Research on the Application of Kinetic Energy in Pediatric Dentistry

Effects of using rubber dam as a oral soft tissue-protection measure during kinetic instrumentation

Abstract

The use of air at high pressure during KCP instrumentation makes it easy to induce the development of emphysema when accidentally directed towards the oral mucosa. This fact, makes the use of rubber dam imperative while working with KCP.
The aim of this study was to analyze the variables involved in the prevention of emphysema both related to the use of rubber dam and to the Kinetic instrumentation per se such as Al₂O₃ particle's size, air pressure used and operating distance from the rubber dam surface.
A total of ninety rubber dam sheets were used. Four different rubber-sheet thicknesses were employed, dividing the sample into nine groups. After performing the abrasion, the samples were observed using a dissecting microscope to determine the time required to perforate the rubber sheet (perforating time). After this analysis, basic data were obtained supporting the idea of the unavoidable use of the rubber dam.
The following conclusions were obtained:
1. As the thickness of the rubber dam sheet increased, the perforation time became longer. A thickness of the rubber dam of over 0.25 mm seems to increase significantly the perforation time (more than 20 seconds).
2. Eventhough 0.81 was the lowest “r” value found (p<0.01), there was also a positive correlation between the operating distance and perforating time. In addition, the diameter of the scratched surface in the rubber dam increased with the enlargement of the operating distance.
3. A negative relation was found between air pressure and perforating time, i. e., as the air pressure increased the perforating time decreased. An interesting finding, was that with 160 psi, the time required to perforate the sheet was extremely short. This suggests a strong necessity of using a rubber dam while working at high pressure.
4. Comparing the use of 27μm particle and 50μm particle, a statistic significant difference was observed (p<0.01). When using 27μm alumina particle the perforating time was markedly short.
5. The scratch y/o perforation obtained was classified into two main shapes: star and round shaped. Based on these findings it can be concluded the best combination when using a KCP is obtained by employing air pressure below 120 psi, a rubber dam sheet thicker than 0.25 mm (heavy type) and an aluminum-oxide particle size of 50μm. On the other hand, it can be stated that the use of the rubber dam does protect the oral soft tissue against injuries caused by improper use of air abrasion and in this way, the appearance of emphysema and soft tissue lesions decreases.