Immunoexpression of SOX-2 in oral leukoplakia.

OBJECTIVE: This study was conducted to correlate and compare the immunoexpression of sex-determining region Y-box 2 (SOX-2) in oral leukoplakia (OL) lesions with that in normal buccal mucosa (control). MATERIALS AND METHODS: In this observational study, OL with low-risk (n = 34) and high-risk (n = 33) dysplasia and control samples (n = 25) were subjected to immunohistochemical analysis for SOX-2. In the epithelium, SOX-2 positive and negative cells, as well as semiautomatic segmentation of the immunopositive nuclear area were counted. Statistical tests included chi-square, one-way analysis of variance, Tukey, and Games-Howell. The level of significance was 5%. RESULTS: Groups with OL lesions (low and high-risk) showed higher mean numbers of SOX-2 positive cells (63.47 ± 25.70 and 68.18 ± 21.17) compared to the control group (45.85 ± 27.38) (p = 0.00). Groups with OL lesions (low and high-risk) exhibited higher mean positive nuclear area (0.24 ± 0.47 and 1.09 ± 2.06) compared to the control group (0.00 ± 0.01) (p = 0.01). CONCLUSION: Oral leukoplakia lesions showed a higher expression of SOX-2, suggesting its contribution to the pathogenesis of OL.

Effect of the Chronic Use of Lithium Carbonate on Induced Tooth Movement in Wistar Rats.

Patients who seek dental treatment may have bipolar disorder, and lithium carbonate (LC) is the drug of choice used in the treatment of this disorder. Taking into consideration the controversial results found in the literature, and the possible influence of LC on induced tooth movement, the objective was to evaluate tooth movement induced in rats after administration of lithium carbonate. One hundred and ninety-two rats were divided into 3 groups. In the L group, the animals received daily 60mg/kg of LC, they were not subjected to orthodontic movement, and they were euthanized after 33, 37, 44 or 51 days. In the LM group, the LC was administered for 30 days and during the subsequent 3, 7, 14 and 21 days, corresponding to the period of induced tooth movement, and they received a spring that produced a 30cN force. In the SM group, saline solution was applied. Measurements were made of tooth displacement, the numbers of osteoclasts and serum lithium phosphate (PO4), alkaline phosphatase (ALP) and creatinine levels. The tooth displacement was lower in the LM group compared to the SM group at 44 days. A tendency toward reduction in the number of osteoclasts was observed in the LM group compared to the SM group at 44 days. The average lithium were higher in the L and LM groups compared to the SM group. The opposite was observed for the PO4 group. A higher value for the ALP was found in the L group. The average creatinine level was lower in the LM group. LC inhibited tooth movement for 14 days, possibly due to the reduction in the number of osteoclasts.