extracted maxillary anterior teeth were prepared for endodontic surgical models. The models were randomly divided into 4 groups equally according to the guide (with guide/no guide) and the operator (experienced/inexperienced). Endodontic microsurgeries were performed on models in each group. The deviations in length and angle of the root-end resection were measured based on the optical scanning data of the pre- and postoperative teeth. The general linear model was performed to analyze the effect of a guide on root-end resection deviation. RESULTS: Using a guide, the mean length deviation for experienced/inexperienced operators reduced from 0.99 mm (95% CI [confidence interval, CI], 0.66-1.33 mm)/1.18 mm (95% CI, 0.50-1.86 mm) to 0.31 mm (95% CI, 0.20-0.42 mm)/0.31 mm (95% CI, 0.24-0.37 mm). The mean angle deviation for experienced/inexperienced operators reduced from 16.74° (95% CI, 10.61-22.86°)/15.06° (95% CI, 9.19-20.94°) to 5.04° (95% CI, 3.31-6.77°)/6.79° (95% CI, 4.91-8.67°). The difference was significant between procedures performed with and without a guide (P < 0.01). CONCLUSION: Application of the digital guide in vitro endodontic surgery could improve the accuracy of root-end resection.

A six-herb Chinese medicine composition ointment as a promising candidate for treatment of hypertrophic scars.

Objective: To study the anti-hypertrophic scar effect of the six-herb Chinese medicine composition (SCMC) ointment on the rabbit ear hypertrophic scar models. Methods: The optimal formulation of SCMC ointment matrix was screened by the orthogonal designs and a series of evaluation tests. The SCMC ointment was prepared through emulsifying method. The rabbit ear hypertrophic scar models were established and used to investigate the anti-hypertrophic scar effect of SCMC ointment. Results: Our results demonstrated that all the quality control indications of the SCMC ointment met the requirements. Anti-hypertrophic scar activity results showed that all the rabbit ear scar tissues appeared different degrees of shrink and fading, and took an unobvious but palpable shift from hard to soft texture with the low, middle and high concentration SCMC ointments treatments in vivo. Additionally, on 21st day the scar area and thickness in different concentrations of SCMC ointment groups were significantly reduced than control group, in a concentration-dependent manner. The immunohistochemical results also indicated that the SCMC ointment had good anti-hypertrophic scar properties and could inhibit hypertrophic scar formation. Conclusion: The SCMC ointment could improve the blood circulation condition of hypertrophic scar tissues. Our research has demonstrated the Chinese medicine composition ointment with good anti-hypertrophic scar properties that could be used to treat hypertrophic scars. Meanwhile, it provides a theoretical basis for further clinical application.

Root Canal Morphology of Mandibular Incisors with Double Root Canals in a Chinese Population.

OBJECTIVE: To investigate the bilateral symmetry of double root canals, variation in root canal bifurcation and position of canal orifices in mandibular incisors in a Chinese population. METHODS: A total of 149 subjects with mandibular incisors with two canals were selected from 866 patients based on CBCT images and divided into three groups: group 1 (< 21 years), group 2 (21-40 years) and group 3 (> 40 years). The prevalence of bilateral symmetry of double root canals (type III and type V), the distance between the cementoenamel junction (CEJ) and the bifurcation (D1) and the distance between the two canal orifices (D2) were calculated and analysed. RESULTS: The bilateral symmetry of type III for mandibular central incisors (MCIs) (44.4%) was significantly lower than that for mandibular lateral incisors (MLIs) (63.4%). D1 was greater in group 1 (4.63 ± 1.35mm) than in group 2 (3.99 ± 1.02 mm) and group 3 (3.90 ± 1.95 mm). D2 was shorter in in MCIs (0.65 ± 0.20 mm) than in MLIs (0.74 ± 0.22 mm). CONCLUSION: Special attention is required in the root canal treatment of mandibular incisors, especially in patients aged above 21 years.

Is Intentional Replantation Appropriate for Treatment of Extensive Endodontic-periodontal Lesions Related to Palatogingival Groove?

