Long-term follow-up of a case of multicystic ameloblastoma treated with curettage: case report / Acompanhamento a longo prazo de um caso de ameloblastoma multi-cístico tratado com curetagem: relato de caso

The conventional or multicystic solid ameloblastoma is the most common type with the majority of cases affecting the posterior region of the mandible and occurring between the third and fourth decades of life. The present study aims to report a case of multicystic ameloblastoma in which treatment by means of curettage was chosen and no evidence of recurrence was noted over 7 years of follow-up. Although the literature indicates aggressive surgical therapy as the best form of treatment for multicystic ameloblastoma, factors such as the clinical, radiographic and histopathological aspects of the lesion, patient age, postoperative morbidity, possibilities for aesthetic and functional changes must be evaluated together during treatment planning. In some cases, as in the report presented, conservative therapies such as aggressive curettage of the lesion can be effective in the long term, with no recurrence of the lesion and providing quality of life to the patient

Biomechanical and morphological changes produced by ionizing radiation on bone tissue surrounding dental implant

Objective: This study analyzed the effect of ionizing radiation on bone microarchitecture and biomechanical properties in the bone tissue surrounding a dental implant. Methodology: Twenty rabbits received three dental morse taper junction implants: one in the left tibia and two in the right tibia. The animals were randomized into two groups: the nonirradiated group (control group) and the irradiated group, which received 30 Gy in a single dose 2 weeks after the implant procedure. Four weeks after the implant procedure, the animals were sacrificed, and the implant/bone specimens were used for each experiment. The specimens (n=10) of the right tibia were examined by microcomputed tomography to measure the cortical volume (CtV, mm3), cortical thickness (CtTh, mm) and porosity (CtPo, %). The other specimens (n=10) were examined by dynamic indentation to measure the elastic modulus (E, GPa) and Vickers hardness (VHN, N/mm2) in the bone. The specimens of the left tibia (n=10) were subjected to pull-out tests to calculate the failure load (N), displacement (mm) up to the failure point and interface stiffness (N/mm). In the irradiated group, two measurements were performed: close, at 1 mm surrounding the implant surface, and distant, at 2.5 mm from the external limit of the first measurement. Data were analyzed using one-way ANOVA, Tukey’s test and Student’s t-test (α=0.05). Results: The irradiated bone closer to the implant surface had lower elastic modulus (E), Vickers hardness (VHN), Ct.Th, and Ct.V values and a higher Ct.Po value than the bone distant to the implant (P<0.04). The irradiated bone that was distant from the implant surface had lower E, VHN, and Ct.Th values and a higher Ct.Po value than the nonirradiated bone (P<0.04). The nonirradiated bone had higher failure loads, displacements and stiffness values than the irradiated bone (P<0.02). Conclusion: Ionizing radiation in dental implants resulted in negative effects on the microarchitecture and biomechanical properties of bone tissue, mainly near the surface of the implant

Drilling dimension effects in early stages of osseointegration and implant stability in a canine model

Background: This study histologically evaluated two implant designs: a classic thread design versus another specifically designed for healing chamber formation placed with two drilling protocols. Material and Methods: Forty dental implants (4.1 mm diameter) with two different macrogeometries were inserted in the tibia of 10 Beagle dogs, and maximum insertion torque was recorded. Drilling techniques were: until 3.75 mm (regular-group); and until 4.0 mm diameter (overdrilling-group) for both implant designs. At 2 and 4 weeks, samples were retrieved and processed for histomorphometric analysis. For torque and BIC (bone-to-implant contact) and BAFO (bone area fraction occupied), a general-linear model was employed including instrumentation technique and time in vivo as independent. Results: The insertion torque recorded for each implant design and drilling group significantly decreased as a function of increasing drilling diameter for both implant designs ( p <0.001). No significant differences were de - tected between implant designs for each drilling technique ( p >0.18). A significant increase in BIC was observed from 2 to 4 weeks for both implants placed with the overdrilling technique ( p <0.03) only, but not for those placed in the 3.75 mm drilling sites ( p >0.32). Conclusions: Despite the differences between implant designs and drilling technique an intramembranous-like healing mode with newly formed woven bone prevaile

Effects of titanium surface anodization with CaP incorporation on human osteoblastic response

In this study we investigated whether anodization with calcium phosphate (CaP) incorporation (Vulcano®) enhances growth factors secretion, osteoblast-specific gene expression, and cell viability, when compared to acid etched surfaces (Porous®) and machined surfaces (Screw®) after 3 and 7 days. Results showed significant cell viability for Porous and Vulcano at day 7, when compared with Screw (p=0.005). At the same time point, significant differences regarding runt-related transcription factor 2 (Runx2), alkaline phosphatase (ALP) and bone sialoprotein (BSP) expression were found for all surfaces (p0.05). Although no significant correlation was found for growth factors secretion and Runx2 expression, a significant positive correlation between this gene and ALP/BSP expression showed that their strong association is independent on the type of surface. The incorporation of CaP affected the biological parameters evaluated similar to surfaces just acid etched. The results presented here support the observations that roughness also may play an important role in determining cell response

Concepts in Management of Advanced Craniomaxillofacial Injuries

The authors present a sequencing assessment of patients who were victims of traumatic deformities of the craniomaxillofacial complex. To that end, the authors highlight the eight steps worthy of particular attention, namely (1) clinical history and photographic documentation; (2) clinical assessment; (3) assessment through image and diagnostic exams; (4) planning of the treatment; (5) bases for the three-dimensional reconstruction of the face; (6) reconstruction sequence of multiple facial fractures; (7) support measures; and (8) complications. The proposed assessment sequence allows the oral and maxillofacial surgeon or craniomaxillofacial surgeon to assess the degree of impairment of traumatic deformity, which contributes in a significant way to the decision-making process of the treatment

Melanoma: compreensão das causas, tratamentos e estratégias de prevenção

O melanoma é um câncer de pele que afeta as células produtoras de pigmentos da pele. Apesar de essa doença representar cerca de 1% dos cânceres de pele, ela é a maior causadora de óbitos por câncer de pele. Inicialmente, se apresenta assintomático contribuindo para o diagnóstico tardio e prognóstico a depender do estágio do tumor e da lesão primária. Há diversas formas de tratamento, dependendo do estágio do tumor e da lesão primária. O objetivo deste artigo é compreender o que é o melanoma, as causas, consequências e tratamentos do mesmo. Com o intuito de fornecer conhecimento sobre os riscos e formas de prevenção