摘要:

The present study reports on the prevalence of hypodontia in a Norwegian population and classifies children with hypodontia according to need of orthodontic treatment. Orthopantomograms of 1953 children (960 girls and 993 boys) at the age of 9 were available for examination. Of the boys registered with hypodontia of second premolars at the age of 9, 11.3% showed late mineralization between the ages of 9 and 12. Only 2.9% of the girls showed late mineralization. The corrected prevalence of hypodontia, excluding third molars, in the girls was 7.2%, in the boys 5.8%, and in both sexes combined 6.5%, the difference between sexes not being statistically significant. Of the children with hypodontia, 86.6% lacked only one or two permanent teeth. The most frequently missing teeth were the mandibular second premolars, the maxillary second premolars, and the maxillary lateral incisors, in that order. Classification of children with hypodontia according to need of orthodontic treatment showed that about two‐thirds had hypodontia only of single posterior teeth with a moderate need of treatment. About one‐third had hypodontia involving anterior teeth, and only 3.1% had hypodontia of two or more teeth in the same quadrant with a great need of treatm

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1993.tb01115.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The rate of dentin mineralization and the influence of indomethacin on the dentin mineralization rate during orthodontic treatment was determined in miniature pigs by intravital labeling with tetracycline. The results demonstrated that the dentin mineralization rate in the control animals was 3.8 μm/day, a rate corresponding to that of human teeth. Both indomethacin and orthodontics had an effect on the dentin mineralization rate, indomethacin reducing and orthodontic forces increasing it. In combination, the two factors neutralized each other

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1993.tb01116.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

An atypical, rapidly proceeding abrasion/erosion of the labial enamel surfaces of the maxillary and mandibular incisors and canines in a 27‐yr‐old man is reported. Ultrastructural examination of a replica of the teeth showed a practically structureless enamel surface both at the initial examination and after 12 months. However, at the end of the period, minor areas of dentin tubules became visible, indicating that a substantial loss of the tooth substance had taken place. The patient's occupation involved daily environmental contact with proteolytic enzymes. In vitro study of enamel exposed to one of the actual proteolytic enzymes showed dissolution of enamel substance, and it cannot be excluded that enzymatic decomposition of the organic enamel matrix is a contributing cause of the observed exaggerated loss of tooth substa

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1993.tb01117.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The tunnel preparation method is designed to remove approximal caries through a channel from the occlusal surface while preserving the marginal ridge. This method entails reduced access to the caries lesion and thereby uncertainty as to the complete removal of caries. The purpose of the present investigation was to study the effectiveness of caries removal in 60 extracted premolars and molars by the partial tunnel preparation method. The glass polyalkenoat (ionomer) filling and the distance to the pulp were also examined. Examination of the sectioned teeth showed residual caries in the axial wall of two teeth and in dentin close to the enamel lesion in 10 teeth. Very few porosities were found within the glass polyalkenoat material and at the interface between the filling and the cavity walls.

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1993.tb01118.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The aim of the present investigation was to compare the clearance pattern in saliva and the salivary stimulating effect of a new fluoride (F) chewing gum (Fluorette) with three other F products used in Scandinavia for many years for caries prevention. Concentration of F was determined in whole saliva in three groups of subjects: 1) children, 10–12 yr of age (n= 20), 2) adults (n= 20), and 3) dry mouth patients (n= 15), after a single intake of the two tablets, Dentan and Fludent, and the two chewing gums, Fluomin and Fluorette, all containing 0.25 mg F as NaF. Sucking was allowed until the tablets had been completely dissolved in the mouth. The chewing gums were used for 15 min. Saliva samples were collected from subjects expectorating 0.3–0.5 ml at nine different time intervals up to 45 min after the intake. There were some significant differences in the maximum F concentration, the area under the salivary fluoride concentration curve (AUC) when plotted against time, and the salivary stimulating effect among the four products, but as a whole they were small and probably of minor clinical importance. Among the various groups, the dry mouth patients showed the highest salivary F concentration. Thus, the main conclusion from this study is that the F tablets and chewing gums studied, including the new product Fluorette, had approximately the same clearance pattern in saliva and the same salivary stimulating effect. However, there were great variations among the different subje

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1993.tb01119.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

High concentrations of tissue plasminogen activator (t‐PA) and placental type plasminogen activator inhibitor (PAI‐2) have previously been found in gingival crevicular fluid (GCF) of adults. In the present study, the levels were examined in 16 children aged 8–9 yr. Sampling of GCF was performed with small disks of Millipore‐filter. t‐PA and PAI‐2 were analyzed with enzyme‐linked immunosorbent assays with low method errors. The mean concentration of t‐PA was slightly higher than in adults, while the mean PAI‐2‐concentration was slightly lower. An intraindividual study comparing healthy and inflamed sites in the children showed slightly higher concentrations in GCF from inflamed sites. No change was observed in the balance bet

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1993.tb01120.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

Gingival overgrowth was assessed in renal transplant children, 19 boys and 13 girls, aged 2.5–18 yr, who had been on a cyclosporin‐A (CsA)‐based immunosuppressive regimen for at least 12 months. Data collected included number of posttransplant months, total CsA dose administered during the first 6 posttransplant months, oral dose and blood trough level of CsA on the day of examination, plaque accumulation (VPI%), gingival inflammation (GBI%), loss of attachment, and gingival overgrowth. Thirteen percent of the children exhibited gingival overgrowth characterized by one or more units with increased sulcus probing depth (≥4 mm), i.e. pseudopockets. The total amount of CsA administered during the first 6 posttransplant months was significantly higher in the children with gingival overgrowth than in those without. The study indicates that the development of CsA‐induced gingival overgrowth is positively related to the total dose of the drug administered to the children during the first 6 posttranspla

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1993.tb01121.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The effect of systemic doxycycline administration on frequency of root resorption cavities and extent of bone loss following periodontal surgery was studied in albino rats. Thirty Wistar rats with healthy gingiva were divided into four groups. Six untreated animals (Group 1) served as controls. Gingivectomy (Group 2, six rats), mucoperiosteal flap operation (Group 3, eight rats), and mucoperiosteal flap operation with doxycycline added to the drinking water (Group 4, 10 rats) were performed on the palatal aspect of maxillary left molars. After a healing period of 3 wk, the rats were killed by an overdose of sodium pentothal, and specimens of first molars were prepared for light microscopy. Root resorption was absent in normal and gingivectomized animals (Groups 1 and 2). Resorption cavities occurred in all flap‐operated animals (Group 3) and in one of 10 doxycycline‐treated animals (Group 4). The distance from cementoenamel junction to alveolar bone crest remained unchanged in gingivectomized (Group 2) and doxycycline‐treated animals (Group 4), as compared with control specimens. In flap‐operated animals (Group 3), the crestal bone level was located more apically than in doxycycline‐treated rats (Group 4). This study has shown that root resorption and bone loss were associated with flap operations involving exposure of periodontal ligament and bone. Systemic doxycycline prevented both root resorption and

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1993.tb01122.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

The present investigation was designed to study the number of mast cells in various oral mucosal sites in juvenile and adult rats, with special reference to presence of subtypes of mast cells. Fifteen juvenile (1‐month‐old) and 15 adult (6‐month‐old) rats were used. Biopsies were taken from tongue, bucca, marginal gingiva (incisor area), and intestine (jejunum). For optimal preservation of the stainability of subtypes of mast cells, a fixative with low aldehyde concentration and low pH was used. The biopsies were embedded in paraffinwax. The first of three consecutive sections (5 μ) was stained in toluidine blue for 30 s, the second in toluidine blue for 7 days, and the third in astra blue/safranine. The total number of mast cells was represented by all cells positive to toluidine blue after 7 days' staining, or the sum of cells positive to astra blue and safranine. Cells positive to toluidine blue after 30 s were classified as connective tissue mast cells (CTMCs), and those positive after 7 days, but not after 30 s, as mucosal mast cells (MMCs). Cells positive to safranine in the astra blue/safranine staining sequence were classified as CTMCs, and those positive to astra blue as MMCs. Cells with intermediate staining characteristics in the astra blue/safranine staining sequence were recorded separately. The total number of mast cells in the tongue, buccal mucosa, and gingival mucosa was significantly higher in the juvenile than in the adult rats. In the buccal and gingival mucosa, more than twice as many mast cells were found in the young animals. In the intestine, however, the juvenile rats showed a significantly lower number of mast cells. In general, a higher number of cells with histochemical characteristics similar to the MMCs of the intestine was found in the oral sites of the juvenile animals. The differences in the total number of mast cells and the different composition of the mast cell population in the two age groups may indicate an age‐related difference in the potential for biologic reactions involving

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1993.tb01123.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

In vitro susceptibility ofActinobacillus actinomycetemcomitans(A.a.) serotypes to selected antimicrobial agents was investigated by the agar dilution method on supplemented Mueller‐Hinton test medium. Eighty‐threeA.a. strains, 80 recent isolates from 40 periodontally healthy or diseased subjects, and three type strains were included in the study. Serotypearepresented 20, serotypeb32, serotypec17, and serotypee7 and nontypable 4 of the tested strains. The most effective drugs against allA.a. serotypes in vitro were cefaclor, cefuroxime, tetracycline hydrochloride, doxycycline, trimethoprim‐sulfamethoxazole (cotrimoxazole), and ciprofloxacin, which inhibited 100% of the strains at 4.0 μg/ ml, 4.0 μg/ml, 1.0 μg/ml, 2.0 μg/ml, 0.06 μg/ml, and 0.015 μg/ml, respectively. Serotypesaandewere more susceptible to cafaclor and cefuroxime than were serotypesbandc;100% of the first two groups were inhibited at 2.0 μg/ml and 1.0 μg/ml. Ampicillin inhibited 92% of the tested strains at 1.0 μg/ml. Serotypebwas always susceptible to ampicillin. Metronidazole exhibited the best activity against serotypeastrains. The lowest minimal inhibitory concentration values for benzylpenicillin, ampicillin, erythromycin, doxycycline, and metronidazole were encountered among serotypebisolates. The results of the present study indicate minor differences in the in vitro antimicrobial susceptibility patterns of differentA.a. serotypes, except to metronidazole. Also, the new oral cephalosporins and cotrimoxazole, rare antimicrobial agents in periodontology, showed promising efficacy against a

ISSN:0909-8836    

DOI:10.1111/j.1600-0722.1993.tb01124.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY