Rare clear cell odontogenic carcinoma associated with impacted tooth in a young patient: case report and literature review.

Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic tumor. It is characterized by showing, on histopathological examination, clusters of vacuolated and clear tumor cells with epithelial differentiation surrounded by fibrocollagenous stroma and fibroblasts. The present study presents a rare clinical case of mandibular CCOC associated with an impacted tooth in a 26-year-old woman surgically treated with mandibulectomy and reconstruction with iliac crest bone graft. The patient has been followed up for 22 months without signs of recurrence. A search for case report/case series was carried out in the PUBMED database, as well as in the references of relevant previously published literature reviews. Ninety-six publications were identified, totaling 136 distinct cases reported. Female sex was the most affected (63.1%) with 63.3% of cases occurring in patients in the fifth, sixth, or seventh decades of life. The mandible was more affected than the maxilla (74.2%). Association of CCOC with impacted teeth was found in 2.4% of cases, thus rendering it a rare occurrence. The present case report corroborates the results of the survey regarding sex and anatomical location of the tumor; however, it contradicts the findings regarding age predilection. The case described is the fourth known occurrence of tooth impaction associated with the tumor and the first in a female. In conclusion, CCOC should be considered, as well as other malignancies, as a possible diagnosis of maxillary or mandibular intraosseous lesions even in unusual circumstances such as in association with impacted teeth and in young patients.

Mast Cells and Blood Vessels Profile in Oral Carcinogenesis: An Immunohistochemistry Study.

BACKGROUND: The objectives of the present study were to evaluate angiogenesis and mast cell density in oral epithelial dysplasia and oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: This was an observational, retrospective and quantitative study. The samples consisted of 60 tissue specimens from patients with squamous cell carcinoma, epithelial dysplasia and controls (n=20/group). Immunohistochemistry was performed using an anti-tryptase antibody to mast cells and anti-CD31 and anti-CD34 for blood vessels and we count the number of mast cells and determine the percentage of CD31 and CD34 antibody staining (vascular density). RESULTS: The mast cells had lower density in OSCC compared to control and dysplasia (p = 0.009). In angiogenesis, the expression of CD31 showed a higher percentage of blood vessels in OSCC (p < 0.001), however, CD34 showed no difference between groups (p=0.092). The CD31 antibody presented as a high immunostaining in oral mucosa than CD34. CONCLUSIONS: The increased vascularity in squamous cell carcinoma suggests that angiogenesis begins when malignant transformation starts that seems to be inversely associated with the number of mast cells.

Influence of infliximab therapy on bone healing post-dental extraction in rats.

OBJECTIVE: TNF-α, which acts directly on osteoclastogenesis, may modify bone turnover. Thus, the objective of this study was to evaluate the influence of infliximab on extraction socket healing. MATERIAL AND METHODS: Eighty-four Wistar rats were randomized into two groups (infliximab EV 5 mg / kg or saline EV 1 ml / kg) and submitted to lower first molar extraction protocol. The animals were sacrificed 1, 3, 7, 14, 21 and 28 days after surgery. The jaws were subjected to radiographic, histomorphometric, histochemical (picrosirius red) and immunohistochemical (TNF-α, RANKL and OPG) analysis. RESULTS: No differences were observed between the groups in surgical difficulty parameters: mass of teeth, number of root fractures and surgical time. Lower area filling with bone as well as increased amounts of remaining cicatricial tissue were observed in the infliximab group at 14 days (p < 0.001). Lower scores for polymorphonuclear neutrophils were seen at 3 (p < 0.01) and 7 days (p < 0.001), lower mononuclear counts at 7 days (p < 0.01) and lower osteoclast counts at 7 and 14 days (p < 0.01 and p < 0.001, respectively). Additionally, reduced TNF-α, RANKL and OPG immunoreactivity were observed, especially at 7 days (p < 0.05). CONCLUSION: TNF-α inhibitor may alter the bone repair capacity after tooth extraction, especially in the initial repair periods, by lower expression of TNF α, RANKL and OPG. Thus, additional caution may be needed in patients who use this class of medication after dental extraction.

Chronic treatment with zoledronic acid increases inflammatory markers in periodontium of rats.

