[Comparison of clinical effects between periodontal endoscopy aiding subgingival debridement and flap surgery].

OBJECTIVE: To compare the clinical effects of periodontal endoscopy aiding subgingival debridement with periodontal flap surgery on residual deep pockets of chronic periodontitis. METHODS: In the single-blind randomized control clinical study, residual deep pockets of periodontitis patients were still existing when re-evaluation after receiving initial periodontal treatment.The pockets which were necessary for bone surgery or guided tissue regeneration surgery were excluded.The sites were divided into test group and control group randomly.Test group sites underwent periodontal endoscopy aiding debridement and control group sites had periodontal flap surgery.At the baseline and 3 months later, parameters, such as plaque index (PLI), bleeding index (BI), probing depth (PD), attachment loss (AL) were examined.Bone height was measured by parallelly digital X-ray dental film.Meanwhile, treatment time and comfort scale (visual analogue scale, VAS) were also recorded. RESULTS: At baseline, 41 proximal sites with residual deep pockets were enrolled (test sites=21, control sites=20).All the parameters were not significantly different between the two groups.PD decreased by (1.67±0.91) mm from (5.62±0.86) mm to (3.95±0.74) mm in test group and by (2.25±1.12) mm from (5.95±1.19) mm to (3.70±0.73) mm in control group significantly (P < 0.05).The difference between the two groups was not significant.The PD of all the sites decreased lower than 5 mm, meanwhile, 76% was lower than 4 mm in test group and 85% was lower than 4 mm in control group.The BI decreased by 0.81±0.93 in test group and 0.65±0.99 in control group significantly (P < 0.05).The difference between the two groups was not significant.The PLI showed a tendency of decrease more in test group and bone height showed a trend of decrease more in control group, however, the difference was not significant.The treatment time was almost the same.The patients felt more comfortable in the test group (VAS was 0.60±0.89) than the control group (VAS was 1.20±1.64), however, the difference was not significant. CONCLUSION: Periodontal endoscopy aiding subgingival debridement could improve periodontal status by reducing the PD and BI significantly in short term.The effect was almost the same with periodontal surgery and endoscopy treatment may decrease the necessity of surgery.Meanwhile, periodontal endoscopy has more comfortable treatment experience than flap surgery and does not need extra treatment time.

[A survey on human resources of dentists who deal with periodontal disease in Beijing].

Objective: To investigate the status quo of human resources of dentists who deal with periodontal disease in Beijing area through an online survey, which may hopefully provide a preliminary basis for the decision-making of administrative departments and the formulation of periodontal professional development plan. Methods: The dentists who deal with periodontal disease at least half a day per week in Beijing area were investigated. A questionnaire was designed by the chairman of the Periodontology Committee of Beijing Stomatological Association. The questionnaire was sent to and finished by the dentists via "WenJuanXing" online survey software. The contents of the survey included general condition, the property of practice unit, title and position of the dentist, membership of professional society, time and content of periodontal treatment, adoption of new technology and new method of periodontal therapy during the past one year, status of periodontal treatment in the local population and reasons, understanding and influencing factors of periodontal professional development. Results: A total of 1 255 dentists completed the survey, who came from all 16 districts in Beijing, mainly Haidian, Chaoyang, Dongcheng and Xicheng Districts [The total percentage of these four main districts was 70.3% (882/1 255)]. The mean age of the dentists was (36.1±8.3) years. Among the dentists, 71.1% (892/1 255) were females, 88.1% (1 106/1 255) got a Bachelor's degree or above. It was estimated that 35.4% (444/1 255) of the dentists had received standardized periodontal training ever. The percentage of dentists carrying out new technology in the past one year was as high as 68.1% (855/1 255). There were only 163 periodontal specialists (13.0%) out of the dentists in the survey. Only 15.9% (200/1 255) of the dentists routinely performed periodontal surgery. The majority of the dentists [82.8% (1 039/1 255)] were from the state-owned hospitals. Fifty-four point seven percemt (686/1 255) of the dentists thought that lack of knowledge was the main reason why the general public failed to receive periodontal treatment. As for the biggest bottleneck affecting periodontal professional development, fifty-one point zero percent (640/1 255) of the dentists attributed it to the public neglect. Conclusions: The periodontal practitioners in Beijing are young, highly educated, unevenly distributed in 16 districts and mostly females. State-owned oral health institutions are an important force in periodontal diagnosis and treatment services in Beijing. The number of periodontal specialists need to be improved. Promotion of standardized periodontal surgery and the popularization of healthcare knowledge on periodontal disease should also be the focus in the future.

