2015 Volume 58 Issue 1 Pages 60-70
Purpose: We have devised a technique for daily clinical practice whereby the treatment site is filmed with an intraoral camera and treatment is performed while viewing the images. This study compared the accuracy of cavity preparation between a method with an intraoral camera and with a mirror.
Materials and methods: The subjects were 24 fourth-year dental students. They received training in cavity preparation of maxillary molars while viewing mirror images. They also received training in holding an intraoral camera with the left hand and filming a maxillary left first molar, and preparing cavities with the right hand while viewing images from the camera. When using the camera, the original images were rotated 180 degrees and right-left reversed so that the direction of hand-piece movement on the monitor was the same as the actual direction. In experiments, the maxillary left first molar was set in a mannequin, and cavity preparation was performed in the 12 o'clock position. The occlusal surface of this artificial tooth was flat and cruciform lines were printed in the center. The subjects were instructed to cut only inside between the cruciform lines with flat cavity floors using a diamond point attached to the turbine hand-piece. Cavity preparation for the first tooth was performed while viewing mirror images, and for the second tooth while viewing images from an intraoral camera. After cavity preparation, the teeth were assessed as to accuracy of outlines and flatness of cavity floors by two instructors with the naked eye. Statistics were analyzed by the chi-square test. Cavity preparation time was also measured and tested with Wilcoxon's signed rank sum test.
Results: Out of 24 subjects, 21 had better outlines with an intraoral camera, while 3 received better outlines with a mirror. Out of 23 subjects, 19 had flatter cavity floors with an intraoral camera, while 4 received flatter floors with a mirror. Statistics indicated that significantly more subjects had better outlines and flatter cavity floors with an intraoral camera than with a mirror. Cavity preparation time was 158 seconds (±79 seconds) with a mirror, and 150 seconds (±52 seconds) with an intraoral camera. They were not significantly different from each other.
Conclusion: Cavity preparation of the maxillary left first molar was performed significantly better while viewing images from an intraoral camera than while viewing mirror images.
