Browse by author
Lookup NU author(s): Dr James Field,
Dr Matthew GermanORCiD,
Professor Paula WaterhouseORCiD
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
Objective When bovine and ovine enamel specimens are substituted for human specimens for erosion and abrasion studies, the assumption is often made that they will behave in the same way. This study aimed to test the null hypothesis that there are no significant differences in surface characteristics of eroded and abraded human, ovine and bovine enamel specimens. Design Twenty enamel slabs were prepared from the labial surface of bovine, human and ovine incisor crowns and embedded in acrylic with a reference layer. Samples were polished with 3 µm aluminium oxide paste and then randomly assigned to one of 4 treatments: i) 30 second immersion at 1% w/v citric acid ii) 4 minute immersion at 1% w/v citric acid iii) 30 second immersion at 6% w/v citric acid and iv) 4 minute immersion at 6% w/v citric acid. Post-erosion, an oscillatory brush was used with a force of 200g for 20 seconds. Roughness average (Ra), bearing parameters (MR1, MR2, Rpk, Rk, Rvk), surface microhardness and scanning electron microscopy (SEM) were used to compare the different tissues at each stage. The maximum height change in the profile was also measured from the acrylic reference layer. One way Analysis of Variance (ANOVA) was used to compare surface characteristics between tissue types. 3-way ANOVA was used to test the individual effects of the variables. Finally, forward stepwise multiple linear regressions were carried out with abraded height change (representing tooth surface loss) as the dependent variable. Results Whilst the eroded surface became generally less rough after the abrasive challenge, there were significant tissue differences for Ra, Rk, Rpk, Rvk and MR1 values. Abraded microhardness was significantly increased compared to baseline eroded values (P < 0.001), with bovine enamel recording the hardest enamel and ovine the softest. Surface loss was also significantly different between tissue types (P < 0.001) with ovine enamel recording the largest amount of surface loss, and bovine the smallest. Typical SEM images of eroded and then subsequently abraded human, ovine and bovine enamel at high magnification show significant differences for each tissue that are consistent with the quantitative data. Conclusions The null hypotheses were rejected; Ovine enamel displayed little correlation with human enamel when subjected to erosive and abrasive challenges. Bovine enamel showed similar trends to human enamel but was consistently harder and more resistant to surface change. Therefore bovine enamel cannot be reliably used interchangeably with human enamel for erosion and abrasion studies.
Author(s): Field JC, German MJ, Waterhouse PJ
Publication type: Conference Proceedings (inc. Abstract)
Publication status: Published
Conference Name: 93rd General Session & Exhibition of the International Association for Dental Research
Year of Conference: 2015
Acceptance date: 09/12/2014
Publisher: The International Association for Dental Research (IADR)