Effect of saliva contamination on bracket failure with a self-etching primer: a prospective controlled clinical trial

Bracket Bond Failures: Incidence and Association with Different Risk Factors-A Retrospective Study

BACKGROUND

Bracket bonding failure is one of the relevant problems in fixed orthodontics therapy, which affects the total treatment and quality of treatment results. The purpose of this retrospective study was to evaluate the frequency of bracket bond failure and find out risk factors.

METHODS

A total of 101 patients with an age range of 11-56 years were included in this retrospective study and treated for a mean period of 30.2 months. Inclusion criteria were: males and females with permanent dentition and completed orthodontic treatment in both fully bonded dental arches. Risk factors were calculated using binary logistic regression analysis.

RESULTS

The overall bracket failure rate was 14.65%. The bracket failure rate was significantly higher in the younger patients' group (p = 0.003). In most cases, patients experienced bracket failures in the first month of the treatment. Most of the bracket bond failures occurred on the left lower first molar (29.1%) and were twice as common in the lower dental arch (66.98%). Patients with increased overbite had an increased likelihood of bracket loss (p = 0.042). Class II malocclusion increased the relative risk of bracket failure, while Class III decreased the rate of bracket failure, but the difference was not statistically significant (p = 0.093).

CONCLUSIONS

The bracket bond failure rate was higher in younger patients than in older patients. Brackets placed on mandibular molars and premolars had the highest failure rate. Class II was associated with an increased bracket failure rate. Increased overbite statistically significantly increases bracket failure rate.

Comparison of self-etch primers with conventional acid-etch technique for bonding brackets in orthodontics: a systematic review and meta-analysis

BACKGROUND

Bonding with self-etch primers (SEPs) is one of the most popular systems for attaching orthodontic brackets to the enamel surface. There are conflicting reports about the efficacy and success of these systems compared with acid-etch (AE) bonding.

OBJECTIVE

This systematic review and meta-analysis was performed to compare SEP with conventional AE technique for bonding brackets in fixed orthodontics.

SEARCH METHODS

Articles related to the subject of interest were searched in electronic databases, including PubMed, ISI Web of Science, Scopus, EMBASE, and Cochrane's CENTRAL, from inception to 2 June 2021. Search for grey literature, and hand search for relevant studies were also performed.

SELECTION CRITERIA

Based on the PICO model, randomized clinical trials using full-arch bonded fixed orthodontic appliances comparing SEP and conventional AE systems were included in the review process.

DATA COLLECTION AND ANALYSIS

After assessing the risk of bias, data from the included studies were extracted using custom piloted forms. Inverse-variance random-effects meta-analyses were performed to combine the results of bracket failure, adhesive remnant index (ARI), and bonding time.

RESULTS

Nineteen randomized clinical trials were included in the systematic review and 17 randomized clinical trials [5 parallel-group (PG) and 12 split-mouth (SM) studies] were included in the meta-analysis. No significant difference in bracket failure at 6 months [risk ratio (RR) = 1.50, P = 0.26, 12 SM] and (RR = 0.68, P = 0.34, 2 PG), 12 months (RR = 1.6, 8 SM) and (RR = 1.17, P = 0.54, 2 PG), and ≥18 months (RR = 0.84, P = 0.31, 3 SM) and (RR = 1.20, P = 0.3, 3 PG) between SEP and AE groups could be found. Also, ARI score was similar between different bonding systems [mean difference (MD) = -0.44, P = 0.06, 4 SM]. The bonding time per tooth was faster in the SEP group (MD = -26.55, P < 0.001, 2 SM) and (MD = -24.00, P < 0.001, 2 PG).

LIMITATIONS

inclusion of three studies with a high risk of bias and high amount of inconsistency between the results of individual studies were the biggest limitations of our review.

CONCLUSIONS

The bracket bonding failure and ARI score were not significantly different between self-etch and conventional AE bonding systems. The bonding time was lower for the SEP, but some other requirements for SEPs like pumice prophylaxis could diminish this advantage.

REGISTRATION

The protocol for this systematic review was registered at PROSPERO with the ID CRD42021248540.

A Clinical Comparison of Failure Rates of Metallic and Ceramic Brackets: A Twelve-Month Study

Objective

Clinical comparison of the survival rates between stainless steel and ceramic brackets over a 12-month period.

