The effect of a hypocalcemic diet on the periodontal structures of the adult rat

Association of bone mineral density with periodontal status in postmenopausal women

AIM

Menopausal changes expose an individual towards risk of various pathologies during midlife transition. This study aimed to investigate the possible association of bone mineral density (BMD) with periodontal parameters in early postmenopausal Indian women.

METHODS

In 78 dentate postmenopausal female patients periodontal examination was performed including clinical attachment loss, pocket depth, plaque index and sulcular bleeding index. Alveolar crestal height was measured on proximal surfaces of all posterior teeth except third molars with the help of bitewing radiographs. Patient's BMD was assessed with dual energy X-ray absorptiometry. Statistical analysis was performed to assess the correlation between BMD and periodontal parameters.

RESULTS

Pocket depth, clinical attachment loss and alveolar crestal height were found to have negative and statistically significant (P = -0.000 each) correlation with T-score, with the value of Pearson's correlation coefficient being -0.474, -0.426, and -0.419 respectively. Number of teeth lost due to periodontitis was not significantly correlated with T-score (P > 0.05). Results of anova and the post-hoc Tukey test revealed a statistically significant difference of mean clinical attachment loss, pocket depth and alveolar crestal height for the osteoporotic versus osteopenic group and the osteoporotic versus normal group. However, between the osteopenic and normal group, the differences of mean were statistically nonsignificant (P > 0.05). Body mass index was found to have a weakly positive (r = 0.376) and statistically significant (P = 0.001) correlation with T-score.

CONCLUSIONS

Bone mineral density is an important risk indicator for periodontitis in postmenopausal women. Number of teeth lost due to periodontitis is not significantly affected by the BMD of the early postmenopausal phase.

Dietary-induced hyperparathyroidism affects serum and gingival proinflammatory cytokine levels in rats

BACKGROUND

Poor diet and inadequate nutrition are suggested to affect the periodontium as well as impair the systemic health. This study investigated the systemic and periodontal effects of dietary-induced hyperparathyroidism (dHPT) by evaluating serum and gingival proinflammatory cytokine levels.

METHODS

Twenty-four Sprague-Dawley rats were used in the study. dHPT was induced in 12 rats by calcium/phosphorus imbalance, and 12 rats were fed a standard diet (SD). Afterward, endotoxin-induced periodontitis was induced on the right mandibular molar teeth (mmt). Four study groups were created: dHPT + mmt without periodontitis (group 1), dHPT + mmt with periodontitis (group 2), SD + mmt with periodontitis (group 3), and SD + mmt without periodontitis (group 4). Interleukin (IL)-1beta and tumor necrosis factor-alpha (TNF-alpha) levels were measured by enzyme-linked immunosorbent assay to evaluate the proinflammatory cytokine profiles. Serum cytokines were analyzed in the blood samples collected prior to periodontitis induction, whereas gingival cytokines were analyzed in the gingival supernatants of the four groups.

RESULTS

Serum cytokines were higher in dHPT rats than in SD rats (P <0.001), with a positive correlation between parathormone and the cytokines (P <0.001). Gingival cytokines were highest in group 2 and lowest in group 4 (group 2 > group 3 > group 1) (P <0.001). There was a positive correlation between parathormone and the gingival cytokines in group 1 (P <0.001 for IL-1beta; P <0.01 for TNF-alpha).

CONCLUSION

The results suggested that increased serum proinflammatory cytokine production may be a complication of dHPT, and this may affect healthy and diseased periodontia by increasing gingival proinflammatory cytokine levels.

Calcium and vitamin D supplements reduce tooth loss in the elderly

PURPOSE

Oral bone and tooth loss are correlated with bone loss at nonoral sites. Calcium and vitamin D supplementation slow the rate of bone loss from various skeletal sites, but it is not known if intake of these nutrients affects oral bone and, in turn, tooth retention.

SUBJECTS AND METHODS

Tooth loss was examined in 145 healthy subjects aged 65 years and older who completed a 3-year, randomized, placebo-controlled trial of the effect of calcium and vitamin D supplementation on bone loss from the hip, as well as a 2-year follow-up study after discontinuation of study supplements. Teeth were counted at 18 months and 5 years. A comprehensive oral examination at 5 years included assessment of caries, oral hygiene, and periodontal disease. The odds ratio (OR) and 95% confidence interval (CI) of tooth loss were estimated by stepwise multivariate logistic regression. Initial age (mean +/- SD) of subjects was 71 +/- 5 years, and the number of teeth remaining was 22 +/- 7.

RESULTS

During the randomized trial, 11 of the 82 subjects (13%) taking supplements and 17 of the 63 subjects (27%) taking placebo lost one or more teeth (OR = 0.4; 95% CI: 0.2 to 0.9). During the 2-year follow-up period, 31 of the 77 subjects (40%) with total calcium intake of at least 1000 mg per day lost one or more teeth compared with 40 of the 68 subjects (59%) who consumed less (OR = 0.5; 95% CI: 0.2 to 0.9).

CONCLUSION

These findings suggest that intake levels of calcium and vitamin D aimed at preventing osteoporosis have a beneficial effect on tooth retention.

The relationship between bone mineral density and periodontitis in postmenopausal women

BACKGROUND

Systemic bone loss has been proposed as a risk factor for periodontal disease; however, the relationship between these two diseases is still not clear. The objective of this study was to assess the relationship between systemic bone mineral density and periodontal disease, controlling for known confounders.

METHODS

The study population included 70 postmenopausal Caucasian women aged 51 to 78 (mean +/- SD: 62.10 +/- 7.1 years). Skeletal bone mineral density (BMD) was assessed by dual energy x-ray absorptiometry (DXA) at the neck, trochanter, intertrochanter, Ward's triangle, and total regions of the femur, and from the anterior-posterior view of the lumbar spine. Periodontal disease severity was represented by clinical attachment loss (CAL) and interproximal alveolar bone loss (ABL). Other measures of periodontal status included probing depth (PD), supragingival plaque, gingival bleeding on probing, and calculus. DXA and oral examinations were performed by calibrated examiners. Partial correlation coefficients (r) were obtained from multiple linear regression analysis adjusting for age, age at menopause, estrogen supplementation, cigarette smoking, body mass index, and supragingival plaque.

RESULTS

Mean ABL was significantly correlated with BMD of the trochanter (r =- 0.27), Ward's triangle (r = -0.26), and total regions of the femur (r = -0.25). Mean CAL appeared to be related to BMD consistently at all regions of the skeleton, although the association did not reach statistical significance.

CONCLUSIONS

We can conclude that skeletal BMD is related to interproximal alveolar bone loss and, to a lesser extent, to clinical attachment loss, implicating postmenopausal osteopenia as a risk indicator for periodontal disease in postmenopausal Caucasian women.

Calcium and the risk for periodontal disease

BACKGROUND

Dietary calcium has long been a candidate to modulate periodontal disease. Animal as well as human studies of calcium intake, bone mineral density, and tooth loss provide a rationale for hypothesizing that low dietary intake of calcium is a risk factor for periodontal disease.

METHODS

We evaluated the role of dietary calcium intake as a contributing risk factor for periodontal disease utilizing the Third National Health and Nutrition Examination Survey (NHANES III), which is representative of the U.S. civilian non-institutionalized population. Dietary calcium intake was determined from a 24-hour dietary recall. The U.S. Department of Agriculture Nutrient Database was used as a source of nutrient composition data. Periodontal disease was measured by attachment loss. In addition, serum calcium was assessed using venous blood samples. Logistic regression analysis was used to examine the association between periodontal disease and dietary calcium intake or serum calcium levels after adjusting for covariants including age, gender, tobacco consumption, and gingival bleeding.

RESULTS

The association of lower dietary calcium intake with periodontal disease was found for young males and females (20 to 39 years of age), and for older males (40 to 59 years of age). The relationship between low dietary calcium intake and increased levels of periodontal disease showed an estimated odds ratio (OR) of 1.84 (95% CI: 1.36 to 2.48) for young males, 1.99 (95% CI: 1.34 to 2.97) for young females, and 1.90 (95% CI: 1.41 to 2.55) for the older group of males. These odds ratios were adjusted for gingival bleeding and tobacco consumption. The dose response was also seen in females, where there was 54% greater risk of periodontal disease for the lowest level of dietary calcium intake (2 to 499 mg) and 27% greater risk in females who took moderate levels of dietary calcium (500 to 799 mg) as compared to those who took 800 mg or more dietary calcium per day. A statistically significant association between low total serum calcium and periodontal disease was found in younger females aged 20 to 39 with OR = 6.11 (95% CI: 2.36 to 15.84) but not for males or older females, after adjusting for tobacco use, gingival bleeding, and dietary calcium intake.

CONCLUSIONS

These results suggest that low dietary intake of calcium results in more severe periodontal disease. Further studies will be needed to better define the role of calcium in periodontal disease and to determine the extent to which calcium supplementation will modulate periodontal disease and tooth loss.

Influence of obesity and hypertension on the severity of periodontitis in rats

The purpose of this investigation was to evaluate the extent to which obesity and/or hypertension may modify the response of rats' periodontium to chronic gingival irritation. Forty-four normal, spontaneously hypertensive, obese, and obese-hypertensive rats were used. Histopathologic evaluation of the periodontal structure showed both hyperplasia and hypertrophy of the walls of blood vessels supplying the periodontium in the hypertensive and obese-hypertensive animals. The results also indicated that obesity significantly contributed to e severity of periodontal disease. Hypertension alone was not a significant factor. The obese-hypertensive rats showed the most severe periodontal response to local irritation.