This report describes the cases of two patients with a maxillary lateral incisor with palatogingival groove and extensive endodontic-periodontal lesions. Although it is reported that acceptable periodontal status is of great importance in case selection in intentional replantation, it is suggested in this report that intentional replantation could be chosen instead of immediate extraction if extensive endodontic-periodontal lesions exist in a tooth with palatogingival groove. The gingival margin position and gingival papilla were well preserved and the bone defect was almost completely repaired. This was beneficial to the aesthetic prosthodontic treatment and implantation, although external root resorption was observed.

[Screening and phosphate-solubilizing characteristics of phosphate-solubilizing actinomycetes in rhizosphere of tree peony.] / ç‰¡ä¸¹æ ¹é™ æº¶ç£·æ”¾çº¿èŒçš„ç­›é€‰åŠå ¶æº¶ç£·ç‰¹æ€§.

A strain PSPSA1 with strong phosphate-solubilizing ability was isolated from the rhi-zosphere of tree peony. This strain was identified based on morphological characteristics, physiological and biochemical experiments, and 16S rDNA sequence analysis. Furthermore, its genetic stabi-lity and phosphate-solubilizing characteristics were investigated. Strain PSPSA1 was identified as the actinomycete Streptomyces albireticuli and showed high genetic stability. The order of phosphate solubilization capacity (PSC) in different phosphorus-source culture media was calcium phosphate (158.5 mg·L-1) > aluminum phosphate (139.9 mg·L-1) > ferric phosphate (127.7 mg·L-1) > lecithin (45.6 mg·L-1). The PSC and pH were significantly negatively correlated in inorganic phosphorus solution, but were not correlated in organic phosphorus solution. When using different carbon sources, PSC was in the order of lactose > glucose > maltose > fructose > sucrose > starch > cellulose. For different nitrogen sources, PSC was in the order of peptone > ammonium nitrate > ammonium sulfate > potassium nitrate > urea. Using glucose as a carbon source and peptone as a nitrogen source, strain PSPSA1 achieved the highest PSC of 202.6 mg·L-1. After incubated for 60 days, the available phosphorus content in soil with a single application of strain PSPSA1 increased by 68.2% compared with control, and the available phosphorus content in soil with mixed application of strain PSPSA1 and organic fertilizer increased by 76.7% compared with a single application of organic fertilizer. The results indicated that the strain PSPSA1 had a strong ability to dissolve insoluble phosphorus and its mixed application with organic fertilizer improved the phosphorus solubilization. Thus, PSPSA1 is a promising microbial resource for the production of high-efficiency biological phosphorus fertilizer.

Comparison of efficacy and outcome satisfaction between in-office and home teeth bleaching in Chinese patients.

This in vivo study aimed to evaluate the efficacy of in-office and home teeth bleaching in Asian patients. Moreover, the correlation between tooth color change and patient's outcome satisfaction was investigated. Overall, 40 Chinese patients were randomly divided into two groups and prescribed in-office (OB) or take-home bleaching (HB). The color of the maxillary central incisor and canine were recorded at baseline, immediately after first treatment, 1 week, and 3 months after treatment by using a spectrophotometer. Bleaching sensitivity and outcome satisfaction were assessed using Likert and visual analogue scale (VAS), and the results were analyzed using independent t-test and Pearson correlation (P < 0.05). ΔL*, Δa*, Δb*, and ΔE* values of HB were greater than those of OB. Color changes observed in canines were generally greater than those in incisors. Moreover, HB was generally associated with less tooth sensitivity than OB. Patients were satisfied with both treatments, but VAS scores were greater for HB. Furthermore, the correlation between ΔE* and VAS was significant for canines immediately after the first treatment and 1 week after HB. In conclusion, HB was more effective in lightening teeth and reducing chromacity in Chinese patients. The correlation between tooth color change and outcome satisfaction was generally insignificant and weak.

T2-Weighted Magnetic Resonance Imaging of Hepatic Tumor Guided by SPIO-Loaded Nanostructured Lipid Carriers and Ferritin Reporter Genes.

