A microprocessor temperature-controlled air delivery system for dentinal hypersensitivity testing.

A new microprocessor temperature controlled air delivery system for determining cold and warm temperature thresholds of dentinal hypersensitivity has been designed and built. The temperature range of the unit is -5 degrees to + 85 degrees C. Air is delivered from a typical dental unit air syringe nozzle at a relatively gentle flow rate of 0.2 cu ft/min at operator selected temperatures, with an accuracy of +/- 0.2 degrees C. Within seconds, 1 degree to 5 degrees temperature increments or decrements are accomplished. Larger, i.e., 20 degree increments or decrements, require approximately 15 seconds. The unit can operate from standard 110 V/60 Hz or 230 V/50 Hz outlets and requires a source of compressed air at 60 psig, equivalent to that provided by dental operatory-type air compressors. This report provides a description of the unit, its operation, and data from two clinical studies in which it was used successfully to determine temperature thresholds of dentinal hypersensitivity.

Plaque reduction unaccompanied by gingivitis reduction.

The effects of brushing with three different dentifrices on plaque accumulation and gingival inflammation were studied in 83 subjects. The Turesky modification of the Quigley-Hein plaque index and a modified Löe-Silness gingivitis index were employed. Index scores were obtained in a randomized, double-blind study design, at 0 (baseline), 3-, 6-, and 9-week intervals. ANOVA analyses of results showed no significant differences between any of the three dentifrices used with respect to observed effects. Of interest, however, was the observation that with all three dentifrices reductions in plaque accumulations occurred, at 1% and 5% significance levels, without a corresponding commensurate improvement in the inflammatory status of the associated gingivae (using paired sample t-test analyses). The above results and relevant literature are discussed in support of the thesis that at times, for reasons as yet inexplicable, plaque and gingival inflammation may not be causally related in the manner so commonly observed.