Association of obesity and weight gain with alveolar bone loss: Results of the Northern Finland Birth Cohort 1966 study.

AIM: To investigate whether long-term obesity, long-term central obesity and weight gain are associated with alveolar bone loss. MATERIALS AND METHODS: A sub-population (n = 1318) of the Northern Finland Birth Cohort 1966 was categorized based on body mass index (BMI: normal weight, overweight and obesity) and waist circumference (WC: no central obesity, central obesity) at ages 31 and 46. These categories were combined to define whether the participants stayed in the same categories or passed on to a higher category (weight gain). Alveolar bone level (BL) data were collected at age 46. RESULTS: The associations of long-term obesity and weight gain with BL ≥ 5 mm were stronger in smokers than in the total population and in never smokers. Males who passed on to higher BMI and WC categories showed a higher likelihood for BL ≥ 5 mm (range in relative risks [RRs] 1.3-2.2) than males who stayed in the same categories (range in RRs 0.7-1.1). The associations with BL ≥ 5 mm were weak or non-existent in females. CONCLUSIONS: The relation between obesity and periodontal diseases seems more complex than previously presumed. The role of gender and smoking should be taken into account in future studies.

The association of medications with sedative properties with oral health behaviour in community-dwelling older people.

OBJECTIVES: The objective of this study was to determine whether drugs with sedative properties are related to oral health behaviour-such as frequency of toothbrushing, using toothpaste and dental visits-and oral hygiene, measured by the number of teeth with dental plaque, among community-dwelling older people. METHODS: The study population consisted of 159 community-dwelling, dentate, non-smoking, older people from the Oral Health GeMS study (Geriatric Multidisciplinary Strategy for the Good Care of Older People study). The data were collected by interviews and clinical examinations during 2004-2005. Sedative properties of drugs were assessed using the sedative load (SL) model. Logistic and Poisson regression models were used to estimate odds ratios/relative risks (OR/RR) and 95% confidence intervals (CI). RESULTS: After adjusting for confounding factors, SL associated with infrequent toothbrushing (OR 1.72, CI: 0.61-4.89), toothpaste use less than twice a day (OR 3.34, CI: 1.39-8.12), non-regular dental visits (OR 2.28 CI: 0.91-5.30) and the number of teeth with dental plaque (RR 1.20 CI: 1.04-1.39) compared to participants without a SL. CONCLUSIONS: The results of this study suggest that use of drugs with sedative properties indicates poor oral health behaviour among older people.

Role of Employment in 11-Year Changes of Clinical Oral Health: A Multilevel Longitudinal Analysis.

The objective was to investigate the role of employment in the 11-y changes of clinically determined oral health. We used data from the longitudinal Health 2011 Survey, including reinvited subjects from the Health 2000 Survey. Data were gathered by clinical oral examinations, interviews, and questionnaires of those aged 30 to 63 y ( n = 1,031) in 2000. Exposures were change in employment from baseline to follow-up and length of unemployment. Outcomes measures were the numbers of missing teeth, sound teeth, filled teeth, decayed teeth, and teeth with periodontal pockets (≥4 mm and ≥6 mm). Separate mixed-effects and conventional negative binomial regression models were fitted for each oral health outcome. Demographic, socioeconomic, and oral health-related behaviors were added as covariates to the analyses. The findings showed that unemployment was inconsistently associated with poorer clinically determined oral health over 11 y. These effects were attributed to income and education and, to a lesser extent, to oral health-related behaviors. The length of unemployment was also inconsistently associated with oral health. The study concluded that one socioeconomic factor, unemployment, had a partial impact on oral health. Knowledge Transfer Statement: The findings of this study can help clinicians and oral health policy makers to reorient oral health services toward those who are unemployed as a risk group for poor oral health. The research highlights the role of employment in the longitudinal changes of clinically determined oral health, taking into consideration other socioeconomic factors. The study concluded that unemployment seemed to have a role in social inequalities of oral health.