Materials and Methods

The study involved 20 consecutive patients with diagnosed malocclusion that required two-arch fixed appliance treatment. The participants were randomly divided into two 10-member groups. Group 1 was treated with Abzil Agile (3M Unitek) stainless steel brackets; group 2 was treated with Radiance (American Orthodontics) monocrystalline ceramic brackets. All the brackets were bonded by the same operator. Over the next 12 months, all bracket failures were recorded with each appointment. The received data were processed statistically using the Mantel–Cox test, Kaplan–Meier method, and Cox hazard model.

Results

A total of 381 brackets were bonded, 195 of which were metallic brackets and 186 were ceramic ones. In the 12-month observation period, there were 14 metal (7.2%) and 2 ceramic bracket (1.1%) failures. The overall failure rate was 4.2% (n = 16). The majority of failures (14 brackets; 87.5%) occurred during the first 6 months of the experiment, 12 (83%) of which were metal brackets and 2 (100%) were ceramic brackets. The statistical analysis revealed significant differences between the groups (p < 0.05).

Conclusions

Metal brackets demonstrated significantly higher failure rates than ceramic brackets for both 6- and 12-month observation periods (p < 0.05). The 6% difference between the brackets is clinically significant as it corresponds to one additional failure within 12 months.

Microleakage of a Self-Adhesive Flowable Composite, a Self-Adhesive Fissure Sealant and a Conventional Fissure Sealant in Permanent Teeth with/without Saliva Contamination

Objectives:

Application of fissure sealants is a practical method for prevention of occlusal pit and fissure caries. Microleakage is an important factor affecting the success of fissure sealant treatment. This study aimed to assess the microleakage of a self-adhesive flowable composite, a self-adhesive fissure sealant and a conventional fissure sealant in permanent teeth with/without saliva contamination.

Materials and Methods:

This in vitro, experimental study evaluated 108 extracted human third molars, which were randomly divided into six groups (n=18) of control, Denu-Seal conventional fissure sealant applied on etched enamel with/without saliva contamination, Vertise Flow self-adhesive flowable composite applied on rinsed and dried enamel with/without saliva contamination and Prevent Seal self-adhesive fissure sealant applied on rinsed and dried enamel with/without saliva contamination. Microleakage was assessed using the dye penetration technique and subsequent observation of samples under a stereomicroscope. Data were analyzed using the Kruskal-Wallis and Tukey’s test.

Results:

Microleakage of the conventional fissure sealant with/without saliva contamination was significantly lower than that of other groups (P<0.05).

Conclusion:

Microleakage of the conventional fissure sealant is less than that of self-adhesive fissure sealant and self-adhesive composite, irrespective of saliva contamination.

Comparative evaluation of sealing ability, penetration and adaptation of a self etching pit and fissure sealant- stereomicroscopic and scanning electron microscopic analyses

Background

The efficacy of pit and fissure sealants in preventing occlusal caries is a well-established fact. Considering the difficulty in achieving strict isolation for a longer duration while treating the pediatric patients, a simplified procedure of sealant application is desirable. While, a self-etching sealant, Prevent Seal offers a quick procedure, the physical properties of this material haven’t been studied yet. Thus, this study was aimed to comparatively evaluate sealing ability, penetration and adaptation of a self-etching pit and fissure sealant and a conventional resin sealant.

Material and Methods

This was an in vitrointergroup comparative study, which consisted of 2 groups- Group I (Conventional acid etch sealant, Clinpro) and Group II (Self etching sealant, Prevent Seal). Out of 32 selected teeth 16 were used to study microleakage, with the help of dye penetration test using Övrebö and Raadal criteria. Remaining 16 were used to evaluate sealant penetration and adaptation viz bubbles in the bottom of fissure, debris in the fissure, tags in the bottom of the fissure and tags at cuspal slopes and fissure entrance was done using stereomicroscope. Post stereomicroscopic evaluation 4 samples each were randomly chosen from both the groups and checked for etching pattern using Scanning electronic microscope.

Results

The comparison of tested properties between the groups was done using Chi square test. There was no statistically significant difference observed when microleakage and sealant penetration / adaptation properties were compared between two groups (p=0.63 and p= 0.131, 0.131, 0.302, 0.106 respectively). No conclusive results could be withdrawn while etching patterns were compared between the groups (p=0.717).

