Prototype to measure bracket debonding force in vivo (original) (raw)
Related papers
Evaluation of the debonding strength of orthodontic brackets using three different bonding systems
The European Journal of Orthodontics, 2007
The aim of this work was to investigate the stability of the bracket-adhesive-enamel interface, as a function of adhesive material and of debonding procedure, in order to assess which debonding technique is the least detrimental to the enamel. Ninety lower adult bovine incisors were selected and metallic orthodontic brackets were bonded using three adhesive systems: Concise, Transbond, and Fuji Ortho. Three different debonding procedures were used based on tensile, shear, and torsional stresses. One-way analysis of variance statistical analysis was employed to compare mechanical properties, while the adhesive remnant index was used to evaluate fracture properties. Each adhesive material used showed a statistical difference in tensile failure. The difference between shear and torsion failure loads was statistically signifi cant only for the Fuji GC sample (P < 0.01). The shear test was the most damaging to the enamel surface. Transbond luting resulted in greater adhesion than the Concise or Fuji Ortho systems. Fuji Ortho was more prone to accidental debonding, while Transbond tended to cause enamel lesions, since high loads were required to debond the bracket. Of the three modes examined, torsional debonding stress resulted in the least enamel damage.
In vivo bracket bond strength using two adhesive systems applied under wet and dry conditions
Acta odontológica latinoamericana, 2006
The purpose of this study was to investigate, in vivo, the bond strength of two adhesive materials: a moisture insensitive primer (MIP)* and a one step self etching primer (SEP)*, both used with Transbond XT* on dry and wet enamel and an adhesion time of 10-15 minutes. First or second upper and/or lower bicuspids (n = 124), to be extracted for orthodontic reasons, were used. A comparison of the materials' behavior was conducted under four different situations: 1) MIP on enamel etched and dry; 2) MIP on a surface etched and wetted with patient's saliva; 3) SEP on a dry field, 4) SEP on a saliva-wet enamel. For statistical analysis, Dunn-Sidak's multiple comparison test was applied with a probability of less than 0.05 (before correction). Stainless steel brackets with mesh-backed pads were bonded to the teeth. Bond strength was tested with modified orthodontic pliers on which a strain-gage was fixed to measure handle deformation while debonding. Moisture insensitive primer...
BioMed Research International, 2021
Objective. To compare the orthodontic bracket debonding force and assess the bracket failure pattern clinically between different teeth by a validated prototype debonding device. Materials and Method. Thirteen (13) patients at the end of comprehensive fixed orthodontic treatment, awaiting for bracket removal, were selected from the list. A total of 260 brackets from the central incisor to the second premolar in both jaws were debonded by a single clinician using a validated prototype debonding device equipped with a force sensitive resistor (FSR). Mean bracket debonding forces were specified to ten (10) groups of teeth. Following debonding, Intraoral microphotographs of the teeth were taken by the same clinician to assess the bracket failure pattern using a 4-point scale of adhesive remnant index (ARI). Statistical analysis included one-way ANOVA with post hoc Tukey HSD and independent sample t-test to compare in vivo bracket debonding force, Cohen's kappa (κ), and a nonparametric Kruskal-Wallis test for the reliability and the assessment of ARI scoring. Results. A significant difference (p < 0:001) of mean debonding force was found between different types of teeth in vivo. Clinically, ARI scores were not significantly different (p = 0:921) between different groups, but overall higher scores were predominant. Conclusion. Bracket debonding force should be measured on the same tooth from the same arch as the significant difference of mean debonding force exists between similar teeth of the upper and lower arches. The insignificant bracket failure pattern with higher ARI scores confirms less enamel damage irrespective of tooth types.
