Comparative Analysis of Cell Proliferation Ratio in Oral Lichen Planus, Epithelial Dysplasia and Oral Squamous Cell Carcinoma

Background: Although oral lichen planus has been classified by the World Health Organization (WHO) as a potentially malignant disorder, such classification is still the target of much controversy. Aim: To evaluate the cell proliferation rate in oral lichen planus, comparing it to the rate observed in epithelial dysplasia and oral squamous cell carcinoma, aiming at indications which might indicate the potential for malignant transformation . Material and Methods: Twenty-four cases of each lesion were submitted to the streptoavidin-biotin and AgNOR technique to evaluate the immunohistochemical expression of PCNA and the mean NORs/nucleus, respectively. Results: Positivity for PCNA was observed in 58.33% of oral lichen planus cases, 83.33% of epithelial dysplasia cases and 91.67% of oral squamous cell carcinoma cases. Chi-squared test showed that the number of positive cases for PCNA was significantly lower in oral lichen planus than in oral squamous cell carcinoma (p0.05) and between the epithelial dysplasia and oral squamous cell carcinoma (p>0.05) was observed. The mean NORs/nucleus in oral lichen planus, epithelial dysplasia and oral squamous cell carcinoma were 1.74±0.32, 2.42±0.62 e 2.41±0.61, respectively. Variance analysis (ANOVA) revealed significant statistical difference between oral lichen planus and the other studied lesions (p<0.05). Conclusion: Oral lichen planus cell proliferation rate was less than in oral epithelial dysplasia and oral squamous cell carcinoma which might explain the lower malignant transformation rate

Necrotizing sialometaplasia as a cause of a non-ulcerated nodule in the hard palate: a case report

<p>Abstract</p> <p>Introduction</p> <p>Necrotizing sialometaplasia is a benign, self-limiting and rare inflammatory disease which, on clinical and histological examination, mimics malignant neoplasms.</p> <p>Case report</p> <p>We report the case of a healthy 25-year-old Caucasian woman with a three-week history of a painless lump on her hard palate. Oral examination revealed a nodule consisting of two lobules on the right side that measured 2.5 cm. Her mucosa was normal in color and a fluctuant area was detected in the posterior region upon palpation. Our patient was submitted to incisional biopsy and histopathological examination. The histological diagnosis was necrotizing sialometaplasia. The lesion had healed spontaneously after 30 days, with observed signs of involution of the nodule.</p> <p>Conclusion</p> <p>Histopathological examination is necessary for the diagnosis of necrotizing sialometaplasia because the clinical features of this condition can mimic other diseases, particularly malignant neoplasms.</p

Effect of low-calcium diet and grind diet on bone turnover of ovariectomized female rats

Objective: The variety of methodologies used to investigate ovariectomized female rats shows different results, which makes a clinical application of these results difficult. The purpose of this work was to evaluate the effect of masticatory effort reduction and of low-calcium diet on maxillary bone turnover of ovariectomized female rats. Study Design: Eighty-four female rats were divided into four groups of 21 animals each as follows: SHAM - sham-operated; OVZ - ovariectomized and fed a standard commercial diet; LCD - fed a low calcium diet, and GCD - fed a grind commercial diet. The inferior first molars were extracted bilaterally 15 days after the ovariectomy, and the animals were euthanized 3, 5 and 8 weeks after ovaries removal. The maxillae were embedded in methylmetacrilate. The results were submitted to analysis of variance. Results: The daily mineral apposition rate lowered with time and was not different between SHAM and OVZ groups. The trabecular bone volume of SHAM and OVZ animals was similar and decreased with time. The GCD animals presented the lowest means and the LCD the highest in comparison to the OVZ group. Conclusion: It was concluded that ovariectomy and a low calcium diet did not cause significant maxillary bone loss in the first molar region, and even in the absence of the antagonist tooth, they did not cause maxillary bone turnover. The grind commercial diet is a good alternative for the study of maxillary bone loss in ovariectomized female rats. © Medicina Oral S. L

Ameloblastic fibro-odontoma : a case report

Ameloblastic fibro-odontoma (AFO) is a rare, benign, slow-growing odontogenic tumor, generally asymptomatic and more prevalent in children and adolescents. We report a case of AFO in the mandible of an eight-yearold Caucasian male patient, and review the literature. Intraoral examination revealed a swelling extending from the deciduous second molar to the retromolar triangle, covered with normal mucosa. A panoramic radiograph showed a large, well-demarcated radiolucency with radiopaque areas. The provisional diagnosis was of AFO, and so an incisional biopsy was performed. Histologically, the lesion was composed of connective tissue resembling the dental papilla, with epithelial strands or islands, as well as denticles and amorphous masses of enamel and dentin consistent with a diagnosis of AFO. Surgical excision and curettage of the lesion were performed. The patient has been monitored for eight years and the lesion has not recurred

