Comparison of the failure rate, bonding time and ARI score of two orthodontic bonding systems: Self-Etch Primer and Conventional Etching Primer: A systematic review and meta-analysis

Experimental Bracket Design Performance on Bonding and Polymerization of Orthodontic Composite

Objective

To evaluate the enamel bonding ability and orthodontic adhesive resin degree of conversion using the experimental bracket design. Material and Methods. Thirteen bovine teeth were used in the study. The experimental bracket was modified with a translucent region in the center of its body. After enamel etching, Orthocem orthodontic adhesive (FGM, Joinville, Brazil) was applied on the bracket base for bonding. The groups were divided as follows (n = 10 per group): (1) control (CB) with standard brackets and (2) spot bracket (SB) with experimental brackets featuring a 0.8 mm translucent region at the center using carbide bur. Shear bond strength (SBS) was evaluated after 24 hours in a universal testing machine and adhesive remnant index (ARI). The degree of conversion (DC) was analyzed using Raman spectroscopy (n = 3 per group). Data were then analyzed using Student's t-test and Mann-Whitney statistical methods.

Results

The SB group exhibited a higher mean SBS (10.33 MPa) compared to the CB Group (8.77 MPa). However, there was no statistical difference between the groups (p = 0.376). Both SB and CB groups had a mean ARI score of 1. Raman analysis revealed a higher degree of conversion in the SB group (49.3%) compared to the CB group (25.9%).

Conclusions

The experimental support showed a higher degree of adhesive conversion, although there was no significant increase in bond strength.

Evaluation of shear bond strength and enamel remineralizing effect of experimental orthodontic composite containing nano-hydroxyapatite: An in vitro study

OBJECTIVE

The purpose of this study was to prepare an orthodontic composite containing hydroxyapatite nanoparticles to prevent demineralization and create a suitable environment for mineral deposition around orthodontic brackets, and to investigate the mechanical and remineralizing properties of the experimental adhesive composite.

METHODS

Experimental orthodontic composite were formulated using varying percentages of nano-hydroxyapatite particles. Assessments were based on four groups: a control group (3M™ Transbond™ XT) and experimental composites containing 2% (HA2), 5% (HA5) and 10% (HA10) hydroxyapatite. Vickers Microhardness test was performed to investigate the remineralizing effect in 3 stages: initial stage, after demineralization and after 4 weeks of exposure to artificial saliva. Scanning electron microscopy with energy dispersive X-ray spectroscopy analyser (SEM/EDAX) was used to evaluate hydroxyapatite precipitation and elemental composition of enamel surface. Shear Bond Strength tests were carried out using a universal testing machine and the debonding pattern was assessed using Adhesive Remnant Index (ARI).

RESULTS

All groups showed clinically acceptable SBS values. The highest SBS was achieved in the HA2 group, followed by Transbond™ XT, HA5 and HA10. There was no significant difference in the ARI scores. In terms of microhardness properties, HA5 and HA10 demonstrated a significant increase after 4 weeks. The results of SEM analysis showed the precipitation of hydroxyapatite crystals and EDAX analysis indicated the increase of calcium and phosphate ion peaks compared to the demineralized sample. The data were analysed using one-way ANOVA and Tukey's Post-hoc test.

CONCLUSIONS

Addition of hydroxyapatite nanoparticles to orthodontic composite can increase the mineral content and microhardness of the adjacent enamel. However, increasing the amount of nanoparticles reduces shear bond strength in a decreasing trend. The above-mentioned findings showed that incremental increase of nanoparticles of HA can be incorporated in composite to a certain extent and limitations are determined by mechanical properties (SBS) required for bracket bonding.

Evaluation of the shear bond strength and adhesive remnant index of color change, fluorescent, and conventional orthodontic adhesives: An in vitro study

AIMS

To investigate the in vitro performance of colour change orthodontic adhesive (CCOA) or fluorescent orthodontic adhesive (FOA), conventional orthodontic adhesives (COA), and the mixed CCOA and FOA utilizing the shear bond strength (SBS) and adhesive remnant index (ARI).

