Fluoride content and recharge ability of five glassionomer dental materials

<p>Abstract</p> <p>Background</p> <p>The relationship between fluoride content and fluoride release for glass-ionomer cements is not well understood. The aim of this laboratory study was: to determine the fluoride concentrations at the surfaces of glass-ionomer materials with respect to different storage media and different pH environments; to examine the recharge ability of the materials after NaF immersion; and to assess the morphological changes at the material surfaces using scanning electron microscope and energy dispersive spectroscopic techniques (SEM/EDS).</p> <p>Methods</p> <p>Five glass-ionomer materials, Fuji Triage (FT), Fuji II LC (FII), Fuji VIII (FVIII), Fuji IX GP (FIX), and Ketac N100 (KN), were analyzed in this study. Resin-based fluoride releasing material Helioseal F (HSF) was used as a comparison material. The sample consisted of 120 cured cement disks (n = 20 disks of each tested material, 10 × 1.5 mm). Five disks of each material were stored in 4 different storage media (I- saline, II- acidic solution ph = 2.5, III- acid solution ph = 5.5, IV- NaF solution (c = 500/106). After 7 days, two disks of each material were transferred from media I, II and III to the NaF solution for 3 min. EDS analysis was conducted in 3 randomly selected spots of each experimental disk. SEM was used to determine morphological characteristics of the material surface. Differences between the experimental groups have been analyzed using Student's t-test with the level of significance set at p < 0.001.</p> <p>Results</p> <p>FT showed the highest fluoride content at the surface of the material. The lowest amounts of fluoride ions were detected at the surfaces of the FT disks stored at low pH environments, and this difference was statistically significant (p < 0.001). Glass-ionomers showed significantly higher fluoride concentrations when compared to the HSF (p < 0.001). After immersion in the NaF solution, fluoride concentrations at the surfaces of the disks increased when compared with previous storage media (FT>FVIII>KN>FII>FIX). SEM analysis of the surface morphology revealed numerous voids, cracks and microporosities in all experimental groups, except for KN and HSF. More homogenous material structure with more discrete cracks was observed in samples stored at neutral pH environment, compared to disks stored in acidic solutions.</p> <p>Conclusion</p> <p>The tested materials could be considered as promising dental materials with potential prophylactic characteristics due to their relatively high fluoride content, but also the ability to extensively reabsorb fluoride ions, especially in acidic environments.</p

The Hall Technique; a randomized controlled clinical trial of a novel method of managing carious primary molars in general dental practice: acceptability of the technique and outcomes at 23 months

<p>Abstract</p> <p>Background</p> <p>Scotland has high levels of untreated dental caries in primary teeth. The Hall Technique is a simplified method of managing carious primary molars using preformed metal crowns (PMCs) cemented with no local anaesthesia, caries removal or tooth preparation. This study compared the acceptability of the Hall Technique for children, their carers, and dentists, and clinical outcomes for the technique, with conventional restorations.</p> <p>Methods</p> <p>General dental practice based, split mouth, randomized controlled trial (132 children, aged 3–10). General dental practitioners (GDPs, n = 17) in Tayside, Scotland (dmft 2.7) placed conventional (Control) restorations in carious primary molars, and Hall Technique PMCs on the contralateral molar (matched clinically and radiographically). Dentists ranked the degree of discomfort they felt the child experienced for each procedure; then children, their carers and dentists stated which technique they preferred. The teeth were followed up clinically and radiographically.</p> <p>Results</p> <p>128 conventional restorations were placed on 132 control teeth, and 128 PMCs on 132 intervention teeth. Using a 5 point scale, 118 Hall PMCs (89%) were rated as no apparent discomfort up to mild, not significant; for Control restorations the figure was 103 (78%). Significant, unacceptable discomfort was recorded for two Hall PMCs (1.5%) and six Control restorations (4.5%). 77% of children, 83% of carers and 81% of dentists who expressed a preference, preferred the Hall technique, and this was significant (Chi square, p < 0.0001). There were 124 children (94% of the initial sample) with a minimum follow-up of 23 months. The Hall PMCs outperformed the Control restorations:</p> <p>a) 'Major' failures (signs and symptoms of irreversible pulpal disease): 19 Control restorations (15%); three Hall PMCs (2%) (P < 0.000);</p> <p>b) 'Minor' failures (loss of restoration, caries progression): 57 Control restorations (46%); six Hall PMCs (5%) (P < 0.000)</p> <p>c) Pain: 13 Control restorations (11%); two Hall PMCs (2%) (P = 0.003).</p> <p>Conclusion</p> <p>The Hall Technique was preferred to conventional restorations by the majority of children, carers and GDPs. After two years, Hall PMCs showed more favourable outcomes for pulpal health and restoration longevity than conventional restorations. The Hall Technique appears to offer an effective treatment option for carious primary molar teeth.</p> <p>Trial registration number</p> <p>Current Controlled Trials ISRCTN47267892 – A randomized controlled trial in primary care of a novel method of using preformed metal crowns to manage decay in primary molar teeth: the Hall technique.</p