BACKGROUND: Bisphosphonates (BF) rise proinflammatory markers and irreversibly bind to bone. Chronically, BF can lead to an inflammatory status and can increase the local oxidative stress in periodontium. Therefore, the objective of this study was to evaluate whether the chronic infusion of Zoledronic Acid (ZA) increases inflammatory markers in periodontium of rats. METHODS AND RESULTS: Chronically, infusion therapy was performed with ZA (0.04, 0.2 or 1 mg/kg or saline) by four doses in over a 70-day period to analyze periodontium of the first right inferior molar using histologic, histochemical (toluidine blue), and immunohistochemical (CD68, tumor necrosis factor-α (TNF-α), interleukin-1beta (IL-1ß), inducible nitric oxide synthase (iNOS) and nuclear factor kappa B (NF-kB)) tests. The experiment was replicated (ZA 0.2 mg/kg versus saline) for myeloperoxidase (MPO) assay and dose TNF-α, IL-1ß, malondialdehyde (MDA) and glutathione (GSH) in gingiva of the same tooth. Despite there is no alteration in mast cells (P = .608) and CD68 mononuclear-positive cells (P = .351), in the periodontium of the ZA-treated group, was observed an increase in the presence of inflammatory cells (P = .001) and cytoplasmic immunostaining for TNF-α (P = .003), IL-1b (P = .004), iNOS (P = .008), and NF-kB (P =  .025). Levels of MPO (P < .001), TNF-α (P = .002), IL-1ß (P < .001), and GSH (P = .005) were augmented in gingiva of ZA-treated group but MDA (P = .993) levels and NF-kB nuclear staining (P = .923) were not altered. CONCLUSIONS: Chronic treatment with ZA increase proinflammatory cytokines and the number of inflammatory cells in periodontium of rats and GSH are expressed probably in a compensatory manner.

Avaliação microscópica, estudo histoquímico e análise de propriedades tensiométricas da pele de tilápia do Nilo / Microscopic evaluation, histochemical study and analysis of tensiometric properties of the Nile Tilapia skin

OBJETIVO: Caracterizar a pele de tilápia do Nilo, uma possível fonte de biomaterial para enxertia, a partir de suas características físicas (resistência à tração), histomorfológicas e da tipificação da composição do colágeno. MÉTODOS: Amostras de pele de tilápia do Nilo foram utilizadas e, para os testes de tração (utilizando a máquina de ensaios universais Instron®), as peles foram submetidas à imersão em soluções de glicerol em crescente concentração. Parte das amostras foi fixada em formol neutro a 10%, processada e corada com o uso da hematoxilina e da eosina, para confecção de lâminas e posterior análise histológica e histoquímica. Todas as etapas foram reproduzidas também em pele humana, doada de cirurgias plásticas, para efeito comparativo. RESULTADOS: A morfologia da pele da tilápia mostrou-se semelhante à da pele humana, com derme profunda formada por espessas fibras colágenas organizadas, em disposição paralela/horizontal e transversal/vertical. A pele de tilápia também apresentou maior composição por colágeno tipo I em relação à pele humana (p=0,015). Nos testes de tração, a carga média suportada pela pele de tilápia foi de 43,9±26,2 N, enquanto a extensão à traçao teve valores médios de 4,4±1,045 cm CONCLUSAO: A pele de tilápia possui características microscópicas semelhantes à estrutura morfológica da pele humana e elevada resistência e extensão à tração em quebra, o que suporta sua possível aplicação como biomaterial. A derme desta pele é composta por feixes organizados de fibras de colágeno denso, predominantemente do tipo I, o que traz considerável importância para seu uso clínico.

OBJECTIVE: To characterize the Nile tilapia skin, a possible source of biomaterial for grafting, from their physical (tensile strength) and histomorphological characteristics, and from collagen classification. METHODS: Samples of Nile tilapia skin were used and, for microtensile tests (by Instron® universal testing machine), were subjected to immersion in glycerol solutions of increasing concentration. Part of the samples was fixed in neutral formalin 10%, processed and prepared using routine staining with hematoxylin and eosin into tissue slides, for further histological and histochemical analysis. All steps were also played in human skin, donated by plastic surgeries, for comparative effects. RESULTS: The morphology of Nile tilapia skin presented similarities with human skin, showing the deep dermis formed by thick organized collagen fibers, on parallel/horizontal and transversal/vertical arrangement. The tilapia skin also presented a larger composition of type I collagen, compared with human skin (p=0.015). On traction tests, the load average supported by tilapia skin was 43.9±26.2 N, while the traction extensile had mean values of 4.44±1.045cm. CONCLUSION: The tilapia skin has microscopic characteristics, similar to the morphological structure of human skin, and high resistance and tensile extension at break, which supports its possible application as biomaterial. The dermis of this skin is composed by organized bundles of dense collagen fibers, predominantly type I ones, which brings considerable importance for its clinical use.