Alveolar Bone Loss Area Research Articles

Drinking green tea alleviates alveolar bone resorption in ligature-induced periodontitis in mice

ObjectivesIt has been reported that green tea exerts antibacterial, anti-inflammatory, and antioxidant effects. The purpose of the present study was to evaluate the effects of drinking green tea on bone resorption in ligature-induced periodontitis in mice. MethodsSixty C57BL/6 eight-week-old male mice were used. To induce periodontitis, a ligature was placed for 7 days around the upper left second maxillary molar. After ligature removal, the animals were administered different concentrations of green tea (1.5 g/60 mL, 3 g/60 mL, or 6 g/60 mL) or distilled water. At 1 and 2 weeks of administration, the animals were sacrificed and micro-CT images of the maxillae were taken. Next, the depth and area of alveolar bone loss in the buccal and palatal sides were measured. The number of inflammatory cells and osteoclasts in histological sections were counted. ResultsThe result showed ligature-induced alveolar bone loss. Green tea inhibited ligature-induced bone loss in the buccal side in a dose-dependent manner. Histologically, ligature increased the number of inflammatory cells and osteoclasts, but this effect was alleviated by green tea. ConclusionsEvidence from this animal experiment suggested that drinking green tea would be potentially beneficial to reduce alveolar bone loss in ligature-induced periodontitis.

Alveolar bone-loss area localization in periodontitis radiographs based on threshold segmentation with a hybrid feature fused of intensity and the H-value of fractional Brownian motion model

Background and objectivePeriodontitis involves progressive loss of alveolar bone around the teeth. Hence, automatic alveolar bone-loss (ABL) measurement in periapical radiographs can assist dentists in diagnosing such disease. In this paper, we propose an effective method for ABL area localization and denote it as ABLIfBm. MethodABLIfBm is a threshold segmentation method that uses a hybrid feature fused of both intensity and texture measured by the H-value of fractional Brownian motion (fBm) model, where the H-value is the Hurst coefficient in the expectation function of a fBm curve (intensity change) and is directly related to the value of fractal dimension. Adopting leave-one-out cross validation training and testing mechanism, ABLIfBm trains weights for both features using Bayesian classifier and transforms the radiograph image into a feature image obtained from a weighted average of both features. Finally, by Otsu's thresholding, it segments the feature image into normal and bone-loss regions. ResultsExperimental results on 31 periodontitis radiograph images in terms of mean true positive fraction and false positive fraction are about 92.5% and 14.0%, respectively, where the ground truth is provided by a dentist. The results also demonstrate that ABLIfBm outperforms (a) the threshold segmentation method using either feature alone or a weighted average of the same two features but with weights trained differently; (b) a level set segmentation method presented earlier in literature; and (c) segmentation methods based on Bayesian, K-NN, or SVM classifier using the same two features. ConclusionOur results suggest that the proposed method can effectively localize alveolar bone-loss areas in periodontitis radiograph images and hence would be useful for dentists in evaluating degree of bone-loss for periodontitis patients.

Effects of simultaneous nicotine and alcohol use in periodontitis progression in rats: a histomorphometric study.

Objective: The aim of this study was to evaluate the effects of alcohol and nicotine, when used alone or simultaneously, on the alveolar bone loss area resulting from ligature-induced periodontitis in rats. Study design: Forty adult male rats received a cotton ligature in the first lower molar sulcular area, and the animals were randomly assigned to different treatments (n = 10, each group) including daily peritoneal injections of saline solution (group A), submitted to self-administration of alcohol 25% (group B), nicotine solution in concentration 0.19 μl/ml (group C), and nicotine solution in concentration 0.19 μl/ml plus self-administration of alcohol 25% (group D). Five weeks later, the animals were sacrificed, and the samples were routinely processed for semi-serial decalcified sections. Results: Ligated teeth showed more alveolar bone loss than unligated ones (p < 0.05). Unligated teeth showed no significant differences between each other (p > 0.05). Analyses between the ligated teeth showed that the group C (nicotine) or group B (alcohol 25%) each had increasing alveolar bone loss in the furcation area, and the simultaneous combination alcohol and nicotine (group D) intensified these effects (p < 0.05). Conclusion: The results suggest that the simultaneous combination of alcohol and nicotine have a synergistic effect in the progression of periodontitis, evidenced by increased furcation region bone destruction in periodontal disease in rats. Key words:Alveolar bone loss, periodontitis, nicotine, alcohol, rats.

Comparison of two methods for alveolar bone loss measurement in an experimental periodontal disease model in rats

There are many studies that evaluate possible risk factors for periodontal diseases in animals. Most of them have focused only on the biological aspects of disease occurrence; therefore, it has been difficult to compare studies of the different methodological approaches. The aim of the present study was to compare different methods - linear and area - of the evaluation of morphometrical alveolar bone loss. Sixty hemimaxillae, defleshed and stained with 1% methylene blue to delineate the cementoenamel junction and alveolar bone crest, were obtained from a previous study that induced periodontal disease by means of ligatures in two groups of fifteen Wistar rats during 9 weeks. Ligatures were placed around the right upper second molars, and the contra-lateral teeth remained as intra-group controls. Digital photographs were taken from the specimens and submitted to a single, calibrated, blind examiner who performed the morphometrical evaluation of alveolar bone loss using both linear and area methods. Mean values of linear and area measurements were obtained from each side - buccal and palatal - of the specimens. The degree of association between the two methods was determined by Pearson's Correlation Coefficient. An almost perfect association (0.98) was determined between the linear and area evaluations. A mathematical formula was subsequently created to estimate the total area of alveolar bone loss, from linear mean measurements. Both methods were suitable for detecting bone level alterations. The results of the present study allow for the transformation of data and better compilation of results from different studies.

