LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 2 of total 2

Search options

  1. Article ; Online: A comparative study of the cutting efficiency of diamond rotary instruments with different grit sizes with a low-speed electric handpiece against zirconia specimens.

    van Aswegen, Ane / Jagathpal, Avish J / Sykes, Leanne M / Schoeman, Herman

    The Journal of prosthetic dentistry

    2023  Volume 131, Issue 1, Page(s) 101.e1–101.e8

    Abstract: Statement of problem: The use of zirconia in dentistry has increased. However, little attention has been given to the difficulty experienced by clinicians when cutting zirconia restorations intraorally. Evidence for which grit size and type of rotary ... ...

    Abstract Statement of problem: The use of zirconia in dentistry has increased. However, little attention has been given to the difficulty experienced by clinicians when cutting zirconia restorations intraorally. Evidence for which grit size and type of rotary instrument is best for cutting zirconia intraorally is lacking.
    Purpose: The purpose of this in vitro study was to identify the most efficient diamond rotary instrument grit size for cutting zirconia intraorally.
    Material and methods: Efficiency was measured by comparing the cutting depth of each rotary instrument into zirconia, analyzing zirconia specimens for surface damage after cutting, and measuring instrument deterioration. Thirty zirconia specimens of the same measurements were used as test specimens and cut with 30 diamond rotary instruments with different grit sizes. An electric handpiece was used with constant force (1.7 N), speed (40 000 rpm), time (1 min), and water flow rate (25 mL/min) to produce comparative data. The mean cutting efficiency values were compared by analysis, and the median values were compared by the nonparametric Kruskal-Wallis test (α=.05). Each test was followed up with pair wise comparisons of the mean or median values if significance was indicated.
    Results: The greatest cutting depth was achieved with a fine-grit instrument with a mean cutting depth of 5.79 mm compared with 4.54 mm for the coarse-grit instrument (P=.032). The greatest damage to zirconia was done by the coarse- and supercoarse-grit instruments (both 33%), with no substrate damage by the superfine-, fine-, and medium-grit instruments. The greatest instrument deterioration was found on the supercoarse rotary instruments (9.05%). With only 3 exceptions, the power calculations were all sufficient and above 83%.
    Conclusions: The fine grit rotary instrument (between 40 and 50 µm) was the most efficient, achieving the greatest cutting depth, with no detectable macroscopic damage to the zirconia and minimal instrument deterioration.
    MeSH term(s) Diamond ; Zirconium ; Surface Properties ; Materials Testing
    Chemical Substances zirconium oxide (S38N85C5G0) ; Diamond (7782-40-3) ; Zirconium (C6V6S92N3C)
    Language English
    Publishing date 2023-11-03
    Publishing country United States
    Document type Journal Article
    ZDB-ID 218157-5
    ISSN 1097-6841 ; 0022-3913
    ISSN (online) 1097-6841
    ISSN 0022-3913
    DOI 10.1016/j.prosdent.2023.10.004
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  2. Article ; Online: Comparison of excess cement around implant crown margins by using 3 extraoral cementation techniques.

    Jagathpal, Avish J / Vally, Zunaid I / Sykes, Leanne M / du Toit, Jonathan

    The Journal of prosthetic dentistry

    2020  Volume 126, Issue 1, Page(s) 95–101

    Abstract: Statement of problem: Extrusion of excess cement into the subgingival area around implant-supported crowns is associated with detrimental inflammatory response, but controlling this excess material remains a challenge.: Purpose: The purpose of this ... ...

    Abstract Statement of problem: Extrusion of excess cement into the subgingival area around implant-supported crowns is associated with detrimental inflammatory response, but controlling this excess material remains a challenge.
    Purpose: The purpose of this in vitro study was to perform a comparative analysis of 3 extraoral cementation techniques to reduce excess extruded cementation material around implant-supported crowns.
    Material and methods: Forty-four internal connection implant replicas were embedded in acrylic resin to form the experimental model. Cementable abutments were tightened onto the implants. Zirconia crowns were luted to each of the cementable abutments by using 1 of 4 techniques: control, pattern resin analog that was 3D-printed, fast-setting polyvinyl siloxane analog, and putty index analog. Extruded excess cement was collected at each luted crown and weighed.
    Results: The mean residual weight of excess cement found in the pattern resin analog technique group was the least (0.087 mg), followed by the polyvinyl siloxane analog technique group (1.678 mg). The putty index analog technique group reported the least reduction of excess extruded cement (7.621 mg). All techniques produced substantially less extruded cement than the control (85.166 mg). In a 1-way analysis of variance, statistically significant differences (P<.001) were found among all the test techniques. Pairwise comparisons also found that all 3 test techniques were statistically different from each other.
    Conclusions: The pattern resin (3D-printed) analog technique produces the least amount of extruded excess cement at an implant-supported crown, limiting detrimental impact on peri-implant tissue health.
    MeSH term(s) Cementation ; Crowns ; Dental Abutments ; Dental Cements ; Dental Implants ; Dental Prosthesis, Implant-Supported
    Chemical Substances Dental Cements ; Dental Implants
    Language English
    Publishing date 2020-07-04
    Publishing country United States
    Document type Journal Article
    ZDB-ID 218157-5
    ISSN 1097-6841 ; 0022-3913
    ISSN (online) 1097-6841
    ISSN 0022-3913
    DOI 10.1016/j.prosdent.2020.04.016
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top