Vickers hardness studies of calcium oxalate monohydrate and brushite urinary stones.

Abstract

PURPOSE:

To measure the hardness of two types of urinary stones: calcium oxalate monohydrate (COM; CaC2O4 . H2O) and dicalcium phosphate dihydrate (brushite; CaHPO4 . 2H2O).

MATERIALS AND METHODS:

The composition of 28 calcium oxalate monohydrate and 22 brushite stones was characterized by infrared spectroscopy (FT-IR). Stone specimens were embedded in crystallographic resin, polished, and subjected to indentation tests using a Vickers tester. The hardness was calculated from measuring the diagonal lengths of the residual indentation on the specimen using the appropriate equation.

RESULTS:

The COM stones showed hardness values ranging from 15.3 to 64.2 HV with a mean of 35.8 +/- 13.3, while brushite stones ranged from 10.1 to 46.1 HV with a mean of 26.5 +/- 15.1. The results of ANOVA showed that there were significant differences (P < 0.05) between the two stone types.

CONCLUSIONS:

Calcium oxalate monohydrate stones exhibited greater hardness than brushite stones when assessed with Vickers studies.

• Authors: N Bouropoulos, D E Mouzakis, G Bithelis, E Liatsikos
• Journal: Journal of endourology (J Endourol) Vol. 20 Issue 1 Pg. 59-63 (Jan 2006) ISSN: 0892-7790 [Print] United States
• PMID: 16426135 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Calcium Phosphates
• Calcium Oxalate
• calcium phosphate, dibasic, dihydrate

Topics

• Calcium Oxalate (analysis)
• Calcium Phosphates (analysis)
• Hardness
• Humans
• In Vitro Techniques
• Microscopy, Electron, Scanning
• Spectroscopy, Fourier Transform Infrared
• Urinary Calculi (chemistry, ultrastructure)