Metal Brackets Research Articles

Shear bond strength of metallic brackets bonded to enamel pretreated with CPP-ACP: a systematic review and meta-analysis of in vitro studies

BackgroundDevelopment of white spot lesions (WSLs) is common among orthodontic patients. Several measures have been introduced to prevent and remineralize the lesions. Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) is used for both prevention and remineralization. The effect of its application before bonding is controversial. This systematic review was conducted to investigate the most up to date available literature regarding the effect of CPP-ACP enamel pre-treatment on shear bond strength (SBS) of metallic orthodontic brackets.MethodsA search was conducted in electronic databases (MEDLINE (via PubMed), Scopus, Cochrane Library, Web of Science and Google scholar (grey literature)) up to March 29th, 2023. The inclusion criteria included in vitro studies comparing the SBS of metal orthodontic brackets following pre-treatment of enamel using CPP-ACP versus control. The exclusion criteria included study types other than in vitro studies, studies conducted on non-human enamel, or studies using CPP-ACP in combination with another intervention. The included studies were analysed by two reviewers, independently. The risk of bias assessment was done using a modified risk of bias tool. A Meta-analysis was performed. I2 values and Q-test were used for assessment of heterogeneity. Results were displayed in forest plots with a random-effects model. Standardized mean difference, standard error (SE) and 95% confidence intervals were calculated for all studies.ResultsThe search resulted in 76 articles. After duplicate removal and assessment for eligibility, 15 studies were included in the review. High statistical heterogeneity was found among the included studies using I2 values and Q-Test (I2 = 95.147%; Q = 288.456; df = 14; P < 0.001). The overall effect of CPP-ACP pre-treatment on the SBS of metal orthodontic brackets was not significant (Mean difference = 1.163 MPa, SE = 0.757, 95% CI = -0.321, 2.648, p value = 0.125). The use of CPP-ACP for prevention of WSLs did not significantly affect the SBS of brackets (Standardized mean difference = 1.009, SE = 0.884, 95% CI = -0.723, 2.740, p value = 0.254). No significant change was found when CPP-ACP was used for remineralization of WSLs (Standardized mean difference = 1.501, SE = 1.087, 95% CI = -0.630, 3.632, p value = 0.167).ConclusionsWithin the limitations of the study, the evidence suggests that the use of CPP-ACP for either prevention or remineralization of WSLs before bonding does not affect the SBS of metal orthodontic brackets.

Shear bond strength of orthodontic metal brackets bonded to two different types of zirconium crowns: An in-vitro comparative study

Shear bond strength of orthodontic metal brackets bonded to two different types of zirconium crowns: An in-vitro comparative study

Effects of the conventional, soft start, and pulse delay modes produced by light-emitting diode device on metal brackets bond strength and enamel damage: An in vitro comparative study

This study aimed to compare the bond strength and enamel damage following debonding of metal brackets cured by different light-curing modes: conventional, soft start, and pulse delay modes. Sixty extracted upper premolars were randomly divided into three groups according to the used light-curing mode. Metal brackets were bonded with a light-emitting diode device employing different modes. Group 1: conventional mode (10s mesial+10 s distal); group 2: soft start mode (15s mesial+15s distal); group 3: pulse delay mode (3s mesial+3s distal, followed by 3min of no photoactivation, then 9s mesial+9s distal). Radiant exposure was the same in all study groups. Shear bond strengths of the brackets were tested with a universal testing machine. A stereomicroscope was used to determine the number and length of enamel microcracks. One-Way ANOVA and Kruskal-Wallis tests were used to detect significant differences in shear bond strength and microcracks number and length among groups. The soft start and pulse delay modes produced significantly greater shear bond strength than the conventional mode (19.46±4.90MPa; 20.47±4.97MPa; 12.14±3.79MPa, respectively, P<0.001). However, there was no significant difference between the soft start and pulse delay groups (P=0.768). The number and length of microcracks increased significantly after debonding in all study groups. The change in microcracks length was not different among study groups. The soft start and pulse delay modes produced greater bond strength than the conventional mode without predisposing enamel to higher risk of damage. Conservative methods for debonding are still required.

Influence of Different Mouth Rinsing Agents on Friction During Sliding Mechanics Between Orthodontic Metal Brackets and Stainless Steel Archwire: A Comparative In Vitro Study.

Aim and objectives The aim of this in-vitro study is to evaluate and compare the effect of various mouth rinsing agents on frictional resistance through sliding mechanics among orthodontic metal brackets and stainless steel (SS) archwire. Materials and methods Each group comprised 15 samples of maxillary first premolar pre-adjusted edgewise SS movable, un-bonded brackets (Koden Inc., United States) which were welded with a power arm, where 100 gof the load was suspended. Brackets were ligated with elastic modules (Koden Inc., United States) onto the perspex sheet along with 0.019" x 0.025" SS archwire (Classic Orthodontics, United States) and were suspended from the upper component of the Instron machine. The coefficient of friction was tested in dry conditions (control), artificial saliva (AS) (Wet Mouth, ICPA Health Product Ltd., India), 0.2% chlorhexidine gluconate (CHG) mouthwash (Hexidine, ICPA Health Product Ltd., India), 0.05% sodium fluoride (NaF) mouthwash (ACT Anti-Cavity Fluoride Mouthwash, Sanofi Company, United States), charcoal (CC) mouthwash (Hello Activated Charcoal Extra Freshening Mouthwash, Hello Products LLC, United States) and ozone-infused oil-pulling solution with coconut oil (O3) (O3Essentials, Health Ranger Store, United States). In order to calculate the coefficient of friction, 50 L was addedto the test sample while moving at a 5 mm/min crosshead speed. The groups were compared using the one-way analysis of variance (ANOVA), and Tukey's post hoc analysis was performed for multiple pairwise comparisons. Results The coefficient of friction with the highest mean values was observed with the control group (2.01), followed by AS (1.79), and the least with O3(1.15). Statistically significant differences were observed with almost all groups of mouth rinsing agents, but NaF is significant with CHG and CC. However, CHG did not have any significant difference from CC. Conclusions Lower coefficient of frictional values were observed with the ozone-infused oil-pulling solution with coconut oil during sliding mechanics between metal brackets and stainless steel archwire. Almost all the mouth rinsing agents showed a significantly different coefficient of friction value.

