Huseyin Alkis

Effects of contamination by either blood or a hemostatic agent on the shear bond strength of orthodontic buttons

Objective To evaluate the effects of contamination by either blood or a hemostatic agent on the shear bond strength (SBS) of orthodontic buttons. Methods We used 45 freshly extracted, non-carious, impacted third molars that were divided into 3 groups of 15. Each tooth was etched with 37% phosphoric acid gel for 30 s. Human blood or the blood stopper agent was applied to the tooth surface in groups I and II, respectively. Group III teeth were untreated (controls). Orthodontic buttons were bonded to the teeth using light-curing composite resin. After bonding, the SBS of the button was determined using a Universal testing machine. Any adhesive remaining after debonding was assessed and scored according to the modified adhesive remnant index (ARI). ANOVA with post-hoc Tukeys test was used to determine significant differences in SBS and Fishers exact test, to determine significant differences in ARI scores among groups. Results ANOVA indicated a significant difference between groups (p < 0.001). The highest SBS values were measured in group III (10.73 ± 0.96 MPa). The SBS values for teeth in groups I and II were significantly lower than that of group III (p < 0.001). The lowest SBS values were observed in group I teeth (4.17 ± 1.11 MPa) (p < 0.001). Conclusions Contamination of tooth surfaces with either blood or hemostatic agent significantly decreased the SBS of orthodontic buttons. When the contamination risk is high, it is recommended to use the blood stopper agent when bonding orthodontic buttons on impacted teeth.

In vitro evaluation of shear bond strengths of colour change adhesives.

The aims of this study were to test whether the shear bond strengths (SBS) of three commercially available colour change adhesives (CCAs), Transbond Plus Color Change Adhesive, Grēngloo, and Blūgloo, are different and to compare their bond strengths with a traditional light cure adhesive, Light Bond. Forty-eight human permanent premolar teeth extracted for orthodontic reasons and without any caries or visible defects were used in this study. The brackets were bonded with Light Bond (group I), Grēngloo (group II), Blūgloo (group III), and Transbond Plus CCA (group IV). After bonding, the SBS of the brackets were tested with a Universal testing machine. Analysis of variance indicated a significant difference between groups I and IV (P < 0.001). No significant difference was found between groups II, III, and IV (P > 0.05). Adhesive remnant index (ARI) scores for all groups were not significantly different (P > 0.05). Significant difference existed between the SBS of Transbond Plus CCA and Light Bond. Although Transbond Plus CCA yielded the lowest SBS values, no statistically significant difference was found between bond strength values of the three commercially available CCAs. All three CCAs can be safely used in orthodontic practice since they yielded acceptable bond strengths. A higher incidence of ARI scores 4 and 5 revealed that bond failures in all test groups were mainly at the adhesive interface.

Effects of different intracoronal bleaching methods on shear bond strengths of orthodontic brackets

OBJECTIVE To evaluate the effects of different intracoronal bleaching methods on the shear bond strengths (SBS) of orthodontic brackets. MATERIALS AND METHODS Sixty freshly extracted mandibular incisors were randomly divided into four groups (n = 15 per group). After filling the root canals, root fillings were removed 2 mm apical to the cementoenamel junction, and a 2-mm-thick layer of zinc-phosphate cement base was applied. Group 1 served as the control. Intracoronal bleaching was performed with hydrogen peroxide (Opalacence Endo, Ultradent products Inc, South Jordan, Utah) in group 2, sodium perborate (Sultan Healthcare, Englewood, NJ) in group 3, and 37% carbamide peroxide (Whiteness Super Endo, Dentscare, ltda, Joinville, Brazil) in group 4. Orthodontic brackets were bonded with a light cure composite resin and cured with an LED light. After bonding, the SBS of the brackets was tested with a Universal testing machine. RESULTS Analysis of variance indicated a significant difference between groups (P < .001). The highest values for SBS were measured in group 1 (10.15 ± 1.15 MPa). The SBS was significantly lower in groups 2, 3, and 4 than in group 1 (P < .001). The lowest values for SBS were measured in group 3 (6.17 ± 0.85 MPa). SBS was significantly higher in group 4 than in group 3 (P < .05). CONCLUSIONS Intracoronal bleaching significantly affected the SBS of orthodontic brackets on human enamel. Bleaching with sodium perborate affects SBS more adversely than does bleaching with other agents.

Effects of fluorosis on the shear bond strength of orthodontic brackets bonded with a self-etching primer

The aim of this study was to compare the shear bond strength (SBS) of brackets bonded to fluorosed and non-fluorosed teeth with self-etching primer (SEP) and phosphoric acid (PA). The study involved 40 mildly fluorosed [Thylstrup-Fejerskov (TFT) Index = 1-3] and 40 non-fluorosed human premolar teeth. The fluorosed and non-fluorosed teeth were randomly divided into two subgroups. In the first subgroup, 37 per cent PA was applied for 30 seconds and in the second, a SEP (Transbond Plus) was used. The brackets were bonded with light-cure adhesive paste (Transbond XT) and cured for 20 seconds. The SBSs were measured after 1000 thermocyclies. Two-way analysis of variance, Tukeys multiple comparison test, and Weibull analysis were used for the evaluation of SBS values. Bond failure locations were determined with the adhesive remnant index (ARI) and were compared with the Kruskal-Wallis and Mann-Whitney U-tests. The mean SBS was 9.01 MPa for the fluorosed teeth bonded with SEP. This value was significantly different from those of fluorosed teeth etched with PA (15.22 MPa) and non-fluorosed teeth conditioned with SEP (12.95 MPa) and PA (15.37 MPa). The ARI scores of the fluorosed teeth conditioned with SEP were significantly lower than those of non-fluorosed teeth conditioned with SEP or PA. The results of this in vitro study suggest that there are no differences in the SBS of orthodontic brackets between mildly fluorosed and non-fluorosed enamel etched with 37 per cent PA for 30 seconds. The SEP showed lower SBS values for orthodontic brackets bonded to mildly fluorosed enamel. The findings provide some evidence that routine clinical use of a SEP to bond brackets to mildly fluorosed teeth cannot be supported.

Effects of different bleaching methods on shear bond strengths of orthodontic brackets

OBJECTIVE To evaluate the effects of different bleaching methods on the shear bond strength (SBS) of orthodontic brackets. MATERIALS AND METHODS Forty-five freshly extracted premolars were randomly divided into three groups (n = 15 per group). In group I, bleaching was performed with the office bleaching method. In group II, bleaching was performed with the home bleaching method. Group III served as the control. Orthodontic brackets were bonded with a light cure composite resin and cured with an LED light. After bonding, the SBS of the brackets were tested with a Universal testing machine. RESULTS Analysis of variance indicated a significant difference between groups (P < .001). The highest values for SBS were measured in group III (20.99 ± 2.32 MPa). The SBS was significantly lower in groups I and II than in group III (P < .001). The lowest values for SBS were measured in group II (6.42 ± 0.81 MPa). SBS was significantly higher in group I than in group II (P < .001). CONCLUSIONS Both of the bleaching methods significantly affected the SBS of orthodontic brackets on human enamel. Bleaching with the home bleaching method affected SBS more adversely than did bleaching with the office bleaching method.

Comparison of the effects of rapid maxillary expansion and surgically assisted rapid maxillary expansion in the sagittal, vertical and transverse planes

Objective: The aim of this study was to evaluate and compare the effects of rapid maxillary expansion (RME) and surgically assisted RME (SARME) in the sagittal, vertical, and transverse planes. Study design: Orthodontic records of 28 patients were selected retrospectively and divided into two treatment groups. Group 1 comprised 14 patients (4 boys, 10 girls, mean age 14.2 ± 0.74 years) who had been treated with RME. Group 2 comprised 14 patients (4 boys, 10 girls, mean age 19.6 ± 2.73 years) who had been treated with SARME. Measurements were performed on lateral and posteroanterior cephalograms and dental casts obtained before (T0) and after (T1) expansion. Results: Statistically significant differences were found in soft tissue convexity angle, anterior face height, and upper nasal width in group 1, and in U1–NA length and posterior face height measurements in group 2 (P<.05). In both groups significant increases were found in interpremolar, intermolar, maxillary, and lower nasal widths and in anterior lower face height (P<.01). Statistically significant intergroup differences were found in the ANB angle (P<.05) and maxillary intercanine (P<.01) measurements. Conclusion: With both RME and SARME, successful expansion of maxillary dentoalveolar structures and nasal cavity and palatal widening were achieved. Sagittal plane effects of SARME were similar to those of RME on dental skeletal and airway measurements. Key words: Surgically assisted rapid maxillary expansion, Rapid maxillary expansion, Airway, Transverse deficiency.

Physical properties of root cementum: Part 20. Effect of fluoride on orthodontically induced root resorption with light and heavy orthodontic forces for 4 weeks: A microcomputed tomography study

INTRODUCTION The major side effect of orthodontic treatment is orthodontically induced inflammatory root resorption. Fluoride was previously shown to reduce the volume of the root resorption craters in rats. However, the effect of fluoride on orthodontically induced inflammatory root resorption in humans has not yet been investigated. The aim of this study was to investigate the effect of high and low amounts of fluoride intake from birth on orthodontically induced inflammatory root resorption under light (25 g) and heavy (225 g) force applications. METHODS Forty-eight patients who required maxillary premolar extractions as part of their orthodontic treatment were selected from 2 cities in Turkey with high and low fluoride concentrations in the public water of ≥ 2 and ≤ 0.05 ppm, respectively. The patients were randomly separated into 4 groups of 12 each: group 1, high fluoride intake and heavy force; group 2, low fluoride intake and heavy force; group 3, high fluoride intake and light force; and group 4, low fluoride intake and light force. Light or heavy buccal tipping orthodontic forces were applied on the maxillary first premolars for 28 days. At day 28, the teeth were extracted, and the samples were analyzed with microcomputed tomography. RESULTS Fluoride reduced the volume of root resorption craters in all groups; however, this effect was significantly different with high force application (P = 0.015). It was also found that light forces caused less root resorption than heavy forces. There was no statistical difference in the amount of root resorption observed on root surfaces (buccal, lingual, mesial, and distal) in all groups. However, the middle third of the roots showed the least root resorption. With high fluoride intake and heavy force application, less root resorption was found in all root surfaces and root thirds. CONCLUSIONS Fluoride may reduce the volume of root resorption craters. This effect is significant with heavy force applications (P <0.05). The cervical and apical thirds of the root showed significantly greater root resorption after the application of buccal tipping force for 4 weeks.