Journal of Orthodontic Science, 2016
Objectives: To assess in vitro the quantitative and qualitative debonding behavior of the AEZ debonding plier, compared to shear debonding force, in debonding orthodontic metal brackets. Materials and Methods: Thirty-two extracted premolars bonded with metal brackets were randomly divided into two equal groups according to the type of simulated debonding method; compressive bond strength (CBS) group using AEZ debonding plier (Ormco Corporation, USA) attached to the Instron machine, and shear bond strength (SBS) group using regular Instron attachments. All teeth were subjected to debonding forces, and debonding strength was assessed. The buccal surfaces were then examined, under a stereomicroscope, and adhesive remnants were scored using adhesive remnant index (ARI). Debonding strengths comparison was performed using the independent sample t-test. ARI score comparison was performed using the Mann-Whitney U-test. Correlation between debonding strength and ARI scores was performed using the Spearman correlation. Results: There was no significant difference in mean debonding strength between the SBS (M = 6.17 ± 0.77 MPa) and CBS (M = 6.68 ± 1.67 MPa) groups (P > 0.05). The CBS group showed significantly less adhesive remnants than the SBS group (P < 0.05); 62.5% of CBS group had ARI score 1, whereas 68.8% of SBS group had ARI score 3. No significant correlation between ARI and debonding strength was found (P < 0.05). Conclusion: SBS was found to produce similar debonding strength to the AEZ debonding plier in vitro. However, the AEZ debonding plier resulted in less adhesive remnant which is of great advantage for reducing chair-time during cleanup after debonding brackets.
Progress in Orthodontics
Background: To introduce an orthodontic bracket debonding device capable of measuring debonding force clinically by a novel sensor mechanism Materials and method: A prototype orthodontic debonding device was constructed utilizing a lift-off debonding instrument (LODI) and force-sensitive resistor (FSR). For data interpretation, the force sensor was equipped with a microcontroller and C++ programming software running on a computer. Ninety-nine (99) 0.022-in. conventional metallic brackets were bonded to premolar teeth in vitro by a single clinician applying the same adhesive and bonding technique. For validation, the mean debonding force measured by the prototype debonding device (n = 30) and the universal testing machine (n = 30) was compared. Both intra-and inter-examiner reliability tests were done by holding and operating the device in a standardized manner. Following debonding by the prototype device, the bracket failure pattern was evaluated (n = 30) by adhesive remnant index (ARI) under the stereomicroscope at × 30 magnification. Statistical analysis included independent samples t test for validation and intraclass correlation coefficient (ICC) with a 95% confidence interval for both intra-and inter-examiner reliability. Results: Mean orthodontic bracket debonding force measured by the prototype device (9.36 ± 1.65 N) and the universal testing machine (10.43 ± 2.71 N) was not significantly different (p < 0.05). The prototype device exhibited excellent intra-[ICC (3, 1) = 0.942] and inter-examiner reliability [ICC (2, 1) = 0.921] and was able to debond brackets mostly at the bracket-adhesive interface. Limitation: Due to adjusting the position and mechanism of the force sensor, the device had to be held in a modified standardized position. Conclusion: A novel method of measuring in vivo orthodontic bracket debonding force has been introduced which proved to be validated, reliable, and safe in terms of enamel damage.
An Analysis of Incisive-Bracket Bond Resistance in Orthodontics I. General approach
2014
The aim of this study is to determine the bonding resistance of orthodontic brackets in accidental conditions i.e. bites from very hard materials which may occur in a normal activity. Many studies had been developed concerning the integrity of orthodontic systems and the strength of various pairs of brackets and adhesives in controlled conditions. In orthodontics many patients were returning to treatment, especially in the period immediately after the installation of orthodontic system as a result of failure of brackets. This failure is a consequence of patients’ natural habits on biting food despite medical recommendations. For this study bovine rib bone were used to simulate the human tooth and a certain pair adhesive-bracket. Pretests were developed in order to identify the behaviour of organic material and the results were satisfying. Unlike other studies in this study the shear resistance of the adhesive was analyzed using an universal testing machine with a load on the bracket...
