Hyperresponsiveness of human gingival fibroblasts from patients with aggressive periodontitis against bacterial lipopolysaccharide.

The present study aimed to investigate whether gingival fibroblasts (GFs) of patients with aggressive periodontitis (AgP) are more sensitive to lipopolysaccharide (LPS) stimulation than GFs of control subjects. AgP causes rapid periodontal destruction, including the production of cytokines [i.e. interleukin (IL)-1ß, IL-6 and tumor necrosis factor (TNF)-α] and matrix metalloproteinases (MMP)-1, -3 and -9 in AgP GFs. LPS upregulates IL-1ß, IL-6, TNF-α, MMP-1, MMP-3, MMP-9 and mitochondrial reactive oxygen species (mtROS). Fibroblasts are known to be associated with immune responses to bacterial virulence factors, but the precise mechanisms underlying this severe periodontal disease are unclear. In the present study, primary human GFs of four patients with AgP and four healthy subjects were challenged in vitro with LPS from Porphyromonas gingivalis (P. gingivalis). The generation of mtROS in GFs was assessed using MitoSOX Red. The expression of genes encoding inflammatory cytokines and MMPs in GFs was analyzed using reverse transcription-quantitative polymerase chain reaction, and the expression of proteins was analyzed using ELISA and Western blotting. Human GFs of patients with AgP exhibited higher levels of mtROS, and higher mRNA and protein expression levels of proinflammatory cytokines, including IL-1ß, IL-6, MMP-1, MMP-3 and MMP-9 compared with healthy human GFs following stimulation with LPS from P. gingivalis. In the present study, it was demonstrated that GFs of patients with AgP display hyperreactivity when challenged with LPS.

Biomarkers in Metabolic Syndrome Patients with Chronic Periodontitis.

OBJECTIVES: To investigate whether the levels of serum C-reactive protein (CRP), salivary interleukin (IL)-6 and IL-lß in metabolic syndrome (MS) patients can be potential monitors for inflammation in MS patients with severe periodontitis. METHODS: A total of 114 MS patients and 49 systemically healthy subjects were enrolled. CRP in serum and IL-1ß and IL-6 in non-stimulated whole saliva were collected from these patients and subjects and analysed by enzyme-linked immunosorbent assay (ELISA). Dental examinations were performed and the participants completed a questionnaire. RESULTS: The serum CRP level of MS patients was higher than that of systemically healthy subjects, and increased as the number of components increased (P < 0.05). No difference was observed in the salivary level of IL-6 and IL-1ß between MS patients and controls or between MS patients with different components. The level of salivary IL-6 in MS patients with moderate/severe periodontitis was significantly higher than in MS patients with good periodontal health/mild periodontitis (P < 0.05). After adjustment for age, sex and smoking habits, multivariate analysis showed that the corresponding odds ratio (OR) for MS combined with moderate/severe periodontitis was 1.21 (95% confidence interval [CI] 1.04-1.39, P = 0.012) for subjects with high serum CRP and salivary IL-6 and IL-1ß were not risk indicators for MS combined with moderate/severe periodontitis. CONCLUSIONS: MS patients might be burdened by high levels of serum CRP. Serum CRP could be a potentially valuable biomarker to detect inflammation in MS patients with severe periodontal disease.

Porphyromonas gingivalis Infection Accelerates Atherosclerosis Mediated by Oxidative Stress and Inflammatory Responses in ApoE-/- Mice.

