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1.
Dental researchers have postulated that the risk factors for enamel and dentin caries may not be the same. A review of the literature ascertained that data to support this theory are lacking. OBJECTIVES: To evaluate the risk indicators of enamel and dentin caries of the permanent dentition in a study group who had limited access to fluorides and made limited use of dental services. METHODS: The study was conducted in Goa, India. Data came from a cross-sectional survey of 1189 seventh grade children, which consisted of a clinical dental examination and a self-administered questionnaire to their parents. The cavitated and non-cavitated criteria were used to score for caries, and the Silness-Loe index for plaque. RESULTS: The mean age of the children was 12.2 years. The percentage of children caries free in the permanent dentition was 22.2%, the mean+/-s for dmfs, enamel and dentin lesions were 4.20+/-5.10, 2.59+/-2.89 and 1.61+/-3.30 respectively, and the mean plaque score was 1.00+/-0.48. Results of regression analyses showed that the risk indicators of prevalence and severity of caries differed depending on lesion type. The only variable that was consistently a risk indicator of presence and severity of both dentin and enamel caries was poor oral hygiene. Mother's highest level of education and presence of fluorosis were also risk indicators of enamel and dentin caries. The presence of decayed primary teeth was a risk indicator of enamel caries; and fluorosis severity, use of fluoride toothpaste at the time of the survey, and toothbrushing frequency were risk indicators of dentin caries. The observed caries-oral hygiene association seen is explored further.  相似文献   

2.
During 1988-89, 224 patients with approximal caries in the premolar/molar regions were provided with 318 tunnel restorations. In case of perforation of the enamel in the enamel/dentin border, (23%), complete Class II-tunnel restorations with glass ionomer cement and composite resin were made. In case of "intact" enamel, (77%), partial Class I-tunnel restorations were made. The restorations were controlled at annual routine recalls and the success rate after 3 1/2 years was 74% for permanent teeth, and 10% for primary teeth. Restorations in permanent teeth, made during the second year of the study were successful in 82%, as compared with 62% for restorations made during the first year, indicating a learning effect. Failures in the permanent dentition were due to marginal ridge fracture (35%), cavitation in the approximal enamel (31%), and recurrent caries (38%). Failures in primary teeth were predominantly due to marginal ridge fractures (84%). A comparison with the longevity of conventional Class II restorations is made and the possible advantages of the present method are presented.  相似文献   

3.
This study describes mesial and distal enamel thickness of the permanent posterior mandibular dentition. The sample comprised 98 Caucasian adults (59 males, 39 females) 20 to 35 years old. Bitewing radiographs of the right permanent mandibular premolars and first and second molars were illuminated and transferred to a computer at a fixed magnification via a video camera. Enamel and dentin thicknesses were identified and digitized on the plane representing the maximum mesiodistal diameter of each tooth. The results showed that there were no significant sex differences in either mesial or distal enamel thickness. Enamel on the second molars was significantly thicker (0.3 to 0.4 mm) than enamel on the premolars. Distal enamel was significantly thicker than mesial enamel. There was approximately 10 mm of total enamel on the four teeth combined. Assuming 50% enamel reduction, the premolars and molars should provide 9.8 mm of additional space for realignment of mandibular teeth.  相似文献   

4.
The study was carried out on 80 teeth (70 of permanent dentition and 10 of primary one) of mandibular and maxillary bones. The teeth owned to subjects lived in the III c.b.C. in Sicily, and they were found in Naxos necropolis. The teeth were examined as far as carious and non carious lesions, then they were prepared for instrumental analyses by Scanning Electron Microscopy (SEM) and Energy dispersed X ray spectrometry (EDS). To an objective examination of the sample no caries were detected in the teeth sample apart one tooth, on the other hand there was an extensive occlusal abrasion, from a macroscopic point of view there were no difference as far teeth morphology. SEM examination pointed out all around dentinal tubules a circle of sclerotic dentin as reaction to occlusal wear. The amelocemental junction showed from a ultramicroscopic point of view an overlap of cementum onto enamel. EDS analysis pointed out a higher P concentration on the crown versus the root in all the teeth of the sample.  相似文献   

5.
Hallerman-Streiff syndrome is a rare congenital anomaly characterized by a peculiar bird facies, mandibular and maxillary hypoplasia, dyscephaly, cataracts, microphtalmia, hypotrichosis, skin atrophy, and short stature. Dental abnormalities are present in 80 percent of the cases and include malocclusion, crowding, severe caries, supernumerary and neonatal teeth, enamel hypoplasia, hypodontia, premature eruption of primary dentition, agenesis of permanent teeth, and anterior displacement or absence of condyles. Very few cases have been described in the dental literature. The predisposition to severe caries, together with other problems, makes it imperative that young patients be started in a strong prevention program as early as possible. This is a case report of a five-year-eleven-month-old white male who presented for a dental examination at The Children's Hospital in Denver, CO. The findings and recommendations for treatment are discussed.  相似文献   