Low serum level of 1,25(OH)2 D is associated with chronic periodontitis.

BACKGROUND AND OBJECTIVES: Vitamin D has been studied primarily for its involvement in calcium and phosphate absorption and bone metabolism. The active form of vitamin D-1,25(OH)2 D-has also been investigated for its immune modulatory properties. We explored associations between serum levels of 25(OH)D and 1,25(OH)2 D and periodontal health. SUBJECTS AND METHODS: This case-control study included 55 subjects with chronic periodontitis (cases) and 30 periodontally healthy subjects (controls). Their serum levels of 25(OH)D, 1,25(OH)2 D, ultrasensitive C-reactive protein and high-density lipoprotein cholesterol were determined. Associations between vitamin D and periodontal health status were studied using logistic regression analysis. RESULTS: A statistically significant association was found between serum 1,25(OH)2 D level and periodontal health status; in that subjects with a low 1,25(OH)2 D were more likely to belong to the periodontitis group (OR = 0.97, 95% CI = 0.95-1.00). There was practically no association between 25(OH)D level and periodontal health status. CONCLUSION: In this case-control study low serum 1,25(OH)2 D level appeared to be associated with periodontitis, which was in line with the previously reported associations between serum 1,25(OH)2 D levels and other inflammatory diseases. Whether this association is causal in nature, remains to be confirmed in future studies.

Body mass index and periodontal infection in a sample of non-smoking older individuals.

OBJECTIVE: The aim of this study was to investigate the association between BMI and periodontal infection in a sample of non-smoking individuals aged 75 years or older. SUBJECTS AND METHODS: The study sample included 157 non-smoking dentate persons (110 women, 47 men, mean age 80.6 years) belonging to the Geriatric Multidisciplinary Strategy for the Good Care of Older People study in Kuopio, Finland. The data were gathered by interview together with geriatric and oral clinical examination. The outcome variable was the number of teeth with periodontal pockets measuring 4 mm or more in depth. Poisson regression models were used to estimate relative risk (RR) and 95% confidence intervals (CI). RESULTS: After adjustment for confounding factors, the relative risk for the number of teeth with deepened periodontal pockets (≥4 mm) was 0.7 (CI: 0.6-0.9) among those with a BMI 25-29.99 and 1.1 (CI: 0.8-1.4) among those with a BMI ≥30, compared with those having a BMI <25. CONCLUSION: Within the limitations of this study, including small sample size, possibility of confounding and other biases, the results do not provide evidence that elevated body weight would be a risk for periodontal infection among older people.

Lysophosphatidic acid and sphingosine-1-phosphate promote morphogenesis and block invasion of prostate cancer cells in three-dimensional organotypic models.

Normal prostate and some malignant prostate cancer (PrCa) cell lines undergo acinar differentiation and form spheroids in three-dimensional (3-D) organotypic culture. Acini formed by PC-3 and PC-3M, less pronounced also in other PrCa cell lines, spontaneously undergo an invasive switch, leading to the disintegration of epithelial structures and the basal lamina, and formation of invadopodia. This demonstrates the highly dynamic nature of epithelial plasticity, balancing epithelial-to-mesenchymal transition against metastable acinar differentiation. This study assessed the role of lipid metabolites on epithelial maturation. PC-3 cells completely failed to form acinar structures in delipidated serum. Adding back lysophosphatidic acid (LPA) and sphingosine-1-phosphate (S1P) rescued acinar morphogenesis and repressed invasion effectively. Blocking LPA receptor 1 (LPAR1) functions by siRNA (small interference RNA) or the specific LPAR1 inhibitor Ki16425 promoted invasion, while silencing of other G-protein-coupled receptors responsive to LPA or S1P mainly caused growth arrest or had no effects. The G-proteins Gα(12/13) and Gα(i) were identified as key mediators of LPA signalling via stimulation of RhoA and Rho kinases ROCK1 and 2, activating Rac1, while inhibition of adenylate cyclase and accumulation of cAMP may be secondary. Interfering with these pathways specifically impeded epithelial polarization in transformed cells. In contrast, blocking the same pathways in non-transformed, normal cells promoted differentiation. We conclude that LPA and LPAR1 effectively promote epithelial maturation and block invasion of PrCa cells in 3-D culture. The analysis of clinical transcriptome data confirmed reduced expression of LPAR1 in a subset of PrCa's. Our study demonstrates a metastasis-suppressor function for LPAR1 and Gα(12/13) signalling, regulating cell motility and invasion versus epithelial maturation.