BACKGROUND: The periodontal pathogen Porphyromonas gingivalis (P. gingivalis) has been proven to accelerate the development of atherosclerosis in apolipoprotein E (ApoE)-deficient mice. In this study, we used an ApoE knockout (ApoE-/-) mouse model with chronic intravenous infection with P. gingivalis to investigate the possible mechanisms of P. gingivalis-induced atherosclerosis. METHODS: Eight-week-old ApoE-/- mice were randomly assigned to two groups: (a) ApoE-/- + PBS (n = 8); (b) ApoE-/- + P. gingivalis (n = 8). Both of the groups received intravenous injections 3 times per week. After 4 weeks, oxidative stress mediators in serum, heart, aorta, and liver tissues were analyzed by using histology, ELISA, realtime PCR, and Western blot. RESULTS: Development of atherosclerosis as plaque formation in the aorta has been confirmed upon P. gingivalis infection. An abnormal lipid profile was found in the serum (increased amounts of very low-density lipoprotein [vLDL] and oxidized low-density lipoprotein [oxLDL], and decreased amount of HDL) and in some organs including heart, aorta or liver (increased mRNA levels of oxidized low-density lipoprotein receptor-1 [LOX-1] or fatty acid synthase [FAS]). Meanwhile, aggravated oxidative stress (higher level of reactive oxygen species [ROS] in the serum, and increased mRNA levels of nicotinamide adenine dinucleotide phosphate oxidase [NOX]-2 and/or NOX-4 in the three organs) was observed, as well as enhanced inflammatory responses (increased expression and secretion of C-reactive protein [CRP] in the liver and serum, and increased mRNA levels of cyclooxygenase-2 [NOX-2] and/or inducible nitric oxide synthase [iNOS] in the three organs). Besides, inflammatory mediators including nuclear factor of kappa B (NF-κB) and iNOS showed increased protein levels in the three organs after P. gingivalis infection. CONCLUSIONS: These results suggest that chronic intravenous infection with P. gingivalis in ApoE-/- mice could accelerate the development of atherosclerosis, possibly associated with mediating oxidative stress as well as inflammatory responses and disturbing the lipid profile.

Tanshinone IIA Attenuates Atherosclerosis in Apolipoprotein E Knockout Mice Infected with Porphyromonas gingivalis.

Tanshinone IIA (TSA), a pharmacologically active component isolated from Danshen, may prevent cardiovascular diseases due to its anti-inflammatory, anti-oxidative, and anti-adipogenic effects. Porphyromonas gingivalis, a major periodontal pathogen, may contribute to the progression of atherosclerosis. Here, we studied the effects of TSA on atherosclerosis in ApoE-/- mice with P. gingivalis infection. Eight-week-old ApoE-/- mice were randomized to (a) phosphate-buffered saline (PBS), (b) P. gingivalis, and (c) P. gingivalis + TSA (60 mg kg-1 day-1). The mice were injected with (a) PBS, or (b) and (c) P. gingivalis 3 times per week for a total of 10 times. After 8 weeks, atherosclerotic risk factors in serum and in heart, aorta, and liver tissues were analyzed in all mice using Oil Red O, atherosclerosis cytokine antibody arrays, enzyme-linked immunosorbent assay (ELISA), real-time PCR, and microRNA array. CD40, G-CSF, IFN-γ, interleukin (IL)-1ß, IL-6, MCP-1, MIP-3α, tumor necrosis factor-α (TNF-α), and VEGF were attenuated by TSA in atherosclerosis cytokine antibody arrays. TSA-treated mice showed a significant reduction of C-reactive protein (CRP), ox-LDL, IL-1ß, IL-6, IL-12, and TNF-α in ELISA data. Real-time PCR analyses showed that TSA decreased the expression of CCL-2, CD40, IL-1ß, IL-6, TNF-α, and MMP-2 in heart and aorta tissues. Moreover, hepatic CRP was downregulated by TSA, although FASN and HMG-CoA were not. The relative expressions of miR-146b and miR-155 were elevated by P. gingivalis infection and were downregulated by TSA treatment. These results suggest that TSA was a potential therapeutic agent that may have the ability to prevent P. gingivalis-induced atherosclerosis associated with anti-inflammatory and anti-oxidative effects.

Mitochondrial reactive oxygen species mediate the lipopolysaccharide-induced pro-inflammatory response in human gingival fibroblasts.

Although periodontal diseases are initiated by bacteria that colonize the tooth surface and gingival sulcus, the host response is believed to play an essential role in the breakdown of connective tissue and bone. Mitochondrial reactive oxygen species (mtROS) have been proposed to regulate the activation of the inflammatory response by the innate immune system. However, the role of mtROS in modulating the response of human gingival fibroblasts (HGFs) to immune stimulation by lipopolysaccharides (LPS) has yet to be fully elucidated. Here, we showed that LPS from Porphyromonas gingivalis stimulated HGFs to increase mtROS production, which could be inhibited by treatment with a mitochondrial-targeted exogenous antioxidant (mito-TEMPO) or transfection with manganese superoxide dismutase (MnSOD). A time-course study revealed that an increase in the concentration of mtROS preceded the expression of inflammatory cytokines in HGFs. Mito-TEMPO treatment or MnSOD transfection also significantly prevented the LPS-induced increase of interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α. Furthermore, suppressing LPS-induced mtROS generation inhibited the activation of p38, c-Jun N-terminal kinase, and inhibitor of nuclear factor-κB kinase, as well as the nuclear localization of nuclear factor-κB. These results demonstrate that mtROS generation is a key signaling event in the LPS-induced pro-inflammatory response of HGFs.

