Visualisation and reconstruction in dentistry

Visualisation in the field of dentistry has nor, thus far, reached the same development as other medical fields. Potential applications of visualisation techniques in this area, however, are many, ranging from educational displays to training for delicate procedures. This paper reports on the investigation of techniques for handling three-dimensional models of teeth, aiming at investigation of dental structures. An algorithm was implemented for this purpose, which reconstructs three-dimensional teeth models from two-dimensional contour slices. Results employing various data sets are presented, including the output of VRML models for exploration.

Gastric and small intestinal lesions after partial stomach resection with Billroth II or Roux-en-Y reconstruction in the rat

The evolution and phenotypic expression of mucosal lesions of the gastric stump were investigated in male rats submitted to gastric resection with reconstruction by the Billroth II technique (BII with biliopancreatic reflux, BPR) or by the Roux-en-Y procedure (without BPR). Animals were studied at 24, 36, 54 and 64 weeks after surgery and the phenotypic expression of lesions analysed using routine hematoxylin and eosin staining, immunohistochemical staining for pepsinogen isoenzyme 1 and histochemical procedures for mucins (paradoxical concanavalin A, galactose oxidase Schiff (GOS) and sialidase GOS reactions). BPR was found to be responsible for the formation of adenomatous hyperplasia (AH), increasing in incidence and size with time, since the Roux-en-Y procedure failed to induce the gastric stump lesions observed after BII reconstruction. AHs always occurred in the transition of the gastrojejunal junction, a site offering special conditions for BPR influence, and were classified as gastric (G), intestinal (I) and G+I types according to their phenotypic expression. No pure I type AH was diagnosed at any time point. The G and G+I types developed at approximately equal incidences (i.e., G type 7/17, G+I type 10/17 at the 64th week). It was suggested that both gastric and intestinal mucosal elements were stimulated to proliferate by BPR, with the gastric mucosa tending to demonstrate AH. Intestinal type components of AH were found adjacent to the jejunum and not at the stomach margin, indicating an origin from intestinal mucosa. No metaplasia of the gastric mucosa was observed in any animal after partial gastric resection. In 101 rats submitted to the BII procedure, 5 mucinous adenocarcinomas were eventually diagnosed, mostly located in the subserosa of the gastrojejunal junction. All carcinomas expressed the phenotype of cells of the small intestine. Evidence of malignant transformation within the gastric components of AH was not observed even at the 64th week. In conclusion, all lesions induced by BPR in the rat remnant stomach are benign, and the few true cancers that arise in association are derived from the small intestine.

Finger prosthesis: the art of reconstruction

Hand deformities affect aesthetics function of hand severely compromised and also cause psychological disturbances. This report describes the fabrication of a silicone finger prosthesis for a patient after an accident at work. The finger prosthesis was retained by a vacuum effect on the stump. The silicone material Silastic-MDX 44210 was used to provide function and aesthetics. The finger prosthesis offered psychological, functional and rehabilitative advantages for the patient. Restoring the natural appearance with the prosthesis eliminated the trauma generated by the dysfunction and represented an efficient psychological therapy.

Surgical-allogeneic facial reconstruction: facial transplants

Several factors including cancer, malformations and traumas may cause large facial mutilation. These functional and aesthetic deformities negatively affect the psychological perspectives and quality of life of the mutilated patient. Conventional treatments are prone to fail aesthetically and functionally. The recent introduction of the composite tissue allotransplantation (CTA), which uses transplanted facial tissues of healthy donors to recover the damaged or non-existent facial tissue of mutilated patients, resulted in greater clinical results. Therefore, the present study aims to conduct a literature review on the relevance and effectiveness of facial transplants in mutilated subjects. It was observed that the facial transplants recovered both the aesthetics and function of these patients and consequently improved their quality of life.

Evaluation of the marsh deer stifle joint by imaging studies and gross anatomy

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)