Salivary flow rate and periodontal infection - a study among subjects aged 75 years or older.

OBJECTIVE: To analyse the relation of stimulated and unstimulated salivary flow rates to periodontal infection in home-dwelling elderly people aged 75 years or older. SUBJECTS AND METHODS: This study was based on a subpopulation of 157 (111 women, 46 men) home-dwelling, dentate, non-smoking elderly people (mean age 79.8, SD 3.6 years) from the Geriatric Multidisciplinary Strategy for the Good Care of the Elderly Study). The data were collected by interview and oral clinical examination. RESULTS: Persons with very low (< 0.7 ml min⁻¹) and low stimulated salivary flow rates (0.7- < 1.0 ml min⁻¹) had a decreased likelihood of having teeth with deepened (≥ 4 mm) periodontal pockets, RR: 0.7, CI: 0.5-0.9 and RR: 0.7, CI: 0.5-0.9, respectively, when compared with those with normal stimulated salivary flow. Persons with a very low unstimulated salivary flow rate (< 0.1 ml min⁻¹) had a decreased likelihood of having teeth with deepened (≥ 4 mm) periodontal pockets, RR 0.8, CI: 0.6-1.0, when compared with subjects with low/normal unstimulated salivary flow. CONCLUSIONS: In a population of dentate, home-dwelling non-smokers, aged 75 years or older, low stimulated and unstimulated salivary flow rates were weakly associated with a decreased likelihood of having teeth with deep periodontal pockets.

Metabolic syndrome, periodontal infection, and dental caries.

Only a few studies have examined the association of metabolic syndrome with periodontal infection and dental caries. The aim in this study was to examine the association of metabolic syndrome with periodontal infection and dental caries using the European Group for the Study of Insulin Resistance (EGIR) definition and its separate components. This study population consisted of dentate, non-diabetic individuals aged 30 to 64 years (N = 2050) who had never smoked. Relative risks (RR) were estimated with Poisson regression models. Metabolic syndrome was associated with teeth with deepened periodontal pockets 4 mm deep or deeper [adjusted RR 1.19 (95% CI 1.01-1.42)], with pockets 6 mm deep or deeper [adjusted RR 1.50 (95% CI 0.96-2.36)], and carious teeth [adjusted RR 1.25 (95% CI 0.93-1.70)]. The results suggest that metabolic syndrome or some of its components are associated weakly with periodontal infection.

Serum sCD14, polymorphism of CD14(-260) and periodontal infection.

BACKGROUND AND AIMS: CD14 is a co-receptor involved in the recognition of Gram-negative and positive bacteria. Infections are known to influence serum sCD14 levels, and CD14 gene promoter polymorphism (CD14 C-260T) has been reported to be associated with many infectious diseases. Our aim was to investigate whether serum sCD14 concentration is associated with periodontal infection and the CD14(-260) genotype. SUBJECTS AND METHODS: The periodontal status of 56 subjects with chronic periodontitis and 28 controls was clinically examined. Serum sCD14 concentration was analyzed using ELISA and CD14(-260) genotype using polymerase chain reaction (PCR). RESULTS: The mean concentration of sCD14 in serum was significantly higher in subjects with periodontitis than in control subjects (4.9 microg ml(-1)vs 3.8 microg ml(-1), P < 0.001). Serum sCD14 concentration associated significantly with the extent of advanced periodontal disease. In a regression analysis including both subject groups, the CD14(-260) genotype was a significant determinant for serum sCD14 concentration. After stratification by periodontal health status (periodontitis vs controls), the influence of the CD14(-260) genotype on serum sCD14 concentration was seen only in the control group. CONCLUSIONS: Periodontal infection is associated with the serum concentration of sCD14. Moderate to severe periodontal infection overshadows the influence of the genotype on serum sCD14 concentration.

