ABSTRACT
Controlled studies of the reproducibility of data from electronic pulp testing instruments are limited and contain few statistical analyses. The reproducibility of these readings is important if the instrument is to be used for determining differences in sensitivity. Twenty human subjects (16 male) were used in this study. One incisor, one premolar, one molar tooth with small or no restorations, and two gingival soft tissue positions from each upper and lower arch of each subject were stimulated with the Analytic Technology vitality scanner. This procedure was repeated twice with a 5-minute rest between each trial, for a total of three trials. Each subject was then seen again after a period of at least 3 days, at which time the trials were repeated. The collected data were grouped by trial, tooth position, and day. Paired t test analysis of both the absolute difference between any two trials on the same day and the average of the absolute differences between corresponding trials on days 1 and 2 showed no statistically significant differences (p greater than 0.05). Accommodation to the stimulus was evaluated by examining differences in the mean values between the three same-day trials. The Analytic Technology vitality scanner was found to be reproducible both for consecutive same-day trials and for corresponding trials on different days. No same-day trends in meter readings were noted.
Subject(s)
Dental Pulp Test/instrumentation , Adult , Dentin Sensitivity/diagnosis , Female , Humans , Male , Regression Analysis , Reproducibility of Results , Time FactorsABSTRACT
The purpose of this study was to examine hysteresis of the masticatory system following brief, voluntary lateral positioning of the mandible. Hysteresis was studied in ten healthy subjects, as a function of both time and distance that the mandible was held laterally off the midline. So that the effects of distance of lateral stretch on hysteresis could be studied, subjects positioned their jaws to the left or right of the midline distances of 2, 4, 6, 8, and 10 mm for ten s. So that the effects of time could be studied, the distance of lateral stretch was held a constant 8 mm for durations of two, four, six, 12, 16, and 20 s. Following each voluntary lateral stretch, subjects relaxed the muscles using EMG biofeedback and allowed the mandible to reposition itself passively. Hysteresis was defined as the difference in the mandibular resting position between pre- and post-stretch recordings. Mean hysteresis effects ranged from 0.7 mm to 1.8 mm. Hysteresis effects were found to increase with both distance and time; after eight s, however, no additional effect of time was noted.
Subject(s)
Mandible/physiology , Masticatory Muscles/physiology , Adult , Analysis of Variance , Biofeedback, Psychology/instrumentation , Electromyography/instrumentation , Female , Humans , Jaw Relation Record , Least-Squares Analysis , Male , Muscle Contraction , Muscle Relaxation , Reflex, Stretch , Time FactorsABSTRACT
A handheld pressure algometer is described for the measurement of pain-pressure thresholds. This instrument has a range of measurement of 0 to 16 N/cm2 and can be modified by changing contact points or springs. Technical specifications, a schematic diagram, application examples, and information concerning construction material availability are provided.