[Effects of Er, Cr: YSGG laser on the root surface of periodontitis and healthy teeth].

OBJECTIVE: To evaluate the effects of Er, Cr: YSGG laser on the root surface of periodontally involved teeth and healthy teeth, concerning the microstructure and the roughness. METHODS: Eight freshly extracted teeth due to severe periodontitis and eight freshly extracted teeth due to orthodontic reasons or being third molar were chosen in this study. The root surface of each tooth was divided into four areas, and received four treatment METHODS: no treatment (control group); root planing with Gracey scaler for 30 seconds; irradiation by the lower power Er, Cr: YSGG laser; irradiation by the higher power Er, Cr: YSGG laser. Four periodontally involved teeth and four healthy teeth were used for the evaluation of microstructure using scanning electron microscope (SEM). The other four periodontitis teeth and four healthy teeth were used for the evaluation of roughness (Ra value) using 3D profiler. RESULTS: Smear layer was found on the teeth scaled by Gracey scaler, while the teeth irradiated by Er, Cr: YSGG laser demonstrated a melting surface with less smear layer. In the periodontitis teeth irradiated by the higher power, opening dentinal tubules could be observed. For the periodontally involved teeth, the Ra values of groups 1 to 4 were (237.4 ± 20.0) nm, (135.7 ± 11.9) nm (P=0.01), (463.6 ± 49.3) nm (P<0.001) and (486.0 ± 59.0) nm (P<0.001) respectively. For the healthy teeth, the Ra values of groups 1 to 4 were (191.4 ± 44.5) nm, (131.6 ± 21.5) nm (P=0.482), (463.7 ± 34.6) nm (P<0.001) and (470.3 ± 121.3) nm (P<0.001) respectively. CONCLUSION: Er, Cr: YSGG laser can affect the microstructure of the cementum of the periodontitis teeth and healthy teeth. Irradiation by the Er, Cr: YSGG laser resulted in a melting surface with less smear layer and increased the roughness in the surface of root.

[Chronic periodontitis with Takayasu arteritis: a case report].

This case report concerns a 23-year-old woman with chronic periodontitis who had been previously diagnosed with Takayasu arteritis (TA). Her erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) level were decreased before and 3 months after non-surgical periodontal therapy with no change in her prescribed medications (ESR from 31.00 mm/h to 23.0 mm/h, CRP from 21.40 mg/L to 18.46 mm/h). Through the occasional findings, we raised a hypothetical analysis about the potential relationship between periodontitis and TA with respect to inflammatory factors, bacteria and medication. Further studies of large samples are needed to verify the findings.

[Association between chronic periodontitis and metabolic syndrome related mitochondria single nucleotide polymorphism].

OBJECTIVE: To investigate the relationship between Mitochondrial DNA(mtDNA) SNP and the severity of periodontitis. METHODS: In the study, 227 subjects in a community of Beijing received questionnaire interview, periodontal examination and biochemical laboratory examination in 2005. The designed primer was used to amplify the specific mtDNA fragments with PCR, and sequence the PCR products. Finally, the relationship between severity of chronic periodontitis and mtDNA SNP at site 10398 was analyzed. RESULTS: The number of the subjects included at mtDNA site 10398 was 227. The G allele frequency in the metabolic syndrome(MS) subjects was significantly higher than that in the non MS subjects [80(70.2%) vs. 34(29.8%),P=0.039 ]. The result of Logistic regression showed that the subjects with G allele had higher risk of MS than the subjects with A allele(OR=1.77,95%CI=1.02-3.06, P=0.042). But there was no significant relationship between the 10398 A→G SNP and severity of periodontitis. CONCLUSION: In this population, mtDNA SNP 10398 A→G may be associated with MS. However, there was no relationship between the 10398 A→G SNP and severity of chronic periodontitis.

[Periodontal status of patients with post-acute myocardial infarction].

