Evaluation of Glass-Ionomer versus Bulk-Fill Resin Composite: A Two-Year Randomized Clinical Study.

Background: The aim of this split-mouth design research was to compare the clinical performance of a glass-ionomer cement system on Class I/II cavities against the clinical performance of bulk-fill resin composite restoration materials. Methods: Thirty-five patients were randomized and enrolled in the study, aged between 10 and 12 years, all of whom had a matched pair of permanent mandibular carious molars with similar Class I/II. A total of 70 restoration placements were performed. The patients were each given two restorations consisting of either a glass-ionomer cement with a nano-filled coating or a bulk-fill resin composite after the use of a self-etch adhesive. The cumulative survival rates were estimated using log-rank test and the Kaplan−Meier method. For comparison of the restorative materials in line with the modified Ryge, the McNemar test and the Wilcoxon signed rank test were employed. Results: With regard to retention, the glass-ionomer cement system and bulk-fill resin composite performed similarly in permanent molars in Class I/II cavities over a period of up to 24-months (p > 0.05). Over the 24-month period, Class I restorations showed statistically better survival rates than Class II restorations (p < 0.05). In the case of glass-ionomer cement systems, over the two-year period, more common chipping and surface degradations were observed. Conclusions: The glass-ionomer cement system and bulk-fill resin composite restorative materials display good clinical performance over a period of 24-months.

Comparative evaluation of fluoride varnishes, self-assembling peptide-based remineralization agent, and enamel matrix protein derivative on artificial enamel remineralization in vitro.

BACKGROUND: One of the most unfavorable side effects of fixed orthodontic treatment is white spot lesions (WSLs). Although the most important approach is prevention of WSLs, it is also essential to evaluate the efficacy of the remineralization agents. However, there is no concurrence in the literature with respect to the remineralization process of these agents. The objective of the present study was to evaluate the effects of different fluoride varnishes, enamel matrix protein, and self-assembling peptide derivatives with varying chemical compositions on remineralization of artificially created WSLs in vitro using quantitative light-induced fluorescence (QLF). METHODS: Artificial WSLs were created on bovine enamel samples using acidic buffer solution (pH 5, 10 days). Specimens were randomly allocated to six groups (n = 10/group): (1) Emdogain (Straumann, Basel, Switzerland), (2) Curodont Repair (Credentis AG, Switzerland), (3) Duraphat (Colgate-Palmolive, New York, NY), (4) Clinpro XT (3 M ESPE, Pymble, New South Wales, Australia), (5) Enamel Pro Varnish (Premier Dental Products, PA, USA), and (6) control (untreated). The agents were applied to the WSLs according to the manufacturers' instructions. Fluorescence loss (ΔF), lesion area (area), and impact (ΔQ) values of enamel surfaces were quantified by QLF-D BiluminatorTM (Inspektor-Pro, Amsterdam, The Netherlands) at baseline and after 7, 14, and 21 days of application of the respective materials. RESULTS: ΔF value presented a significantly decreasing trend throughout the 21 days for all groups except the Duraphat and Enamel Pro varnishes. The changes between 14th and 21st days of the Clinpro XT varnish application were significantly higher than Emdogain, Curodont, and Enamel Pro. The Curodont group showed higher lesion area changes between the first and second week in comparison to the Emdogain, Clinpro XT, and Enamel Pro groups, whereas Clinpro XT assured the highest reduction from the second to the third week of the observation period. CONCLUSIONS: The fluorescence loss was significantly reduced with enamel matrix protein, self-assembling peptide, and light-curable fluoride varnishes in the analysis for 21 days. Curodont and Clinpro XT were effective in diminishing the fluorescence loss and lesion area compared to the Duraphat, Enamel Pro fluoride varnishes, and Emdogain in different time points.

Temperature-dependent erosivity of drinks in a model simulating oral fluid dynamics.

OBJECTIVES: Aim of this investigation was to study the temperature-dependent in vitro enamel erosion of five acidic drinks and citric acid under controlled conditions in an artificial mouth. METHODS: The erosive potential of Orange juice, Coca-Cola Zero, Sprite Zero, two fruit teas and citric acid (control) was investigated on bovine enamel specimens at temperatures between 5 °C and 55 °C. The pH values and total calcium content of all test drinks were determined. Specimens were immersed into an artificial mouth to imitate physiological oral conditions for 60 h. Cyclic de- and re-mineralization was performed, imitating the intake of six drinks in six h followed by a six-hour remineralization phase, where only artificial saliva ran over the specimens. Total erosive enamel loss was determined by contact profilometry. Differences in substance loss at different temperatures were tested for statistical significance (p-values ≤ 0.05) by means of ANOVA. RESULTS: Rising liquid temperature did not result in a considerable change of pH. Highest substance loss was observed for citric acid (33.6 ±â€¯6 µm to 38.7 ±â€¯6 µm), while only little erosion was induced by fruit tea (0.8 ±â€¯1 µm to 5.9 ±â€¯1 µm). Rising liquid temperature did not result in significantly increased substance loss for citric acid, orange juice and Coca-Cola Zero. Sprite Zero and both fruit teas, however, caused significantly (p < 0.001) more enamel loss at elevated temperature. CONCLUSIONS: Not all investigated drinks showed a temperature-induced change in erosivity. CLINICAL SIGNIFICANCE: For some erosive beverages it can be recommended to keep the consummation temperature as low as possible to decrease the risk of erosive tooth substance loss.

Color assessment after bleaching with hydrogen peroxide versus ozone: a randomized controlled clinical trial.

This randomized controlled clinical trial evaluated the color change of teeth bleached with either hydrogen peroxide (HP) or ozone (OZ). A total of 26 patients with a mean age of 36.2 years (SD, 8.7 years) who met the inclusion criteria were enrolled in the study. The subjects were randomly assigned to receive chairside bleaching using 40% HP or gaseous OZ. Maxillary dental arch vacuum trays were constructed with circumferential openings in the middle portion of the maxillary incisors at their labial surfaces. These trays were used for measuring color-first at baseline and then immediately and 48 hours after postbleaching-and were not used in bleaching. Changes in color were determined using CIE L*a*b* coordinates. Analysis of the data revealed that, while overall color change (ΔE*) values of the HP and OZ groups did not show statistically significant differences immediately after bleaching (P = 0.114), ΔE* values were significantly different 48 hours postbleaching (P = 0.00). Visible color changes were not obtained with either HP or OZ immediately postbleaching. The greatest visible color change occurred with HP 48 hours postbleaching.

Prevention of dentine erosion by brushing with anti-erosive toothpastes.

OBJECTIVE: This in vitro study aimed to investigate the preventive effect of brushing with anti-erosive toothpastes compared to a conventional fluoride toothpaste on dentine erosion. MATERIALS AND METHODS: Bovine dentine specimens (n=12 per subgroup) were eroded in an artificial mouth (6 days, 6×30 s/day) using either citric acid (pH:2.5) or a hydrochloric acid/pepsin solution (pH:1.6), simulating extrinsic or intrinsic erosive conditions, respectively. In between, the specimens were rinsed with artificial saliva. Twice daily, the specimens were brushed for 15 s in an automatic brushing machine at 2.5 N with a conventional fluoride toothpaste slurry (elmex, AmF) or toothpaste slurries with anti-erosive formulations: Apacare (NaF/1% nHAP), Biorepair (ZnCO3-HAP), Chitodent (Chitosan), elmex Erosionsschutz (NaF/AmF/SnCl2/Chitosan), mirasensitive hap (NaF/30% HAP), Sensodyne Proschmelz (NaF/KNO3). Unbrushed specimens served as control. Dentine loss was measured profilometrically and statistically analysed using two-way and one-way ANOVA followed by Scheffe's post hoc tests. RDA-values of all toothpastes were determined, and linear mixed models were applied to analyse the influence of toothpaste abrasivity on dentine wear (p<0.05). RESULTS: Dentine erosion of unbrushed specimens amounted to 5.1±1.0 µm (extrinsic conditions) and 12.9±1.4 µm (intrinsic conditions). All toothpastes significantly reduced dentine erosion by 24-67% (extrinsic conditions) and 21-40% (intrinsic conditions). Biorepair was least effective, while all other toothpastes were not significantly different from each other. Linear mixed models did not show a significant effect of the RDA-value of the respective toothpaste on dentine loss. CONCLUSION: Toothpastes with anti-erosive formulations reduced dentine erosion, especially under simulated extrinsic erosive conditions, but were not superior to a conventional fluoride toothpaste.

