Acquired oral syphilis: A multicenter study of 339 patients from South America.

OBJECTIVE: To report the clinicopathologic features of acquired oral syphilis cases in South American countries. MATERIALS AND METHODS: Clinical data were retrospectively collected from the records of 18 oral diagnostic services in Argentina, Brazil, Chile, Colombia, Venezuela, Uruguay, and Peru. Serologies of nontreponemal and treponemal tests were used for diagnosis. RESULTS: The series comprised 339 cases of acquired oral syphilis. Secondary syphilis ranked as the most common stage (86.7%). Lesions were more frequent among males (58.0%) and young adults with a mean age of 33.3 years. Individuals aged 20-29 years were most affected (35.3%). The most commonly involved sites were the tongue (31.6%), lip/labial commissure (25.1%), and hard/soft palate (20.4%). Clinically, acquired oral syphilis usually presented as mucous patches (28.4%), papules (25.7%), and ulcers (18.1%). Skin manifestations occurred in 67.7% of individuals, while lymphadenopathy and fever were observed in 61.3% and 11.6% of all subjects, respectively. Most patients were treated with the benzathine penicillin G antibiotic. CONCLUSION: This report validates the spread of acquired oral syphilis infection among young adults in South America. Our directives include accessible diagnostic tools for proper disease screening, surveillance, and counselling of affected individuals, especially in low- and middle-income countries.

Knowledge of Oral Cancer by a Brazilian Population.

The aim of the present study was to investigate the knowledge about oral cancer in a Brazilian population, including initial clinical signs, causal factors, and the health professional of first choice when suspected of the disease. A total of 2261 participants were interviewed in a cross-sectional study, to investigate associations between sociodemographic descriptive variables and knowledge of oral cancer, risk factors, disease precursor lesions, and health professional of choice for diagnosis. The variables were descriptively analyzed and possible associations investigated considering p values < 0.05. A total of 83.4% of participants reported knowing about oral cancer, and 59.5% reported knowing about potentially malignant lesions; both variables were associated (p < 0.0001). Tobacco was identified as the main risk factor (83.6%), followed by family history (66.2%), and poor oral hygiene (54.5%). Interviewees with higher education level had greater knowledge about cancer (p < 0.0001), and the dentist was the health professional of choice for 43.1% of those who knew about the disease (p = 0.007), with the generalist being the most sought specialist. The population evaluated had a low knowledge of oral cancer given the lack of specific clarifications on etiological factors and risk situations. Health education initiatives are necessary to increase population awareness of potentially malignant oral lesions and improve early diagnosis and recognition of the dentist as a qualified professional for diagnosis of the disease.

Recurrent peripheral ameloblastoma in an elderly patient: A case report.

OBJECTIVE: To report a case of recurrent peripheral ameloblastoma (PA) in an elderly patient. BACKGROUND: PA is a benign tumour that affects soft tissues of gingiva or edentulous alveolar areas, exhibiting histopathological characteristics of ameloblastoma. METHODS: A 79-year-old man showed a nodule in the edentulous right mandibular alveolar ridge diagnosed as recurrent PA. CONCLUSION: Clinicians should consider PA as a differential diagnosis of routine nodular lesions affecting the oral mucosa of geriatric patients.

Anatomic variations and lesions of the mandibular canal detected by cone beam computed tomography.

PURPOSE: The mandibular canal is a significant anatomical structure in implant dentistry, and cone beam computed tomography (CBCT) is an important diagnostic image modality in this field of dentistry. The aim of this study was to evaluate the frequencies of anatomic variations and lesions affecting the mandibular canal in CBCT images of the mandible produced for dental implant planning. METHODS: This cross-sectional study evaluated a sample of 250 CBCT examinations (500 mandibular canals). The inclusion criterion was CBCT examinations of the mandible requested for dental implant planning. The presence of anatomic variations and lesions affecting the mandibular canal was evaluated in the CBCT examinations. Moreover, the buccolingual position of the mandibular canal was evaluated in the molar region and in the ramus region. The CBCT exams were evaluated by one observer. The data were analyzed using descriptive and analytical statistics. The one-way ANOVA test was employed to compare the age between the anatomic variations. A paired t test was used to compare the buccolingual position between the molar region and the ramus region. Differences were considered significant when p values were lower than 0.05. RESULTS: The anatomic variations detected were large-diameter mandibular incisive canal (51.6 %), ramification (12 %), and accessory mental foramen (3.2 %). No difference was observed in the age of the patients between the anatomic variations (p > 0.05). The identified lesions included hypomineralization of the canal walls (20.8 %), idiopathic osteosclerosis (8.8 %), osteolytic lesions (3.2 %), iatrogenic perforation of the mandibular canal (2.8 %), and fibro-osseous lesions (1.6 %). The distance between the mandibular canal and the vestibular cortical bone was higher in the molar region than in the ramus region (p < 0.05). CONCLUSIONS: Anatomic variations and lesions affecting the mandibular canal were common findings in the CBCT images of the mandible produced for dental implant planning. An awareness of these alterations is important for dentistry because some of them might require treatment, change oral surgery planning and difficult inferior alveolar nerve anesthetic block.

