Effects of Glucose and Urea on Dental Deposit pH in Dogs

The pH of deposits that formed on the maxillary incisors, canines, and premolars of adult beagles 1, 3, and 20 weeks after prophylaxis was measured before and after the application of 5% glucose or 5% urea solutions. The pH decreased between 0.23 and 1.68 units after glucose, and increased between 0.69 and 1.96 units after urea. </jats:p

Spiramycin Excretion in Animals : III. A Single Oral Dose in Dogs

Spiramycin concentrations were determined in plasma and parotid and sublingual fluids of unanesthetized dogs 1 to 6 and 24 hours after a single oral dose of the antibiotic. Plasma levels were highest 1 to 4 hours after dosage. Sustained sublingual secretion and peak parotid levels of spiramycin occurred at later collection times. </jats:p

Effects of Fluorides in the In Vitro Plaque Model System from Human Salivary Sediment

Artificial plaque from human saliva produces glycolytic action after three to four hours incubation at 37 C. When 6 to 8 ppm F from aminefluorides is present, such effects are absent. Under the same conditions, up to 100 ppm F from sodium fluoride and monofluorophosphate are inactive; stannous fluoride is active at 50 ppm F, but not at 10 ppm F. A marketed preparation of a gel that contains aminefluoride is active at 80 ppm F, whereas an inorganic fluoride gel is active only at 1,250 ppm F. </jats:p

Spiramycin Excretion in Animals: II. Repeated Oral Doses in Rats

After 7 to 14 spiramycin doses, plasma and selected tissues were assayed for residual antibiotic. Plasma contained detectable spiramycin only in samples taken 24 hours after the last 400 mg/kg dose. After 100 to 400 mg/kg levels, spiramycin remained in mandibular gingiva and bone at least seven days. Parotid and submaxillary glands contained antibiotic 24 hours after 25 to 400 mg/kg doses and 14 to 21 days after 400 mg/kg doses. </jats:p

Effect of Inoculation on Bone Resorption Scores in Two Rat Strains

Inoculation with Actinomyces viscosus increased the alveolar bone resorption scores in one commercially available rat strain, but not in another. Bone resorption scores in inoculated rats differed with the strains tested. Advanced bone resorption occurred in 4 of the 24 sites measured, and 4 sites were resistant to bone resorption. The other 16 sites provided no additional information. The two mandibular mesial sites provided the most sensitive measure of bone resorption. </jats:p

Anticalculus and Antiplaque Activity of 8-Hydroxyquinoline Sulfate

8-Hydroxyquinoline sulfate inhibited formation of artificial calculus in vitro and rat calculus in vivo. In rats, it prevented calculus formation when applied by swabbing or by intraoral instillation. In dogs, formation of dental plaque was inhibited by 33 to 98% in comparison to placebo. Also in dogs, 25 to 58% of established plaque accumulations were removed by 8-hydroxyquinoline sulfate whereas placebo removed 2 to 22%. No systemic or local toxic effects were observed. </jats:p

Basic Biological Sciences

Solutions containing 0.2% of a bis-biguanide, chlorhexidine (positive control), and four bis-amidinourea antimicrobial agents were tested in beagle dogs in a 12-week study. The five agents significantly reduced clinical plaque and gingivitis scores, and gingival fluid volumes in treated dogs, compared with water. All compounds reduced the stain area scores compared to water controls. Stain intensity scores were higher for chlorhexidine than for the four new antimicrobial agents and the water controls. There were no overt behavioral changes. Histological examination of oral tissues revealed no irritation. </jats:p