Cynical hostility as a determinant of poor oral health status in an adult population.

Our aim in this study was to determine whether there is an association between cynical hostility and clinically determined poor oral health, and whether this association is confounded by socioeconomic position and mediated by health behavior. The sample consisted of 4,207 dentate Finns, 30-64 yr of age. Oral health was measured in terms of numbers of missing teeth, of decayed teeth, and of teeth with periodontal pockets (> or = 4 mm). Cynical hostility was measured using the cynical distrust self-administered questionnaire. The subjects with the highest level of cynical hostility had fewer teeth, and a greater number of decayed teeth as well as teeth with deepened periodontal pockets compared to subjects with the lowest level of cynical hostility. The associations between cynical hostility and number of missing and decayed teeth were clearly confounded by level of education. Poor oral health behavior was shown to be a possible mediator between cynical hostility and number of decayed teeth, but not of missing teeth or teeth with deepened periodontal pockets. General health-related behavior did not serve as a possible mediator in any of the associations. In conclusion, cynical hostility can be considered as a risk marker for poor oral health. Interventions aimed to improve oral health should focus on psychosocial factors and on less-educated subjects.

Sense of coherence associates with oral and general health behaviours.

OBJECTIVE: Our aim was to investigate the mutual relationship between oral and general health behaviours and oral and general subjective health among adults, and to explore whether sense of coherence (SOC) could be a common health-promoting correlate for them. PARTICIPANTS: The present study included data for 4096 30- to 64-year-old dentate adults (2177 females and 1919 males). BASIC RESEARCH DESIGN: In the nationally representative, cross-sectional sample including 8028 persons aged 30, or more, 88% were surveyed. The questionnaire and home interview included information about socio-economic and demographic factors, behavioural and psycho-social variables. Chi-square test and logistic regression models were used in the data analysis. MAIN OUTCOME MEASURES: The main outcome measures were oral health behaviours (regular dental attendance, twice a day tooth-brushing frequency), general health behaviours (non-smoking habits, physical activity at least twice a week), subjective oral and general health and the SOC (12-item) scale. RESULTS: Among females, positive health behaviours tended to occur together significantly more often than among males. Thus, 83% of females with more than once a week physical exercise frequency, and 79% of the non-smoking females, brushed their teeth at least twice a day, while the corresponding figures for the males were merely 55% and 50%. A strong SOC was associated with uniformly positive health behaviours and subjective oral and general health. CONCLUSIONS: Our results suggest that a strong SOC has a universal positive association with several health behaviours and subjective health measures, also concerning oral health. Thus, the role of psycho-social factors should not be underestimated in health promotion.

Expression of fibronectin-binding integrins in gingival epithelium in drug-induced gingival overgrowth.