Conclusions

The self-etching sealant Prevent seal was found to have similar microleakage, sealant penetration and adaptation properties as conventional acid etch sealant.

Key words:Pit and fissure sealant, self-etching, scanning electron microscope, sealing ability.

Effect of the Time of Salivary Contamination during Light Curing on Degree of Conversion and Microhardness of a Restorative Composite Resin

Saliva contamination is a major clinical problem in restorative procedures. The purpose of this study was to evaluate the effect of the time of salivary contamination during light curing on the degree of conversion and the microhardness of a restorative composite resin. Eight groups of 10 samples for measuring the microhardness and eight groups of 5 samples for evaluating the degree of conversion were prepared. The samples of each group were contaminated with human saliva at a certain time. The first group (T0) was contaminated before light curing. The specimens in groups T2–T30 were contaminated at 2, 5, 10, 15, 20 and 30 s after the start of light curing, respectively. The samples of group T40 were contaminated after light curing. The degree of conversion and the microhardness of the specimens were measured by Fourier transform infrared (FTIR) spectroscopy and Vickers hardness testing techniques, respectively. The results of this study revealed that there were no significant differences between the groups in terms of the degree of conversion of the composite resin. Consistent with the findings for the degree of conversion, significant differences in the microhardness between the groups were not found. In conclusion, from a clinical point of view, the results of our study showed that the time of salivary contamination (before, during or after light curing of composite resin) has no significant effect on the polymerization (degree of conversion) and one of the important mechanical properties of dental composite resins (microhardness).

The effect of various adhesives, enamel etching, and base treatment on the failure frequency of customized lingual brackets: a randomized clinical trial

Objectives

The aim of this paper was to compare failure differences in precious metal customized lingual brackets bonded with three adhesive systems. Also, differences in failure of non-precious metal brackets with and without a silicatized base layer bonded with the same adhesive, as well as the influence of enamel etching prior to using a self-etching dual cure resin were explored.

Materials/methods

Five different groups were defined in a semi-randomized approach. Group 1 (IME): Maxcem Elite with 378 Incognito brackets and etched teeth, Group 2 (IMNE): Maxcem Elite with 193 Incognito brackets on non-etched teeth, Group 3 (INE): Nexus+Excite with 385 Incognito brackets, Group 4 (IRE): Relyx with 162 Incognito brackets, Group 5 (HRME) and Group 6 (HNRME): Maxcem Elite with 182 Harmony brackets with silicatized and non-slicatized bases respectively. Bracket failures were recorded over a 12-month period.

Results

The number of failures during the observation period was small in the various adhesives types of groups, as well as in HRME and HNRME groups, and the comparisons among those groups were non-significant (P > 0.05). A statistically significant difference (P < 0.05) was found between the IME and IMNE groups.

Conclusions

1. During the first year of treatment customized lingual brackets failure frequencies (rates) are not different for the three adhesive materials tested. 2. Eliminating the etching stage when using self-etch/self-adhesive adhesives, may lead to a dramatic increase in the failure rates. 3. Silicoating of stainless steel customized lingual brackets does not seem to influence the failure of the bonds.

Incidence of orthodontic brackets detachment during orthodontic treatment: A systematic review

OBJECTIVES

To evaluate the incidence of orthodontic brackets detachment during orthodontic treatment.

METHODS

Using electronic databases; eligible studies up to January 2018 were retrieved, independently reviewed, and screened. The Coleman Methodology Scoring System (CMS) and Cochrane Collaboration's tool were used to assess quality and risk of bias in the included studies.

RESULTS

Of the seventeen studies included in the final synthesis, thirteen were categorized as randomized clinical trials (RCTs), one prospective cohort and retrospective survey each, whereas two studies could not be categorized. The number of patients in the selected studies ranged between 19 and 153; the mean age was between 10.5 to 38.7 years, and male to female ratio was 353:495. Almost all studies had a high risk of bias, and more than half of the studies had CMS score of 70 or above. The numbers of brackets examined in the studies ranged between 361 and 3336. The incidence of brackets detachment ranged from 0.6 to 28.3%.

CONCLUSIONS

The incidence of brackets detachment during orthodontic treatment is high.

Effects of a self-etching primer and 37% phosphoric acid etching on enamel: a scanning electron microscopic study

OBJECTIVE

The purpose of this study was to compare the etching effects of a self-etching primer with 37% phosphoric acid on enamel by using a scanning electron microscope. Bond strength and the site of bond failure were also determined for brackets bonded using SEP and 37% phosphoric acid.