Anatomic variations and lesions of the maxillary sinus detected in cone beam computed tomography for dental implants.

OBJECTIVE: To evaluate the presence of anatomic variations and lesions of the maxillary sinus in cone beam computed tomography (CBCT) of the maxilla required for dental implant planning. MATERIAL AND METHODS: This transversal prevalence study evaluated a sample of 500 consecutive CBCT exams. The inclusion criteria were CBCT exams of the maxilla required for dental implant planning. The CBCT exams were independently evaluated by two oral and maxillofacial radiologists who assessed the presence of anatomic variations and lesions of the maxillary sinus. As most of the CBCT exams did not allow the evaluation of the area close to the maxillary sinus roof, anatomic variations that take place at this site were not assessed. RESULTS: The anatomic variations detected were pneumatization (83.2%), antral septa (44.4%), hypoplasia (4.8%), and exostosis (2.6%). The identified lesions were mucosal thickening (≤3 mm in 54.8% and >3 mm in 62.6%), polypoid lesions (21.4%), discontinuity of the sinus floor (17.4%), air-fluid level (4.4%), bone thickening of the maxillary sinus wall (3.8%), antroliths (3.2%), discontinuity of the sinus lateral wall (2.6%), sinus opacification (1.8%), and foreign body (1.6%). CONCLUSION: Anatomic variations and lesions of the maxillary sinus were common findings in CBCT exams of the maxilla required for dental implant planning. As some of these conditions can modify dental implant planning and must require specialized treatment, its recognition is noteworthy in dental practice, and especially in implantology. The amount and significance of the anatomic variations and lesions detected in this study reinforces the importance of computed tomography in preoperative dental implant planning.

IL-10 and IL-10 receptor overexpression in oral giant cell lesions.

OBJECTIVE: Central giant cell lesions (CGCL) and peripheral giant cell lesions (PGCL) occur in the jaws and contain osteoclast-like giant cells and mononuclear cells positive for the macrophage marker CD68. The participation of immune-inflammatory mechanisms has been proposed in the lesions development. As IL-10 is one of the most important anti-inflammatory cytokines and it is also an inhibitory cytokine to macrophage function and bone resorption, the purpose of the present study was to investigate its expression together with its receptor (IL-10Rα) in CGCL and PGCL. STUDY DESIGN: Six fragments of CGCL and seven fragments of PGCL were obtained by surgical excision. Frozen specimens were cut and subjected to immunofluorescence staining using fluorescent-labeled anti-CD68, anti-IL-10, and anti-IL-10Rα monoclonal antibodies. Microscopic analyses were performed and the percentage of positive mononuclear and giant cells for each parameter was obtained. RESULTS: Our results revealed that all giant cells from CGCL and PGCL were CD68+ and IL-10Rα+ and that the majority was also positive for IL-10. More than 50% of the mononuclear cells from both lesions expressed IL-10Rα and the majority of these cells were CD68+ and IL-10+. CONCLUSION: Considering that IL-10 has inhibitory effects on the pathologic processes related to the development of the oral giant cell lesions, the high frequencies of cells producing this cytokine seems contradictory to these lesions growth. Investigation about the production of inflammatory cytokines as well as the IL-10 signaling pathways in oral giant cell lesions is required to elucidate the immunopathology of CGCL and PGCL.

NFATc1 and TNFalpha expression in giant cell lesions of the jaws.

