The quantification of surface roughness on root caries using Noncontact Optical Profilometry—An in vitro study

Abstract

Purpose: The aim of this study was to quantify surface roughness of carious dentine using noncontact optical profilometry (NCOP) in vitro. Methods: A total of 20 extracted teeth with root caries were examined according to clinical assessment criteria. NCOP (Proscan 2000, Scantron, Taunton, UK) was used to carry out the surface roughness measurements in vitro. Selection of sampling rate measurements were subsequently performed. Results: Results showed that the surface roughness (Ra) values were most accurately obtained at a sampling rate of 30 Hz. All lesions had rough texture, with cavitation ranging from 0.5 to 4 mm. Most lesions were leathery, whilst remaining few were soft. There was a significant difference in surface roughness between the carious and sound dentine (p < 0.05). Pearson’s correlation coefficient tests failed to show any significant linear correlation between surface roughness measurements and cavitation (r 0.39; p > 0.05) whilst there was a significant correlation between the hardness and surface roughness (r 0.47, p = 0.04). There was an inverse relationship trend between surface roughness measurements and severity of root caries. Conclusions: There are limitations due to the sophisticated layout of collage network within the root carious dentine especially cavitated lesions. The NCOP could be considered for the quantification of surface roughness on noncavitated carious dentine in a laboratory setting. Clinical significance: The effect of different oral health care products on root caries using the NCOP without causing any potential damage to the noncavitated root surface could be assessed prior to the large-scale clinical studies.