Urinary catecholamine levels and dentofacial injuries in children

This study investigated the relationship between urinary catecholamine levels and dentofacial injuries in 221 children, boys and girls, aged 8 to 10 years. Dentofacial injuries were recorded by a questionnaire and a clinical examination. Three 24-h urine samples, taken with an interval of 1 year between each, were available for each subject. A representative urine sample from each examination was analyzed by the high-performance liquid chromatography technique to assay the catecholamine content. Socioeconomic factors were recorded by a questionnaire. Of the examined children 58 (24 boys and 34 girls) with complete 24-h urine samples showed neither historical nor clinical evidence of dentofacial injuries and constituted the control group. Two case groups, A and B, with historical and/or clinical evidence of dentofacial injuries were matched by age and gender. Differences in the quantitative and qualitative data were tested by the paired /-test and the %2 test, respectively, while a regression analysis was applied to measure the effects of norepinephrine on epinephrinc and dopamine. The 95% probability level was used. The results showed significant differences between control and case group A in the cpinephrine and norepincphrine levels of the second urine sample. Significant differences were also found between control and case group B at the first urine sample in epinephrine and dopamine and at the second in epinephrine. Injured boys had significantly higher values of all catecholamines except for epinephrine in the second urine sample than injured girls. The only significant difference found between boys and girls without dentofacial injuries was in norepinephrine in the second urine sample. The data suggested that children with dentofacial injuries are more frequently under emotional stress and consequently emotionally stressful children run a greater risk of sustaining such injuries. © Munksgaard, 1997

Urinary catecholamine levels in children with and without a history of dentofacial injuries

Abstract This study was conducted to investigate the existence of any differences in the urinary cathecholamine levels in children with and without a history of dentofacial injuries. Three hundred fourteen children, boys and girls, aged 6 to 8 years were included in this study. A questionnaire was distributed to the parents to collect information about the child&apos;s history of dentofacial injuries. A 24‐h urine sample was collected for each subject and a representative sample (25 ml) was analyzed by the HPLC technique to assay the catecholamine content. Of the examined children 68 (43 boys and 25 girls) had a history of dentofacial injury and constituted the experimental group. A control group of 68 children (43 boys and 25 girls) without a history of dentofacial injury w as matched by age and sex. The Student t‐test was used to identify any differences in urinary catecholamine levels between the two groups. The 95% probability was used. The results showed statistically significant differences in the mean values of epinephrine, while the differences in norepinephrine and dopamine were not significant. This study suggested that children with emotionally stressful states run a greater risk of having dentofacial injuries. Copyright © 1995, Wiley Blackwell. All rights reserve

Incidence of dentofacial injuries in children: A 2-year longitudinal study

In this prospective study the incidence of dentofacial injuries in 199 children aged 8 to 10 years was analyzed. Dentofacial injuries were recorded by a questionnaire and a clinical examination. After the first examination, each subject was re-examined at yearly intervals over a period of 2 years. Incidence rates were calculated in percentages and the chi-square was applied to test statistical differences. The 95% probability level was used. Results showed that the overall incidence of dentofacial injuries was 45.2%. The percentages for boys and girls were 28.6 and 16.6 respectively. The chi-square test showed significant gender differences, while differences by age were not significant. The highest incidence was recorded for dental injury followed by facial injury, historical evidence of injury and dental and facial injury

Multifactorial analysis of the aetiology of craniomandibular dysfunction in children

