Microleakage and bond strength of sealant to primary enamel comparing air abrasion and acid etch techniques

Department of Pediatric Dentistry

St Joseph Hospital

Resident’s Name: Derek Banks Date: March 13, 2009

Article title: Microleakage and bond strength of sealant to primary enamel comparing air abrasion and acid etch techniques

Author(s): L Knobloch, T Meyer, R Kerby, W Johnston

Journal: Pediatric Dentistry

Volume (number): 27:6

Month, Year: 2005

Major topic: Pit and fissure sealants

Minor topic: Technique effectiveness

Type of Article: En vivo study

Main Purpose: Evaluate effectiveness of air abrasion versus acid etch techniques for sealant preparation

Overview of method of research: 40 extracted primary molars were divided into 4 groups - control, acid etch, air abrasion, and air abrasion + acid etch. After proper mounting and isolation, the buccal surface of each tooth was flattened, and sealant material was placed using one of the 4 techniques. Teeth were thermocycled to simulate the oral environment, then tested on an instron machine to determine shear strength of sealant material. Immersion in silver nitrate dye and subsequent measurement of dye penetration was used to determine microleakage.

Findings: Air abrasion is not a substitute for acid etching. Acid etch had bond strength twice as high as air abrasion. Acid etch is the standard for chemomicromechanical preparation of teeth prior to placing sealants. This study shows that air abrading prior to acid etching increases bond strength up to 50%. Much variability was found in the evaluation of microleakage. No strong correlations can be made based on the microleakage data from this study.

Key points/Summary: Air abrasion alone = no good. Acid etch alone = better. Air abrasion + acid etch = best.

Assessment of article: Pretty good. I especially liked the SEM photos of enamel prepared with these methods.