EFFECT OF BUCCAL ADMINISTRATION OF A LACTOSE-CONTAINING NITROGLYCERINTABLET (SUSCARD) ON PLAQUE PH

The aim of this study was to monitor pH in 2-day-old dental plaque aft er administration of a long-acting, lactose-containing nitroglycerin t ablet (Suscard). The tablet was placed under the lip of the maxilla. T his was done both in two older subjects suffering from heart problems and in 10 younger, healthy subjects. In the latter group, a sucrose-co ntaining 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 maxill a by the microtouch method. The Suscard tablet resulted in a fall in p laque pH in both groups when teeth had not been brushed for 2 days. Th e lowest pH was recorded at the sites close to where the tablet had be en placed. The most attenuated pH drop was found in the two older subj ects, who showed a mean minimum pH of 5.7, as compared with 6.2 for th e younger subjects. No further increase in the pH fall from Suscard wa s seen after the 5-wk period in the two patients with heart problems. In the 10 younger healthy subjects, the most pronounced pH decrease wa s registered after administration of the sucrose-containing lozenge. T he pH drop for Suscard was not significant when normal oral hygiene pr ocedures preceded the test. To conclude, this study showed that a long -acting, lactose-containing nitroglycerin tablet may be highly carioge nic. However, if good oral hygiene is maintained, the pH drop in plaqu e can be reduced to a minimum.