Vascular leiomyoma in the oral cavity : report of two cases

Vascular leiomyomas (VL) are benign lesions of perivascular origin. We report two new cases and discuss their clinical, histological and immunohistochemical characteristics, in order to facilitate the diagnosis and treatment of such lesions. The patients, both male, presented asymptomatic nodules located in the bottom of the labial sulcus and buccal mucosa. In the second case, color doppler ultrasonography was performed, which showed no change in blood flow. After excisional biopsies, a limited lesion was observed histologically, with multiple tortuous vessels of varying sizes and calibers, and among them, spindle cells bundles, positive for smooth muscle actin. Oral VLs have clinical features similar to those of other more common lesions, making preoperative diagnosis difficult. Imaging examination, such as color doppler ultrasonography, may help in diagnosis. In general, excisional biopsy is performed, due to the ease of removal of the lesion during surgery. The treatment of choice is the complete excision of the lesion, which has an excellent prognosis and a low rate of recurrence

Intraosseous foreign-body granuloma in the mandible subsequent to a 20-year-old work-related accident

The purpose of this article was to describe the clinical and microscopic features of an intraosseous foreign-body granuloma in the mandible that developed after the traumatic implantation of metal fragments during a work-related accident. A 65-year-old male patient had a severe pain in the body of mandible. Clinical examination showed facial asymmetry and a scar, extending to the left mental region. Intraoral examination revealed a soft mass involving the left alveolar bone with normal appearance of the mucosa surface. Panoramic radiographs showed a radiolucent lesion along the mandible extending from the central incisive to the first molar. Computed tomography revealed an osteolytic mass in the same area. His medical history included a work-related accident twenty years prior to evaluation. During the biopsy an important amount of bright metal-like pieces surrounded by soft tissue were found. A microscopic examination showed a foreign body associated with an aggregation of multinucleated giant cells. The final diagnosis was a foreign body granuloma. Even though foreign-body granulomas in the mandible are rare lesions, dentists should be familiar with their features and include them in the differential diagnosis of tissue masses

Subcutaneous tissue reaction to castor oil bean and calcium hydroxide in rats

Castor oil bean cement (COB) is a new material that has been used as an endodontic sealer, and is a candidate material for direct pulp capping. OBJECTIVE: The purpose of this study was to evaluate the biocompatibility of a new formulation of COB compared to calcium hydroxide cement (CH) and a control group without any material, in the subcutaneous tissue of rats. MATERIAL AND METHODS: The materials were prepared, packed into polyethylene tubes, and implanted in the rat dorsal subcutaneous tissue. Animals were sacrificed at the 7th and 50th days after implantation. A quantitative analysis of inflammatory cells was performed and data were subjected to ANOVA and Tukey's tests at 5% significance level. RESULTS: Comparing the mean number of inflammatory cells between the two experimental groups (COB and CH) and the control group, statistically significant difference (p=0.0001) was observed at 7 and 50 days. There were no significant differences (p=0.111) between tissue reaction to CH (382 inflammatory cells) and COB (330 inflammatory cells) after 7 days. After 50 days, significantly more inflammatory cells (p=0.02) were observed in the CH group (404 inflammatory cells) than in the COB group (177 inflammatory cells). CONCLUSIONS: These results demonstrate that the COB cement induces less inflammatory response within long periods

Porous titanium for biomedical applications : an experimental study on rabbits

Objective: The aim of this study was to carry out an in vivo assessment of bone ingrowth in two different types of porous titanium -the first being completely porous, and the second with a porous surface and dense nucleus, manufactured by powder metallurgy- and to evaluate their mechanical properties. Study design: Ten scaffolds from each group were submitted to metallographic analysis and compression tests. Next, two scaffolds of each type were inserted into 14 rabbits, which were sacrificed 8 weeks after surgery. The samples were submitted for histological examination. Results: Metallographic analysis revealed interconnected pores, and the average interconnected pore diameter was about 360 mm, with 36% total porosity. The totally porous titanium samples and the titanium samples with porous surface and dense nucleus showed an average compressive strength of 16.19 MPa and 69.27 MPa, respectively. After 8 weeks, the animals showed bone ingrowth, even into the most internal pores. Conclusions: The pore morphology was effective in permitting bone ingrowth in both groups. Titanium scaffolds with a porous surface and dense nucleus showed the best mechanical properties and most adequate interface