Calcifying epithelial odontogenic tumours: Collaborative study of 32 cases and review of literature.

OBJECTIVES: To analyse the occurrence of calcifying epithelial odontogenic tumours (CEOT) based on biopsy records from different Brazilian geographic regions and to contrast the data with a review of the literature. MATERIALS AND METHODS: A 2-step study was conducted. Step 1 consisted of a collaborative study of biopsies obtained from 1953 to 2017 at six Brazilian oral and maxillofacial pathology centres. Evaluation of 86,268 biopsy records was performed. Demographic and histopathological diagnosis data were assessed. In Step 2, a review of the literature of case reports and cases series of CEOT identified across five electronic databases was conducted. RESULTS: In the collaborative study, 32 cases of CEOT were evaluated. This figure represented 0.03% of the oral and maxillofacial lesions and 1.7% of all odontogenic tumours across the centres. Women in the fourth decade of life were more affected. CEOT occurred more in the mandible than in the maxilla (ratio 1.9:1). The review of the literature showed that Asian individuals were more affected by this neoplasm. CONCLUSIONS: Useful knowledge on the epidemiology, treatment and follow-up of CEOT has been provided. Demographic data and clinical features of the cases presented in this collaborative study were quite similar to those of studies reported worldwide.

A retrospective multicentre study of cystic lesions and odontogenic tumours in older people.

OBJECTIVE: The aim of this study was to investigate the frequency and some characteristics of odontogenic tumours, odontogenic cysts and non-odontogenic cysts in an elderly population (≥60 years). BACKGROUND: Few studies describe the distribution of oral lesions in older people. MATERIALS AND METHODS: A retrospective descriptive cross-sectional study was performed. Biopsy records were obtained from the archives of four Brazilian referral centres between 2000 and 2016. Data such as gender, age, anatomical location, symptomatology and histopathological diagnosis were collected and categorised. Statistical analyses were performed adopting a P-value of ≤.05 and a 95% confidence interval. RESULTS: A total of 7259 biopsy records of elderly participants were analysed; 642 cases were cystic lesions and odontogenic tumours, 491 of which being classified as odontogenic cysts (76.5%), 75 as odontogenic tumours (11.7%) and 76 as non-odontogenic cysts (11.8%). The most frequent lesions in each group were radicular cyst (n = 268), ameloblastoma (n = 51) and salivary duct cyst (n = 21), respectively. Overall, women were more affected (n = 351, mean age: 68 years). Intraosseous lesions were more common in the mandible (n = 342), and soft tissue cysts occurred more in the lip (n = 13). CONCLUSION: Odontogenic cysts were relatively common, whereas odontogenic tumours and non-odontogenic cysts were rarer among the older people studied in the present investigation.

A multicentre study of 268 cases of calcifying odontogenic cysts and a literature review.

OBJECTIVES: To investigate the frequency of calcifying odontogenic cysts (COCs) that have been submitted for microscopic examination from representative geographic regions of Brazil and to compare it with literature data. MATERIALS AND METHODS: A retrospective study was conducted on biopsies obtained from 1953 to 2016 at 10 Brazilian oral and maxillofacial pathology centres. A total of 198,350 biopsy specimens were analysed. Demographic data and histopathological diagnosis were evaluated descriptively and statistically. In addition, a literature review of case series was carried out in four electronic databases. RESULTS: A total of 268 cases of COC were surveyed, representing 0.1% of the oral lesions at the centres studied. Female patients in their second decade of life and the maxilla were more affected. The mean lesion size of symptomatic individuals was larger than that of cases without symptoms (p = 0.026). The literature review showed a higher frequency in Asia and Europe, mainly affecting men in the third decade of life. CONCLUSIONS: COC is a rare lesion. Novel data on the clinicopathological features of 268 cases have been added to the literature. Data regarding gender and age of the Brazilian patients reported herein contrast with findings of case series and retrospective studies reported elsewhere.

