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Convergent Polishing: A Simple, Rapid, Full Aperture Polishing Process of High Quality Optical Flats & Spheres
Published on: December 1, 2014
A novel air-polishing powder from natural eggshell
Visaluk Punyawattananon1, Wisarut Prawatvatchara1, Niyom Thamrongananskul1
1Department of Prosthodontics, Faculty of Dentistry, Chulalongkorn University.
Purpose:
This study compares the ability of extrinsic stain removal and surface roughness changes on tooth surfaces after using two different types of dental air polishing powder: Sodium bicarbonate and novel eggshell powder.
Methods:
For the study of extrinsic stain removal, twenty bovine teeth were soaked in coffee for extrinsic stain formation. Group 1 and Group 2 were polished with sodium bicarbonate powder and novel eggshell powder, respectively. The acquired stains of teeth were recorded as baseline, and color changes after cleaning with two different powders were also measured by colorimeter. Sixteen samples from eight human posterior teeth were used for the surface roughness test. Surface roughness values (Sa) of two groups (sodium bicarbonate and novel eggshell powder) were measured by a contact-type profilometer before and after polishing with two types of powders.
Results:
The data showed that the average ΔE* value of the sodium bicarbonate group was higher than that of the novel eggshell powder group (P < 0.05). The average ΔSa value of the sodium bicarbonate group was higher than that of the novel eggshell powder group (P < 0.05).
Conclusion:
Sodium bicarbonate powder showed higher stain removal ability and surface roughness changes than the novel eggshell powder.