OBJECTIVE: To evaluate the periodontal status of post-acute myocardial infarction patients, to identify whether periodontitis is associated with post-acute myocardial infarction in Chinese community population. METHODS: Case and control subjects were enrolled from a community population, the diagnose of post-acute myocardial infarction and systemic health were based on blood, electrocardiogram and ultrasound examinations by physicians. Full mouth periodontal examinations were performed in 103 post-acute myocardial infarction patients and 52 healthy subjects. Mesial-buccal and distal-lingual sites per tooth were examined. The periodontal parameters including plaque index (PLI), bleeding index (BI), probing depth (PD), attachment level (AL) and missing teeth number were recorded. Information of demographic data, behavior habits and general conditions were obtained by a questionnaire. Periodontal status were compared between case and control groups, the association between AL, PD, PLI, missing teeth and post-acute myocardial infarction was analyzed by Logistic regression. RESULTS: In post-acute myocardial infarction group, there were 83 males, 20 females, mean age was 68(41 to 84)years old, in healthy subjects there were 30 males and 22 females,mean age was 62(42 to 78) years old. There were no statistically differences between two groups in age structure, smoking condition, education status and working condition, but body mass index, total cholesterol, triglycerides and glucose in post-acute myocardial infarction group were significantly higher than that in healthy group,while high-density lipoprotein significant lower . The number of missing teeth(6.89±7.39 vs. 4.21±5.62, P=0.01), mean AL [(3.48±2.34) mm vs. (2.61±1.85) mm, P=0.02] and prevalence of severe periodontitis (44.7% vs. 32.7%, P<0.01) were significantly higher in post-acute myocardial infarction patients than that in healthy subjects. Plaque index (1.69±0.49 vs. 1.57±0.50, P=0.22), PD (2.88±1.02 vs. 2.64±0.68, P=0.09) were higher in post-acute myocardial infarction patients than that in healthy subjects, but not statistically significant. In the multivariate analysis, after adjusting sex, age, smoking, body mass index, diabetes, hypertension and serum lipid, AL≥4.00 mm was a significant risk indicator for post-acute myocardial infarction(odd ratio 4.89, 95%confidence interval 1.26 to 18.94, P=0.02). CONCLUSION: Periodontal status was worse in post-acute myocardial infarction patients than that in healthy subjects, AL≥4.00 mm was an independent risk indicator for post-acute myocardial infarction.

[Correlation between periodontitis and metabolic syndrome of the middle-aged and aged population in Shijingshan community of Beijing].

OBJECTIVE: To survey the metabolic status of the middle-aged and aged population with periodontitis in Shijingshan community of Beijing, and investigate the relationship between periodontitis and metabolic syndrome (MS). METHODS: The middle-aged and aged population in the community were investigated by questionnaires, periodontal clinical examinations and blood biochemical tests in 2005. A total of 903 subjects were enrolled, who were divided into two groups by severity of periodontitis. Their waist circumferences, values of high-density lipoprotein cholesterol (HDL-C), systolic blood pressure, fasting glucose, MS and its individual components (central obesity, insulin resistance, hypertriglyceridemia, low HDL-C and hypertension) were compared between the two groups. The Logistic regression model was set to analyze the relationship between periodontitis and MS. RESULTS: There was a significantly higher mean of systolic blood pressure, fasting glucose in the subjects with moderate-severe periodontitis than that with no-mild periodontitis. With severity of periodontitis increasing, the prevalence of MS, high blood glucose and low HDL-C increased significantly. After adjustment for gender, age, and smoking, the subjects with moderate-severe periodontitis were 1.524, 1.527 and 2.349 times more likely to suffer from MS, high blood glucose and low HDL-C than those with no-mild periodontitis, respectively. CONCLUSION: With severity of periodontitis increasing, the prevalence of MS, high blood glucose and low HDL-C increased significantly in the middle-aged and aged population of the community in Beijing. Severity of periodontitis is associated with MS, high blood glucose and low HDL-C.

[Effect of supportive periodontal therapy in maintaining the long-term effect of the initial therapy].

OBJECTIVE: To evaluate the influence of supportive periodontal therapy to the long-term effect after initial therapy. METHODS: The investigation was conducted as a retrospective longitudinal study over a period of at least 2 years, a total of 39 patients recruited in the study and divided into non-maintenance group (n=22) and maintenance group (n=17). Non-maintenance group were monitored for an average of 5.09 years, maintenance group were monitored for an average of 7.53 years. The changes of following variables were recorded and analyzed: the number of loss tooth, probing depth (PD), bleeding index, alveolar bone level in full mouth radiographs. RESULTS: It was observed that (1) patients without maintenance lost more teeth compared to the maintenance groups, showed no changes of PD percentage but significant decrease in bone level; (2) patients received maintenance showed significant decreases in PD, bone level keep stable during the observation compared to the non-maintenance group. CONCLUSION: Supportive periodontal therapy not only decreased the probing depth, but also prevented alveolar bone loss. Supportive periodontal therapy after initial therapy plays a crucial role in keeping periodontal health for long-term.