BACKGROUND: Activation mutations of SH3BP2 gene have been demonstrated in cherubism and central giant cell lesion (CGCL). In the present study we first attempted to investigate the SH3BP2 gene in peripheral giant cell lesion (PGCL). The effect of SH3BP2 gene mutations on the transcription of the downstream genes nuclear factor of activated T cells (NFATc1) and the cytokine tumor necrosis factor-alpha (TNF-alpha) was also investigated together with the immunolocalization of NFATc1 protein in a set of cases of PGCL, CGCL and cherubism with and without SH3BP2 mutation. METHOD: Fresh samples of five PGCL, five CGCL and one cherubism cases were included in this study. One of the samples of CGCL presented a somatic heterozygous mutation c.1442A>T in exon 11. The cherubism case showed a heterozygotic substitution c.320C>T in both blood and lesion. These mutations were previously published. All coding and flanking regions of the SH3BP2 gene were sequenced in the cases of PGCL. The real-time polymerase chain reaction (RT-PCR) was performed to analyze the transcription of NFATc1 and TNF-alpha genes. The immunohistochemical analysis of the NFATc1 protein was also performed. RESULTS: No SH3BP2 gene mutation was found in PGCL. The RT-PCR showed increased expression of NFATc1 and decreased transcription of TNF-alpha in all the samples. The immunohistochemical analysis of the NFATc1 protein showed a predominant nuclear staining in the multinucleated giant cells. CONCLUSION: The development of giant cells lesions of the jaws and cherubism are possibly mediated by overexpression of NFAT in the nucleus of the multinucleated cells.

Resinous adhesive systems differentially affect the expression of cytokines by human monocytes stimulated or not with Streptococcus mutans in vitro.

OBJECTIVES: The polymerization of adhesive systems is incomplete and the residual monomers that have been released have a cytotoxic capacity. Some teeth develop into pulp necrosis after composite resin restorations. Considering frequent pulpal inflammation in response to cariogenic bacteria, substances released from the patches could affect the cells of the inflammatory infiltrate and interfere with the mechanisms of defense against microorganisms and protection of pulpal tissue. The aim of this study was to evaluate the effect of substances released by different resinous adhesive systems on cell viability and cytokine expression by human monocytes stimulated in vitro with Streptococcus mutans. DESIGN: Peripheral blood mononuclear cells from 10 healthy subjects were stimulated with S. mutans and then incubated with supernatants obtained from the Single Bond Universal (SBU) or Clearfil SE Bond (CSEB) adhesive systems for eight hours. Staining with Annexin V and 7AAD for analysis of apoptosis were performed and detection of monocytes expressing cytokines IL-1α, IL-6, IL-8, IL-10, IL-12 and TNF-α were performed by flow cytometry. RESULTS: No treatment significantly affected apoptosis in monocytes. SBU supernatant increased the frequency of monocytes expressing IL-8 and decreased the monocytes expressing IL-10. Considering S. mutans-stimulated cells, while SBU increased the frequency of IL-8+ monocytes, CSEB reduced the frequency of IL-6 and TNF-α positive monocytes. CONCLUSIONS: Products released from SBU seem to induce proinflammatory effects on monocytes while those from CSEB show an anti-inflammatory outcome. These effects may interfere in the control of cytokine-mediated immunoinflammatory pulp reactions, both in the presence and absence of stimulation by cariogenic bacteria.

Effect of porous tantalum on the biological response of human peripheral mononuclear cells exposed to Porphyromonas gingivalis.

AIM: To evaluate biological behavior of human peripheral mononuclear cells (PBMC) in contact with porous tantalum (PT) and Porphyromonas gingivalis (Pg). METHODS: Pg was incubated for 8 hours. The groups formed were: PBMC (control), PBMC + PT, PBMC + Pg and PBMC + PT + Pg. Cell viability was evaluated using MTT assay. The morphology and adhesion of PBMC to PT was evaluated using scanning electron microscopy. Expression of interleukin (IL)-10, transforming growth factor (TGF)-ß, matrix metallopeptidase (MMP)-9 and receptor activator of nuclear factor-κΒ ligand (RANKL) was determined by enzyme-linked immunosorbent assay. RESULTS: MTT assay revealed that PT did not interfere in the mitochondrial activity of PBMC (P > .05). Scanning electron microscopy showed the adherence of PBMC to PT. IL-10 levels in PBMC + PT were similar to PBMC and lower than PBMC + Pg. TGF-ß levels in PBMC + PT were higher than PBMC and PBMC + Pg. MMP-9 levels in PBMC + PT were similar to PBMC and lower than PBMC + Pg and PBMC + PT + Pg. RANKL levels in PBMC + PT were lower than in PBMC. CONCLUSION: PT did not affect PBMC viability, allowed cell adhesion, reduced expression of RANKL and enhanced TGF-ß in comparison with the control group.