MATERIAL AND METHODS

Ninety extracted first premolars were used in the study. Four manufacturers of orthodontic adhesive were used, including Transbond™ XT (TBXT) and Transbond™ plus (TBP) (3M™ Unitek™, CA, United States), Ormco Enlight™ (OE) and Greengloo™ (GG) (Ormco™, CA, United States), Light Bond Medium™ (LBM), and GoTo™ (GT) (Reliance orthodontic products®, IL, United States), and BracePaste® Adhesive (BPA) and BracePaste® Colour Change (BPCC) (American orthodontics®, WI, United States). The mixed orthodontic adhesive of Transbond™ plus and GoTo™ (TBPGT) was prepared to evaluate the combined effect of colour change and fluorescent orthodontic adhesives. Peak SBS was recorded using a universal testing machine. ARI was measured using a stereomicroscope under 10x magnification. Descriptive statistical analysis and comparative tests were used to evaluate the results.

RESULTS

All CCOA and FOA had higher mean SBS than COA. The highest value of SBS was obtained in BPCC (23.56MPa), and the lowest value in TBPGT (11.41Mpa). One-way ANOVA multiple comparisons and Duncan's multiple range test showed that TBXT and TBPGT significantly differed in SBS with GT, GG, TBP, and BPCC, respectively (P=0.016). Kruskal-Wallis multiple comparisons test showed no significant differences in ARI among the tested adhesives (P=0.089).

CONCLUSIONS

Colour Change Orthodontic Adhesive (CCOA) and Fluorescent Orthodontic Adhesive (FOA) showed a higher SBS than conventional orthodontic adhesives. Greengloo^TM had the lowest ARI among the groups tested. All adhesives tested can be safely used in orthodontic practice, and both CCOA and FOA showed better performance than COA. The Transbond^TM plus and GoTo^TM (TBPGT) mixed adhesives showed the lowest performance in terms of SBS and ARI.

Reliability of qualitative and quantitative assessment of adhesive remnants after debonding of ceramic brackets bonded with Transbond™XT on human molar teeth: An in vitro study

OBJECTIVE

To test the hypothesis that there are any differences between qualitative and quantitative methods of adhesive remnants index (ARI) scores on the buccal surfaces of the upper molar.

MATERIALS AND METHODS

The study included 34 upper first human molars. After etching for 20seconds by using 35% orthophosphoric acid (Ultra-Etch, Ultradent Products Inc., USA) and then rinsed with distilled water for 15seconds, the adhesive (Transbond™XT, 3M™, USA) was applied and cured with the polymerization lamp (Bluephase Style, Ivoclar Vivadent, Liechtenstein) for 10seconds. Ceramic brackets (Damon® Clear™, Ormco, USA) were placed by composite (Transbond™XT, 3M™, USA) on the buccal surface of the molars. Following 24-hour storage of the samples in distilled water (WB-12, Phoenix Instrument, Gabsen, Germany) at 37°C, the brackets were debonded using a debonding plier (Damon Clear Debonding Plier, Ormco, USA). ARI and a modified ARI-scoring system were used. Three independent observers scored the ARI with the naked eye under 10x, 20x, and 32x magnifications using Stereomicroscope Stemi DV4 (Zeiss, Germany). Afterward, the digital microscope VHX-5000 (Keyence, Japan) under 50x magnification was used for the quantitative analysis of the adhesive remnants by just one evaluator. The Fleiss' Kappa-coefficient test was used to assess interrupter reliability.

RESULTS

Fleiss' Kappa-coefficient test show that the highest amount of agreement between observers is observed using the naked eye for both of the scoring methods P<0.001. Increasing the magnification led to the moderate decrease of inter-observer agreement. For evaluations with naked eye, a higher agreement is observed for the modified ARI score compared to the ARI scored. The agreement between the quantitative and qualitative evaluation of the ARI score rose with increasing magnification.

