Cleaning effect of toothbrushing with three different toothpastes and water.

The cleaning effect of three different toothpastes and water was studied in vivo using a laser reflexion technique. Ten healthy persons formed the test group. Light reflexion measurements on the upper front teeth were performed before and after the removal of a 72-hour plaque-pellicle. The results suggest that the toothpaste containing sodium bicarbonate as abrasive was less effective than a toothpaste containing aluminium silicate, calcium carbonate and dicalcium-phosphate dihydrate or silicon dioxide and dicalcium phosphate dihydrate. The abrasivity of the toothpastes was compared in vitro. The in vitro results correspond quite well to the in vivo findings.

The influence of silicone oil in toothpastes on abrasion in vitro.

The influence of addition of silicone oil to toothpastes was investigated in vitro using a laser reflexion technique and a profilometer. Acrylic plates were subjected to brushing in a brushing machine containing a toothpaste-water slurry. Four different toothpastes were used with and without the addition of 10% silicone oil. The results showed that the addition of silicone oil to a toothpaste decreased the abrasion rate and made the surface of the treated material smoother than after brushing with the original toothpaste.

Surface changes on dental materials. II. The influence of two different dentifrices on surface roughness measured by laser reflexion and profilometer techniques.

Surface changes on eight different dental materials were investigated, using laser reflexion technique and a profilometer. The tested materials were: Acrylic veneers Isosit, Isosit N, K+B+, Multiplus and K+Bpaste Gold Sjödings C Titanium pure non-rolled titanium Ceram a potential ceramic direct filling material The materials were subjected to brushing in a brushing machine, with a toothpaste-water slurry. Two different toothpastes were used separately; Clinomyn and Colgate. The new ceramic material showed no measurable wear by the brushing. All the other materials were affected to some extent. On titanium increasing values of light intensity were obtained thus indicating a smoother surface. Among the veneer materials K+Bpaste was the most wear resistant.

Surface changes on dental materials. The influence of two different dentifrices on surface roughness measured by laser reflexion and profilometer techniques.

Surface changes and wear resistance were investigated on eight different dental materials, using a laser reflexion technique and a profilometer. The tested materials were: (table; see text) The materials were subjected to brushing in a brushing machine, containing a toothpaste-water slurry. Two different toothpastes were used separately; Clinomyn and Colgate. The results showed that all the materials were to some extent affected by the brushing. Titanium was the most and SR Isosit N the least wear resistant material. Clinomyn and Colgate influenced the materials in different ways depending on their abrasive properties.

Dentifrice abrasivity. The use of laser light for determination of the abrasive properties of different silicas. An in vitro study.

The abrasive properties of five different silicon dioxides were investigated using laser reflexion. The substances were milled, amorphous silica gels of which four were commercially available dentifrice ingredients (Syloblanc) and one an experimental product. The abrasion process was carried out on acrylic plates in a brushing machine using two series of slurries of the substances, with and without sodium lauryl sulphate. Significant differences in abrasivity of the substances were observed. When sodium lauryl sulphate was included, the rate of abrasion decreased for the Syloblanc substances but increased for the experimental substance. The contrast was primarily explained by the capability of the different substances to form stable foams owing to their thickening properties. The investigation confirmed that silicon dioxides exhibit a wide range of abrasivity and proved that sodium lauryl sulphate influenced the abrasion process.

Lustre changes on teeth. The use of laser light for reflexion measurements on the tooth surface--in vivo.

Lustre changes on teeth in vivo were studied with the use of equipment based on a helium-neon gas laser. Variations of the intensity of laser light reflected from the tooth surface were measured under different conditions of accumulation and removal of deposits, which were assumed to consist mainly of the pellicle. The possibility of using fluoride varnish as an artificial surface layer in this kind of investigation was also tested but rejected. Measurements were made after toothbrushing with water alone and with two toothpastes possessing different degrees of abrasivity. Teeth that had been left without toothbrushing for 24 hours showed statistically significant (p less than 0.05) lower light reflexion values than those recorded immediately after the teeth had been brushed with a toothpaste. During a period of seven months, persons brushing their teeth with water alone generated lower intensity values than did those brushing with the two toothpastes. The more abrasive paste yielded the highest intensity values, indicating a more polished or cleaner surface. The results suggest that the use of a toothpaste containing abrasives contributes to the cleaning effect of toothbrushing.

Dentifrice abrasivity. The use of laser light and supplemental techniques for characterizing toothpastes containing different abrasives. An in vitro study.

The abrasivity characteristics of six commercially available toothpastes containing different abrasives were investigated by using laser light reflexion and radiotracer methods. Surface profile and laser diffusometer measurements were also included in the study. Significant and, in some cases, substantial variations of abrasivity were observed. A certain correlation between the results of the different methods was found and used for purposes of ranking the toothpastes. The investigation indicated a necessity to use a combination of quantitative and surface descriptive methods in order that a complete picture of the abrasive properties of a dentifrice might be obtained. The importance of including other than biological materials in the test was also emphasized.

Lustre changes on teeth. The use of laser beams for comparative studies in vivo.

An instrument for studies of lustre changes on teeth in vivo was constructed and evaluated. The equipment was based on a helium-neon gas laser, a coordinate screen and a photocell. The intensity of light reflected from incisors of ten test subjects was measured before and after brushing with different dentifrices. The investigation showed that the instrument was useful for measuring intensity differences of laser light reflected from teeth. The intensity was found to vary within wide limits from teeth of different persons. During a test period of 70 days only few lustre changes caused by dentifrices were registered.