Effect of buccal administration of a lactose-containing nitroglycerin tablet (Suscard) on plaque pH

The aim of this study was to monitor pH in 2-day-old dental plaque after administration of a long-acting, lactose-containing nitroglycerin tablet (Suscard). The tablet was placed under the lip of the maxilla. This was done both in two older subjects suffering from heart problems and in 10 younger, healthy subjects. In the latter group, a sucrose-containing lozenge was used as a control. The influence of a 5-wk period of daily use of Suscard (in the two elderly subjects) and the effect of normal oral hygiene procedures (in the 10 younger subjects) on the pH response was also studied. Plaque pH was measured in situ up to 1 h, at five different approximal sites in the front region of the maxilla by the micro-touch method. The Suscard tablet resulted in a fall in plaque pH in both groups when teeth had not been brushed for 2 days. The lowest pH was recorded at the sites close to where the tablet had been placed. The most attenuated pH drop was found in the two older subjects, who showed a mean minimum pH of 5.7, as compared with 6.2 for the younger subjects. No further increase in the pH fall from Suscard was seen after the 5-wk period in the two patients with heart problems. In the 10 younger healthy subjects, the most pronounced pH decrease was registered after administration of the sucrose-containing lozenge. The pH drop for Suscard was not significant when normal oral hygiene procedures preceded the test.(ABSTRACT TRUNCATED AT 250 WORDS)