Comparative study of two autogenous graft techniques using piezosurgery for sinus lifting

PURPOSE: Maxillary sinus lifting is a technique, in which, a possible complication is sinus membrane perforation. The aim of this study was to compare two techniques using ultrasound surgery to perform autogenous graft for maxillary sinus lifting. METHODS: Ten rabbits were used in the study, one of them did not undergo surgery. The other nine rabbits had their maxillary sinuses filled with autogenous bone grafts collected from the external skull diploe in particulate form on the right side, and shaved on the left side, both with ultrasonic device. Data on bone density in left and right maxillary sinus, obtained by computed tomography in transverse and longitudinal sections, recorded 90 days after the grafts, were statistically compared. RESULTS: There were no statistically significant differences between the two techniques that used shaved and particulate bone collected by means of ultrasonic device from rabbit skulls. CONCLUSION: Assessment of operative procedures led to the conclusion that piezoelectric ultrasound was shown to be a safe tool in the surgical approach to the maxillary sinus of rabbits, allowing sinus membrane integrity to be maintained during surgical procedures.

An experimental model for the study of craniofacial deformities

PURPOSE: To develop an experimental surgical model in rats for the study of craniofacial abnormalities. METHODS: Full thickness calvarial defects with 10x10-mm and 5x8-mm dimensions were created in 40 male NIS Wistar rats, body weight ranging from 320 to 420 g. The animals were equally divided into two groups. The periosteum was removed and dura mater was left intact. Animals were killed at 8 and 16 weeks postoperatively and cranial tissue samples were taken from the defects for histological analysis. RESULTS: Cranial defects remained open even after 16 weeks postoperatively. CONCLUSION: The experimental model with 5x8-mm defects in the parietal region with the removal of the periosteum and maintenance of the integrity of the dura mater are critical and might be used for the study of cranial bone defects in craniofacial abnormalities.

Rat pinealectomy: a modified direct visual approach

PURPOSE: To report a new, direct visual approach for rat pinealectomy. METHODS: Eighty adult female rats (Rattus norvegicus albinus EPM-1 strain) were weighted and anesthetized intraperitoneally with 15 mg/kg xylazine and 30 mg/kg ketamine. The animal was fastened to a dissection table, an incision was made in the skin and the subcutaneous tissue, bringing the lambda into view. The skullcap was opened with a dental drill, bringing the cerebral hemispheres and the superior sagittal sinus into view. The pineal gland, located under the venous sinus, was removed in a single piece using tweezers. Next, the bone fragment was returned to its place and the surgical layers were sutured. RESULTS: This new technique is easy to be done, avoids bleedings and removes only the pineal gland without damage to the remaining encephalon. In addition it makes possible the achievement of a sham surgery, allowing the pineal gland to remain intact. CONCLUSION: The proposed technique intends to facilitate studies aiming to better understanding the complexity and importance of the pineal gland on reproductive and other body systems.

Origem e dispersão dos Tupiguarani: o que diz a morfologia craniana?

A origem e a dispersão dos povos Tupiguarani têm sido intensamente debatidas entre arqueólogos e linguistas nas últimas cinco décadas. Em resumo, pode-se dizer que a ideia de que esses povos, que ocuparam grande parte do território brasileiro e parte da Bolívia, do Paraguai, do Uruguai e da Argentina, tiveram sua etnogênese na Amazônia e dali partiram para o leste e para o sul, por volta de 2.500 anos antes do presente, é bastante aceita entre os especialistas, embora uma dispersão no sentido oposto, isto é, do sul para o norte, com origem na bacia do Tietê-Paraná, não seja completamente descartada. Entre os arqueólogos que consideram a Amazônia como berço desses povos, alguns acreditam que esse surgimento se deu na Amazônia central. Outros acreditam que a etnogênese Tupiguarani ocorreu no sudoeste da Amazônia, onde hoje se concentra a maior diversidade linguística do tronco Tupi. Neste trabalho, a morfologia de 19 crânios associados à cerâmica Tupiguarani ou etnograficamente classificados como tais foram comparados a várias séries cranianas pré-históricas e etnográficas brasileiras por meio de estatísticas multivariadas. Duas técnicas multivariadas foram empregadas: Análise de Componentes Principais, aplicada sobre os centróides de cada série, e Distâncias de Mahalanobis, aplicadas aos dados individuais. Os resultados obtidos sugerem uma origem amazônica para os povos Tupiguarani, sobretudo pela forte associação encontrada entre crânios Tupi e Guarani do sudeste e do sul brasileiro e dos Tupi do norte do Brasil, com os espécimes provenientes da ilha de Marajó incluídos no estudo.

Estudo das características cefalométricas em adolescentes brasileiros portadores de Padrão Face Longa

OBJETIVO: definir valores cefalométricos esqueléticos e dentários para adolescentes brasileiros com Padrão Face Longa. MÉTODOS: a amostra foi constituída de telerradiografias em norma lateral de 30 pacientes com Face Longa, sendo 17 do sexo feminino e 13 do masculino; e 30 pacientes face Padrão I, 15 do sexo masculino e 15 do feminino, no estágio de dentadura permanente durante a adolescência. As características do Padrão Face Longa foram definidas clinicamente, pela análise facial. As seguintes grandezas cefalométricas foram avaliadas: (1) Comportamento sagital das bases apicais (SNA, SNB, ANB, NAP, Co-A, Co-Gn); (2) Comportamento vertical das bases apicais (SN.PP, SN.PM, ângulo goníaco, AFAT, AFAI, AFAM, AFP, AFATperp, AFAIperp); (3) Comportamento dentoalveolar (1-PP, 6-PP, 1-PM, 6-PM, 1.PP, IMPA); e (4) Proporção entre as alturas faciais (AFAIPerp/AFATPerp, AFAI/AFAT, AFAM/AFAI). RESULTADOS E CONCLUSÕES: o erro vertical na Face Longa concentra-se no terço inferior. A maxila apresenta uma maior altura dentoalveolar e a mandíbula, com morfologia mais vertical, mostra maior rotação no sentido horário. Essas características morfológicas e espaciais acarretam alterações sagitais e verticais no esqueleto e alterações verticais dentoalveolares. No sentido sagital, os ângulos de convexidade facial estão aumentados. No sentido vertical, as alturas faciais anteriores total e inferior estão aumentadas. O componente dentoalveolar está mais longo.

Effects of uterine cervix constriction on Wistar rats

PURPOSE: To verify if uterine cerclage can induce craniosynostosis or any cranial deformity in new born Wistar rats. METHODS: One pregnant female Wistar rat underwent laparotomy on day 18 of gestation and the uterus cervix was closed with a 3-0 nylon suture to avoid delivery, that occurs normally on the 21 day. The suture was released after 48 hours beyond the normal gestation period. The female rat delivered 11 pups. Six surviving rats from the delivery (group A - constrained group). Two rats were born from another mother and in the same age were used as control group (group B - 2 nonconstrained controls) were allowed to grow. They were sacrificed 1.2 years after their birth all the eight animals. Linear measurement, routine histology and computed tomography of the skull were performed at the time of their death to evaluate the cranial asymmetries by mesurements of the anatomical landmarks of the craniofacial skeleton of the rats on the two groups and compared then. RESULTS: We did not observe statistically significant differences in any of the compared measurements (p>0.05) obtained through the morphologic and radiologic methods. Histologic examinations did not reveal any sign of premature fusion or suture imbrications. Critical decrease in longitudinal body size was noticed as the limbs too in all the animals of group A. CONCLUSION: Constriction of uterine cervix leads to fetus suffering, even death for a few animals, associated to small body size, but not to craniosynostosis.