Insulin effects on ouabain binding in A6 renal cells

OBJECTIVES: This study sought to identify risk markers associated with the provision of new restorations in children and to investigate whether the carious status of a tooth surface is associated with the restorative decisions of dentists. METHODS: A total of 911 schoolchildren in grades one, two, and three were randomly selected from the island of Montreal, Quebec, Canada. Dental examinations were carried out in 1990, 1991, and 1992. Tooth surfaces of first permanent molars were classified as sound, noncavitated, and cavitated. The carious status of a tooth was matched with restorative decisions reported to the insurance board. RESULTS: The presence of a carious cavity was a strong risk marker for placement of new restorations (odds rations > or = 4.11). After one year, less than 2 percent of sound tooth surfaces of first permanent molars were restored and about 21 percent of noncavitated tooth surfaces were restored. When new class I restorations placed in maxillary first permanent molars within 3-6 months after the baseline examination were evaluated, we found that between 73 percent and 86 percent of these new restorations were placed in sound or noncavitated tooth surfaces. A similar trend also was observed in mandibular first permanent molars. Poor agreement between epidemiologic diagnosis and restorative decisions was found. The restorative profile of dentists was a significant risk marker for placement of new restorations. CONCLUSION: The majority of new restorations in first permanent molars were placed in sound and noncavitated tooth surfaces because of the ubiquitous prevalence of these tooth surfaces and the validity problems of current caries diagnosis methods.     

Biosynthetic retrovectoring systems for gene therapy

The 5-year incidence of caries was studied in a random sample of 60-, 70- and 80-year-old inhabitants of G?teborg, with 69, 51 and 28 individuals in the different age groups. One aim of the study was to introduce a root caries index (DMFRS%) in which the missing root surfaces are taken into account. This study, as well as other recent studies, has shown that dental caries is the main reason for tooth extraction. The study also revealed that coronal and root caries occurred more frequently in elderly than younger people and the incidence of root caries was positively correlated with coronal caries (r = 0.3, p < 0.001) and negatively correlated with the number of remaining teeth (r = 0.4, p < 0.0001). The 5-year DMFRS% increment values increased with advancing age from 2.7 involved root surfaces per 100 susceptible ones in the 60-year-olds to 4.8 in the 70-year-olds and 10.7 in the 80-year-olds. It should be mentioned, however, that only people able to come to the clinic were enrolled in the study and an analysis of the attrition bias indicated that oral health may be worse in those who are too ill to participate. The frequent utilization of dental care among the participants was reflected in the finding of several new fillings and prosthetic crowns. Most of the very elderly people with carious lesions at baseline, however, had developed new lesions at the margins of the newly made restorations.     

Replacements of restorations in the primary and young permanent dentition

The present study focused on the type of restorative material used and the reasons for replacements of restorations in the primary and the young permanent dentition. All patients with restorations and who were 8 and 19 years of age in 1995 and were regularly treated at 11 Public Dental Health clinics in J?nk?ping County, Sweden, participated in the study. Data were extracted from the records for all types of restorations in canines and molars for the preceeding of 5 years for the 8-year-olds (i.e. from 3 to 8 years of age; n = 546) and for approximal restorations in premolars and molars for the preceeding 13 years for the 19-year-olds (i.e. from 6 to 19 years of age; n = 606). In all, 6012 restorations were evaluated. The two most common restorative materials used in the primary dentition were compomer and glass ionomer cement and in the young permanent dentition composite and amalgam. In the primary dentition, 29% of the restorations had been replaced and 4% of the teeth with restorations had been extracted. Thus, 33% of the restorations in the primary dentition failed. The corresponding figure for the young permanent dentition was 13%. The most common reason for replacements in the permanent dentition was secondary caries. That restorations often fail because of caries and that the development of secondary caries is not prevented by replacement of an old restoration indicate that more attention should be paid to preventive dental care for patients with restorations in the primary as well as in the young permanent dentition.     