[Comparison of two training protocols in periodontal surgery teaching for undergraduate students].

Objective: To compare the efficacies of two training protocols, i.e. the multimedia instruction and the conventional method, in periodontal surgery teaching for undergraduate students. Methods: One hundred and twenty-three dental undergraduates in their pre-clinical training course were recruited and divided into two groups according to the learning grade matching principle: the experimental group (multimedia instruction, 60 students) and the control group (conventional method, 63 students). The teaching aim was to train the students gingivectomy and periodontal flap surgery by using the pig jaws. The conventional teaching method of teacher-demonstrating and student-practicing was used in the control group, and the practice time of the students' for each surgery was 45 minutes. A standardized teaching video combined with the teachers' explanations of the key steps was used in the experimental group. The students' practice time for each surgery was 60 minutes. The efficacy of teaching protocol was evaluated by the teachers according to the scoring criteria set by the teaching group. Results: In gingivectomy training, accuracy of fixed points, angle of postoperative gingival margin and morphology of gingiva of the experimental group were better than those of the control group. The experimental group also had more complete and continuous excised gingivae and more thorough adjacent gingival removal. The total scores of the experimental group were significantly higher than those of the control group (92.8±2.6 vs. 89.9±3.7, P<0.05). In periodontal flap surgery training, the experimental group operated the blade around the shape of the tooth better in internal bevel incision than the control group. Additionally, the incision position of internal bevel incision, periosteal integrity after flapping and flap depth of the experimental group were better than those of the control group. Besides, the experimental group had smoother flap edge and more thorough debridement. The total scores of the experimental group were significantly higher than those of the control group (92.2±4.1 vs. 89.2±4.4, P<0.05). Conclusions: The teaching efficacy of multimedia instruction was better than that of the conventional method. Its value needs to be further tested in future teaching practice.

[Vestibular incision subperiosteal tunnel access with connective tissue graft for the treatment of Miller classI and II gingival recession].

OBJECTIVE: To evaluate the clinical outcomes of vestibular incision subperiosteal tunnel access (VISTA) with connective tissue graft (CTG) in the treatment of Miller classes I and II localized gingival recession. METHODS: Ten patients with 10 Miller classes I and II localized gingival recessions were enrolled in the study. All defects were equal to or above 2 mm in recession depth. All the patients received treatment with VISTA+CTG. Their clinical parameters, including recession depth (Rec), recession width (RW), keratinized tissue width (KT), clinical attachment loss (CAL), probing depth (PD) were recorded and compared before surgery and 6 months later. The mean root coverage (MRC) and complete root coverage (CRC) were calculated at the end of 6 months. A visual analogue scale (VAS) was used to estimate the patients' discomfort during the operation and during the 2 weeks post-operation. Patient-based aesthetic satisfaction 6 months after surgery was evaluated by a VAS. RESULTS: The mean Rec was (2.65±0.82) mm at baseline, and (0.35±0.58) mm after 6 months. The VISTA+CTG treatment resulted in an improvement of (2.30±0.98) mm in recession depth (P<0.001). MRC was 86.67%±21.94% and CRC reached 70% at the end of 6 months. KT increased (0.90±1.22) mm (P<0.05). Aesthetic satisfaction on the patients' level was 8.30 based on VAS (0=unsatisfied, 10=extremely satisfied). The patients' discomfort during the operation and 2 weeks post operation were 2.40 and 4.30 (0=no pain, 10=extreme pain). Furthermore, clinical outcomes showed no statistically significant difference between the gingival biotypes, and between the teeth positioned in maxillary and in mandibular. CONCLUSION: VISTA+CTG could be an effective treatment for Miller classes I and II localized gingival recession. Clinical outcomes indicated decrease in recession depth and width, and increase in width of keratinized tissue. Patients suffered little pain during the operation and 2 weeks post-operation of healing and accessed good aesthetic satisfaction. VISTA+CTG could be an option for the treatment of Miller classes I and II localized gingival recession.

[Role of vitamin K-dependent protein Gas6 in the expression of endothelial cell adhesion molecule-1 and chemokines induced by Porphyromonas gingivalis lipopolysaccharide].