Nowadays, there is a high demand for supersensitive contrast agents for the early diagnostics of hepatocarcinoma. It has been recognized that accurate imaging information is able to be achieved by constructing hepatic tumor specific targeting probes, though it still faces challenges. Here, a AGKGTPSLETTP peptide (A54)-functionalized superparamagnetic iron oxide (SPIO)-loaded nanostructured lipid carrier (A54-SNLC), which can be specifically uptaken by hepatoma carcinoma cell (Bel-7402) and exhibited ultralow imaging signal intensity with varied Fe concentration on T2-weighted imaging (T2WI), was first prepared as an effective gene carrier. Then, an endogenous ferritin reporter gene for magnetic resonance imaging (MRI) with tumor-specific promoter (AFP-promoter) was designed, which can also exhibit a decrease in signal intensity on T2WI. At last, using protamine as a cationic mediator, novel ternary nanoparticle of A54-SNLC/protamine/DNA (A54-SNPD) as an active dual-target T2-weighted MRI contrast agent for imaging hepatic tumor was achieved. Owing to the synergistic effect of A54-SNLC and AFP-promoted DNA targeting with Bel-7402 cells, T2 imaging intensity values of hepatic tumors were successfully decreased via the T2 contrast enhancement of ternary nanoparticles. It is emphasized that the novel A54-SNPD ternary nanoparticle as active dual-target T2-weighted MRI contrast agent were able to greatly increase the diagnostic sensitivity and specificity of hepatic cancer.

Outcomes of Endodontic Microsurgery Using a Microscope and Mineral Trioxide Aggregate: A Prospective Cohort Study.

INTRODUCTION: The aim of this study was to investigate the outcome of endodontic microsurgery and analyze the prognostic factors. METHODS: Our prospective cohort study included 98 teeth in 81 patients. An endodontist performed all surgical procedures using endodontic microsurgical approaches. The treated teeth were recalled and examined clinically and radiographically at least 1 year after surgical treatment. The outcome was determined based on clinical and radiographic results. Radiographic healing was classified into 4 categories: complete, incomplete, uncertain, and unsatisfactory healing. An analysis of predictors was performed using multivariate logistic regression. RESULTS: At recall, 74 of the 98 teeth (75.5%) were examined 12 to 30 months after surgery; 71 of the 74 teeth were analyzed clinically and radiographically, and 3 teeth had been extracted. On periapical radiographs, 55 (74.3%) of the 74 teeth showed complete healing, whereas 12 (16.2%) demonstrated incomplete healing. Together the percentage of complete and incomplete healing was 90.5% (67/74), and all 67 teeth were clinically normal. Uncertain healing was observed in 3 teeth (4.1%), one of which was symptomatic with swelling and sinus tract involvement and the other 2 were asymptomatic. The remaining 1 tooth (1.4%) showed unsatisfactory healing and was asymptomatic. The use as an abutment was found to be a negative factor associated with patient outcome (P < .05; odds ratio = 22; confidence interval, 20.47-23.53). CONCLUSIONS: The combined rate of complete and incomplete healing of teeth 12 to 30 months after endodontic microsurgery was 90.5%. The use as an abutment may have a negative effect on treatment outcome.

[Effects of different cavosurface margins on color matching of the resin composite].

OBJECTIVE: To evaluate effects of color matching of different cavosurface margins on the resin composites in vitro. METHODS: Twenty extracted human premolars with an A2 shade buccal surface were used in this study. Rectangular shaped cavities (3.0 mm depth, 2.0 mm width, 2.0 mm length) were prepared in the center of the buccal surfaces. The gingival and occlusal cavosurface margins were prepared to be either shoulder or bevel; the other cavosurface margins remained vertical. Ten teeth were filled with Clearfil AP-X (AP), the other ten with Clearfil Majesty (MJ) and light cured. The color difference at the cavosurface margin area was measured using a spectrophotometer (CrystalEye) and evaluated by 3 observers subjectively. The data were statistically analyzed using repeated measures ANOVA and Chi-square test. RESULTS: When measured by CrystalEye, the color difference between the tooth and resin composite was reduced from the center of restoration to the cavosurface margin area. Both objective and subjective evaluations showed that for AP, the color difference at the cavosurface margin area had no statistical difference among 3 types of the margins; for MJ, the color difference at bevel margin area was significantly smaller than that at the vertical margin area. CONCLUSION: The resin composite restorations produced the color matching at marginal area. The color matching of resin composites with higher diffused light transmission property is more susceptible to the type of cavosurface margins. Preparing bevels may reduce the color difference between the restoration and tooth surface.

[Effects of hydrogen peroxide-containing bleaching on the growth of Streptococcus mutans biofilm on enamel disc surface].