Composite-derived monomers affect cell viability and cytokine expression in human leukocytes stimulated with Porphyromonas gingivalis.

OBJECTIVES: Dental composites release unreacted resin monomers into the oral environment, even after polymerization. Periodontal cells are, therefore, exposed to substances that potentially elicit the immune inflammatory response. The underlying molecular mechanisms associated with the interaction between resin monomers and human immune cells found in the gingival crevicular fluid are not fully understood yet. This study investigated the ability of bisphenol A-glycidyl methacrylate (BISGMA), urethane dimethacrylate (UDMA) and triethylene glycol dimethacrylate (TEGDMA) to induce apoptosis and cytokine release by human leukocytes stimulated with a periodontal pathogen. METHODOLOGY: Peripheral blood mononuclear cells (PBMC) from 16 healthy individuals were included in this study. To determine the toxicity, the PBMC were incubated for 20 hours, with monomers, for the analysis of cell viability using MTT assay. To evaluate cell death in the populations of monocytes and lymphocytes, they were exposed to sub-lethal doses of each monomer and of heat-inactivated Porphyromonas gingivalis (P. gingivalis) for 5 hours. Secretions of IL-1ß, IL-6, IL-10 and TNF-α were determined by ELISA after 20 hours. RESULTS: UDMA and TEGDMA induced apoptosis after a short-time exposure. Bacterial challenge induced significant production of IL-1ß and TNF-α (p<0.05). TEGDMA reduced the bacterial-induced release of IL-1ß and TNF-α, whereas UDMA reduced IL-1ß release (p<0.05). These monomers did not affect IL-10 and IL-6 secretion. BISGMA did not significantly interfere in cytokine release. CONCLUSIONS: These results show that resin monomers are toxic to PBMC in a dose-dependent manner, and may influence the local immune inflammatory response and tissue damage mechanisms via regulation of bacterial-induced IL-1ß and TNF-α secretion by PBMC.

A novel mutation of the SH3BP2 gene in an aggressive case of cherubism.

Cherubism is an autosomal dominant inherited syndrome characterized by excessive bone degradation of upper and lower jaw and its replacement with large amounts of fibrous tissue, which causes a characteristic facial swelling. A correlation with a mutation in the gene SH3BP2 has been previously demonstrated, but a model for its pathogenesis is not yet available. Here we describe a novel mutation in an aggressive case of cherubism located in the pleckstrin homology domain (PH) of the SH3BP2.

Advanced osteosarcoma of the maxilla: a case report.

Osteosarcomas are primary malignant bone tumours in which mesenchymal cells produce osteoid. It is generally the most common malignant bone neoplasm, although lesions of the jaw are uncommon. Osteosarcoma of the jaw (JOS) presents a lower incidence of metastasis and a better prognosis than osteosarcoma of the long bones. However, patients with JOS can exhibit advanced tumours, mainly when early diagnosis is not performed. This article reports on a case of an advanced osteosarcoma of the maxilla. A 38-year-old woman was referred for evaluation and treatment of recurrent fibrous dysplasia of the facial bones. The patient related that she had been diagnosed with fibrous dysplasia four years earlier and, since the first diagnosis, she was submitted to four surgical interventions, all followed by recurrences. The main clinical findings were redness and swelling of the facial skin, upper lip ulceration, and hard palate swelling. Computed tomography showed a large hyperdense mass in right maxilla extending to right orbit and left maxillary sinus. An incisional biopsy was performed and microscopic examination showed areas of osteoid and chondroid formation surrounded by a cellular stroma. The diagnosis of osteosarcoma was established and the patient was recommended for oncologic treatment. Unfortunately, she died six months after the diagnosis due to uncontrollable local spread.

Assessment of Dental Implant Stability in Areas Previously Submitted to Maxillary Sinus Elevation.

