Abstract
The purpose of this study was to investigate the influence of cleaning and polishing pretreatments for the effect of acid etching on the primary enamel smooth surfaces.
Fifty-nine labial surfaces of the extracted or exfoliated caries-free primary anterior teeth were used.
The cleaning and polishing pretreatments used in this study were: application of 10 % NaOCl, polished with a brush cone (Hawe-Neos-Dental Co. ) or a polishing brush (Sato Dental Material Co. ) at a low speed (600-6000 r. p. m. ), polishing with a brush cone and various polishing pastes, cleaning with an air polisher Prophy-Jet (Dentsply Co. ) or Quick-Jet (Dentscraft Co. ) with NaHCO3powder and water. The polishing pastes used in this study were Neo-Polishing-Paste (Neo Dental Chemical Products Co. ), pumice slurry (Tokyo Dental College prescription), tooth paste (Lion Co. ) and CCS Prophy-Pastes (Inoue Marketing Co. )Etchant used in this study was 40 % phosphoric acid gel, and after one minute etching, all specimens were washed with an air water spray for 30 seconds.
The following observations were obtained using the SEM.
1. Tooth to tooth difference of the etching effects and patterns was observed under the same cleaning and polishing methods.
2. Various etching effects and patterns on the same enamel surface were observed.
3. The most common etching patterns were poorly structured etching patterns (84.7%) and peripheral etching patterns (81.4%).
4. It was likely that materials such as organic films and cuticles would remain on the etched enamel pretreated with the low efficacy polishing and cleaning methods.
5. However it was considered that tooth to tooth difference influenced the etching effects more than the cleaning and polishing pretereatments.