MATERIALS AND METHODS

A total of 60 maxillary premolar teeth were used for this study and they were divided into four groups. First two groups were used for studying the different types of etch patterns obtained and the next two groups were used to test the bond strength with the help of Universal testing machine. After debonding, the amount of residual adhesive was assessed according to adhesive remnant index using a stereomicroscope.

RESULTS

The majority of etch patterns obtained in the 37% phosphoric acid group were type II, whereas in the SEP group, type IV pattern was more common. There was no statistically significant difference between mean bond strengths obtained with the SEP group and the phosphoric acid group. Use of SEP results in less amount of residual adhesive on tooth surface after debonding.

CONCLUSION

SEP produces more conservative etch pattern compared to 37% phosphoric acid. Use of SEP for bonding provides similar and clinically acceptable bond strength compared to use of 37% phosphoric acid etching technique and requires less clean-up procedures hence, reduces enamel loss.

CLINICAL SIGNIFICANCE

Use of 37% phosphoric acid for orthodontic bonding yields high bond strength but, causes enamel loss during both etching and debonding. SEPs not only provide adequate bond strength with a more conservative etch pattern but also enable easy debonding, thereby reducing the enamel damage.

Effect of different methods for decontaminating tooth enamel after contact with blood before bonding orthodontic buttons

PURPOSE

To evaluate the best method for decontaminating tooth enamel contaminated by contact with blood before bonding orthodontic buttons.

MATERIALS AND METHODS

The labial surfaces of 195 bovine incisors initially received prophylaxis, followed by 37% phosphoric acid etching, adhesive application, and light polymerization. After this, the labial surfaces of all teeth were contaminated with blood. The teeth were then randomly divided into 13 groups (n = 15), comprising the control group (treated according to the manufacturer's recommendations) and 12 experimental groups treated by the following decontamination methods: group 1, no decontamination; group 2, washing with distilled water; group 3, washing with physiologic solution; group 4, jets of air; group 5, gauze; group 6, cotton wool; group 7, distilled water plus jets of air; group 8, distilled water plus gauze; group 9, distilled water plus cotton wool; group 10, physiologic solution plus jets of air; group 11, physiologic solution plus gauze; and group 12, physiologic solution plus cotton wool.

RESULTS

No statistical differences were shown between the control group and groups 4, 7, 10, and 11 (P > .05). The lowest bond strength values were shown in group 1, in which no decontamination was performed, and groups 6 and 12, which were decontaminated with cotton wool and physiologic solution plus cotton wool, respectively.

CONCLUSIONS

The best method of decontaminating enamel contaminated with blood is washing with physiologic solution, followed by drying with jets of air and gauze or drying with jets of air only.

Shear bond strength of rebonded brackets after removal of adhesives with Er,Cr:YSGG laser

This study was conducted to examine the bond strength of rebonded orthodontic brackets after adhesive residuals on the surface of the bracket bases were removed by Er,Cr:YSGG lasers. Seventy-six brackets bonded to premolars with a self-etching primer adhesive system were equally divided into four groups after the first debonding with the bracket bases (Group 1) untreated, and treated by (Group 2) Er,Cr:YSGG laser, (Group 3) sandblaster, and (Group 4) Er,Cr:YSGG laser/sandblaster. The treated brackets were rebonded to the new premolars in the same manner as the first-stage experiment. The shear bond strengths were measured, with the bonding/debonding procedures repeated once after the first debonding, and the bracket/adhesive failure modes were evaluated after each debonding. The treated bracket base surfaces were observed under a scanning electron microscopy (SEM). The mean rebond strengths were significantly lower in group 1 than in other groups, and there were no significant differences between the other groups. The mean initial bond strength was significantly higher than the mean rebond strength in group 1 but there was no significant difference between the two in the other three groups. Failures at the bracket-adhesive interface occurred frequently at second debonding in group 1. Under the SEM, residual adhesive was removed from the bracket bases by Er,Cr:YSGG laser, while adhesive remnant was seen underneath the meshwork of the bracket bases and microroughness appeared on the meshwork after sandblasting. Er,Cr:YSGG laser certainly could serve the purpose of promoting the use of recycled orthodontic brackets.