OBJECTIVE: To evaluate the effects of a commercial bleaching agent containing 35% (mass fraction) hydrogen peroxide on the growth of Streptococcus mutans biofilm on enamel disc surface. METHODS: A total of 20 enamel disks were made from human extracted teeth and the enamel surfaces were kept intact. The discs were autocalved and randomly divided into two groups: bleaching group and control group. Each group contained 10 discs. For bleaching group, the enamel discs were whitened by commercial 35% hydrogen peroxide according to the instruction (Beyond(TM) Professional Dental Whitening Kit, Beyond Technology, TX,USA ); no treatment for control group. All the discs were kept in sterile human saliva for 3.5 hours, and then the mixture of brain heart infusion broth (BHI) medium and Streptococcus mutans were added. The discs and Streptococcus mutans were incubated together in BHI medium with 5% CO(2) (volume fraction), at 37 °C. After 3, 7, 14, 21 and 28 d's incubation, two discs of each group were taken out and the biofilms on the enamel surfaces were evaluated by using conventional bacteria counts and confocal laser scanning microscope (CLSM). The bacteria in the biofilm on one disc enamel surface were analyzed by plating on BHIS agar and the colony-forming units were counted. The biofilm on the other disc surface was stained using a two-colour fluorescent dye kit (Bacerial Viability Kit L-7012) for CLSM. RESULTS: The vital bacteria counts of vital cells in the 3, 7, and 14 d's biofilms of the bleaching group were significantly fewer than those of the control group. Especially in the 3 days' biofilm on the whitened surface, the vital bacteria counts [(3 595 ± 2 903) µm(2) vs. (89 155 ± 65 963) µm(2),t = 8.71,P = 0.00] and proportion of vital bacteria [(26.0% ± 16.4%) vs.(92.2% ± 10.9%), t = 19.93, P = 0.00] were significantly fewer than those of the control. While, for the 21d's biofilm, the vital bacteria counts and the percentage of the vital cells of the bleaching group were more than those of the control group significantly [(66 262 ± 23 772) µm(2) vs. (51 184 ± 20 502) µm(2), t = 2.59, P = 0.012]. CONCLUSION: The hydrogen peroxide-containing bleaching agent may inhibit the growth of Streptococcus mutans biofilm for about 3 weeks; but after 3 weeks, it seems that the bleached surface will increase the growth of biofilm. Whether the whitening therapy will increase caries susceptibility of the bleached surface needs further research.

[Cone-beam computed tomography analysis of root canal configuration of 4 674 mandibular anterior teeth].

OBJECTIVE: To investigate the root canal configuration of mandibular anterior teeth with cone-beam computed tomography (CBCT). METHODS: The CBCT imaging data of 866 patients who visited Peking University School of Stomatology from October 2012 to July 2013 were inspected by an endodontist anda radiologists together. A total of 4 674 mandibular anterior teeth were involved. The number of root, root canals and root canal configuration were observed and analyzed statistically (Chi-squared test). RESULTS: All the mandibular central incisors and lateral incisors were single root, and 0.7% (11/1 542) of canines were double roots. 6.7% (105/1 566) of central incisors, 17.4% (273/1 566) of lateral incisors and 3.0% (46/1 542) of canines had double root canals. The frequency of symmetry of double root canal was 58.7% (37/63) in central incisors, 76.1% (108/142) in lateral incisors and 29.6% (8/27) in canines. The highest frequency of double root canals in different ages was 9.8% (28/287, 31-40 years) in central incisors, 21.5% (61/284, 31-40 years) in lateral incisors and 9.2% (19/207, ≥51 years) in canines. Vertucci type III canal configurations were the most prevalent in mandibular anterior teeth. CONCLUSION: The double root canals are most common in mandibular lateral incisors. The highest incidence of symmetry of double root canal is also observed in mandibular lateral incisors. Vertucci type III canal configurations are the most frequent type in mandibular anterior teeth.

[Effects of thinning on fine-root morphology, biomass and N concentration of different branch orders of Chinese fir].

