In a previous study, citric acid‐conditioning of the root surface greatly improved the rate of success of new‐attachment procedures in periodontal furcation pockets in mandibular premolars of Labrador retrievers (Crigger et al. 1978). In the present study, this experimental approach was tested in six beagles. The furcations on one side in each dog were reoperated six weeks after the first surgery. In 27 of the 35 treated teeth, mesiodistal sections showed closure of the furcation and new connective tissue attachment including deposition of new cementum. The extension of new attachment in the buccolingual dimension of the furcation, however, was not improved by repeating the surgical procedure.

The purpose of this study was to evaluate the caries-inhibitory effect of TiF4 as compared with equimolar solutions of neutral and acidified NaF. Sixty Sprague-Dawley rats were weaned 19 days after birth and given a cariogenic diet. They were randomly divided into four groups and given a 1-min topical treatment of the molar teeth on day 1 and day 17 of the experiment with the following solutions: group 1: 1% TiF4, pH 1.5; group 2: 1.3% NaF, pH 7.0; group 3: 1.3% NaF, pH 1.5; and group 4: control, distilled water. From day 2 the rats were inoculated with Streptococcus mutans twice weekly. On day 55 the rats were killed, and caries scored in accordance with Keyes. Total caries scored were (mean +/- SD): group 1, 12.7 +/- 9.5; group 2, 17.4 +/- 8.6; group 3, 14.3 +/- 9.7; and group 4, 29.5 +/- 9.0. There were significantly (p less than 0.05) reduced caries scores for total caries and for buccal + lingual and sulcal areas for all test groups as compared with the control group. Differences between control and test groups in proximal surfaces and between fluoride groups were non-significant. The results showed that the caries-inhibitory effect of TiF4 is at least as good as that of NaF in rats.