Therapeutic effect of a topical CCR2 antagonist on induced alveolar bone loss in mice

Chemokines are known to regulate leukocyte trafficking, recruitment and infiltration in periodontal diseases. The study objective was to determine the effect of an experimental oral/topical chemokine (C-C motif) receptor 2 (CCR2)-antagonist treatment on alveolar bone loss in a mouse model of Porphyromonas gingivalis-induced periodontitis. Balb/C mice (n = 41) were randomly assigned to four groups. Group 1 was infected by P. gingivalis applied orally/topically for 5 wk. Group 2 was also infected and then treated with vehicle (aqueous methylcellulose) for an additional 4 wk. Group 3 was infected and orally/topically treated with CCR2 antagonist (10 mg/kg). Group 4 served as a noninfected, nontreated control group. Mice received intraperitoneal injections of Alizarin (30 mg/kg) and calcein (20 mg/kg) three times from the last day of infection to determine mineral deposition, reflecting bone dynamics. Mandibles were analysed by morphometry and confocal fluorescence microscopy. Alveolar bone loss was compared among groups using Tukey's test, and bone formation was qualitatively observed. Infected mice showed significantly greater alveolar bone loss than noninfected control animals (group 1 vs. 4, p < 0.01). Vehicle-treated mice (group 2) showed the largest area of alveolar bone loss (p < 0.01), while mice treated with the CCR2 antagonist showed the smallest area of alveolar bone loss and were similar to the control group (group 3 vs. 4, p = 0.14). Qualitative analysis of fluorescent dye uptake indicated increased bone formation in CCR2-antagonist-treated mice, suggesting an improved bone repairing process. The results suggested that treatment with CCR2 antagonist inhibited alveolar bone loss and improved bone formation in this model. These data support further evaluation of CCR2 antagonist as a therapeutic target for the development of new treatment modalities on bacterially induced alveolar bone resorption.

Protective Effects of Follicle-stimulating Hormone Inhibitor on Alveolar Bone Loss Resulting from Experimental Periapical Lesions in Ovariectomized Rats

IntroductionThe direct effect of follicle-stimulating hormone (FSH) on bone resorption has been demonstrated recently. The aim of this study was to evaluate the effect of FSH inhibitor leuprorelin (LE) on alveolar bone loss resulting from experimental periapical lesions in ovariectomized (OVX) rats. MethodsTwenty-seven female rats were randomly assigned into 4 groups and subjected to ovariectomy or sham surgery (1.6 mg/kg body weight LE or vehicle was injected immediately). One week after surgery, the pulp of each rat's bilateral lower first molars was exposed to the oral environment. Three weeks after pulpal exposure, all the animals were killed, and bilateral mandibles were extracted for histologic processing. Radiographic and histologic examination for periapical bone loss area, enzyme histochemical examination for tartrate-resistant acid phosphatase (TRAP), and immunohistochemical examination for FSH receptor (FSHR) were performed. ResultsLE significantly decreased the alveolar bone loss area and osteoclast occurrence compared with non–LE treatment ovariectomized rats (P < .05), and the number of FSHR-positive cells was significantly correlated with alveolar bone loss area (r = 0.796, P < .01). ConclusionsLE has protective effects on alveolar bone loss resulting from experimental periapical lesions in OVX rats.

Reproducibility of a hemi mandible positioning device and a method for measuring alveolar bone loss area in mice

The objective of this study was to determine the reproducibility of a positioning device and a method for measuring the area of alveolar bone loss (ABL) in hemi mandibles of mice. Mucoperiosteal flaps were raised in CF1 Mus domesticus mice (n = 10) on the buccal aspects of the left side of the mandibles. Twenty-one days after surgery, the animals were sacrificed, and the mandibles were resected and stained with 1% toluidine blue. Two positioning devices, one for the buccal and the other for lingual aspect, were fabricated to keep the hemi mandibles in a standard position. The reliabilities of the positioning device and the method for measuring ABL area were analyzed using two series of pictures. The photographs were digitized and ABL measured as the exposed root area. Measurements were performed by two blinded examiners using image analysis software. Intra- and inter-examiner reproducibility of the positioning method ranged from -1.5 to +1.33 mm, while intra- and inter-examiner reproducibility of the measurement technique ranged from -3.37 to 14.70. Our results indicate that, due to the small variation observed in ABL area assessment, the positioning device and method for measuring ABL area represent useful techniques for evaluating ABL in mice.

A Method of Scoring the Area of Alveolar Bone Loss in Experimental Animals

A Method of Scoring the Area of Alveolar Bone Loss in Experimental Animals