The effect of saliva substitutes on enamel erosion in vitro.

OBJECTIVES: To investigate the effect of saliva substitutes on enamel erosion in vitro. METHODS: A total of 204 bovine enamel samples were embedded in acrylic resin and allocated to 17 groups (n=12). The specimens were eroded in an artificial mouth (3 days; 6×30 s/days, flow rate: 2 ml/min) using citric acid (pH: 2.5). Immediately after the erosive attacks, saliva substitutes (12 sprays, 3 gels) were applied. Between the erosive cycles the specimens were rinsed with artificial saliva (flowrate: 0.5 ml/min). A SnCl2/AmF/NaF-containing mouthrinse was used as positive control, water spray served as negative control. Enamel loss was measured profilometrically and the data were analyzed using one-way ANOVA followed by Scheffé's post hoc tests (p<0.05). RESULTS: Four saliva substitutes increased enamel erosion, probably due to the low pH or the content of citric acid. Several saliva substitutes were able to reduce enamel erosion significantly by 60-90% (in the range of the positive control). The protective potential of these products was in the range of the positive control (reduction of enamel loss to 30% of negative control). The erosion-protective potential of these high-viscous products is probably related to their film-forming properties, leading to a mechanical protection of the surface. CONCLUSION: Saliva substitutes containing a very low pH exhibit a distinct erosive potential, while most high-viscous products present an erosion-protective effect. It can be recommended that patients suffering from xerostomia and at high risk for dental erosion should use high-viscous saliva substitutes, but should avoid saliva substitutes with low pH or containing citric acid. CLINICAL SIGNIFICANCE: It can be recommended that patients suffering from xerostomia and at high risk for dental erosion should use high-viscous saliva substitutes, but should avoid saliva substitutes with low pH or containing citric acid.

In vitro evaluation of the erosive potential of viscosity-modified soft acidic drinks on enamel.

OBJECTIVE: The objective of this in vitro study was to investigate the effect of viscosity-modified soft acidic drinks on enamel erosion. MATERIALS AND METHODS: A total of 108 bovine enamel samples (∅ = 3 mm) were embedded in acrylic resin and allocated into six groups (n = 18). Soft acidic drinks (orange juice, Coca-Cola, Sprite) were used both in their regular forms and at a kinetic viscositiy of 5 mm(2)/s, which was adjusted by adding hydroxypropyl cellulose. All solutions were pumped over the enamel surface from a reservoir with a drop rate of 3 ml/min. Each specimen was eroded for 10 min at 20 °C. Erosion of enamel surfaces was measured using profilometry. Data were analyzed using independent t tests and one-way ANOVAs (p < 0.05). RESULTS: Enamel loss was significantly higher for the regular (Coca-Cola, 5.60 ± 1.04 µm; Sprite, 5.49 ± 0.94 µm; orange juice, 1.35 ± 0.4 µm) than for the viscosity-modified drinks (Coca-Cola, 4.90 ± 0.34 µm; Sprite, 4.46 ± 0.39 µm; orange juice, 1.10 ± 0.22 µm). CONCLUSION: For both regular and viscosity-modified forms, Coca-Cola and Sprite caused higher enamel loss than orange juice. Increasing the viscosity of acidic soft drinks to 5 mm(2)/s reduced enamel erosion by 12.6-18.7 %. CLINICAL RELEVANCE: The erosive potential of soft acidic drinks is not only dependent on various chemical properties but also on the viscosity of the acidic solution and can be reduced by viscosity modification.

Does casein phosphopeptid amorphous calcium phosphate provide remineralization on white spot lesions and inhibition of Streptococcus mutans?

