Research Summary abstract
British Dental Journal 196, 31 (2004)
Published online: 10 January 2004 | doi:10.1038/sj.bdj.4810879
Research Summary:
Patients' perception of the roughness of restoratives
Alan Atkinson1
- Patients are very aware of rough restorations.
- Little research has been carried out on the degree to which patients can detect differences in roughness.
- This study shows that previous figures for surface roughness values were much too high.
Abstract
Objective
To determine a threshold of detection value for surface roughness of restorations by patients using their tongue.
Method
Samples of composite resin were finished with differing grades of abrasive. The surface roughness (Ra) was measured and representative scanning electro-micrographs taken. These were compared with labial enamel. Twenty-five volunteers were asked to rank them in order of perceived roughness using the tip of their tongue.
Results
These showed that the 60% of volunteers were able to rank the specimens correctly, and were able to distinguish differences in roughness values from between 0.25 and 0.50 
m. This range encompasses that of natural enamel.
Conclusions
The subjects were able to distinguish lower roughness values than have previously been reported. It is concluded that when finishing restorations the surface should have a maximum roughness 0.50 m if it is not to be detected by the patient.
- Retired Senior Dental Officer Dental Practice Board, Hon Research Fellow Eastman Dental Institute