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Mixed saliva stimulated by mastication was sampled under standardized conditions in 50 recruits before and after a 10-day period of intensified oral hygiene. The degree of gingivitis was assessed (1) with the Sulcus Bleeding Index and (2) with the spectrophotometric determination of blood iron in the saliva samples. Oral hygiene reduced (1) the SBI from 1.1+/-0.6 to 0.6+/-0.4 and (2) salivary iron from 0.6+/-0.5 to 0.3+/-0.4 mug, both differences being highly significant (PF is less than 0.001). SBI and iron data were significantly but not strongly correlated (r=51).

Experiences of 7 years with sugarless chewing gums and lozenges (tab. I and II) regarding their tooth protective properties are reported. Telemetry of interproximal plaque pH allows to assess acid formation from carbohydrates by plaque bacteria under almost natural conditions. Altogether, 5 chewing gums and 8 lozenges containing sorbitol or mixtures of sorbitol and hydrogenated oligosaccharides were investigated. Lowest pH values during and after chewing sugarless gums varied between pH 6.0 and 7.3. When sucking sugarless lozenges the recorded pH values were between 5.8 and 7.0. In contrast to lozenges, the consumption of sugarless chewing gums becomes particularly important due to their greater stimulation of saliva and buffering capacity of oral fluid. All products tested did not acidify interproximal plaque below the critical pH and therefore comply with the regulations of the Swiss Federal Health Authorities with respect to the labeling or marketed sweets with "safe for teeth". New non-fermentable sugar-replacing substrates are being developed. Their utilization in foodstuffs and sweets is being discussed.

The advantage of pH-telemetry of plaque and mixed saliva in the evaluation of the cariogenic potential is that, in contrast to in vitro measurements, in vivo telemetry discriminates among pH variations in plaque and saliva as a result of substrate fermentation and those due to dietary acids, acids formed by the oral mucosal microflora and adequately registers salivary buffers. This is illustrated with a summary of acido- hypo- and nonacidogenic products tested.

Although collective and individual prophylactic measures have been shown to drastically reduce or totally prevent dental caries and periodontal disease, a recent survey of over a thousand twenty-year olds from all areas in Switzerland revealed an average DMFT value of 14.5, including 8.6 teeth already filled. Alarmingly, more than two thirds of all the proximal fillings examined radiographically were inadequate and therefore sources of marginal irritation. Dentistry in the future must accordingly concentrate on increased primary prevention and, where restorations are necessary, on placing restorations that will not lead to secondary caries and destructive marginal periodontitis. These goals can be most economically achieved through a team approach where the dentist delegates to his (or her) dental hygienist and specially trained chairside assistant the tasks of radiological and clinical diagnosis of caries and of marginal irritants in order to interfere with the progress of periodontal disease. The dentist, in addition, freed from administrative tasks by electronic data processing, will direct the team, and his practice will, in the future, fall into one of two large areas: preventive dentistry and/or pedodontics of curative gnathology.

Three experiments performed on Osborne-Mendel rats tested the effects on erosion of the topical application of aluminum, cerium and titanium salts as well as sodium fluoride and sodium mono-fluorophosphate. In two experiments the compounds were applied during the erosion period and in a third trial, the test substances were applied prior to exposure to the erosive agent which was fermented apple juice. While cerium had no significant effects on erosion, aluminum fhloride and titanium chloride significantly increased the severity of erosive tooth destruction. Only sodium fluoride and sodium mono-fluorophosphate were effective in preventing erosion.

Class II Adhesive Restorations have been realized with composites under laboratory conditions. They show a perfect marginal adaptation and no microleakage at the tooth/restoration interface. These properties were obtained a) with a new cavity preparation, b) by application of a low viscosity sealant prior to the placement of the bulk of the composite material. The Adhesive Restoration compared favorably with conventionally prepared restorations. Nevertheless, enamel conditioning with acid and the use of a low viscosity sealant in conventionally prepared class II cavities resulted also in some improvement of marginal adaptation.

L-sorbose, xylitol and sorbitol solutions (56 mM) were not hemolytic when incubated with erythrocytes of 30 healthy volunteers, 14 thalassemic heterozygotes and in 30 horses, 30 cows and 30 Osborne-Mendel rats. Lysis of dog erythrocytes was most pronounced when incubated with L-sorbose but was also significant in xylitol and sorbitol solutions.