This study aimed to compare the primary and secondary stability, measured by resonance frequency analysis (RFA), in implants of different lengths installed in areas submitted to maxillary sinus lift. Correlation between RFA and implant insertion torque was also assessed. Twenty implants of 9 and 11 mm were inserted in areas submitted to maxillary sinus lift. The insertion torque was measured by the Bien Air motor. Osstell, through RFA, determined the implant stability quotient (ISQ) 2 times: the day of implant installation (T1) and 90 days after implant installation (T2). No differences were observed in the ISQ between T1 and T2 when the 20 implants were grouped, nor when the 9 mm implants were evaluated separately. In contrast, when the 11 mm values were evaluated separately, the ISQ was significantly higher in T2 than in T1 ( P < .05). In T1, 9 mm implants had a higher ISQ than 11 mm ones ( P < .05), whereas in T2, the implants of 11 mm showed a higher ISQ than did the 9 mm implants ( P < .05). There was no difference in insertion torque between 9 and 11 mm implants ( P > .05), nor was there a correlation between ISQ and insertion torque ( P > .05). In conclusion, longer implants (11 mm) presented a significant increase in ISQ values during the healing period when installed in areas previously submitted to maxillary sinus lift. This phenomenon was not observed for shorter implants (9 mm). Finally, no correlation was observed between ISQ and insertion torque.

Use of Surgical Laser for Excision of a Neurofibroma Associated With Neurofibromatosis Type-1.

Introduction: Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder that affects approximately 1/3500 individuals. Various bone manifestations and peripheral nerves neoplastic lesions associated with NF1 are seen in the jaws. Several oral manifestations may occur in this disorder; therefore the dentist's knowledge and multidisciplinary management of these patients are extremely important. Case Presentation: In the present article, we present the use of a high-power surgical laser to excise a neurofibroma in a patient with several intraoral manifestations associated with NF1. Conclusion: The use of diode laser (808 nm) for excision biopsy of tongue nodules showed no thermal damage to the tissue, allowing an adequate histopathological analysis of the neurofibroma.

Peripheral Calcifying Odontogenic Cyst: A rare case report.

The Calcifying Odontogenic Cyst (COC) is a simple cyst lined by ameloblastoma-like epithelium with ghost cells. The peripheral COC is a rare lesion and few reports have been published considering its clinical and histopathological features. This article aimed to report on a case of a peripheral COC, discussing its clinical, imaginological and histopathological features. A 9-year-old male patient presented a 10x5 mm painless nodule in the palatal mucosa of the left central incisor. Panoramic, occlusal and periapical radiographs did not show alterations. A computed tomography exam showed a slight soft tissue swelling located in the palatal mucosa of the left maxillary central incisor. An excisional biopsy was performed. The histopathological analysis showed a cystic lesion adhered to an oral mucosa fragment and lined by an ameloblastoma-like epithelium with ghost cells. The diagnosis of peripheral COC was established and the patient has been disease-free for 5 years. Although rare, peripheral COC is an important lesion that should be considered as a differential diagnosis of gingival hyperplastic lesions. Key words:Calcifying odontogenic cyst, odontogenic tumors, peripheral calcifying odontogenic cyst.

Effects of Bio-Oss® and Cerasorb® dental M on the expression of bone-remodeling mediators in human monocytes.

In contribution to diverse techniques of bone reconstruction involving biomaterials in contemporary dentistry, this study aimed to evaluate the effect of the bone-grafting materials Bio-Oss® and Cerasorb® Dental M on the expression of cytokines associated with bone remodeling by human monocytes in vitro. Bio-Oss® and Cerasorb® Dental M were incubated in separate culture media, and their supernatants were added to mononuclear cells of human peripheral blood, some of which had been stimulated with Porphyromonas gingivalis. The frequency of total monocytes and CD14+ monocytes producing cytokines interleukin 6 (IL-6), IL-8, IL-10, IL-12, and tumor necrosis factor alpha (TNF-α) were determined by flow cytometry. One-way analysis of variance with repeated measures, followed by Tukey's post hoc test, revealed that stimulation with P. gingivalis increased the expression of IL-6 and IL-8 and reduced the expression of TNF-α compared to effects demonstrated in the control group (p < 0.05). Adding biomaterial supernatants did not significantly affect the expression of any cytokine evaluated, however, either in the absence or in the presence of bacterial stimulation. Our data suggest that Bio-Oss® and Cerasorb® Dental M neither stimulate cytokine production in human monocytes nor interfere with mechanisms of cell communication mediated by cytokines evaluated during stimulation with P. gingivalis. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2066-2073, 2017.

