摘要:

The dental ages of 149 children born and grown up in a district with naturally occurring fluoride in the drinking water (maximum level 2.0 mg/1) were compared with those of 181 control children born and grown up in a neighbouring low-fluoride district (≤0.1 mg/1). The children were 9–12 years old. In neither group did the dental ages prove to differ from normality. It is concluded that concentrations below the highest recommended level fluoride occurring naturally in the drinking water do not seem to have any long-term effect on the individual physiologic maturation, as judged from the dental age of the growing child.

ISSN:0001-6357    

DOI:10.3109/00016357509004620

出版商:Taylor&Francis    

年代:1975

数据来源: Taylor

摘要:

A study of the projection of root canals of natural teeth on dental roentgenograms was carried out as a sequel to an earlier phantom study. The material consisted of extracted teeth and teethin situin jaw preparations. The same radiation source and focus-film distance were used throughout, but the exposure times and tube voltages were varied. The roentgenographic images of the root canals were analysed densitometrically and compared with measurements of the actual object dimensions. The root were sectioned at the level studied and their cross sections were traced and measured with the aid of a profile projector.There was good agreement between the true breadth of the canal and that projected on the film. The maximum contrast in the image of the canal and the densitometrically measured difference in substance, expressed in metal equivalents, were proportional to the depth of the canal in the direction of radiation. The breadth of the canal in the plane of the film was the same regardless of whether the tube voltage was 50, 60 or 90 kV. On the other hand, the tube voltage affected the photographic density differences between the canal and the dentine walls. Changing the voltage from 50 to 60 kV did not affect the results, but there was a highly significant difference between 90 and 50 or 60 kV. The clinical significance of tube voltage and exposure time is discussed.

ISSN:0001-6357    

DOI:10.3109/00016357509004621

出版商:Taylor&Francis    

年代:1975

数据来源: Taylor

摘要:

The influence of different stone mixing agents, impression materials and lubrication methods on the surface hardness of a stone die material has been evaluated. For one impression material the dimensional effect of the mixing agents and lubrication on the dies was also studied. The stone die material was mixed with water or a gypsum hardener and allowed to set on surfaces of glass, agar-agar, polyether, polysulfide and silicone impression materials. The lubrication methods for the stone were mineral oil, water soluble lubricant and mineral oil followed by water soluble lubricant. The surface hardness was measured according to the Brinell test. The Brinell test was chosen after a comparative study of the Brinell, Vickers and Knoop hardness test methods. The results showed that gypsum hardener was preferable to distilled water. The impression materials appear to have influence on the surface hardness of stone. The effect differed on water mixed and hardener mixed stone which emphasizes the importance of the mixing agent. All lubrication decreased the surface hardness of stone. With hardener mixed stone the combination of mineral oil followed by water soluble lubricant seemed preferable. Neither the gypsum hardener nor the lubrication influenced the dimension of the stone die material.

ISSN:0001-6357    

DOI:10.3109/00016357509004622

出版商:Taylor&Francis    

年代:1975

数据来源: Taylor

摘要:

The effects on plaque induced by the use of xylitol-and sucrose-containing chewing-gums were studied on ten test-persons with neglected oral hygiene during two three-day periods. The chewing of three, as well as of ten pieces per day of a xylitol chewing-gum resulted in a significant reduction in the amount of plaque and in the decrease of activity of invertase-like enzymes in plaque extracellular phase, when compared to corresponding conditions where a sucrose-containing chewing-gum was used.

ISSN:0001-6357    

DOI:10.3109/00016357509004623

出版商:Taylor&Francis    

年代:1975

数据来源: Taylor

摘要:

The effects on plaque induced by single or repeated use of xylitol-and sucrose-containing chewing-gums were studied on twenty subjects refraining from tooth-brushing for three days. Mechanical removal of plaque by chewing during a single period was shown to yield no significant differences between gravimetric values obtained before and after chewing. Daily use of a xylitol-containing chewing-gum reduced by 47% the weight of plaque formed in comparison to a sucrose-containing product, and by 20–41% in comparison to conditions when no chewing-gum was used. The use of a xylitol chewing-gum induced a lower invertase-like activity in plaque extra cellular phase. Results at variance with the gravimetric data were obtained by using a stained plaque scoring system; the eventual inadequacy of such plaque scoring systems was discussed.

ISSN:0001-6357    

DOI:10.3109/00016357509004624

出版商:Taylor&Francis    

年代:1975

数据来源: Taylor

摘要:

In 100 patients with denture stomatitis cultures and direct smears were used to evaluate 5 treatments, including sucking of chlorhexidine, amphotericin B or placebo tablets combined with denture soaking in 0.2 % chlorhexidine or water. After 14 days of treatment the amphotericin B lozenges had brought about a significant reduction in the quantity of fungus on the oral mucosa, whereas they barely affected the large amount present on the fitting surface of the upper denture. Denture immersion in chlorhexidine significantly reduced the number of organisms both on the mucous membrane and on the denture. It therefore seems at least as important to treat the denture as the patient in denture stomatitis. Fourteen days after withdrawal of the drugs the mycotic flora was largely re-established.

ISSN:0001-6357    

DOI:10.3109/00016357509004625

出版商:Taylor&Francis    

年代:1975

数据来源: Taylor

摘要:

The clinical effects of an antibacterial substance with antifungal activity (chlorhexidine) and a specific antimycotic (amphotericin B) in denture stomatitis were studied in 100 patients. Five 14-day regimens of chlorhexidine, amphotericin B or placebo lozenges combined with denture immersion in 0.2% chlorhexidine or water were tested. The efficiency of amphotericin B and chlorhexidine was comparable. This indicates that chlorhexidine has a considerable antifungal effect in the oral cavity and, further, that fungi are the responsible micro-organisms in denture stomatitis rather than bacteria. Chlorhexidine frequently discoloured the dentures. A high incidence of local and general predisposing factors to denture stomatitis, as well as of relapse 14 days after treatment, was observed.

ISSN:0001-6357    

DOI:10.3109/00016357509004626

出版商:Taylor&Francis    

年代:1975

数据来源: Taylor

摘要:

The intention of this work was to describe the nose morphology in individuals with different craniofacial patterns which dentally were characterized by Angle Class I, Class II div. 1, and Class III occlusions. The material comprised male adults (age 20–30 years), and the results are based on measurements on tracings of lateral cephalograms. Generally, the inclination of the nose in relation to the nasion-sella-line was similar in all groups, and so was the nose length as well. The depth of the nose, when related to the hard and soft tissue facial planes was, however, significantly different, apparently due to the different sagittal position of the chin.

ISSN:0001-6357    

DOI:10.3109/00016357509004627

出版商:Taylor&Francis    

年代:1975

数据来源: Taylor