A new telemetric system was used to determine, simultaneously, plaque pH and salivary fluoride when sucrose-containing fluoride tablets of 0.25 mg and 1.0 mg NaF were dissolved in the oral cavity. Dissolution of 1.0 mg fluoride tablets on the dorsum of the tongue produced transient interproximal plaque acidification not lower than pH 5.2 combined with an increased salivary F-level between 0.19 and 19 ppm for up to 1 hr at the entrance of the interproximal space. Interference of plaque glycolysis by F was evident when rinsings with 250 ppm F as NaF combined with 10% sucrose resulted in pH levels 1/2-1 unit higher than with 10 percent sucrose alone. The use of sucrose as a vehicle in fluoride tablets is discussed.

The ability of two different toothbrush bristle ends to produce traumatic gingival abrasion was assessed in a double blind study on 15 male and 15 female young adults. Brushing was performed in a circular fashion using a modified Bass technique. An apparatus allowing continuous visual feedback of the average brushing force permitted a degree of standardisation of the system. The upper left canine and bicuspid area had to be brushed for 30 seconds with cut toothbrush bristles (CP) and with round ended toothbrush bristles (RP) respectively. A two-week interval separated the two brushing sessions. Traumatic lesions of the attached gingiva were stained with a disclosing solution, photographed and evaluated planimetrically. The "cut bristles" caused gingival abrasions 30% greater in extent than the round end bristles. The difference was not due to single brushing strokes accidentally greater for the "cut bristles". The size of the lesions was not sex-dependent.

The clinical aspects, epidemiology, etiology and pathogenesis of dental erosions in man and experimental animals are reviewed. Abrasion of enamel, softened in orange juice for 3 minutes and brushed with various dentifrices, was studied with Knoop hardness measurements and scanning electron microscopy. Knoop indentations made on softened enamel surfaces were almost totally removed by 2-minute brushings with highly abrasive tooth pastes. Brushing without dentifrices only slightly changed the distinctness of the indentation outlines. Recommendations for primary and secondary prevention of erosions are given.

180 fluoride biopsies were taken in 30 children from the labial surfaces of the 6 maxillary anterior teeth. The average thickness of the biopsied surface enamel was 8.35+/-0.75 mjm. Intact, not treated enamel had an average F-content of the integral of 550 ppm. 7 days after one 3-min topical application of amine fluoride on intact enamel the average F-concentration was the integral of 1150 ppm. 7 days after one amine fluoride application on enamel previously etched with pyruvic or orthophosphoric acid, the average F-content was the integral of 3400 ppm and the integral of 2800 ppm respectively.

Labial enamel surfaces of anterior teeth were polished, etched for thirty seconds with acid and then repolished by manual brushing with three different abrasive pastes for 10, 15, 15, 20, and 20 seconds respectively and finally for a 60-sec brushing with a dental engine. Before etching and following each paste treatment, the light reflection of the surfaces was measured with the scanning tooth surface reflectometer of GABATHULER. The reflectance values were compared with the microscopic tooth surface texture. Reflectometric findings were similar under in vitro and in vivo conditions. There were differences among the pastes in restoring maximum lustre of dull etched enamel, but not in polishing intact tooth surfaces.

Stimulated mixed saliva and interproximal plaque were exposed to the ketohexose sorbose. The average pH of an in vitro 1%-sorbose/saliva mixture increased with time when compared with a highly significant pH-decrease of a sucrose/saliva mixture. In contrast to sucrose rinses, the telemetrically recorded pH of interproximal plaque did not drop below pH 5.5 during and subsequent to rinsing with sorbose solutions.

The marginal integrity of MOD adhesive restorations of a thixotropic test composite (ZKP-A-5) and of two injection-capsule composites (Concise -capsule composite and Compocap-S) was examined. Dy penetration tests measured microleakage and scanning electron microscope evaluated marginal adaptation. The test restorations showed no improved micromorphological marginal adaptation when compared to those of a standard paste-paste composite (Concise). Compocap-S demonstrated better prevention of microleakage than did the other test preparations. The marginal quality of these thixotropic and injection-capsule composite restorations was improved from 34% to 52% with utilization of a sealer application (ZKP-A-2), (Concise-Enamel Bond). The application of a sealer prior to insertion of thixotropic and injection-capsule composites is, therefore, definitely indicated when these materials are used. The resultant restorations obtained with these test materials plus sealer correspond qualitatively to those of standard composites Concise or Adaptic [6,7]. The newly developed, complete composite systems (Nimetic, GC's Epolite 100/Epobond) demonstrated in comparison to Concise and Adaptic [6,7] inferior results.