摘要:

Abstract—A definition of bristle stiffness and a measuring method are described and discussed. Sixty‐six different brush models, collected worldwide, were measured according to the suggested method. Considerable differences were found between brushes of declared equal stiffness. On the basis of these findings and the method described, a classification is sugges

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1979.tb00668.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract—During growth the rat skull straightens considerably due to flexions between skull parts and individual bones. This straightening is defined as orthocephalization. Orthocephalization might also be caused by a change in head posture during growth, i.e. it may be “apparent”. In order to study the significance of this phenomenon, radiographs of dried skulls of male rats, 14, 30 and 60 d of age were subjected to angular measurements between the plane of the lateral semicircular canal and the plane of foramen magnum and of the basisphenoid bone, respectively. When the plane of the lateral semicircular canal is placed horizontally, the head is claimed to be in natural position. No changes in the angulation between the lateral semicircular canal and the basisphenoid bone could be revealed, whereas the foramen magnum was shown to rotate upwards and backwards in relation to the plane of the canal. This implies that the orthocephalization which takes place between 14 and 60 d is caused only by real angular changes, and that no apparent changes occur due to changes in head po

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1979.tb00669.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract—The purpose of the present study was to compare efficiency of measurements commonly used to study the development of plaque and gingivitis in short‐term clinical trials. Data from a recent experiment on the effect of mutanase on accumulation of plaque and development of gingivitis were used. Efficiency was compared using 1) level of significance and 2) minimum number of individuals necessary to obtain a statistically significant result at a given level of significance and with a given power of the test. Of all the measurements used, the gingival exudate measurement was the most efficient. Among the nonparametric indices, Plaque Index was the most efficient, especially on proximal surfaces in the mandible. Reduction of the scales for the nonparametric indices from a four‐point scale to a two‐point (dichotomous) scale slightly reduced experimental eff

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1979.tb00670.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract—Using immunofluorescent techniques and anti‐actin antibodies the presence of actin filaments has been demonstrated in epithelial cells cultivatedin vitro. Organized bundles of filaments are restricted to the marginal cells in epithelial sheets. These marginal cells are not contact‐inhibited and show structures like membrane ruffies which are common for migrating cells. In contrast, internal cells in the epithelial sheets are diffusely stained by anti‐actin antibodies. The actin in all cells is redistributed after incubation in media containing cytochalasin B (CB). The importance of organized actin‐filaments in migrating epithelial cells is

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1979.tb00671.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract—The concentrations of Ca, Mg, Mn, Sr and Zn in supra‐ and subgingival calculus collected from mandibular anterior teeth mainly of the same persons were analyzed with atomic absorption spectmphotometry. The results showed highly significantly (P<0.001) greater Zn and Sr concentrations in subgingival samples. The mean value of Zn was 5.4 times higher in subgingival calculus than in supragingival calculus. In contrast, the concentration of Mn was significantly (P<0. 01) higher in supragingival calculus. The difference in the concentration of Mg in supra‐ and subgingival calculus was highly significant (P<0. 001) only when samples from the same person were compared. The concentration of Ca was very similar in both types of calculus and individual variations were very

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1979.tb00672.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract—Mentally handicapped children, aged 5–15 years and living in institutions, received fluoride supplement in several sugar products of their diet; in candies, marmalades, jams, fruit juices and in sweet desserts corresponding to 10 mg F as NaF per kg of the sugar (sucrose or glucose) of each product. To two of the four daily candies was also added a NaHCO3+KH2PO4mixture (mole ratio 9.8/1, resp.) to substitute for 2.5% of the sugar of the candy. The control children received the respective products without the additives. After stepwise exclusions of subjects for various reasons, e.g. for the absence of permanent teeth, low initial caries activity, strong medication, Down's syndrome, etc, the mean DMFS‐increment in the remaining 48 control subjects was 4.5 and in the 41 test subjects 2.6 lesions/100 surfaces at risk, i.e. 42% reduction. Caries arrestment had occurred in these test subjects after the first year, while in the respective controls it was cantinuously increasing. Among numerous oral and body parameters. studied, only surface enamel fluoride in primary teeth was increased by the fluoride supplements and urinary phosphate and calcium excretion decr

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1979.tb00673.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract—The aim of this study was to evaluate whether formocresol can be used successfully in teeth with carious exposure and a vital pulp with clinical symptoms of chronic pulpitis. Further, the study concerned the influence on the success rate of the vehicle for formocresol. Pulpotomies were performed on 81 primary molars. Radiographic and other clinical symptoms were used to divide the material into a coronal chronic and a total chronic pulpitis group. Chosen by lot, zinc oxide‐eugenol or Pharmatec® (a plaster‐like non‐eugenol cement) was used as the vehicle for formocresol. After an observation period of 2.5 years the success rate for the whole material was 55%. No statistically significant difference in the rate of success could be demonstrated either between the two diagnostic groups or between the two vehicl

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1979.tb00674.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract—Effects of endodontic retreatment on quality of seal and periapical healing were assessed among 660 previously root‐filled roots. The roots were divided into either of two groups according to presence or absence of pathologic alterations in the periapical area. The retreatments, which were carried out by dental students, involved a thorough chemomechanical debridement of the root‐canal system aiming to control infection. Following a 2‐year observation period 556 roots were reexamined clinically and radiographically. The results showed that root‐fillings with technical shortcomings could, following retreatment, be markedly improved as regards effectiveness of seal and distance to the apex. A large number of lumina discernible apical to root‐filling could also be treated and filled. Seventy‐eight percent of the cases with pathologic lesion present periapically prior to retreatment either completely healed or displayed an obvious size‐reduction of the process Retreatments carried out because of technical inadequacies alone were successful in 94% of the cases. It was concluded that renewed endodontic treatment whenever possible is the method of choice when treating defective endodontic fillings complicated with pathologic processes periapically. Apical surgery may be attempted if no signs of healing are apparent follow

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1979.tb00675.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract—A study was carried out to develop a histomorphometric method for indication of individual level of cortical width (MCW) and absolute cortical bone mass (MCW×% bone mass in mm3/mm2bone surface) in the mandibular body and to demonstrate possible differences as to site, side, state of dentition, sex and age. The material consisted of autopsy specimens of mandibles. Microradiograms of 100‐μm‐thick buccolingual ground sections were used. An electronic point‐counting system (Leitz‐Classimat®) was used for determination of MCW. The values for percentage of cortical bone mass have been given in previous studies. The analysis indicates that: 1) a reproducible measure for MCW in μm and absolute bone mass in a standard site can be obtained; 2) MCW in other sites of mandibular cortex deviates from that of standard site, which is why the same site has to be used in interindividual analysis; 3) MCW and absolute bone mass in the standard site are independent of side, state of dentition and sex, but show age‐related decreases, while 4) the lingual cortex is unsuitable for interindividual

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1979.tb00676.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

Abstract—A system has been developed for examining connective tissue influence on keratinization of normal and leukoplakic human oral epithelia. Paired biopsy specimens of normal and leukoplakic mucosa were left intact or were incubated in 1 mM EDTA to permit epithelial‐connective tissue separation and various recombinations of the epithelium and connective tissue. The tissues were transplanted to subdermal sites of “nude” (nu/nu) mice and were protected by polyethylene capsules. 44% of implants performed were recovered apparently vital. Preexisting structure was retained after epithelial‐connective tissue separation and self‐recombination. Cross‐recombined specimens showed changes in patterns of keratinization including changes of keratinized leukoplakic epithelium to a nonker

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1979.tb00677.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY