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The relation between the occlusal plane and the upper articulator arm as obtained with a quick-mounting facebow
J. Dent. 1990;
167
18: 167
International Section
Abstracts
Editor: W. R. E. Laird
Nagib protetske plohe u odnosu na horizontalu, artikulatora s obraznim lukom za brzu montaiu. (The relation between the occlusal plane and the upper articulator arm as obtained with a quick-mounting facebow.) CelebiC A., Kre&mir K., ValentibPeruzoviC M. et a/. (1989) Acra Sromarol. Croat. 23, 137-l 43. The angle between the Frankfort and occlusal planes was measured as the basis of a simple method of estimating the latter from casts mounted on an articulator. Facebow registrations were taken of 30 Caucasian dentate subjects. The respective casts were mounted in a SAM-2 articulator, with the horizontal arm of a quick-mounting facebow parallel to the upper articulator member. The occlusal plane was determined by drawing a line between the midpoint of the mandibular incisors and the highest point of the mandibular molar curve. This was transferred to the maxillan/ cast by means of calibrated paper. The angle between this plane and the upper articulator arm was then measured with a precision protractor. The mean angle between the occlusal and Frankfort planes was 9.42” f 4.7 O,which is comparable to that for other Caucasian groups. When correctly mounted in a suitable articulator, the approximate position of the occlusal plane can be esrimared at an angle of 9.5 o to the upper articulator arm. (28 references) M. J. Shapiro
Establishment of a composite resin inlay technique Part 2. Degradation of composite resins for inlay under alkaline conditions. Hosoda H., Yamada T. and Nitta Y. (1989) Jap. J. Consen/. Dent. 32, 628-638. The degradation process of four composite resins for inlay use was observed under alkaline conditions in 0.1 N NaOH solution at 60X, focusing both on the topographic changes of polished resin surfaces and on the structural changes in the subsurface damage layer of resin. Hybrid type SR-lsosit resin (Ivoclar, Schann, Liechtenstein) showed swelling of matrix resin and small depressions on the polished surfaces. Brilliant D. I. (Coltene, Switzerland), Clearfil CR Inlay (Kuraray, Japan) and IC-3 (Tokuyama Soda, Japan) resins of semihybrid structure showed small gaps between filler particles and matrix resin and many depressions which might be due to filler dissolution or exfoliation on the polished surfaces. The structural changes in the subsurface damaged layer of resin generally showed crack formation between filler particles and matrix resin, particle dissolution and exfoliation of filler particles, and also swelling of matrix resin, which was observed in varying degrees depending 0 1990 Butterworth-Heinemann 0300-5712/90/030167-01
Ltd.
upon the individual resin nature. Degradation of the resins for inlay use proved to be much smaller than that of the restorative composite resins. The experimental composite for inlay, IC-3, revealed the least degradation among the resins tested. (7 references) H. Hisamitsu
Sti)ranf&lligkeit frequenzadaptiver Herzschrittmacher bei zahn&ztlichen BehandlungsmaBnahmen. (Susceptibility of frequency adapted cardiac pacemakers to dental treatment.) Rahn FL, Zegelmann M., Brief I. et a/. (1989) Drsch. Zahnbrzrl. Z. 44,244-247. Two rate-responsive pacemakers (Activitrax and Sensolog) were tested in order to determine to what extent their function can be affected by dental treatment. Inhibition of the pacemaker occurred by switching the electrical dental appliance on and off, or by moving it back and forth. In most cases, inhibition was only evident when the distance between the pacemaker and the electrical appliance was less than 10 cm. The electrotom proved to be the most potent source of disturbance, as the function of the pacemaker was totally inhibited when it was switched on and off with a frequency of l-2 Hz, even at a distance of 2.8 m. During dental treatment-especially osreoromies-vibrations are transferred to the parienr which can cause an increase in the rare of rhe pacemaker. (9 references) Author’s abstract (selected by W. Kullmann)
Rasterelektronenmikroskopische Untersuchung der Wurzelkanalaufbereitung mit Ultraschall. (SEM studies on root canal preparation using ultrasound.) Beer R. and GBngler P. (1989) Drsch. ZahnBrzrI. Z. 44, 334-339. The rbot canals of 35 extracted mandibular incisors were instrumented with an ultrasonic system alone or in combination with hand instruments. Hand instrumentation was compared with ultrasonic instrumentation. Following instrumentation the teeth were prepared for SEM examination. Hand insrrumenrarion using reamers was superior to ultrasonic dhbridemenr. After initial preparation and final shaping wirh hand instruments, the ultrasonic device shows good efficiency in cleaning straight root canals. (14 references) Author’s abstract (selected by W. Kullmann)