Taking a 25-year old Chinese fir (Cunninghamia lanceolata) plantation as the object, this paper studied the effects of thinning on the biomass, morphological traits, and nitrogen concentration of the first five orders roots. With the increase of root order (from the first to the fifth order), there was a significant increase in the fine-root biomass, diameter, and tissue density, and a significantly decrease in the specific root length (SRL), root length density (RLD), and root number (RN). Thinning increased the biomass, RLD, and RN of the first and second orders roots as well as the tissue density of the first, third, fourth, and fifth orders roots significantly, but had no effects on the SRL and nitrogen concentration of each order root. In contrast, thinning decreased the diameter of the first, third, and fourth orders roots significantly. The diameter of the second order roots was obviously smaller in surface (0-10 cm) soil than in subsurface (10-20 cm) soil, while the RLD of the first three orders roots and the RN and nitrogen concentration of the first two orders roots were larger in surface soil than in subsurface soil. The interaction of thinning and soil layer only decreased the diameter of the first two orders roots. It was suggested that the fine-root biomass and morphological traits of Chinese fir were closely related to the vegetation growth and regeneration after thinning.

Effects of chlorhexidine, listerine and fluoride listerine mouthrinses on four putative root-caries pathogens in the biofilm.

OBJECTIVE: To investigate the effects of chlorhexidine (CHX), Listerine and Fluoride Listerine on putative root-caries pathogens in the biofilm in the artificial mouth model. METHODS: A total of 24 human dentine discs were prepared. A biofilm composed of Streptococcus mutans, Streptococcus sobrinus, Lactobacillus rhamnosus and Actinomyces naeslundii was cultured on the surfaces of human dentine discs in an artificial-mouth model. Sucrose was supplied by computer-controlled release on a daily basis to simulate the real-life situation. Three treatment reagents, CHX, Listerine and Fluoride Listerine, were supplied at a flow rate of 15 ml/h for 6 min twice a day. The dentine discs with biofilm were removed from the artificial mouth after being cultured for 1, 2, 3, 4, 5 and 6 days. The bacteria in the biofilm were analysed by plating on BHIS agar and the colony-forming units of each species were counted. RESULTS: The total number of bacteria in the CHX group was significantly lower than in the other three groups (including control). There was no decline in the number of bacteria in the Listerine group. S. mutans was reduced significantly in the CHX group compared with the control group. The number and proportion of A. naeslundii in the CHX group were significantly lower than in the other three groups. The proportion of L. rhamnosus in the CHX group was significantly higher than in the other three groups. CONCLUSION: CHX has the most significant effect on inhibition of the putative root-caries bacteria, with the exception of L. rhamnosus. Both Listerine and a combination of fluoride and Listerine could not effectively reduce the numbers of bacteria in the biofilm. The effects of CHX, Listerine and Fluoride Listerine on root caries prevention need further investigation.

[The malocclusion of primary dentition in the suburb of Chengdu: a cross-section survey].

OBJECTIVE: To reveal malocclusion of primary dentition in the suburb of Chengdu. METHODS: Cross-section survey and malocclusion rate calculation were performed. RESULTS: There are 491 children with malocclusion from total 1 279 children; the rate of malocclusion is 38.38%. The most important malocclusion in primary dentition are over bite (III degrees), anterior cross bite, edge to edge bite, early loss of deciduous teeth, fused teeth. CONCLUSION: The rate of malocclusion of primary dentition in the suburb of Chengdu is a little bit light. Much work should be done to prevent or treat the malocclusion of primary dentition.

[Analysis of volatile fatty acids in gingival crevicular fluid of patients with chronic periodontitis].

OBJECTIVE: To investigate the volatile fatty acids in gingival crevicular fluid (GCF) and to analyze the relationship between the levels of the volatile fatty acids and chronic periodontitis. METHODS: GCF samples taken from 37 patients with chronic periodontitis and 16 volunteers with healthy periodontal status were analyzed by capillary electrophoresis. RESULTS: The detection frequencies and concentrations of succinic acid, butyric acid and valeric acid were significantly higher in GCF of chronic periodontitis than in that of healthy group. The detection frequencies of propionic acid had no statistic difference between the two groups, but the concentrations of it was significantly higher in inflammation group. We also found that the concentrations of succinic acid, propionic acid and butyric acid were significantly lower in shallow pockets than that in deep pockets. CONCLUSIONS: The volatile fatty acids, especially succinic acid, propionic acid, butyric acid and valeric acid were associated significantly with the severity and inflammation of periodontal disease. The levels of succinic acid, propionic acid and butyric acid in GCF were related to pocket depth.