Scanning electron microscopic study of air abrasion effects on human dentine

Authors:

ABSTRACT

Aim

Mechanical Surface Micro-Abrasion (MSM) is a technique of cavity preparation and surface treatment. By means of a
precise air-powder jet it cleans and widens pits and fissures before sealing, in order to create micro-retention on tooth surface and to
prepare small therapeutic cavities. It is particularly indicated in children's therapy. The aim of this study is to verify (by SEM) the
existence of a relationship between working time and distance and both macroscopic and ultrastructural aspects of the treated surfaces
following cavity preparation by MSM.

Methods

This experimental study was carried out in vitro using a Micro-
Abrasion system on 60 human third mandibular molars. Before SEM observation the surfaces were divided in five groups, each with a
different working time and distance. All specimens were observed by SEM at several magnifications.

Results

After a treatment of 5
sec at a distance of 2 mm a small preparation could be noticed with a circular section of 0.5 mm of diameter. With a working time of 15
sec, and a working distance of 2 mm, a cavity preparation on dentinal tissue was obtained. With a working distance of 15 mm, even for
a relatively long time of treatment, such as 30 sec, no preparation was noticed but only a sandblasted surface of a circular section with a
diameter of 3.5 mm. With different time of application the authors noticed different microscopic aspects.

Conclusion

The authors
realised that the macroscopic size and shape of cavities is connected to working distance, while working time is important to determine
the depth of preparation and ultrastructural aspect. SEM analysis of dentin surface shows how different parameters determine
macroscopic and ultrastructural aspects. It can help to standardise a protocol to follow according to the desired treatment.

PLUMX METRICS