咬合小面の傾斜角度測定装置
1957 年 24 巻 1 号 p. 77-80
詳細
1957 年 24 巻 1 号 p. 77-80
The authors deviced a new type of optical Protoractor, an apparatus for measuring the angle of functional cusp inclination. By the ward of functional cusp inclination the authors mean the slope of small surfaces of occlusal wearing, which harmonizes with mandibular movements.
This apparatus consists of two parts, an optical system and a special protoractor. Through the semitranslucent mirror a parallel light beam is thrown vertically upon specimen, which is attached on the circular stage of protoractor. By the angulation of maximum reflection of light, the angle of cusp inclination can be determined three dimensionally. Very small area even 1 mm2 can be measured easily and accurately with this apparatus.
Average error of measurements is estimated ±0.5° for the angle of inclination and ±2.0° for that of direction.