BACKGROUND AND OBJECTIVE: Gingival overgrowth is a side-effect of nifedipine and cyclosporin medications. Integrins are transmembrane glycoproteins that mediate cell adhesion, regulate cell proliferation and participate in the regulation of tissue fibrosis. The aim of this study was to investigate whether expression of epithelial cell integrins is linked to the development of drug-induced gingival overgrowth. MATERIAL AND METHODS: Human gingival biopsies of patients taking nifedipine, cyclosporin, or a combination of both medications, were used. Expression of the alpha5beta1, alphavbeta1 and alphavbeta6 integrins, and of cellular extra domain A of fibronectin, was localized in frozen sections using immunohistochemistry. RESULTS: The activated conformation of the beta1, alpha5beta1 and alphavbeta6 integrins were more frequently expressed in distinct locations in the oral epithelium in the combined drug group. Cellular extra domain A of fibronectin, a ligand for both alpha5beta1 and alphavbeta6 integrins, was expressed within the connective tissue of all groups. It was also expressed around the basal keratinocytes of the control, nifedipine and cyclosporin-induced gingival overgrowth groups, but not in the combined medication group. No relationship between the presence of inflammation and integrin expression was found. CONCLUSION: The results indicate that expression of certain integrins is up-regulated in the epithelium of drug-induced gingival overgrowth where they could participate in controlling the formation of elongated rete ridges and tissue fibrosis.

Gingivitis, dental caries and tooth loss: risk factors for cardiovascular diseases or indicators of elevated health risks.

OBJECTIVES: The results of earlier studies connecting dental diseases to cardiovascular diseases are inconsistent. Our aim in this cross-sectional study was to investigate whether there are associations of dental diseases and diagnosed angina pectoris among the 1966 Northern Finland Birth Cohort. MATERIALS AND METHODS: A postal questionnaire was sent to all cohort members in 1997-1998. The number of replies totalled 8690. Angina pectoris was determined by asking whether the respondent had been diagnosed with angina pectoris. Gingivitis, dental caries and tooth loss were determined on the basis of self-reported gingival bleeding, presence of dental caries and six or more missing teeth. RESULTS: We found overall associations of gingivitis (odds ratio (OR) 1.52, confidence interval (CI) 1.04-2.22), dental caries (OR 1.50, CI 1.04-2.18) and tooth loss (OR 1.53, CI 0.69-3.42) with the presence of angina pectoris. The associations were modified by gender and socioeconomic status. In addition, gingivitis, dental caries and tooth loss were also associated with several cardiovascular risk factors. CONCLUSION: There were associations of self-reported gingivitis, dental caries and tooth loss with angina pectoris. However, the associations between dental diseases and cardiovascular risk factors suggest that the associations may be because of confounding.

Confounding and effect modification: possible explanation for variation in the results on the association between oral and systemic diseases.

OBJECTIVES: There is large variation in the results of studies on the association between periodontitis and systemic diseases. The variation might be explained by the fact that the association between periodontitis and systemic diseases is confounded, or the association might be modified by extraneous factors. In this article, we show, using simple examples, how confounding and effect modification may cause variation in results. In addition, these examples show that uncontrolled or partially controlled confounders can induce spurious associations. CONCLUSION: Confounding and effect modification may explain the variation in the results of studies on the association between periodontitis and systemic diseases.

Optimism and life satisfaction as determinants for dental and general health behavior-oral health habits linked to cardiovascular risk factors.

Oral infections and cardiovascular diseases share common biological and behavioral risk factors. Psychosocial determinants could act as a link between general health behavior and dental health behavior. Our objective was to study optimism and life satisfaction as determinants of general and dental health behavior and to evaluate whether these are connected with cardiovascular risk factors and dental diseases. The 1966 Northern Finland Birth Cohort (N = 12,058) is a general population birth cohort. In a postal questionnaire, respondents (N = 8690) were asked about their health behavior and dental status. Cardiovascular risk factors were assessed in health examinations (N = 6033). Generalized linear regression models were used in analysis. The results showed that health orientation increases with strengthening life satisfaction and optimism. Dental health behavior and general health behavior were associated with both cardiovascular risk factors and self-reported dental diseases, which support the assumption that they share a common behavioral background.

Improved bone biomechanical properties in xylitol-fed aged rats.