Atraumatic restorative treatment and glass-ionomer sealants in a school oral health programme in Zimbabwe: evaluation after 1 year

An oral health care programme in secondary schools using the atraumatic restorative treatment (ART) technique for dental caries was started in 1993. Glass-ionomer was used as the restorative and sealant material. Sealants were placed using the "press finger' technique. Results after 1 year revealed a survival percentage for one-surface ART restorations of 93.4 whilst the complete and partial retention percentages for sealants were 60.3 and 13.4, respectively. No caries was observed in teeth restored using ART, and only 0.8% of surfaces diagnosed as having early enamel lesions at the start of the programme and sealed consequently had progressed into active dentinal lesions after 1 year. The sealant retention percentage and the survival percentage of ART restorations were influenced by an operator effect. The majority of restorations were carried out without administering local anaesthesia. The mean treatment time for one-surface ART restorations was 22.1 min (range per operator of 19.8-23.6 min), whilst the mean time for placing sealants was 9.4 min (range per operator of 8.2-10.8 min). Post-operative sensitivity was reported for 6% of the teeth restored. 95% of the students were satisfied with ART as a treatment modality. It is concluded that ART may in part be the answer to the unavailability of restorative care for many population groups globally.     

The prevalence and effectiveness of fissure sealants in Scottish adolescents

The presence of fissure sealants was recorded in 4294 adolescents during a 3-year, double-blind clinical caries trial, conducted in Lanarkshire, Scotland, between 1988 and 1992. Of 68,704 occlusal surfaces examined at baseline, sealants were detected on 7011 (10.2%) surfaces, in 1596 subjects. Of these, 17.4% were judged as incompletely sealed. At the final examination 24.3% of sealants originally recorded as complete were missing, with partial loss observed on a further 18.2% of surfaces. At that time, 21.4% of surfaces 'unsealed but sound' at baseline were recorded as decayed, filled or extracted due to caries, compared with 14.4% of surfaces on which an intact sealant had been recorded (P < 0.001). In contrast, of those surfaces on which the sealant was noted as deficient at the outset, 22.9% were judged to have been affected by caries. This study shows that sealants should be repaired when deficient if they are to be effective.     

Artificial caries formation around fluoride-releasing restorations in roots

Secondary caries is one of the most important factors leading to replacement of dental restorations. This investigation assessed the capacity of fluoride-releasing restorative materials to resist caries in vitro when used in roots. Class 5 cavities were prepared in the buccal and lingual surfaces of 30 extracted premolars. The six materials used were: glass-ionomer cement (Fuji), glass-ionomer cement with silver particles added (Ketac-silver), fluoride-containing composite resin (Tetric), composite resin (Silux plus), fluoride-containing amalgam (Fluor-Alloy) and high-copper amalgam (Dispersalloy). After 5 weeks in an acid gel for caries-like lesion formation, the teeth were sectioned longitudinally and examined with polarized light. The results showed that repair with glass-ionomer materials of a carious lesion may be of great importance in the prevention of secondary caries around the restorations in roots.     

Antenatal sonographic diagnosis of club foot with particular attention to the implications and outcomes of isolated club foot

OBJECTIVE: This study assessed the clinical performance of dentin-bonded crowns, in which ceramic crowns are bonded to underlying dentin with a resin composite-based luting material and a dentin bonding agent. METHOD AND MATERIALS: Twenty-five patients who had received such restorations more than 1 year previously were recalled for evaluation of their crowns. RESULTS: Sixty dentin-bonded complete-coverage restorations were assessed. Forty-one of the crowns had been placed on incisor teeth. The mean time since placement of the restorations was 2.43 years. Fifty-seven of the 60 restorations were intact. The three failures had resulted from cracks in the restorations, which had not clinically debonded. No secondary caries was detected at the crown margins, and anatomic form was assessed as excellent for 56 crowns. Root canal treatment had been required in one case. Color match was rated very good for 47 crowns. All 25 patients were satisfied with their restorations. CONCLUSION: Dentin-bonded crowns may be found to have a low rate of failure and to provide a high level of patient satisfaction.     

Caries diagnosis with dye-staining at amalgam restoration margins

PURPOSE: To determine the strength of agreement between detection of caries at the margin of amalgam restorations with a caries detector dye, and detection of caries histologically utilizing light/polarizing light microscopy. MATERIALS AND METHODS: 17 permanent molars with intact amalgam restorations, determined to be caries-free by visual inspection and explorer probing, cleansed with an air/water/abrasive slurry system, and with evidence of amalgam enamel marginal staining from application of a 1% solution of sulforhodamine B caries detector dye were utilized. Longitudinal, undecalcified sections, 80-100 micrometers thick, were prepared including stained and unstained regions of the amalgam/enamel margin of each tooth, providing 34 margins for study. The sections were examined in the light/polarizing light microscope for evidence of marginal caries. The Kappa Index was calculated to determine the strength of agreement between the caries dye method and the light/polarizing light microscopic method of caries diagnosis. RESULTS: Microscopically, caries was detected in 14 of 34 margins (41%). Agreement for presence of caries was 5 of 34, and for absence of caries 8 of 34 (total agreement 38%). 12 of 17 dye-stained margins were microscopically caries-free, and 9 of 17 unstained margins had caries microscopically. Kappa Index for these findings was 0.23, indicating poor strength of agreement.     

Root caries in a sample of elderly persons

With the anticipated increase in the aged adult population and the associated gingival recession, the prevalence of root caries is expected to increase. The purpose of this study was to determine the experience and distribution of root caries in a group of aged adults living in Kayelitsha. All non-institutionalized elderly black adults participating in a community geriatric programme were examined. Root caries was recorded using visual and tactile criteria and expressed as the root caries index (RCI) rate. The mean age of the subjects was 65.2 years, the mean number of teeth present was 17.3 and the mean RCI rate was 2.2 per cent. All subjects had gingival recession while only 23.8 per cent had root caries. No surfaces with restored root caries lesions were found. In the maxilla the highest RCI rate was observed on the interproximal surfaces of the posterior teeth (4.4 per cent) but in the mandible the buccal surfaces of the posterior teeth had the highest RCI rate (4.2 per cent). In both the maxilla and the mandible the lingual surfaces of the anterior teeth showed no root caries. Maxillary teeth did not have a significantly higher root caries attack rate than mandibular teeth. Root caries does not appear to be a public health problem in the sampled population.     

Translation, adaptation and validation process for the DINA instrument. Derdiarian Information Needs Assessment

The 5-year incidence of dental caries in a random sample of 60-, 70- and 80-year-old inhabitants of Goteborg was related to salivary and microbial conditions. Of the 208 persons examined at baseline, 148 (71%) participated in the follow-up examination; 69, 51 and 28, respectively, in the different age groups. The study revealed that 27% of the participants had not developed any carious lesions during the 5-year period and that the incidence of coronal and root caries increased with age. In the 60-year-olds, 2.5% of the susceptible coronal and root surfaces, respectively, had decayed, while the corresponding figures for the 80-year-olds were 8.8% for coronal surfaces and 9.8% for root surfaces. In all, 18% had an unstimulated saliva secretion rate of below 0.1 ml/min and 14% had a stimulated secretion rate of <0.7 ml/min, with a mean rate which decreased with increasing age from 2.0 to 1.6 and 1.3 ml/min (p = 0.02). The overall salivary counts of lactobacilli and mutans streptococci, particularly the subspecies of Streptococcus sobrinus, had increased during the period. In the respective age groups of 60, 70 and 80 years, 15, 39 and 39% had a mutans streptococci count of > or = 10(6) CFU/ml in saliva and the corresponding figures for > or = 10(5) lactobacilli counts were 22, 31 and 43%. In the stepwise regression analysis, it was found that age, salivary levels of mutans streptococci and lactobacilli and number of teeth were the best predictors of the incidence of root caries. In conclusion, these observations indicate that there is an increased risk of dental caries with age owing to unfavourable microbial and salivary conditions.     

Tunnel restorations. A 3 1/2-year follow up study of Class I and II tunnel restorations in permanent and primary teeth

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.     

A randomized, controlled trial of a behavioral intervention to prevent sexually transmitted disease among minority women

Using annual bite-wing radiographs, the incidence and progression of approximal caries (4d-7m) were assessed longitudinally in teenagers and adolescents whose treatment had been based on remineralizing rather than restorative strategies. A closed cohort of 536 children initially was followed from 11 to 22 years of age. The scoring system was: 0 = no visible radiolucency; 1-2 = radiolucency in the enamel up to the enamel-dentin border; 3 = radiolucency with a broken enamel-dentin border but with no obvious progression in the dentin; 4 = radiolucency with obvious spread in the outer half of the dentin, and 5 = radiolucency in the inner half of the dentin. Caries rates were estimated as the number of new lesions/100 tooth surface-years, and the Kaplan-Meier estimate was used to calculate the cumulative survival time of each approximal surface. Three events were used: the transitions from states 0 to 2, 2 to 4 and 3 to 4. The results showed a considerable variation between the surfaces in both caries rates and survival time. For all surfaces combined, the median caries rate from state 0 to 2 was 3.9 new lesions/100 tooth surface-years; from state 2 to 4, the rate was 5.4, and from state 3 to 4 it was 20.3. Of the sound surfaces (state 0), 75% survived 6.3 years without reaching state 2. Given state 2, 75% survived 4.8 years without reaching the outer half of the dentin (state 4), while given a lesion at the enamel-dentin border (state 3), 75% survived 1.3 years without doing the same. The median survival time of lesions from state 3 to 4 was 3.1 years. The group with DMFSappr>1 at the age of 11-12 years had a risk of new approximal enamel lesions (state 0-2) that was 2.5 times greater than that of the group with DMFSappr = 0-1.     

Porcelain veneers for primary incisors: a case report

A 4-year-old boy with severely discolored primary maxillary incisors was treated with bonded porcelain veneer restorations. Two years previously, the child had been treated with topical application of sodium fluoride-silver nitrate solution to arrest dental caries associated with a nursing bottle habit. With minimal chair time, the incisors were restored with laboratory-processed porcelain veneer restorations that were bonded with resin cement. This is perhaps the only report to date of the use of porcelain veneer restorations for primary anterior teeth.     

Influence of finishing and polishing procedures on the decision to replace old amalgam restorations: an in vitro study

The purpose of this study was to establish the influence that finishing and polishing of existing amalgam restorations might have on the decision to replace them. Forty extracted teeth, in which amalgam restorations had been placed in vivo, were individually examined by 60 practitioners and students prior to and following standard finishing and polishing procedures. Examiners, who had not been informed of the study's methodology or objective, opted either for maintaining or replacing the restoration in question. The main reasons for replacement were also registered. Finishing and polishing significantly reduced the number of decisions to replace restorations in all groups and for all practitioners. "Appearance" (anatomic shape) was the most frequently cited reason for replacing restorations before finishing and polishing, followed by marginal defects and secondary caries.     

Ten-year longitudinal clinical evaluation of a visible light cured posterior composite resin

Using modified USPHS criteria, we evaluated annually for ten years 91 cases restored with visible light cured posterior composite resin LFP (Base resin: UDMA; filler: micro crushed type, alumino-silicate, barium glass and silica, 85 wt%, 74 vol%). The 91 cases restored with LFP decreased to 68 in ten years. Of the 23 cases that were lost, one resulted from a pulpal reaction immediately following restoration, four were extracted owing to periodontal disease or extrusion of third molars, two became abutments owing to loss of an adjacent tooth, eight had recurrent caries, and eight were lost owing to caries on a surface having no relationship to the composite resin restoration. Because we observed comparatively little wear, good marginal adaptability, and no discoloration, we concluded that the ten-year clinical success of LFP was on the whole very good, and that this resin has adequate clinical merit as a restorative material for posterior teeth when restricted to restorations covering comparatively small areas.     

2-year clinical evaluation of a gallium restorative alloy

PURPOSE: To assess the clinical performance of 2-year old gallium alloy restorations. Parameters evaluated include: (1) fracture at the margins, (2) tarnish, (3) surface roughness, (4) tooth fracture, (5) fracture through the body of the restoration, and (6) any medical or dental conditions arising during the study. MATERIALS AND METHODS: Nine patients received 30 Class I restorations of Galloy gallium alloy. These were placed as conservatively as possible under a rubber dam. Fifteen of the preparations were lined with a Bis-GMA resin to seal the restoration from moisture. The other 15 preparations were sealed with Amalgambond. After placement of the gallium alloy, the exposed surfaces of all restorations were sealed with the Bis-GMA resin, and the occlusion was checked. The restorations were examined at 2 weeks, 3 months, 6 months, 1 year and 2 years. RESULTS: At the 2-year recall, all restorations were intact with the exception of one tooth fracture (cause unknown). Forty-five percent of the restorations exhibited tarnish and 60% had a rough surface. The fracture at the margins of these restorations was minimal, and no significant difference could be found between those using Amalgambond and those sealed with the resin system. No medical problems were reported by the patients, and postoperative sensitivity was minimal.     

Effects of a 12-month prophylactic programme on selected oral bacterial populations on root surfaces with active and inactive carious lesions

In 15 caries-active patients, with a total of 770 exposed root surfaces, the effect of fluoride therapy and professional tooth cleaning was studied during a 1-year period. Dental plaque from 92 of the root surfaces and whole saliva samples were analysed at baseline and after 12 months for the presence of specific bacteria. The results showed that the number of active carious lesions had decreased from 99 to 46, while the inactive lesions had increased from 69 to 124. Of the active lesions which had been converted into inactive lesions, most were on the buccal and fewest were located on the distal surfaces. Lower plaque scores were found on sound and inactive root surfaces compared to active surfaces. The salivary concentrations of mutans streptococci and lactobacilli remained constant during the 12-month observation period. There was a tendency for higher levels of Streptococcus mutans in plaque from active lesions compared with sound root surfaces, whereas an inverse relationship was noted for the Streptococcus oralis group. No significant differences in the Actinomyces naeslundii counts were detected. In conclusion, the 12-month prophylactic programme had an effect on the clinical surface characteristics of root caries, but the components of the oral microflora selected for study seemed to be relatively unaffected during the observation period.     

The use of liners under amalgam restorations: an in vitro study on marginal leakage

OBJECTIVE: Marginal leakage of amalgam restorations may lead to secondary caries and pulpal damage. The purpose of this study was to determine the effect various cavity liners might have on microleakage. METHOD AND MATERIALS: Mesio-occlusodistal amalgam restorations with margins on enamel and dentin were treated with different liner materials (an adhesive system, a topical fluoride gel, a cavity varnish, and a glass-ionomer cement) in vitro. Following restoration, the teeth were submitted to thermocycling in a stained solution and sectioned to allow assessment of microleakage. RESULTS: On enamel, the control group (no liner) and the glass-ionomer-lined group had equivalent leakage scores and were superior to every other group. On dentin, only the glass-ionomer specimens had superior performance. The cavity varnish and fluoride-lined specimens exhibited the highest leakage scores. CONCLUSION: The use of liners does not reduce microleakage on amalgam restorations when the cavity margins remain on enamel. On dentin margins, a glass-ionomer liner can reduce microleakage.     

In vitro inhibition of caries around a resin composite restoration containing antibacterial filler

Class V cavities were prepared and restored with resin composite containing antibacterial filler powder (Apacider-AW, Ap-AW) using experimental restorations. The restored teeth were incubated in vitro with the cariogenic bacteria Streptococcus mutans IFO 13955. Ground sections were then prepared and examined using macrophotography. Lesions of the outer and inner wall were noted, and the depths of which the lesions penetrated were measured. We found that, in restorations containing 1-5 wt% Ap-AW, caries penetrated the marginal area, while in restorations containing 10 wt% Ap-AW the margin remained free of caries out to a distance of about 1.1 and 1.8 mm on the occlusal and gingival sides, respectively.     

The epidemiology of Neisseria gonorrhoeae isolates in Greenland 1979-1990: the emergence, spread and disappearance of non-PPNG strains carrying the conjugative 38.9 kb plasmid

The aim of this study was to compare the clinical performance of an amalgam, a glass polyalkenoate (ionomer) cerment material and a resin-based composite material used in small Class II cavities in permanent teeth. All restorations were inserted under rubber dam. They were examined yearly for 3 years. One clinician continued the study up to 5 years. The clinical examination focused on two criteria: clinically acceptable and failure. In addition, impressions were taken of the prepared cavities immediately before restoration and at each clinical examination using an elastomeric material. The study comprised 274 Class II restorations (88 amalgams, 95 cerments and 91 resin composites) placed in 142 adolescent patients. One hundred and sixty-seven restorations were in molar and 107 in premolar teeth. Patient dropout after 5 years resulted in the loss of 161 restorations, evenly distributed for restorative material and type of tooth involved. Four amalgam restorations, 22 glass ionomer cerment and nine resin composite restorations failed. The glass ionomer cerment and amalgam restorations failed primarily due to bulk fractures, while the resin composite restorations failed due to secondary caries and bulk fractures.