Dental Equipment

Articulators are designed to reproduce interocclusal relationships extra-orally. The more accurate instruments required for more complex prosthodontic procedures allow more refined adjustments of displacement characteristics of the condyles. However, accurate setting of these variables is often difficult and time-consuming. The stereographic articulator system develops a fossa moulding that incorporates three-dimensional movement details for each condyle, and thus overcomes the need for fine setting of condylar adjustments. The purpose of this study was to assess the reproducibility of this articulator system.

Since 1992, 330 medical nurses have been trained to provide basic oral health care (including ART restorations and dental extractions) in remote areas of Cambodia. However, a range of barriers prevent dental nurses from providing these services, especially a lack of dental materials and instruments. To increase dental nurse (DN) outputs through the regular provision of dental materials and instruments. To improve cross-infection control procedures through the provision of necessary equipment, supplies and training. Six health centres with active DNs participated; three (experimental) health centres received sufficient supplies of dental instruments and materials for one year, and 3-monthly visits by a dentist from the Ministry of Health. The other three health centres (control) did not. During the project period, the experimental group extractions increased to an average of 119 extractions per quarter (a three-fold increase compared to the baseline), 51 ART restorations, and improve...

Under clinical conditions, the time needed for the proper light curing of luting composites or the multi-incremental buildup of a large restoration with halogen curing units is quite extensive. Due to the development of high power curing devices, such as argon lasers and plasma arc lights and, in order to decrease curing time, halogen and LED devices have developed a high intensity polymerization mode.

Purpose: The purpose of this study was to assess the performance of an intraoral dental colorimeter. Materials and Methods: In vivo repeatability of an intraoral colorimeter was assessed by performing color measurements of 30 individuals' right maxillary central incisor. Three consecutive measurements from each individual were made. In the in vitro part of the study, 25 metal-ceramic and 25 all-ceramic specimens were prepared. Five shades of metal-ceramic and all-ceramic specimens were selected for color determination. A widely recognized in vitro colorimeter was used as the control group for the in vitro performance assessment of the in vivo colorimeter. The color differentiation capability of two colorimeters was compared with the readings obtained from ceramic specimens. E values between shade groups of ceramic specimens were calculated and statistically analyzed with Student's t-test. The repeatability of the intraoral instrument was evaluated statistically with Intraclass correlation coefficient. Results: The in vivo evaluation results showed that the overall repeatability coefficient values of L * , a * , and b * notations of the intraoral colorimeter were "excellent." The color differences ( E) calculated between the colorimeters were significant only between shades A 1 -B 1 for metal-ceramic specimens (p = 0.002); however, from 5 of 10 shade couples of all-ceramic specimens, the color differences obtained from the readings of the in vivo colorimeter were significantly different from that of the in vitro colorimeter (p < 0.001). For all specimens, the differences between E values were within clinically acceptable limits (<3.5). Conclusions: Within the limitations of this study, the intraoral colorimeter exhibited successful in vivo repeatability; however, the color difference detection performance of the device varied depending on the translucency of the specimens.

The aim of this study was to examine the particle length, width, perimeter, and aspect ratio of calcium hydroxide powder using a flow particle image analyzer (FPIA). Five sample groups each with 10mg calcium hydroxide were mixed with 15mL of alcohol and sonicated. Digital images of the particle samples were taken using the FPIA and analyzed with a one-way ANOVA. The overall averages ±S.D. among the five groups for particle length (μm), width (μm), perimeter (μm), and aspect ratio were 2.255±1.994, 1.620±1.464, 6.699±5.598, and 0.737±0.149, respectively. No statistical significance was observed among the groups for all parameters. When the total of 46,818 particles from all five groups were classified into the five length categories of 0.5μm increments, there were significant differences in width, perimeter, and aspect ratio (all p-values<0.0001). In conclusion, calcium hydroxide particles have a size and shape that may allow direct penetration into open dentin tubules.