Antibacterial and physical properties of resin modified glass-ionomers combined with chlorhexidine.

The purpose of this study was to determine the effect on mechanical properties and antimicrobial activity of the addition of chlorhexidine (CHX) to a resin modified glass-ionomer (Photac-fil, ESPE, Norristown, PA, USA). Chlorhexidine diacetate was combined with a resin modified glass-ionomer material at a concentration of 5%. The samples were tested for hardness, tensile strength and erosion at 24 h and 6-week intervals and for elution of CHX and antimicrobial activity weekly for 6 weeks. At 24 h there was no significant difference in hardness between the two groups, but at 6 weeks the resin modified glass-ionomer group was significantly harder than the CHX groups (P < 0.05). The diametral tensile strength test indicated no difference between the control and CHX groups at 24 h or at 6 weeks. The jet erosion test demonstrated significantly less erosion with the CHX group at 24 h but at 6 weeks the CHX group showed significantly more erosion than the control group. The chemical assay data demonstrated a peak elution of CHX at week 1 with residual amounts at weeks 2 and 3. The microbial data demonstrated that the CHX group had a significant reduction in Streptococcus mutans numbers for weeks 1-3, but after week 4 there was no difference between the glass-ionomer with and without CHX. The addition of CHX to resin modified glass-ionomer altered hardness and erosion of the resin-modified glass-ionomer, but because there are no material specifications, it is difficult to determine clinical implications. Chlorhexidine did significantly improve the antimicrobial effect of the glass-ionomer which was consistent with the chemical assay data. The results indicated that the addition of CHX to resin modified glass-ionomer material (Photac-fil) did not seriously degrade the physical properties during the time period tested and that the addition of CHX resulted in a greater reduction in S. mutans when compared with glass-ionomer alone.

Effect of restorative treatment on mutans streptococci and IgA antibodies.

PURPOSE: Streptococcus mutans has been implicated as the major causative agent of dental caries. Although restorative treatment for caries is thought to temporarily eliminate the carious challenge, there are few reports of alterations in salivary mutans streptococci (MS) numbers and no reports of changes in salivary IgA antibody to S. mutans following restorative treatment. METHODS: This study investigated the effects of treatment in 12 caries-active children. RESULTS: Numbers of MS decreased slightly from pre- to postrestoration levels in six subjects and increased in five subjects. However, there were no significant differences in pre-to postrestoration numbers of total oral streptococci, MS, the percentage of MS/total oral streptococci, salivary IgA antibody levels to S. mutans, or correlations between bacterial counts and IgA antibody levels. CONCLUSIONS: These results indicate that successful restorative treatment does not alter mutans streptococcal numbers and suggest the need for more effective methods for reducing the cariogenic challenge.

The effect of sleep on conscious sedation: a follow-up study.

This study evaluated the effect of preoperative sleep on the success of conscious sedation. Seventy-six children, from 18 to 61 months of age, participated in this study. Sixty-two children received chloral hydrate (50-60 mg/kg) and hydroxyzine (15-35 mg) and 14 children received intramuscular meperidine hydrochloride (2.2 mg/kg). Parents were asked to complete a questionnaire which asked several questions about their child's activity the previous day, and their bedtime. The operator ranked the sedations on a scale of 1 to 4, with 1 being good and 4 being poor. The results were statistically evaluated using the Wilcoxon Rank sum test. The children that received a normal amount or greater amount of sleep preoperatively did not show any significantly higher degree of success (p < 0.26) with their sedation appointment. The parents' perception of their child's tiredness did demonstrate borderline (p < 0.08) significance. Children greater than 36 months of age had a significantly higher (p < 0.03) degree of successful sedations. The results of this study demonstrated that there was no clear correlation between the child's preoperative sleep and the outcome of the sedation, but that a tired child may increase the likelihood of a poor sedation. In addition, the child's age at the time of the sedation may affect the outcome of the sedation.

The effect of sleep on conscious sedation.