CONCLUSION

The assessment of adhesive remnants should be done either with naked eye or under 10x magnification, as they showed the highest rate of intra-observer agreement.

Clinical bracket failure rates between different bonding techniques: a systematic review and meta-analysis

BACKGROUND

Bracket failure increases the treatment time of orthodontic therapy and burdens patients with unnecessary costs, increased chair time, and possible new appointments.

OBJECTIVE

To compare the bond failures of different orthodontic materials based on the results of available clinical studies.

SEARCH METHODS

A systematic search of clinical trials was performed in the Cochrane, Embase, and Pubmed databases with no limitations. The list of investigated techniques contained conventional acid-etch primer (CM-AEP), self-etch primer (SEP), self-cure resin (SCR), and simple or resin-modified glass ionomer (RM-GIC) materials and procedures.

SELECTION CRITERIA

Clinical studies reporting the failure rate of bonded brackets after using direct adhesive techniques on buccal sites of healthy teeth were included.

DATA COLLECTION AND ANALYSIS

Bracket failure rates from eligible studies were extracted by two authors independently. Risk ratios (RRs) were pooled using the random-effects model with DerSimonian-Laird estimation.

RESULTS

Thirty-four publications, involving 1221 patients, were included. Our meta-analysis revealed no significant difference in the risk of bracket failures between SEP and CM-AEP. After 6, 12, and 18 months of bonding, the values of RR were 1.04 [95% confidence interval (CI), 0.67-1.61], 1.37 (95% CI, 0.98-1.92), and 0.93 (95% CI, 0.72-1.20), respectively. At 18 months, bracket failure was 4.9 and 5.2% for SEP and CM-AEP, respectively. Heterogeneity was good or moderate (I2 < 42.2%). The results of RM-GIC at 12 months indicated a 57% lower risk of bracket failure using SCR as compared with RM-GIC (RR: 0.38; 95% CI, 0.24-0.61). At 18 months, bracket failures for SCR and RM-GIC were 15.8 and 36.6%, respectively (RR: 0.44; 95% CI, 0.37-0.52, I2 = 78.9%), demonstrating three to six times higher failure rate than in the case of etching primer applications.

LIMITATIONS

A major limitation of the present work is that the included clinical trials, with no exceptions, showed variable levels of risk of bias. Another possible problem affecting the outcome is the difference between the clustering effects of the split mouth and the parallel group bracket allocation methods.

CONCLUSIONS AND IMPLICATIONS

The results revealed no significant difference between SEP and CM-AEP up to 18 months after application. RM-GIC had much worse failure rates than acid-etching methods; additionally, the superiority of SCR over RM-GIC was evident, indicating strong clinical relevance.

REGISTRATION

Prospero with CRD42020163362.

Bonding Failures of Lingual Orthodontic Brackets: A Retrospective Study Comparing Lingual Brackets with KommonBase Extensions, to Customized Lingual Brackets

The aim of the present study was to evaluate in a clinical setting the bracket survival of lingual brackets bonded with the KommonBase system, and to compare it to the survival of a customized lingual bracket system. Two convenience samples of 13 consecutive patients treated with lingual fixed appliances with KommonBase extensions (Group 1) and 14 consecutive patients treated with customized Incognito™ lingual fixed appliances were retrospectively enrolled (Group 2). First time debondings were recorded from the files. Data were submitted to statistical analysis and a Log-rank test was used to compare the Kaplan–Meier survival curves between the two groups. Statistical significance was set as p < 0.05. Lingual brackets bonded with the KommonBase system showed a failure rate of 8%, while Incognito brackets showed a failure rate of 7.1%. The Log-rank test comparing the Kaplan–Meier survival curves revealed no statistically significant difference between the two groups (p = 0.343). Most debondings occurred during the first 6 months. Upper incisors and canines were less prone to debond than premolars and molars. In conclusion, no difference in bracket survival was observed between the KommonBase system and a customized lingual appliance.