Our previous studies have shown that dietary xylitol protects against weakening of bone biomechanical properties in experimental postmenopausal osteoporosis. To study whether xylitol preserves bone biomechanics also during aging, a long-term experimental study was performed with rats. Twenty-four male Sprague-Dawley rats were divided into 2 groups. The rats in the control group (NON-XYL group) were fed a basal rat and mouse no. 1 maintenance (RM1) diet, while the rats in the experimental group (XYL group) were continuously fed the same diet supplemented with 10% xylitol (wt/wt). The rats were killed after 20 months. Their femurs were prepared for biomechanical analyses and scanning analyses with peripheral quantitative computed tomography (pQCT). In 3-point bending of the femoral diaphysis, maximum load, maximum elastic load, stiffness, energy absorption, elastic energy absorption, ultimate stress, and yield stress were significantly greater in the XYL group than in the NON-XYL group. This indicates a xylitol-induced improvement of both structural and material strength properties of cortical bone. Accordingly, the maximum load of femoral neck was significantly greater in the XYL group. In the pQCT analysis of femoral diaphysis, cortical bone area, cortical thickness (CtTh) periosteal circumference, and cross-sectional moment of inertia were greater in the XYL group. The endosteal circumference was smaller in the XYL group. In the pQCT analysis of the femoral neck cortical area of the midneck was significantly greater in the XYL group. This data indicates that xylitol exerted beneficial effects on the cross-sectional architecture of the bones. In conclusion, continuous moderate dietary xylitol supplementation leads to improved bone biomechanical properties in aged rats concerning both bone structural and material strength properties.

Increased bone volume and bone mineral content in xylitol-fed aged rats.

BACKGROUND: Our previous studies have shown that dietary xylitol supplementation protects against the loss of bone mineral after ovariectomy. The ovariectomy-induced decrease in trabecular bone volume is significantly retarded by dietary xylitol. OBJECTIVE: To study whether dietary xylitol can protect against bone loss also during aging, a long-term experimental study was performed with rats. METHODS: Twenty-four male Sprague-Dawley rats were divided into two groups. The rats in the control group were fed a basal RM1 diet, while the rats in the experimental group were continuously fed the same diet supplemented with 10% (w/w) xylitol. The rats were killed after 20 months. Their tibiae were used for the analyses of bone density and trabecular bone volume, and their femurs were used for the scanning analyses with peripheral quantitative computed tomography (pQCT). RESULTS: The tibial density of the xylitol-fed aged group (1.73 +/- 0.14 g/mm(3)) was significantly greater than that of the aged group without xylitol (1.56 +/- 0.14 g/ mm(3)). The trabecular bone volume of the xylitol-fed rats was 21.2 +/- 4.0%. It was significantly greater than that of the rats not receiving xylitol (9.3 +/- 4.3%). The pQCT-measured cortical bone mineral density and the pQTC-measured cortical bone mineral content of the femoral diaphysis were significantly greater in the xylitol-fed group than in the control group. The trabecular bone mineral density and the trabecular bone mineral content of the femoral distal metaphysis were also significantly greater in the xylitol-fed group than in the non-xylitol group. The total bone mineral density and the total bone mineral content of the femoral neck in the xylitol-fed aged group significantly exceeded those in the aged group without xylitol supplementation. CONCLUSIONS: A continuous moderate dietary xylitol supplementation leads to increased bone volume and increased bone mineral content in the long bones of aged rats. This indicates a xylitol-induced protection against aging-related osteoporotic changes.

Self-efficacy perceptions in oral health behavior.

The aim of this paper is to describe and understand people's views on dental self-efficacy and its formation. The qualitative data were collected by means of focused interviews with five patients selected on the basis of poor orientation to dental-care matters, measured using test scores from a previous questionnaire. The first stage of the analysis is a description of the background of the subjects from their own accounts; two proved to have internalized preventive dental beliefs and behavior deeply while two others had traumatic experiences as a reason for irregular dental appointments. One subject with poor oral health behavior seemed to have limited preventive action to his yearly dental appointment. The second stage of the analysis focuses on interpretation of the subjects' perception of self-efficacy and related comments. Among sources of self-efficacy that prove important in dental care are the cognitive, experiential, supportive and emotional dimensions, and beliefs and values learned in the family and at school. This qualitative research increases our understanding of the oral health behavior of patients and emphasizes the importance of patient-centered oral health education.