OBJECTIVE: Growth-arrest-specific protein 6 (Gas6) is a vitamin K-dependent protein and involved in cell proliferation, survival, adhesion and migration . Also it has been shown to play an important role in the inflammatory response .The aim of present study was to investigate the role of Gas6 in the process of the expression of adhesion molecules and chemokines of human umbilical vein endothelial cells (HUVECs) induced by Porphyromonas gingivalis lipopolysaccharide(P.g-LPS). METHODS: After up-regulation and down-regulation of the expression of Gas6, the vascular endothelial cells were stimulated with 1 mg/L P.g-LPS for 3 h and 24 h. Real-time quantitative polymerase chain reaction(real-time PCR) was taken to detect the expression of the cell adhesion molecules:intercellular adhesion molecule-1 (ICAM-1) and E-selectin, as well as chemokines:interleukin-8 (IL-8) and monocyte chemoattractant protein 1 (MCP-1). Wound healing assay was taken to observe the migration ability of endothelium cells in different groups. RESULTS: After 3 h of P.g-LPS stimulation, the expression of adhesion molecules and chemokine in the down-regulation group was not significantly different from that in the control group,while in the up-regulation group the decrease of E-selectin, ICAM-1, IL-8 and MCP-1 was 81%±0%, 47%±3%, 76% ± 3%, 26% ± 6% respectively. After 24 h of P.g-LPS stimulation, the expression of adhesion molecules and chemokine in down-regulation group was significantly higher than that in control group (2.06±0.07, 1.99±0.11, 3.14±0.15, 1.84±0.03 flod), while these molecules in the down-regulation group was significantly lower than in the control group (29%±1%, 62%±3%, 69%±1%, 41%±2%). Differences were statistically significant (P<0.01). Wounding healing assay showed that down-regulation of Gas6 enhanced migration ability of endothelial cells while up-regulation of Gas6 weakened this ability,which was consistent with the trend of real-time PCR result. CONCLUSION: Down-regulation of the Gas6 gene enhanced the expression of ICAM-1, E-selectin, IL-8 and MCP-1 in HUVECs after P.g- LPS stimulating, while up-regulaiton of the Gas6 gene weakened the expression of ICAM-1, E-selectin, IL-8 and MCP-1 in HUVECs after P.g-LPS stimulating,suggesting that Gas6 may play a role in the process of endothelial cell adhesion.

[Observation of bone morphology in furcation defects of mandibular molars using cone beam computed tomography].

OBJECTIVE: To observe mesial-distal bone morphology in classes II and III furcation involvements (FI) of mandibular molars using cone beam computed tomography (CBCT), to develop a classification system of mesial-distal bone morphology of furcation defects and to observe the intrabony defects on CBCT images. METHODS: Based on the existing CBCT data, the mandibular molars with horizontal bone defects in furcation area were observed. One hundred and seventeen sites of 81 mandibular molars with class II or class III FIclassified on CBCT images were included. The classification system of mesial-distal bone morphology of furcation defects was developed. According to the location of the line drawn from mesial to distal alveolar bone crest (AC-line) of the tooth and bone level under furcation fornix, the bone morphology was classified into three types, including concave type, flat type and protruding type. The concave type was divided into two subtypes according to the location of AC-line and furcation fornix (Fx), which were subtype 1(AC-line coronal or equal to Fx)and subtype 2 (AC-line apical to Fx).The frequency of each type was calculated and analyzed. The intrabony defects was observed on sagittal CBCT images. RESULTS: In the 117 sites with FI, the flat type appeared with the highest rate (64.10%) and the protruding type appeared with the lowest rate (6.84%). The rates of subtype 1 and subtype 2 of concave type were 13.68% and 15.38%, respectively. The rate of subtype1 which was supposed to be beneficial for bone regeneration was 8.96% in class II FI and 20.00% in class III FI. Thirtyone intrabony defects were found among the 117 FI, 29 of which appeared in proximal aspect of the tooth and the left 2 appeared in furcation area. The highest frequency of the intrabony defects was found in subtype 1 of concave type. CONCLUSION: The classification of mesial-distal bone morphology on CBCT images may be helpful for clinicians to make accurate treatment plan before surgery and could be used in future studies to understand the influence of bone morphology on regenerative therapy for furcation defects.