This study evaluated the effect of preoperative sleep on the success of conscious sedation. Thirty healthy children between the ages of 18 and 61 months of age were utilized in this study. The children all received chloral hydrate (50-60 mg/kg) and hydroxyzine (15-25 mg) and nitrous oxide (30-50%). Parents were asked to complete a questionnaire which asked several questions about their child's activity the previous day, their diet, and questions that related to their bedtime. The operator ranked the sedations on a scale from 1 to 4 with 1 being good and 4 being poor. The results were then statistically evaluated using the non-parametric Mann-Whitney and Kruskal-Walls tests. The children that received a normal amount of sleep or greater amount of sleep preoperatively had a borderline (P = .06) higher degree of successful sedation. There was no correlation between the child's bedtime (early, normal, late) and the success of sedation. The parent's perception of their child's tiredness could not be correlated with the success of the sedation. The children greater than 36 months of age had a significantly (P = .02) higher degree of successful sedations. The results suggest that a well rested child may experience a more pleasant dental sedation while under chloral hydrate and hydroxyzine conscious sedation and that the child's age at the time of the sedation may affect the outcome of the sedation.

Properties related to strength and resistance to abrasion of VariGlass VLC, Fuji II L.C., Ketac-Silver, and Z-100 composite resin.

The purpose of this study was to evaluate the properties related to the strength and resistance to abrasion of new Type II lightcured glass ionomers, VariGlass VLC, and Fuji L.C., and to compare the results with Ketac-Silver and Z-100 composite resin. Each material was tested for strength with an Instron Universal Testing Machine and for resistance to abrasion with a motor-driven machine. The strengths of Z-100 were the highest. Among glass ionomers, Ketac-Silver had higher compressive strength, but lower diametral tensile and transverse strengths than the others; and Fuji II L.C. had higher strengths than VariGlass VLC. VariGlass VLC showed the greatest resistance to abrasion, followed respectively by Z-100, Fuji II L.C. and Ketac-Silver. ANOVA indicated significant differences in strengths and abrasion resistance, except, the volume losses of Fuji II L.C. and Ketac-Silver in the toothbrushing test were not significantly different (p < 0.01). The results support VariGlass VLC and Fuji II L.C. as alternative filling materials in Class III and V situations, but they are not recommended for stress-bearing restorations.

Analysis of orthodontic treatment by pediatric dentists and general practitioners in Indiana.

This investigation analyzed the extent of orthodontic services currently being provided by pediatric dentists and general practitioners in Indiana. All 71 Indiana pediatric dentists primarily in private practice and 500 general practitioners were mailed a survey/questionnaire. Sixty-two percent of the pediatric dentists and 17.9 percent of the general practitioners surveyed provided comprehensive orthodontic treatment, results much higher than those of previous surveys of pediatric dentists and general practitioners. Pediatric dentists were found to provide significantly more comprehensive orthodontic treatment and spend significantly more time providing orthodontic treatment than general practitioners, especially those in communities of less than 25,000. Sixty-three percent of the practitioners surveyed had taken some type of continuing education in orthodontics. These practitioners spent significantly (p less than 0.001) more time treating orthodontic conditions, and treated more complex cases than those who had not taken such courses.

Bonding strengths of etched porcelain discs and three different bonding agents.

Forty porcelain disks were resin bonded to etched base metal surfaces to measure tensile bond strengths. One metal surface was bonded to each porcelain surface, making each test specimen "sandwiched", with a porcelain disk between two metal surfaces. The mean bond strength values of the Conclude group was 3017 +/- 869 psi. The mean for the Mar-Bond group was 3747 +/- 693 psi, and the mean for the two Chameleon groups combined was 3172 +/- 544 psi. No two groups were significantly different.

The use of preformed acrylic veneers for the aesthetic treatment of severely discoloured anterior permanent teeth.

Laminate veneer resin systems have been advocated for aesthetic restoration of discoloured or malformed maxillary anterior teeth. A technique for providing such restorations has been described. Laminate veneer restorations have been proven as satisfactory interim restorations for young permanent teeth. Long term clinical studies are needed to better determine their cosmetic and physical durability as well as soft tissue compatibility.