Macrophages and lymphocyte subpopulations in nifedipine- and cyclosporin A-associated human gingival overgrowth.

BACKGROUND: Nifedipine and cyclosporin A (CsA) induce gingival overgrowth. Both drugs have immunomodulating effects. It has been suggested that altered immune response is associated with drug-induced gingival overgrowth. In this study, we evaluated whether there were differences in macrophages and lymphocyte subpopulations in human nifedipine- and CsA-associated gingival overgrowth as compared with those in normal gingiva. METHODS: Biopsy samples of overgrown gingiva were obtained from 9 nifedipine-treated cardiac outpatients, 13 CsA-treated renal transplant recipients including 9 patients who were also receiving nifedipine, and 30 healthy control individuals undergoing dental treatment. Serial 5 microm thick cryostat sections were stained with mAbs for CD20 (B-pan), CD68 (macrophages), CD4 (T-helper/inducer), and CD8 (T-cytotoxic/suppressor) using an avidin-biotin-horseradish peroxidase complex method. Numbers of mAb-labeled and all nucleated cells were determined in 3 areas: the connective tissue beneath the sulcular epithelium, the middle connective tissue, and the connective tissue beneath the oral epithelium. Distributions of each type of cell were expressed as percentages of mAb-labeled cells in relation to total number of nucleated cells in a counting zone. Significances of differences between groups were tested by means of the Kruskal-Wallis test, and between pairs of results by means of the Mann-Whitney U-test. RESULTS: The proportion of CD8-labeled cells was significantly higher in connective tissue beneath the sulcular epithelium in the nifedipine group than in the controls (P = 0.014). In both medicated groups, the proportions of CD68-labeled cells were higher in all counting zones than in the controls, but statistically significantly only in the nifedipine group in the connective tissue beneath the oral epithelium (P = 0.008). No intergroup differences were found with respect to CD4- and CD20-labeled cells. The CD4/CD8 ratio was significantly lower in connective tissue beneath the sulcular epithelium in the nifedipine group than in the controls (P= 0.013). CONCLUSION: The results support the idea that immune response may be altered in drug-induced gingival overgrowth.

Mitotic activity of keratinocytes in nifedipine- and immunosuppressive medication-induced gingival overgrowth.

BACKGROUND: The purpose of the study was to compare mitotic activity in the basal cell layer of normal human gingiva and in nifedipine- and immunosuppressive medication-induced gingival overgrowth. METHODS: Gingival samples were collected from 19 generally healthy individuals, 12 nifedipine-medicated cardiac patients, and 22 immunosuppression-medicated (azathioprine, prednisolone, and cyclosporin A) organ transplant recipients. The transplant recipients were divided into those not taking nifedipine and those taking nifedipine. Cryostat sections were stained with monoclonal antibody for Ki-67, using an avidin-biotin-enzyme complex method. The mitotic activities of epithelial cells were determined as percentages of Ki-67 labeled cells in relation to total numbers of epithelial cells in the basal layer of oral, oral sulcular, and sulcular epithelium. RESULTS: Mitotic activities were significantly higher in all 3 medication groups in the oral epithelium (P < or =0.003), and in the immunosuppression group in the sulcular epithelium (P= 0.032) than in the controls. In the oral sulcular epithelium, mitotic activity was fairly similar in all medication groups. In the nifedipine group a significant negative correlation was found between duration of nifedipine medication and the percentage of Ki-67 labeled cells in the oral epithelium (P= 0.025). CONCLUSIONS: The results suggest that the increased epithelial thickness observed in nifedipine- and cyclosporin A-induced gingival overgrowth is associated with increased mitotic activity, especially in the oral epithelium.