Differential diagnoses of solitary and multiple pigmented lesions of the oral mucosa: Evaluation of 905 specimens submitted to histopathological examination.

BACKGROUND: The aim was to analyze the frequency, clinical and demographic features of solitary and multiple/diffuse oral pigmented lesions submitted to histopathological examination, and to summarize the features that guide the clinical differential diagnosis. METHODS: Clinical and demographic data were retrieved from biopsy records and descriptive statistics were performed. RESULTS: Nine hundred and five (0.51%) oral pigmented lesions were retrieved among 177 356 specimens, being 95.9% solitary and 4.1% multiple/diffuse lesions. Regardless the overlapping clinical presentation, age, site, association with amalgam restoration, and a nodular appearance may help in the clinical differential diagnosis of solitary oral pigmentations. Patient's habits, site, and systemic signs and symptoms are helpful in the clinical differential diagnosis of multiple/diffuse lesions. CONCLUSIONS: Oral pigmented lesions are a rare diagnosis in oral pathology and solitary lesions are more commonly submitted to biopsy. Some key features help in the differential diagnosis, though biopsy can be warranted in doubtful cases.

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.