Microleakage under orthodontic brackets bonded with different adhesive systems.

Objective: This in vitro study aimed to compare the microleakage of orthodontic brackets between enamel-adhesive and adhesive-bracket interfaces at the occlusal and gingival margins bonded with different adhesive systems. Materials and Methods: A total of 144 human maxillary premolar teeth extracted for orthodontic reasons was randomly divided into four groups. Each group was then further divided into three sub-groups. Three total-etching bonding systems (Transbond XT, Greengloo and Kurasper F), three one-step self-etching bonding systems (Transbond Plus SEP, Bond Force and Clearfil S3), three two-step self-etching bonding systems (Clearfil SE Bond, Clearfil Protectbond and Clearfil Liner Bond), and three self-adhesive resin cements (Maxcem Elite, Relyx U 100 and Clearfil SA Cement) were used to bond the brackets to the teeth. After bonding, all teeth were sealed with nail varnish and stained with 0.5% basic fuchsine for 24 h. All samples were sectioned and examined under a stereomicroscope to score for microleakage at the adhesive-enamel and adhesive-bracket interfaces from both occlusal and gingival margins. Statistical Analysis Used: Statistical analyses were performed with Kruskal-Wallis and Wilcoxon signed-rank tests. Results: The results indicate no statistically significant differences between the microleakage scores of the adhesives; microleakage was detected in all groups. Comparison of the average values of the microleakage scores in the enamel-adhesive and adhesive-bracket interfaces indicated statistically significant differences (P < 0.05). The amount of the microleakage was higher at the enamel-adhesive interface than at the bracket-adhesive interface. Conclusions: All of the brackets exhibited some amount of microleakage. This result means that microleakage does not depend on the type of adhesive used.

Effect of fluoride on root resorption following heavy and light orthodontic force application for 4 weeks and 12 weeks of retention

OBJECTIVE To evaluate the null hypothesis that fluoride intake via drinking water has no effect on orthodontic root resorption in humans after orthodontic force application for 4 weeks and 12 weeks of retention. MATERIALS AND METHODS Forty-eight patients who required maxillary premolar extractions as part of their orthodontic treatment were selected from two cities in Turkey. These cities had a high and low fluoride concentration in public water of ≥2 pm and ≤0.05 pm, respectively. The patients were randomly separated into four groups of 12 each: group 1HH, high fluoride (≥2 ppm) and heavy force (225 g); group 2LH, low fluoride (≤0.05 ppm) and heavy force; group 3HL, high fluoride and light force (25 g); and group 4LL, low fluoride and light force. Light or heavy buccal tipping force was applied on the upper first premolars for 28 days. At day 28, the left premolars were extracted (positive control side); the right premolars (experimental side) were extracted after 12 weeks of retention. The samples were analyzed with microcomputed tomography. RESULTS On the positive control side, under heavy force application, the high fluoride groups exhibited less root resorption (P  =  .015). On the experimental side, it was found that fluoride reduced the total volume of root resorption craters; however, this effect was not statistically significant (P  =  .237). Moreover, the results revealed that under heavy force application experimental teeth exhibited more root resorption than positive control groups. CONCLUSION The null hypothesis could not be rejected. High fluoride intake from public water did not have a beneficial effect on the severity of root resorption after a 4-week orthodontic force application and 12 weeks of passive retention.

Effects of sodium ascorbate and delayed bonding after bleaching on shear bond strengts of orthodontic brackets

Abstract Introduction: The aim of the study was to determine the effects of sodium ascorbate and delaying bonding for 4 weeks after bleaching on SBS of orthodontic brackets. Methods: Sixty freshly extracted, noncarious, premolars were randomly assigned to 4 groups of 15 each. Orthodontic brackets were bonded with a composite resin and cured with a halogen light. After bonding, the shear bond strengths of the brackets were tested with a universal testing machine. Group I served as the control. In groups II, III, and IV, teeth were bleached with an office bleaching method. In group II, brackets bonded immediately after bleaching. In group III, teeth were immersed in artificial saliva of 4 weeks after bleaching before bonding brackets. In group IV, teeth were treated with 10% sodium ascorbate after bleaching before bonding brackets. Results: One-way analysis of variance indicated a significant difference between groups (P < .001). The highest values for SBS were measured in group I (11.92 ± 0.81 MPa). The SBS was significantly lower in groups II, III, and IV than in group I (P < .001). There was no statistically significant difference between groups III and IV. Conclusions: Bleaching significantly reduced the SBS of orthodontic brackets on human enamel. If bleaching is mandatory, teeth should be treated with sodium ascorbate before bonding.