[Effects of bio-glass in subgingival scaling and root planing].

OBJECTIVE: To evaluate the effect of locally applied bio-glass on the teeth hypersentivity and periodontal recovery after subgingival scaling and root planing. METHODS: In this double blind study, 60 patients with chronic periodontitis were included and were randomly divided into four groups of 15 patients: bio-glass powder and bio-glass paste group (Po+Pa), bio-glass powder group (Po), bio-glass paste group (Pa) and control group. Powder was applied in pockets after subgingival scaling and root planning (SRP) and paste was used as toothpaste for 6 weeks. Periodontal indices and the severity of tooth hypersensitivity were recorded. RESULTS: Obvious mitigation of tooth hypersensitivity was observed in bio-glass powder or paste applied patients within the fist three weeks after SRP. Only few patients presented teeth hypersensitivity in the 6th week after SRP. In the 6th week after SRP, bleeding index significantly decreased in bio-glass powder or paste applied patients. More pocket depth and clinical attachment level reduction was found in bio-glass powder applied patients. Application of bio-glass powder or paste improved clinical attachment level in the 3rd month after SRP. CONCLUSION: The hypersensitivity after subgingival scaling could be relieved without any treatment in 6 weeks, while the bio-glass powder and the 7% bio-glass paste could reduce the prevalence and the severity of it. Further more, bio-glass also improved the clinical outcomes of subgingival scaling via its bacteriostatic action.

[Levels of tumor necrosis factor-alpha and interleukin-1beta in saliva of metabolic syndrome patients].

OBJECTIVE: To investigate the association between periodontitis and the low-grade inflammation in metabolic syndrome (MS) patients. METHODS: Fifty-seven MS patients, 26 healthy controls were enrolled. Non-stimulated whole saliva was collected. The levels of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta was analyzed by radioimmunoassay and enzyme-linked immunosorbent assay, respectively. Concentration of cytokines was compared between MS patients and the healthy controls. Correlations between the cytokines and various periodontal indices, and between the cytokines level and different quantity of metabolic syndrome components were also investigated. RESULTS: Levels of TNF-alpha in saliva of MS patients [(69.30+/-21.01) ng/L] were significantly higher than that in the healthy subjects [(57.85+/-15.69) ng/L, P<0.05], and of IL-1beta in MS patients [(616.42+/-360.05) ng/L] higher than that in healthy subjects [(506.06+/-245.76) ng/L], but the difference was not statistically significant. TNF-alpha was positively correlated with bleeding index (BI). In MS patients, TNF-alpha level and IL-1beta level increased with increasing severity of periodontal disease and increasing component numbers of MS. CONCLUSIONS: Periodontal inflammation may be one of the sources of low-grade inflammation in MS patients. Both systemic and periodontal conditions may influence the level of salivary TNF-alpha and IL-1beta.

Relationship of metabolic syndrome to chronic periodontitis.

BACKGROUND: Many studies have suggested that periodontal disease is related to metabolic disorders. Few studies have investigated metabolic syndrome (MS), as defined by the International Diabetes Federation in 2005, in the Chinese population. The aim of this study was to assess the association of periodontitis with MS. METHODS: In this case-control study, 152 patients with MS and 56 generally healthy adults received a comprehensive clinical dental examination. Attachment loss, probing depth, bleeding index, and plaque index were examined at two sites per tooth (mesio-buccal and disto-lingual). The number of missing teeth was noted in each subject. RESULTS: The male patients with MS were significantly younger and their periodontal parameters were significantly higher than those of the healthy group. The female patients with MS were significantly older, and all periodontal parameters were higher than those in the healthy group; only plaque index was statistically significantly different (P = 0.001). After adjustment for gender, age, and smoking, the corresponding adjusted odds ratios for MS were 6.9 (95% confidence interval [CI]: 1.07 to 44.77), 9.9 (95% CI: 1.50 to 65.24), and 15.6 (95% CI: 2.20 to 110.43) for subjects with attachment loss > or = 3 mm in >0% to 33% of sites, >33% to 67% of sites, and >67% of sites, respectively. Most periodontal parameters were highest in patients with four components of MS, but these differences were not statistically significant. CONCLUSION: Patients with MS had poor periodontal conditions, and periodontal disease was associated with MS, independent of other risk factors.

