Evaluation of four elastomeric interocclusal recording materials

Background: The fabrication of dental prosthesis requires the transfer of interocclusal records from patient's mouth to semiadjustable articulators using different kinds of recording media. Any inaccuracy in these interocclusal records leads to occlusal errors in the final prosthesis. This study was conducted to evaluate the dimensional changes occurring in the interocclusal recording material over a given period of time and the material's resistance to compression during the cast mounting on the articulator.     

An anatomical study of the facial artery

The anatomical variations encountered in the dissection of 50 facial arteries in 25 adult preserved cadavers are presented. The facial artery was symmetrical in 17 of 25 (68%) of the dissections. The facial artery terminated as an angular facial artery in 34 (68%), a lateral nasal vessel in 13 (26%), and a superior labial vessel in 2 (4%); in 1 (2%) the facial artery terminated at the alar base. A longer course was identified in 5 (10%) facial arteries. The use of nasolabial flap (skin, full-thickness, and oral mucosa) raised as an island flap based on the facial artery or one its branches is discussed.     

A new method of stabilizing the chest wall following major chest wall resection

Summary Prosthetic materials, such as metals, marlex mesh and methyl methacrylate have been used for stabilization of the chest wall after resection of large areas of rib cage. Such materials are contraindicated in an infected area. A new method of providing a stable chest wall using autogenous tissue is presented.     

A new technique for the division of syndactyly

Summary This paper describes a new technique for the division of syndactyly. The commissure is reconstructed by a dorsal trilobed flap and a zig zag incision which produces triangular flaps for the side of the digits. This technique does not require use of a skin graft. Seventeen syndactylies in fourteen children, nine incomplete (six congenital and three secondary to burn) and eight complete syndactylies were treated by this technique. The results after a maximum of twelve months follow-up and the advantages of the technique are discussed.[/ab]     

A feasibility study to investigate the use of thin-plate splines to account for prostate deformation

Image registration is an important step in the radiotherapy treatment planning process. It provides a method of fusing different types of diagnostic imaging information. One such application is to combine magnetic resonance spectroscopic images (MRSI) of the prostate with anatomical MRI and/or computed tomography images that are routinely used in the radiation treatment planning of prostate cancer. MRSI provides in vivo information related to the underlying metabolic activity of tissues, and can be related to the presence of cancer. However, the inflated endorectal coil required during MRS imaging poses a potential problem by deforming the prostate when it is filled with approximately 100 cm3 of air during image acquisition. This pushes the prostate superiorly/anteriorly, deforming the prostate and consequently the spectroscopic imaging data in a nonlinear manner. In this application, the coil-deformed MRS images are warped back to a non-deformed state, using a single data set. A nonlinear warping algorithm is presented to achieve this. Results indicate that the algorithm attains an accuracy of 97% (4 cm3 difference) when reproducing the total prostate volume compared to a Radiation Oncologist defined prostate volume. This difference is slightly smaller than the measured intra-operator variance of +/-1.5 cm3 (deflated coil) and the measured algorithm variance of +/-1.0 cm3. Additionally, intraprostatic nodules were used to assess the accuracy of the warping algorithm in regions inside the prostate. While choosing anatomical tie points along the external prostate surface, analysis of the nodules revealed the algorithm accuracy reduced to 63-93%.