OBJECTIVE: The aim of this study was to evaluate the remineralization effect of Casein Phosphopeptid Amorphous Calcium Phosphate (CPP-ACP) on white spot lesions (WSL) and its inhibitory effect on Streptococcus mutans colonization. STUDY DESIGN: The study group consisted of 60 children exhibiting at least 1-WSL. Subjects were randomly divided into 2 groups: a test group of using CPP-ACP cream (Tooth Mousse, GC Europe N.V., Leuven, Belgium) and a control group using only fluoride containing toothpaste for a period of 3-months. Baseline WSLs were scored using DIAGNOdent device (KaVo Germany) and the saliva samples were collected to measure S. mutans counts. After the 3-month period the WSLs were again recorded and the saliva sample collection was repeated. Wilcoxon Signed Ranks Test was used for statistical analysis. RESULTS: DIAGNOdent measurements were increased by time (p = 0.002) in control group and no statistically significant diference (p = 0.217) was found in test group by the 3-month period. In both groups, the mutans counts were decreased in 3-month experimental period. CONCLUSIONS: These clinical and laboratory results suggested that CPP-ACP containing cream had a slight remineralization effect on the WSL in the 3-month evaluation period however longer observation is recommended to confirm whether the greater change in WSLs is maintained.

Effect of chlorhexidine varnish application on streptoococcus mutans colonisation in adolescents with fixed orthodontic appliances.

OBJECTIVE: The aim of this prospective study was to evaluate the re-colonisation pattern of Streptococcus mutans (MS) in highlevel MS-colonised patients with fixed orthodontic appliances following 40% chlorhexidine varnish application prior to bracket placement. MATERIALS AND METHODS: The subjects of this single-blinded clinical trial were 13-14year-old adolescents (N = 14) with significant orthodontic treatment need, a high salivary MS count but without any carious lesions. Baseline MS levels were determined by the cultivation of saliva collected from each subject using strips developed for this purpose (Strip-mutans, Orion Diagnostica, Espoo, Finland). Prior to the bonding of orthodontic brackets, 40% chlorhexidine varnish (EC 40, Explore, Nijmegen, Netherlands) was applied to all teeth for 10 minutes. The re-colonisation of MS was assessed at one, two, four and six week time periods. The data obtained were subjected to a repeated measures design. RESULTS: Chlorhexidine varnish reduced salivary MS significantly at the first, second and fourth weeks compared to baseline values. Significant MS suppression lasted less than six weeks and MS colonisation gradually returned to baseline level. CONCLUSION: Repeated application of chlorhexidine varnish in orthodontic patients with high MS levels may be beneficial throughout fixed appliance orthodontic treatment.

Antibacterial efficacy of prophylactic ozone treatment on patients with fixed orthodontic appliances.

OBJECTIVE: This study investigated the efficacy of ozone on microflora of patients with fixed orthodontic appliances. MATERIALS AND METHODS: Ten subjects undergoing fixed appliance therapy were enrolled in the study. Before any application, two elastic ligatures were removed with the aid of a sterile probe from the premolar brackets on the upper right and lower left jaws for baseline bacteriological counts. Then ozone gas was applied for 180 s by running the device on prophylaxis mode with included mouth tray according to the manufacturer's recommendations on all brackets. After the ozone application, two other elastic ligatures were removed from the opposite sides of the mouth of the patients. One week after the application two more elastic samples, which were not changed in the previous session, were collected from the upper right and lower left premolar brackets. The elastic ligatures were immersed in transfer solutions and cultured to determine the Streptococcus mutans and Lactobacillus acidophilus. Statistical analysis of the data was obtained by paired Student's t-tests. RESULTS: The ozone treatment reduced the S. mutans and L. acidophilus immediately after the application and these reductions were found to be statistically significant (p = 0.038 and p = 0.020). Both the S. mutans and L. acidophilus values increased by the 1-week period and the S. mutans values were significantly higher than the baseline values (p = 0.01). CONCLUSION: It can be concluded that the ozone treatment may have an instantaneous lethal effect on S. mutans and L. acidophilus; however, within the limitations of this study, a long-term preventive effect could not be observed.