Journal of Applied Biomaterials & Functional Materials
Aim: To evaluate the effect of simulated intraoral hydraulic, thermal, and mechanical stresses on the debonding characteristics of orthodontic brackets under different adhesive regimes. Materials and methods: Groups of pre-coated (G1) and non-coated (G2) orthodontic metal brackets were bonded onto the buccal surfaces of 96 premolars using etch-and-rinse (SG1, n = 24) and self-etch (SG2, n = 24) primers. Twelve specimens (C1) from each subgroup were subjected to early debonding resistance tests, while the other twelve (C2) were used to test delayed debonding resistance after exposure to conditions simulating intraoral hydraulic, thermal, and mechanical stresses. The debonding resistance of the brackets was evaluated using a universal testing machine and the debonding patterns were micro-visualized to determine the adhesive remnant indexes of subgroups of specimens. Results: Within each group, the etch-and-rinse primer (SG1) resulted in higher debonding resistance than self-etch prime...
American Journal of Orthodontics and Dentofacial Orthopedics, 2007
The purpose of this study was to measure and compare in-vivo and in-vitro bond strengths of orthodontic brackets bonded to human enamel and debonded at various times. An in-vivo debonding device was validated and used to measure bond strengths in the oral environment. Methods: For the in-vitro study, mini-twin metallic premolar brackets (Opti-mesh XRT, Oromco Corp, Glendora, Calif) precoated with Transbond XT composite resin (3M Unitek, Monrovia, Calif) were bonded to 60 extracted premolars. The teeth were divided into 4 groups of 15, and shear bond strength was tested on a universal testing machine at 4 time periods: 10 minutes, 24 hours, 1 week, and 4 weeks. For the in-vivo test, 60 premolars in 22 volunteers (dental students) from King Saud University were bonded with Mini-Twin metallic premolar brackets and divided into 4 groups; bond strengths were measured at 10 minutes, 24 hours, 1 week, and 4 weeks. Results: Statistical analysis with 1-way ANOVA at P Ͻ.05 showed no significant differences among the in-vitro or the in-vivo groups. Two-way ANOVA at P Ͻ.05 was used to compare the in-vitro results with the in-vivo results; the in-vivo group had significantly lower mean bond strength values. In addition, survival analysis, used to calculate the probability of bond failure at P Ͻ.05, confirmed the significant difference between in-vitro and in-vivo environments. Conclusions: Reported bond strength values are not time dependent.
Iranian Journal of Orthodontics, 2022
The aim of the in vitro study was to examine the enamel surface after the application of four different methods for adhesive removal following the bracket debonding procedure, as well as to compare their effects on enamel surface. Methods: Premolars (n=60) were randomly assigned to four groups. After initial debonding and recording the shear bond strength (SBS), adhesive remnant index (ARI) scores were assessed. The removal method for each of the four groups was the use of 1) a round bur, 2) rubber wheel bur, 3)12 fluted tungsten carbide bur, and 4) scaler. After that, teeth in all four groups were kept in artificial saliva for one month. After rebonding with a new bracket, again the SBS and ARI scores were measured. Two representative samples from each group were examined under a scanning electron microscope. ……. Pvalue <0.05 was considered as significant. ANOVA test was used to assess the SBS association within the group. Paired T test was used to assess the SBS between the group. fisher's exact test was performed to compare ARI index before and after. Results: There was significant decrease in secondary SBS value in group 1 but significant increase in secondary SBS value in group 3, and a slight decrease in SBS value in group 4. In SEM images, there were composite remnants in all the four groups with fewer remnants in group 2. Enamel surface damage was observed in the SEM image of group 3. ARI scores showed no significant difference. Conclusion: Adhesive remnant removal efficiency of the round bur and scaler are less. Rubber wheel bur is a good choice of instrument for removal of adhesive remnants from tooth surface as it does not affect the bond strength. Tungsten carbide bur shows good results, as secondary bonding SBS value increased. Significant difference between ARI scores did not exist, indicating a higher number of mixed type failure in all groups.