Study on color matching of equal volume in dental ceramic prothesis materials / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the color changes on brightness and hue in dental ceramic prothesis materials.</p><p><b>METHODS</b>The different color mark of VINTAGE series was sintered on 15 pieces Ni-Cr alloy denture materials. The sample group and control group was given the sintering of color blending with equivalent volume. The order of color mark was of A1 and A2, A2 and A3, A3 and A4, B1 and B2, B2 and B3, B3 and B4 in sample group, and A1, A2, A3, A3.5, A4, B1, B2, B3 and B4 orderly in control group. The chromatic analysis on samples of VITA had been taken through applying PR 650 spectrum detector and adopted the statistic software of Photo Research and SPSS 12.0 for analysis.</p><p><b>RESULTS</b>The statistical difference (P<0.05) of L*a*b* value was found in the different color mark of the same color serials. A non-linearity relation had been found in the chromatic parameters a*b*. It means the change of color was visible.</p><p><b>CONCLUSION</b>Set A has a bigger grading change of brightness than Set B. The change of red-green is obviously in Set A, as well as yellow-blue in Set B.</p>

Clinical application and processing of separate movable partial denture / 华西口腔医学杂志

<p><b>OBJECTIVE</b>This report is to introduce the processing method of the separate movable partial denture and get an initial clinical evaluation.</p><p><b>METHODS</b>The separate movable partial denture was developed as a kind of special design in utilizing double base plate to separately get support for bearing stress and get the stability of retention.</p><p><b>RESULTS</b>The clinical application indicated that the separate movable partial denture has effective function of common movable partial denture as well as has a good function of natural human teeth protection, especially for those patients with I -II tooth loose.</p><p><b>CONCLUSION</b>The separate movable partial denture is the ideal choice of treatment for those patients who are suffering I - II teeth loose. This type of movable partial denture was considered effectively protect natural human teeth and extend the lifetime of natural tooth long-term and further observation in clinical care on this type of denture is needed.</p>

Study on different thickness and chromatics of various opaques / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the effect existed in the course of adopting different thickness and chromatics of various opaques so that a good methods can be provided for clinical care in prosthodontics.</p><p><b>METHODS</b>A model of using the thin plastic paper to control the ceramic thickness was applied in this test. The data of chromaticity was measured by TC-PIIG auto color difference meter and its results was processed by computer.</p><p><b>RESULTS</b>The value of brightness had an uptrend increase with augment of opaques thickness. Metal base color was opaqued and the basic hue was set. A lower and unstable value, besides a relative stable Y, was measured with the uncompleted opaquing. A stability of hue had been gradually concentrated within a certain range accompanying with the increase of opaquing ceramic thickness. A concentrated hue in the second thickness was found in CARAT ceramic which had high ability of opaque and had a stable hue of ceramic in comparison with other opaques. Among those changes, CARAT's brightness showed a minimal change; a gradual stability of chromatics was presented and was limited with-in a certain range though the augment of opaques.</p><p><b>CONCLUSION</b>The metal color in base could be completely opaqued while opaques thickness reaches a certain range. CARAT is the materials of minimal thickness and has relatively strong capacity for opaques.</p>

Short-term follow-up study of Cercon all-ceramic crowns and bridges / 华西口腔医学杂志

<p><b>OBJECTIVE</b>Cercon all-ceramic system was applied clinically for the first time to make all-ceramic crowns and bridges for the patients. The objective of this study was to evaluate the short-term follow-up results of this new system from both technical and clinical aspects.</p><p><b>METHODS</b>15 units of Cercon all-ceramic crowns and bridges were fabricated and applied to 5 patients, all the cases were followed at 1, 3, 6 and 12 months' periods after cementation of the restorations.</p><p><b>RESULTS</b>Cercon all-ceramic system demonstrate natural and esthetical appearance. No fracture, broken and color change were found.</p><p><b>CONCLUSION</b>The reliability of all-ceramic crowns and bridges made from Cercon system was greatly improved due to the strengthening effects of the zirconia copings and substructures, and the indication of this system can be extended to long span posterior bridges. In addition, the better esthetics compared to PFM technique makes it a comparatively ideal all-ceramic system for crowns and bridges.</p>

The study on color space of the VINTAGE & UNIBOND standard color / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To research the color space of the standard color board, guide the clinic work of color match, and establish an foundation for deeper researching.</p><p><b>METHODS</b>Through taking analysis of reflecting spectrum and spectral tristimulus, each parameter of the color on standard board was found out. The color difference between border upon colors on board was worked out through matching the color parameters. The number of color space between each border upon color on standard color board, divided by deltaE = 1.5, was found.</p><p><b>RESULTS</b>The number of color space between each border upon color was 3-6. The color space was bigger in group B, but smaller in group D. The color space was bigger in high lightness area, but smaller in low lightness area.</p><p><b>CONCLUSION</b>Some color space has been found between standard color borders of VINTAGE and UNIBOND. Color of natural teeth is unable to be completely included into standard color border, especially in clinical care.</p>