			Home About us Contact

Impression Procedure (impression + procedure)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Impression pressures against teeth in a partially edentulous model with a mobile tooth: influence of impression tray design

JOURNAL OF ORAL REHABILITATION, Issue 5 2000
Y. Nishi
The purpose of the present study was to examine the effect of custom tray designs on local pressures against teeth during the impression procedure. In a previous study, a partially edentulous simulation model with a mobile tooth was used, and the effect of custom tray designs on the displacement of the mobile tooth was examined during the impression procedure. Based on that study's results, we have assumed that the differences in impression pressures between the labial and the lingual sides of a mobile tooth could either cause or affect displacement. The present study was undertaken to determine the local impression pressures against each side of three anterior teeth, including one mobile tooth, using the same simulation model and the same custom trays as in the previous study. It was found that the local pressures exerted against teeth during the impression procedure were affected by the custom tray designs and varied according to the coronal shape, axis inclination and location of the teeth. [source]

Early load mandibular hybrid prosthesis using the Ohio State University acrylic frame requiring no final impression

AUSTRALIAN DENTAL JOURNAL, Issue 3 2009
I Turkyilmaz
Abstract Background:, Although immediate/early loading protocols for dental implants have presented encouraging outcomes, immediate loading procedures may cause discomfort to the patient and may increase the possibility of damage to the surgical site during the impression procedures. The aim of this study was to describe an alternative technique to fabricate a mandibular hybrid prosthesis in three or four days without making any final impression and to evaluate the outcomes of this technique. Methods:, Seven patients aged 41 to 71 years (mean age, 58 ± 11) were considered for this study. Each patient received five implants for the reconstruction of the edentulous mandible. These implants were placed in the anterior region of an edentulous mandible and restored with a final mandibular hybrid prosthesis in four days using the Ohio State University (OSU) acrylic frame requiring no final impression procedure. The patients were followed up to 19 months after implant placement. Results:, No implants were lost, no technical complications were observed and only minor marginal bone loss was noted after an average 15 months. Conclusions:, This clinical study shows that the OSU acrylic frame, which can easily be customized and accommodates variability in arch form, may be an alternative method to restore any edentulous mandible with an early load mandibular hybrid prosthesis. [source]

Viability of fibroblasts in cell culture after treatment with different chemical retraction agents

JOURNAL OF ORAL REHABILITATION, Issue 1 2002
I. Kopa
Prior to fixed prosthodontic impression procedures, temporary horizontal retraction of the free gingival tissue should be accomplished apically to the preparation finishing line. The mechanical,chemical method using cotton retraction cords of various sizes impregnated with various retraction chemicals is the most commonly employed retraction technique. Most retraction agents have pH values from 0·8 to 0·3, and are therefore hazardous to the cut dentine and periodontal tissues. Sympathomimetic vasoconstrictors introduced recently have a pH of 5·6, and are free of systemic side-effects. The present study using the dye exclusion test, colony forming ability test and colorimetric assay was undertaken to evaluate cytotoxic effects of four chemical retraction agents on cultured V-79 fibroblasts, and the dependence of cytotoxicity on the agent concentration and time of exposure. Original concentrations of retraction agents produced stronger cytotoxic effects than dilutions of 1:1 and 1:10. The most aggressive agent, 25% aluminium chloride, took only 1 min to damage all cell cultures. The proportion of cells damaged after 10 min of exposure to tetrahydrozoline was 60%, which was significantly less compared with other chemicals tested. With the colony forming ability test using retraction agents diluted to 1:10 the greatest number of colonies emerged in samples treated with tetrahydrozoline (statistical significance: P < 0·01). The colorimetric assay showed equal cytotoxic effects for 25% aluminium sulphate and tetrahydrozoline. The colorimetric test used in the study has proved an ergonomic, accurate and reliable test for cytotoxicity determination. [source]