Radiographic evaluation of the effect of obesity on alveolar bone in rats with ligature-induced periodontal disease.

There is evidence that the lack of metabolic control of obese patients may accelerate periodontitis. The aim of this study was to evaluate radiographically the effect of cafeteria-diet-induced obesity on alveolar bone loss in rats subjected to periodontal disease. Twenty male Wistar rats were randomly divided into four groups: 1) control group, 2) control and ligature group; 3) cafeteria group; and 4) cafeteria and ligature group. The animals were evaluated for obesity and euthanized, and the mandible of each rat was removed to perform a radiographic evaluation of alveolar bone loss and its effect on diet-induced obesity. The results showed greater alveolar bone loss in the mice in Group 4 (P<0.01). Thus, we concluded that obese mice, on average, showed greater radiographic evidence of alveolar bone loss than mice undergoing induction of obesity.

Use of high-voltage cathodic current for pain in experimental nerve compression.

OBJECTIVE: To assess the effect of high-voltage cathodic current on pain from a sciatica experimental model. METHODS: A total of 16 male Wistar rats were submitted to the sciatica experimental model in the right hind paw. They were divided into sham group (GS) and group treated with cathodic current (GP-) for 20 min/daily, for 10 days). The model of sciatic compression was performed with a 4.0-chromic catgut thread tie in four points of the sciatic nerve. Assessment of nociception was performed by measuring the time during which the animal held its hind paw in a guarded position (THHP) and the pressure withdrawal threshold, by use of a digital electronic analgesymeter. Data collection was carried out before the sciatica experimental model (AS1), three days after compression (before, AS2, and after treatment, AS3), and five and 10 days after treatment (AS4 and AS5, respectively). RESULTS: According to the functional disability test, both groups showed an increase in nociception, with no reduction at any assessment time. Submitted to pressure, however, GS showed a reduction in the hind paw withdrawal threshold at all assessment times, while GP- showed a reduction in the hind paw withdrawal threshold only initially - at AS5, the threshold was restored. CONCLUSION: No change in nociception was observed on functional assessment; however, on pressure hind paw withdrawal assessment, the treatment with cathodic current showed to be effective with the summation of therapies.

Swimming training and functional assessment of sciatic nociception in rats.

INTRODUCTION: The protective effect of exercise on individuals with peripheral neuropathy is controversial. OBJECTIVE: To assess the influence of physical training of moderate and progressive intensity on nociception of rats in an experimental sciatica model. MATERIALS AND METHODS: The study assessed 18 rats divided into the following three groups: control group (CG); low-intensity swimming group (LISG); progressive-time swimming group (PTSG). To meet the physical training protocol, the animals were placed in a water tank for six weeks, three alternate days per week. In LISG group, the animals swam ten minutes per session, and, in PTSG group, the animals began swimming for ten minutes, and had a ten-minute increase per week. In CG group, the animals swam less than one minute per day, only to get used to the water environment. After finishing the swimming training, the experimental sciatica model protocol was started with constrictive ligature of the sciatic nerve with chromic catgut. Nociception was assessed using the functional disability test, which measures, in a one-minute interval, the time during which the animal holds its hind paw (THHP) in a guarded position. Assessments were performed preoperatively, and on the third, sixth, and tenth post-operative (PO) days. RESULTS: All groups showed a significant increase in THHP on third, sixth, and tenth PO days, as compared to preoperative values. In CG, no significant change was observed in PO assessments, unlike what happened in LISG and PTSG groups. CONCLUSION: Exercise produced greater hyperalgesia.