Morphological Analysis of Resorbable Collagen Membranes by Scanning Electron Microscopy.

OBJECTIVE: : The composition and morphology of the internal and external surfaces of membranes are important for preventing migration of epithelial and connective cells, and allow the installation of osteogenic cells for bone growth. The objective of this study was to analyze the morphology and composition of three types of commercially available resorbable collagen membranes. METHODS: Three types of collagen membranes, with different compositions and coming from different animals, were used: 1) Dental Surgidry F (bovine collagen type I); 2) Bio-Gide® (porcine collagen type I and III); and 3) OsseoGuard™ (bovine collagen type I). These membranes were analyzed using scanning electron microscopy and energy dispersive spectrometry. RESULTS: The membranes showed distinct superficial architectures, porosities and chemical compositions. The membranes exhibited different surfaces and thicknesses, ranging from 0.32 mm to 0.75 mm. The chemical compositions exhibited a high percentage of niobium (Nb) in the Surgidry and OsseoGuard™ membranes; the Bio-Gide® membrane showed a greater proportion of calcium and aluminum relative to other elements. CONCLUSION: Different types of resorbable collagen membranes exhibit different morphologies and chemical composition, which could lead to differences in the mode and time of resorption of the membranes used for guided tissue regeneration procedures.

Oral Lichen Sclerosus: A Rare Case Report and Review of the Literature.

Lichen sclerosus (LS) is a chronic inflammatory mucocutaneous disease that often affects the anogenital area and causes significant discomfort and morbidity. Oral mucosal lesions in LS are extremely rare and might be associated with genital and/or skin manifestations. As a unique manifestation of LS, oral lesions are even more rare, with only 20 cases reported in English-language literature. In reviewing that literature in this paper, we present the case of a 44-year-old white man who sought dental assistance with a complaint of a white spot on his upper lip. Extraoral clinical examination revealed a slight white macule on the left upper lip vermilion next to the labial commissure. Intraoral examination revealed that the macule was approximately 3.5 × 2.0 cm, extended to the upper left labial mucosa, and presented an ivory-white color. Following an incisional biopsy and microscopy, the lesion was shown to be covered by a stratified squamous epithelium showing hyperkeratosis and atrophy. The superficial lamina propria revealed a well-marked band of subepithelial hyalinization and, below it, a band-like mononuclear inflammatory infiltrate. Sections stained by Verhoeff's technique revealed a scantiness of elastic fibers in the superficial lamina propria. The diagnosis of LS was then established. The patient was referred for dermatologic evaluation, which identified no skin or genital lesions, and no treatment was employed. After 6 years, no significant changes in clinical features were observed. Altogether, this rare case makes an important contribution to knowledge on this uncommon condition.

Prevalence profile of odontogenic cysts and tumors on Brazilian sample after the reclassification of odontogenic keratocyst.

PURPOSE: The aim of this study was to evaluate the impact of the reclassification of odontogenic keratocyst (OKC) as a tumor on the prevalence profile of odontogenic cysts (OCs) and odontogenic tumors (OTs). STUDY DESIGN: Two referral Oral and Maxillofacial Pathology services in Brazil were evaluated. All cases diagnosed as OCs or OTs were selected and classified according to the 1992 WHO-classification (cases before 2005 WHO classification of tumors excluding OKC) and the 2005 WHO classification of tumors, going forward including cases of odontogenic keratocyst tumor (KCOT). The frequency and prevalence of OCs and OTs were compared before and after the reclassification. RESULTS: Among 27,854 oral biopsies, 4920 (17.66%) were OCs and 992 (3.56%) were OTs. The prevalence of OTs before 2005 WHO classification of tumors was 2.04%, while the prevalence after 2005 WHO classification was 11.51% (p < 0.0001). Before 2006, the most frequent tumor diagnosed was odontoma with 194 cases (39.67%), and after 2005 WHO classification of tumors the KCOT was the most frequent with 207 cases (41.07%). CONCLUSIONS: The increase in the prevalence of OTs after 2005 WHO is related to the improvement of pathology services and to the inclusion of KCOT in the OTs group.