Microscopic Evaluation of the Effect of Oral Microbiota on the Development of Bisphosphonate-Related Osteonecrosis of the Jaws in Rats.

OBJECTIVES: Osteonecrosis of the jaws is a side effect associated with the use of bisphosphonates. Using histologic analysis, this study aimed to evaluate the influence of microbial colonies in the development of osteonecrosis in the jaws of rats subjected to nitrogenous and non-nitrogenous bisphosphonates, undergoing surgical procedures. MATERIAL AND METHODS: Thirty-four rats (Rattus norvegicus, Wistar strain) were allocated randomly into three groups: 12 animals treated with zoledronic acid; 12 animals treated with clodronate; and 10 animals treated with saline. Sixty days after the start of treatment, the animals underwent three extractions of the upper right molars. After 120 days of drug administration, the rats were killed. Histologic analysis was performed on specimens stained with hematoxylin and eosin by the technique of manual counting points using Image-Pro Plus software on images of the right hemimaxilla. RESULTS: Osteonecrosis was induced in the test groups. There was no statistically significant association between the presence of microbial colonies and the presence of non-vital bone (Kruskal-Wallis, P > 0.05). CONCLUSIONS: Use of zoledronic acid was associated with non-vital bone and the results suggested that the presence of microbial colonies does not lead to osteonecrosis.

Diabetes mellitus and corticotherapy as risk factors for alendronate-related osteonecrosis of the jaws: a study in Wistar rats.

BACKGROUND: The purpose of this study was to investigate the influence of diabetes and corticotherapy on the development of osteonecrosis of the jaws associated with sodium alendronate. METHODS: Rats were allocated into 4 groups of 11 animals each, representing different treatments: (1) alendronate; (2) alendronate and corticotherapy; (3) alendronate and diabetes; and (4) control. Tooth extractions were performed in all animals, and histological analysis was performed by hematoxylin and eosin staining and immunohistochemistry using anti-bone morphogenetic protein (BMP)-4 and anti-matrix metalloproteinase (MMP)-13 antibodies. RESULTS: On hematoxylin and eosin analysis, proportions of inflammatory infiltrate, microbial colonies, and osteonecrosis were significantly greater in the diabetes group. BMP-4 expression in connective tissue was higher in the corticosteroid group than the alendronate group. There were no significant differences between the other groups. MMP-13 expression did not differ between the groups analyzed. CONCLUSION: Diabetes but not corticotherapy is associated with jaw osteonecrosis in rats undergoing alendronate therapy and subjected to tooth extractions.

Comparative study of the concentration of salivary and blood glucose in type 2 diabetic patients.

The objective of the present study was to comparatively evaluate the concentrations of blood and salivary glucose as well as salivary flow and xerostomia in type 2 diabetic and non-diabetic patients. The mean salivary glucose level in diabetic patients was 14.03 +/-16.76 mg/dl and 6.35 +/- 6.02 mg/dl (P = 0.036) in the control group. The mean capillary blood glucose level in diabetic patients was 213 +/- 88 mg/dl, while that in non-diabetic patients was 99 +/- 14 mg/dl (P = 0.000). The mean value for resting salivary flow was 0.21 +/- 0.16 ml/min in diabetic patients and 0.33 +/- 0.20 ml/min in the control group (P = 0.002). The stimulated salivary flow was lower in the group of diabetic patients, with a mean of 0.63 +/- 0.43 ml/min, whereas the control group showed a mean of 1.20 +/- 0.70 ml/min (P = 0.000). Of the diabetic patients, 45% exhibited hyposalivation, in contrast to 2.5% of the non-diabetic patients (P = 0.000). Xerostomia was reported in 12.5% of diabetic patients and 5% of non-diabetic patients (P = 0.23). We can conclude that salivary glucose concentration was significantly higher in the experimental group and that there was no correlation between salivary and blood glucose concentrations in diabetic patients. The total salivary flow was significantly reduced in diabetic patients and there was no significant difference as to the presence of xerostomia in both groups.