167
18: 167
International Section
Abstracts
Editor: W. R. E. Laird
Nagib protetske plohe u odnosu na horizontalu, artikulatora s obraznim lukom za brzu montaiu. (The relation between the occlusal plane and the upper articulator arm as obtained with a quick-mounting facebow.) CelebiC A., Kre&mir K., ValentibPeruzoviC M. et a/. (1989) Acra Sromarol. Croat. 23, 137-l 43. The angle between the Frankfort and occlusal planes was measured as the basis of a simple method of estimating the latter from casts mounted on an articulator. Facebow registrations were taken of 30 Caucasian dentate subjects. The respective casts were mounted in a SAM-2 articulator, with the horizontal arm of a quick-mounting facebow parallel to the upper articulator member. The occlusal plane was determined by drawing a line between the midpoint of the mandibular incisors and the highest point of the mandibular molar curve. This was transferred to the maxillan/ cast by means of calibrated paper. The angle between this plane and the upper articulator arm was then measured with a precision protractor. The mean angle between the occlusal and Frankfort planes was 9.42” f 4.7 O,which is comparable to that for other Caucasian groups. When correctly mounted in a suitable articulator, the approximate position of the occlusal plane can be esrimared at an angle of 9.5 o to the upper articulator arm. (28 references) M. J. Shapiro
Establishment of a composite resin inlay technique Part 2. Degradation of composite resins for inlay under alkaline conditions. Hosoda H., Yamada T. and Nitta Y. (1989) Jap. J. Consen/. Dent. 32, 628-638. The degradation process of four composite resins for inlay use was observed under alkaline conditions in 0.1 N NaOH solution at 60X, focusing both on the topographic changes of polished resin surfaces and on the structural changes in the subsurface damage layer of resin. Hybrid type SR-lsosit resin (Ivoclar, Schann, Liechtenstein) showed swelling of matrix resin and small depressions on the polished surfaces. Brilliant D. I. (Coltene, Switzerland), Clearfil CR Inlay (Kuraray, Japan) and IC-3 (Tokuyama Soda, Japan) resins of semihybrid structure showed small gaps between filler particles and matrix resin and many depressions which might be due to filler dissolution or exfoliation on the polished surfaces. The structural changes in the subsurface damaged layer of resin generally showed crack formation between filler particles and matrix resin, particle dissolution and exfoliation of filler particles, and also swelling of matrix resin, which was observed in varying degrees depending 0 1990 Butterworth-Heinemann 0300-5712/90/030167-01
Ltd.
upon the individual resin nature. Degradation of the resins for inlay use proved to be much smaller than that of the restorative composite resins. The experimental composite for inlay, IC-3, revealed the least degradation among the resins tested. (7 references) H. Hisamitsu
Sti)ranf&lligkeit frequenzadaptiver Herzschrittmacher bei zahn&ztlichen BehandlungsmaBnahmen. (Susceptibility of frequency adapted cardiac pacemakers to dental treatment.) Rahn FL, Zegelmann M., Brief I. et a/. (1989) Drsch. Zahnbrzrl. Z. 44,244-247. Two rate-responsive pacemakers (Activitrax and Sensolog) were tested in order to determine to what extent their function can be affected by dental treatment. Inhibition of the pacemaker occurred by switching the electrical dental appliance on and off, or by moving it back and forth. In most cases, inhibition was only evident when the distance between the pacemaker and the electrical appliance was less than 10 cm. The electrotom proved to be the most potent source of disturbance, as the function of the pacemaker was totally inhibited when it was switched on and off with a frequency of l-2 Hz, even at a distance of 2.8 m. During dental treatment-especially osreoromies-vibrations are transferred to the parienr which can cause an increase in the rare of rhe pacemaker. (9 references) Author’s abstract (selected by W. Kullmann)
Rasterelektronenmikroskopische Untersuchung der Wurzelkanalaufbereitung mit Ultraschall. (SEM studies on root canal preparation using ultrasound.) Beer R. and GBngler P. (1989) Drsch. ZahnBrzrI. Z. 44, 334-339. The rbot canals of 35 extracted mandibular incisors were instrumented with an ultrasonic system alone or in combination with hand instruments. Hand instrumentation was compared with ultrasonic instrumentation. Following instrumentation the teeth were prepared for SEM examination. Hand insrrumenrarion using reamers was superior to ultrasonic dhbridemenr. After initial preparation and final shaping wirh hand instruments, the ultrasonic device shows good efficiency in cleaning straight root canals. (14 references) Author’s abstract (selected by W. Kullmann)