[Computerized image processing in esthetic rehabilitation of anterior teeth].

OBJECTIVE: To investigate the application of computerized image processing in esthetic rehabilitation of anterior teeth. METHODS: Thirteen patients with esthetic problems in anterior teeth were included in this study. Oral digital images were obtained before and during treatment with a digital camera. All the oral esthetic data of the patients, including tooth shape, tooth shade, tooth characteristic color, incisal transparency, incisal curve, smile line, and gingival curve et al, were collected and analyzed. Diagnostic images of the anticipated esthetic outcome were created by computerized image processing software and transferred to the technician. Restorations were made according to the images by the technician. RESULTS: All anterior teeth of 13 patients were restored with this method and good esthetic results were achieved. CONCLUSIONS: Computerized image processing is a useful method in the esthetic rehabilitation of anterior teeth.

[Effect of verapamil on the proliferation of normal gingival fibroblast].

OBJECTIVE: To evaluate the effect of verapamil on the proliferation of normal gingival fibroblast (NGF) in vitro. METHODS: NGF was isolated and cultured. The 5th passage of NGF was incubated with 0, 0.1, 1, 10, 100 micromol/L verapamil respectively. Methyl thiazolyl tetrazolium (MTT) assay and flow cytometry were used to detect cell proliferation and cell cycles. RESULTS: Incubated with 100 micromol/L verapamil for 66 h, the A value of normal gingival fibroblast was significantly lower than those without verapamil groups (P < 0.01). Incubated with 100 micromol/L verapamil for 18 h, 69% of cells were at the G(0) - G(1) phase, 27% were at the S phase. For control group (without verapamil) 41% of cells were at G(0) - G(1) phase and 49% cells were at S phase. There was significant difference between the two groups (P < 0.001). CONCLUSIONS: 100 micromol/L verapamil inhibited proliferation of normal gingival fibroblast by a cell-cycle arrest.

[Analysis of dental plaque by using cellular neural network-based image segmentation].

OBJECTIVE: To establish and evaluate a new method for measurement of dental plaque by using cellular neural network-based image segmentation. METHODS: A total of 195 subjects were selected from community population. After dental plaque staining, oral digital picture of anterior teeth area was taken by an Olympus digital camera (C-7070 Wide Zoom). At the same time, the Turesky dental plaque indices of anterior teeth were evaluated. The image analysis was conducted by cellular neural network-based image segmentation. RESULTS: The image cutting errors between two operators were very small. The Kappa value is 0.935. Pearson's correlation coefficient is 0.988 (P < 0.001). There was high correlative consistency between traditional dental plaque index and plaque percentage obtained by using image analysis. Pearson's correlation coefficient was 0.853 (P < 0.001). CONCLUSIONS: Cellular neural network-based image segmentation is a new method feasible for evaluating dental plaque.

[Analysis of risk indicator for nifedipine-induced gingival hyperplasia].

OBJECTIVE: To investigate the prevalence and risk indicator of nifedipine-induced gingival overgrowth in a community population in Beijing. METHODS: A cross-sectional survey was conducted in 616 community subjects with hypertension or coronary vascular disease in Beijing, China. Among them 205 individuals took nifedipine for at least half year and 411 individuals who had never received calcium channel blocker (CCB) were recruited as controls. Smoking, oral hygienic habit, systemic health, pharmacological and demographic data for each subject were recorded by questionnaire. Sulcus bleeding index (SBI) was assessed in 12 anterior teeth per subject. Turesky modified Quigley-Hein plaque index (PI) and gingival overgrowth index in anterior teeth were scored on photograph. 38.6% was defined as threshold to identify individual with significant gingival overgrowth. RESULTS: 7.3% of the subjects taking nifedipine were found to have significant gingival overgrowth in this population. The prevalence of gingival overgrowth in nifedipine group was statistically higher than that in the control group. By logistic regression analysis, SBI was found to be the only risk indicator (odds ratio = 5.92, P = 0.001). CONCLUSIONS: The presence of gingival inflammation was an important cofactor for the occurrence of gingival overgrowth.