6.
A 5-year-old Caucasian male presented with early loss of multiple deciduous teeth. All the characteristics were consistent with the diagnosis of regional odontodysplasia (ROD). Significant initial findings included premature loss of multiple primary mandibular teeth and some malformed permanent teeth. The affected teeth showed hypoplastic enamel and dentin, short roots, and wide pulp chambers, and were localized in the mandibular dentition. Treatment objectives for this patient were to provide improved esthetics, restored chewing function, and space maintenance by the construction of a temporary prosthetic restoration. However, with limited tooth support and an unusual occlusal pattern, it is difficult to obtain satisfactory retention and esthetics with traditional prosthetic techniques. In this article we introduce an alternative method for fabricating a custom removable denture and discuss the prognosis of the malformed permanent dentition and further treatment plan.  相似文献   

7.
The purpose of the study was to establish baseline values of the alveolar bone height of the primary molars and first permanent molars in sample of healthy U.S. seven- to nine-year-old children. Direct measurements of the distance from the cementoenamel junction (CEJ) to the alveolar crest (AC) on 223 pairs of bitewing radiographs from 223 subjects were made using a digimatic caliper under standardized conditions. The distance from the CEJ to the AC had medians from 0.58 mm to 1.39 mm (range 0.0 to 4.44 mm) for the primary molars and from 0.00 mm to 0.64 mm (range -1.35 to 2.15 mm) for the mesial aspect of the permanent molars. There were no statistically significant differences in the distance from CEJ to AC between teeth on the right and left sides of the mouth. The distances from CEJ to AC were always greater in the maxilla than in the mandible for similar primary molar sites, but only true for the mesial aspect of the permanent first molar at age nine. As a tooth is positioned more anteriorly in the mouth, the distance from CEJ to AC was greater. On the whole, males had greater distances than females and eight-year-olds had larger distances than seven- or nine-year-olds. Differences were observed in the measured distances for the different age and sex-groups and may be attributable to variations in eruption and exfoliation patterns. The distance was significantly greater in areas of interproximal restorations and open contacts, and there was a tendency for the distances to be greater in areas of interproximal caries.  相似文献   

8.
A 10.1-year-old boy showed no permanent teeth, with the exception of the lower central incisors. An x-ray examination revealed that eruption of the permanent dentition was obstructed by 1 deciduous supernumerary and 22 permanent supernumeraries ectopically. Treatment consisted of the following steps: (1) extracting all deciduous and supernumerary teeth; (2) waiting for the roots of the permanent teeth to develop and fitting two temporary partial prostheses; (3) assisting eruption of the permanent teeth by removing the bone that covers the remaining teeth and applying crowns to stimulate the eruption; and (4) bringing the permanent teeth into occlusion with orthodontic treatment. The problem of limiting treatment time was made more difficult by the amount of repositioning needed to bring the teeth into occlusion and by delayed root formation. Therefore the orthodontist decided to use extreme caution in applying forces; as a result, treatment time was lengthened. Success was due to good teamwork between the surgeon with an orthodontic background and the orthodontist, who was familiar with surgical procedures.  相似文献   

9.
The oral and dental abnormalities associated with a distinct variety of severe short-limb dwarfism are described. The patient, a 9-year-old Arab boy, had delayed development and eruption of teeth, severe oligodontia of permanent dentition, hypodontia, microdontia, supplemental incisor, enamel hypoplasia of primary teeth, doubled and abnormal frenal attachments, bifid uvula, hypoplastic maxilla, and malocclusion. Clinical and radiographic examinations revealed asymmetric dysplasia and anaplasia of long bones, craniofacial dysmorphia, prominent forehead, budlike fingers and bulbous toes, dysplastic nails, severe hearing loss, and reduced joint mobility. These features resemble, in general, those characteristic of Grebe chondrodysplasia, an extremely rare ill-defined syndrome that is inherited as an autosomal-recessive disorder.  相似文献   

10.
PURPOSE OF STUDY: To assess whether selected periapical radiographs, taken according to High Yield Criteria, can reveal as much intra-osseous pathology as universal panoramic screening. POPULATION STUDIED: The records of 1101 RAF recruits enlisted in 1988-89, average age 19 years (range 16-26). METHODS: The clinical records and bitewing radiographs of the recruits were examined and the requirement for periapical radiographs determined according to high yield criteria. A template, cut out to simulate the area covered by a periapical bitewing radiograph, was placed over the suspect region on the panoramic film and any findings found within the template recorded. The entire dental panoramic tomograph was then examined on a masked screen under 2X magnification and any further findings recorded. FINDINGS: There was a considerable number of findings reported, including three large isolated radiolucent areas, 75 periradicular radiolucent areas, four probable cysts and 1187 unerupted mandibular third molars. However, when the clinical significance of these 'lesions' was assessed only those related to dental causes appeared to have significant clinical implications and the results indicated that these could have been detected by selective radiology. CONCLUSION: This study showed that the only pathology which occurs frequently enough to justify radiographic screening of the jaws in young adults is related to teeth. It seems probable that this type of pathology can be at least as well detected by selective periapical screening, using high yield criteria, as is possible by universal panoramic screening.  相似文献   

11.
PURPOSE: To evaluate a dental adhesive system that uses a single conditioning/primer agent. MATERIALS AND METHODS: Twenty-five flat enamel and dentin bonding sites were prepared to 600 grit on human molar teeth. The Clearfil Liner Bond 2 adhesive system was used to bond Clearfil AP-X composite to both enamel and dentin. After 24 hours of water storage, shear bond strengths were determined using an Instron testing machine. Fifty V-shaped cavity preparations were prepared in human molar teeth with an enamel and cementum margin. Composite restorations were placed using the new adhesive system. The teeth were stored for 24 hours, thermocycled, stained with AgNO3 , sectioned and examined for microleakage. SEM examinations were also completed to evaluate the effects of the treatment steps on enamel and dentin surfaces. RESULTS: Mean shear bond strengths for the experimental adhesive to enamel and dentin were 28.2 +/- 4.9 and 19.4 +/- 3.1 MPa. A t-test revealed that the enamel bond strength was significantly greater (P<0.05) than the dentin strength. No marginal leakage was observed from the enamel margins of the restorations. Three restorations showed minimal leakage from the cementum margins. SEM examinations showed resin penetration into both the conditioned enamel and dentin surfaces. The adhesive system produced high bond strengths to both enamel and dentin, exhibited very minimal microleakage and was easy to use.  相似文献   

12.
Dentin dysplasia, type II (MIM*125420) is an autosomal dominant disorder of dentin development. Clinically the primary dentition appears opalescent, and radiographically the pulp chambers are obliterated, resembling dentinogenesis imperfecta. However, unlike dentinogenesis imperfecta, the permanent teeth in dentin dysplasia, type II are normal in color and, on radiographs, have a thistle-tube pulp chamber configuration with pulp stones. The similarity of the primary dentition phenotype suggested that the gene for dentin dysplasia, type II is allelic with the gene for dentinogenesis imperfecta, Shields type II (DGII; MIM*125490), which has been localized to chromosome 4q13-q21. Twenty-four members of a three generation family in which ten members are affected with dentin dysplasia, type II were genotyped for microsatellite alleles specific for the area of chromosome 4q linked to DGII. Linkage was assessed by using the LINKAGE computer program, assuming autosomal dominant inheritance, a disease allele frequency of 0.0001, and complete penetrance. The maximum two-point LOD score (Zmax = 4.2 at theta = 0.0) was obtained with SPPI and D4S2691. Multipoint analysis gave a maximum LOD score of 4.33. The candidate region for dentin dysplasia, type II is approximately 14.1 cM, includes SPPI, D4S2691, D4S2690, D4S451, and D4S2456, and overlaps the most likely location of the DGII locus. A candidate gene for DGII should also be considered a candidate gene for dentin dysplasia, type II.  相似文献   

13.
A family is reported with dentinal dysplasia type I affecting both dentitions. Presenting features included unusual mobility of the teeth, followed by early exfoliation; normal clinical shape of the crowns of the teeth, but with an amber color without any sign of attrition or abnormal loss of enamel. Radiographic findings showed pulp-chamber and root-canal obliteration, poor root formation, radiolucent linear appearance of the pulp chamber parallel to the cementoenamel junction and frequent periapical radiolucencies. Histological studies have reported large masses of calcified tubular dentin, atypical osteodentin, and also true denticle.  相似文献   

14.
White demineralized areas after the removal of orthodontic appliances remain a problem for clinicians and patients. The main objective of this study is to assess clinical photography as a method for the evaluation of caries and white spots and the in vivo study of remineralization of carious lesions. The secondary objective was to compare the effect of different levels of both experimental and commercial fluoride solutions on the remineralization of enamel carious lesions. White spot lesions were created with an acid solution on extracted permanent human teeth, and the lesions were remineralized in remineralizing solutions with or without fluoride ions. The changes in the enamel surface during the demineralization and the remineralization processes were recorded with a 35 mm clinical camera. Photographs were taken of the experimentally created white spots, the samples were sectioned for microradiography testing, and the actual mineral contents of the white spot lesions were calculated from the microradiographs. The enamel lesions were further analyzed by powder x-ray diffraction to confirm whether fluoride was incorporated into the lesions during the remineralization period. From this experiment it can be concluded: (1) clinical photography as currently practiced is not an adequate method of monitoring the remineralization of white spots with large lesion depths and (2) the experimental solution that contains 50 ppm fluoride had a higher efficacy for remineralization than the control solution or the commercial mouth rinse, which contained 225 ppm fluoride.  相似文献   

15.
The purpose of this study was to determine the effect of accidental dentin primer contact with etched enamel on shear bond strength of composite resin to enamel. Four dentin bonding systems were included in this study: GLUMA Dentin Bond, Scotchbond, and Prisma Universal Bond 2 and 3. Eighty extracted human permanent anterior teeth were used and divided in eight test groups. The vestibular surfaces were ground and acid etched. For each dentin bonding system 10 samples were treated with dentin primer prior to placement of resin. Shear bond testing showed that enamel contact with dentin primer in the above two systems decreased the shear bond strength between composite and enamel by 31 to 44%.  相似文献   

16.
OBJECTIVE: To investigate the distribution patterns of primary and permanent teeth in the cleft area and the numerical variation in teeth in unilateral complete cleft lip and palate (UCLP) patients. DESIGN: A survey of the dentition in UCLP patients. SETTING: Craniofacial Center, Chang Gung Memorial Hospital, Taipei, Taiwan. PATIENTS: 137 UCLP patients who met the following criteria: (1) have had at least one panoramic film taken, (2) the first panoramic film illustrates either primary or early mixed dentition. Evaluation of both permanent and primary dentition was available in 91 cases. MAIN OUTCOME MEASURES: Two evaluators performed independent evaluations of number and distribution of teeth in UCLP patients. The hypothesis that there are two odontogenic origins for maxillary lateral incisors was proposed to explain the occurrence of distribution patterns of dentition in the cleft area and to explain differences between primary and permanent dentition in UCLP patients. RESULTS: Four distribution patterns in the cleft area were identified in both the primary and the permanent dentition. In the primary dentition, placement of the lateral incisor distal to the alveolar cleft was the predominant pattern (pattern y, 82.4%), followed by absence of the cleft side maxillary lateral incisor (pattern ab, 9.9%), presence of one tooth on each side of the alveolar cleft (pattern xy, 5.5%), and placement of the lateral incisor mesial to the alveolar cleft (pattern x, 2.2%). In the permanent dentition, the most common pattern was the absence of the maxillary lateral incisor on the cleft side (pattern AB, 51.8%), followed by lateral incisor placement distal to the alveolar cleft (pattern Y, 46%), lateral incisor placement mesial to the alveolar cleft (pattern X, 1.5%) and the presence of one tooth on each side of the alveolar cleft (pattern XY, 0.7%). The discrepancy between the distribution patterns of primary dentition and permanent dentition successors is 57.1%. Variations in tooth number in both primary and permanent dentition of UCLP patients occurred most often in the cleft area. Abnormalities in the number of teeth (hypodontia or hyperdontia) outside the cleft area were more common in the permanent dentition than in the primary dentition (24.1% versus 4.4%). CONCLUSIONS: Four distribution patterns in the cleft area were identified in both sets of dentition. Our findings of distribution patterns in UCLP patients support the hypothesis that there may be two odontogenic origins for maxillary lateral incisors. Clinicians involved in managing the dentition of UCLP patients should consider the high frequency of numerical variation both in and outside the cleft area before starting dental treatment.  相似文献   

17.
The analyses of the pattern of dental disease in the Late Medieval Serbian population from cemetery excavations in the archaeological site Grachanica were based on the study of tooth wear, ante-mortem tooth loss, caries, hypoplasia, alveolar resorption, abscesses and calculus. The total sample of all available skeletons with almost complete permanent dentition numbers 45 individuals. Dental sample comprises 178 maxillary teeth and 337 mandibular teeth. The presence of dental caries was scored taking into consideration the size of the lesion (four degrees) and its position on the tooth. The degree of tooth wear was graded into one of four categories: atrition of enamel only; atrition involving dentin; atrition up to the level of fissure at the occlusal surface of the molar teeth, and exposure of the pulp chamber. The cystic defects within the alveolar bone were recorded according to their aetiology, size and position. Radiographic study had not been done in order to detect periapical destruction, so the presence of such destruction was recognizable in advanced stages associated with the appearance of fistula penetrating the compact alveolar bone usually at the buccal side. The condition of the alveolar crest resorption, as the evidence of periodontal disease, was graded into three categories, and the distance from the cemento-enamel junction to the alveolar crest was measured. The analysis of dental pathology profile consisted of the two reporting methods: individual count method (prevalence of disease based on the number of individuals affected) and tooth count method (distribution of lesions frequency on tooth type and class). The Grachanica dentition exhibits a dental pathology profile typical of agricultural medieval populations in this region. Tooth wear was the most frequent, affecting 95% of individuals. Dental caries and ante-mortem teeth loss exhibit also high frequency (51% and 69%). Dental pains of low prevalence include abscesses (13%) and enamel hypoplasia (20%). In the material examined, the carious process was responsible for pulp exposure to infection in all cases of abscess formation. The results obtained suggest that food processing technology and nature of diet allowed use of abrasive in the food and that oral hygiene was at the low level. On the other hand, there were not a lot of people who were subjected to stress-induced growth disruptures. The findings reported here contribute to understand how dietary change and life conditions are related to the changing patterns of dental diseases in medieval populations.  相似文献   

18.
Modern dental adhesive systems have improved the bond of restorative materials to mineralized tooth structures. The purpose of this study was to evaluate the clinical performance of composite restorations placed in abrasion and erosion lesions using the Clearfil Liner Bond dental adhesive system. Following ADA clinical guidelines for dentin and enamel adhesive materials, 62 facial class 5 smooth surface erosion or abrasion lesions with no undercuts and involving primarily root surfaces were restored in 25 adult male and female patients. The teeth were restored without preparations using Clearfil Liner Bond and Clearfil Photo Anterior composite resin. The clinical performance of the restorations was assessed by two examiners at baseline, 6 months, 1, 2, and 3 years using the following evaluative parameters: color match, marginal discoloration, and marginal integrity according to modified Ryge criteria; the presence or absence of recurrent decay; pre- and postoperative sensitivity; and restoration failure due to loss of retention or other causes. At the end of 3 years, four of the 55 restorations remaining in the study failed due to lack of retention (92.7% retention rate). The evaluations of the other clinical parameters demonstrated excellent performance by this system.  相似文献   

19.
Hypodontia, congenitally missing teeth is more common in permanent than primary dentition. The present investigation reports the prevalence and pattern of hypodontia in the primary and permanent dentitions, excluding third molars in a sample of Saudi children. The sample consists of 1,300 children, aged 5 to 10 years of age. Clinical and radiographic examinations were performed. The prevalence of children with hypodontia was found to be 2.6 percent. The mandibular second premolar was the tooth most frequently absent and account for 45 percent of the total missing teeth. In primary dentition, the maxillary lateral incisor was the tooth most frequently absent (9%). A peg-shaped permanent maxillary lateral incisor was present in 0.7 percent of the sample. Congenitally missing teeth were almost equally distributed between maxillary (52%) and mandibular (48%) arches.  相似文献   

20.
The effect of implanting autogenous and xenogenous (Bio-Oss) bone transplants into metabolically active sites within beagle dog mandibles during permanent premolar tooth eruption was examined. Ten 14-week-old beagles were used. Before commencing the radiographic experiments, metal bone markers were placed in the caudal margin of the mandible at the age of 10 weeks. The deciduous first and third molar teeth were extracted and their sockets over the permanent second and fourth premolars were implanted with autogenous particulate enchondral iliac crest bone, autogenous particulate membraneous mandibular body bone, xenogenous bovine anorganic bone mineral spongiosa granules (1-2mm3) (Bio-Oss, Geistlich Pharma, Switzerland) of left empty. The third premolar served as control site. Standardized oblique lateral radiographs were taken once a week. A number of coordinates of defined points and structures were determined by means of a coordinate digitizing system. Animals were killed 4, 10 and 16 weeks after bone transplantation for histological examination of the transplantation sites. All premolars showed no delay in eruption or disruption of crown and root development. On histology, the Bio-Oss particles were not resorbed or integrated in the alveolar bone but were pushed forward into the gingiva. We have demonstrated that there is on difference in the eruption curve of the permanent premolars in the four groups (ANOVA P > 0.5) and that bone transplantation has no inhibitory effect on eruption (ANOVA P > 0.3) and crown development of the underlying permanent premolar but that Bio-Oss does not have the same resorbable or integrating capability as autogenous bone grafts.  相似文献   

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