Objectives. It is generally accepted that the aetiology of craniomandibular dysfunction (CMD) is multifactorial. Different types of malocclusion, oral parafunctions especially bruxism, trauma of the mandible or temporomandibular joint (TMJ) and emotional stress are known aetiologic factors. Research has been conducted into the relationship between each of these aetiologic factors and the signs and symptoms of CMD. However, such an approach does not control for the simultaneous effect of other factors responsible for the development of the dysfunction. The purpose of this study was to investigate the effect of each aetiologic factor on the signs and symptoms of CMD in children, controlling for the effect of all other known factors by means of a multifactorial analysis. Methods. A sample of 314 children, aged 6-8 years, was examined clinically for signs of CMD and morphologic and functional malocclusion. Symptoms of CMD and oral parafunctions were recorded by the same investigator in an interview. Emotional stress was measured through urinary catecholamines including epinephrine, norepinephrine and dopamine, detected in a 24-h urine sample, using high performance liquid chromatography. A questionnaire was distributed to the parents to collect information regarding socioeconomic factors and the history of dentofacial injuries. A logistic multiple regression was carried out to estimate the partial effect of each aetiologic factor. A 95% probability level was used. Results. Posterior crossbite with lateral shift significantly affected the probability of child developing deviation of the mandible on opening. Similarly, posterior crossbite and epinephrine had a significant impact on TMJ tenderness, overjet had an effect on clicking, clenching and biting of objects had an effect on muscle tenderness, and lip/cheek biting influenced dysfunctional opening. Of the symptoms reported, pain on wide opening was affected significantly by lip/cheek biting. Conclusion. On the basis of these results, it can be suggested that parafunctional and some structural and psychological factors may increase the probability of the child developing the signs and symptoms of CMD

Etched glass ionomer liners: surface properties and interfacial profile with composite resins

The purpose of this study was to assess the surface alterations induced by acid etching on two glass ionomer lining cements (Ketac Bond, G‐C lining cement) and to evaluate their interface with a composite resin (Herculite XR) following various surface treatments. The changes in the surface composition and topography of the etched liners were studied by electron microprobe and ESCA analyses. The interfacial treatments performed on the ionomer surfaces were: (i) application of a bonding resin; (ii) 20‐s acid etching and application of a bonding resin; (iii) application of a dental adhesive based on a chlorophosphate ester of BisGMA (Scotchbond LC), without acid etching. The interfacial sealing efficiency of these treatments was studied by the silver nitrate microleakage technique combined with optical and electron microscopy. According to the results the etched surfaces of both the liners present excessive porosity with glass and matrix dissolution. Significant changes in the surface chemistry of the liners were detected indicating severe degradation. The microleakage study revealed interfacial gaps and fractures in the etched samples. The best results were obtained from the non‐etched ionomer liners which were subjected to the adhesive treatment. The efficiency of acid etching as a necessary step in the ‘layered’ technique is seriously questioned. Copyright © 1990, Wiley Blackwell. All rights reserve

Urinary Catecholamine Levels and Gingivitis in Children

THIS STUDY INVESTIGATED THE RELATIONSHIP between gingivitis and emotionally stressful states measured by the urinary catecholamines in children. Three-hundred and fourteen (314) children, boys and girls, aged 6 to 8 years were included in the study. Gingivitis was recorded by the gingival bleeding index and dental plaque by the plaque control record index. Proximal decayed surfaces, faulty restorations, and stainless steel crowns were diagnosed clinically and radiographically. Information concerning systemic and socioeconomic factors was collected by a questionnaire. A 24-hour urine sample was collected for each subject and analyzed by the HPLC technique to assay the catecholamine content. The multiple-regression analysis was carried out to test whether gingivitis was affected by the studied variables. The 95% probability was used. The results showed that epinephrine, norepinephrine, and dopamine did not have a significant association with gingival index. Dental plaque and proximal decayed surfaces significantly affected gingivitis. Of the socioeconomic factors, mother&apos;s education had a significant association with gingivitis when all factors were included in the analysis. The data suggest that emotionally stressful states may not increase the probability of developing gingivitis in children of this age

Porosity of pit and fissure sealants

The aim of this study was to investigate the bulk porosity of a range of pit and fissure sealants. The following materials were included in the study: Concise White Sealant and Delton (chemically cured); Delton (visible light‐cured); Helioseal, Visioseal and Prolite (visible light‐cured with delivery from the bottle via cannule): Delton, Luma Seal and Prisma Shield (visible light‐cured with syringe‐type direct delivery systems). Five cylindrical samples, 7 mm in diameter and 1 mm in thickness, were prepared from each sealant and the following parameters were analysed in a computer‐controlled mercury porosimeter: (i) total cumulative pore volume; (ii) specific surface area of pores; (iii) percentage total porosity (iv) bulk density; and (v) pore radius distribution. According to the results, the chemically cured sealants exhibited total cumulative pore volume, specific surface area of pores and total porosity. Significant differences were detected within the group of visible light‐cured materials. The visible light‐cured sealants with syringe‐type delivery exhibited the lowest porosity. Copyright © 1991, Wiley Blackwell. All rights reserve