Clinical observations of metal brackets detachment using a Russian adhesive complex

People are increasingly paying attention to their smile and occlusion. That led to the emergence of new adhesive materials, including domestic ones. The purpose of this study is to define the indicators of detachment of brackets from three companies during clinical observation within one year after their fixation using the domestic set “Compofix (ortho)”. The study included 30 patients who had brackets fixed on both jaws on 24 teeth (from the first molar of one segment to the first molar of the opposite segment). The patients were divided into three groups: Group I included 10 patients who were fixed with brackets from Equilibrium (Dentaurum, Germany). Group II included patients who were fixed with G&amp;H Orthodontics brackets (G&amp;H Wire Company, USA). Group III included patients with Hangzhou brackets (JET Medical Equipment Co., Ltd China, China). Fixation in all groups was performed according to one adhesive protocol using the “Compofix (ortho)” orthodontic kit (Vladmiva, Russian Federation). The indicators were distributed as follows: Group I (12.5%) Group II (5.83%) Group III (28.75%). The study showed that G&amp;H Orthodontics brackets (G&amp;H Wire Company, USA) showed the best fixation to tooth enamel. Hangzhou brackets (China) showed the worst indicators of fixation to tooth enamel. The domestic complex “Compofix (ortho)” showed positive clinical indicators of fixation.

Impact of Orthodontic Appliances on Hiring Prospects in Saudi Arabia: A Cross-Sectional Study.

This study provides valuable insights into the cosmetic impact of orthodontic appliances on job-hiring prospects in Saudi Arabia. Both ceramic braces and clear aligners are considered cosmetic corrective devices compared to traditional metallic braces. This survey-based, cross-sectional study used two models, one male, and one female. Four standardized smiling frontal photographs were taken for each model: one without any appliance and three with different orthodontic appliances (i.e., metal braces, ceramic braces, and clear aligners). The photographs of each model were shown to potential employers, followed by three questions for each photo to assess the employers' views on the applicants' professionalism, communication skills, and the likelihood of being hired. The survey was distributed via an electronic questionnaire to employers in Saudi Arabia, collecting feedback from 189 participants. The sample was collected from October 2022 to February 2023. The models' scores while wearing metal and ceramic bracket appliances were significantly lower than when the models were wearing clear aligners or were not wearing any appliance in each domain. In conclusion, orthodontic appliances have cosmetic implications that affect job-hiring prospects, with a higher chance of being hired if the candidate does not have an orthodontic appliance.

Comparison of the shear bond strength of new and recycled metallic brackets using different adhesive materials : an in vitro study.

To evaluate and compare shear bond strength (SBS) of new and recycled metallic brackets bonded to conditioned and reconditioned enamel, using two different adhesive materials. 72 extracted sound human premolars were randomly divided into 6 groups. Transbond XT light cured composite (LCC) and Fuji Ortho LC resin-modified glass ionomer (RMGI), were used as adhesive materials. In groups 1 and 2 (control), new brackets were bonded to sound premolars using either LCC or RMGI, respectively. In Groups 3 and 4, new brackets were bonded to reconditioned enamel; and in groups 5 and 6, sandblasted recycled brackets were rebonded to reconditioned enamel. After 5.000 thermal cycles between 5ºC and 55ºC, SBS was evaluated and adhesive remnant on the enamel assessed using the ARI index. Statistical analyses included Shapiro-Wilk, ANOVA, Fligner-Killeen ANOVA and Tukey tests. The statistical analysis showed no significant difference in SBS comparing control and experimental groups for either new or recycled brackets (p = 0.848). The SBS was significantly higher in brackets bonded with LCC (15.7 MPa) than RMGI (11.6 MPa) (p = 0.006). Adhesive failure was the most frequent, with the adhesive remnant covering more than 50% of the bracket base. No significant differences were observed in SBS using either new or recycled brackets, regardless of the dental surface treatment (conditioned or reconditioned). Significantly higher SBS values were obtained with LCC adhesive. Adhesive failure prevails in all groups.

Intracranial pressure measurement under shock wave based on physical head surrogate

In order to explore the intracranial pressure response under different sensor fixation modes, the experimental study on the pressure measurement based on physical head surrogate under shock wave is carried out. The influence of different sensor fixation methods on the intracranial pressure was analyzed. The results show that sensor fixation mode has little influence on the pressure test results. The deviation between the pressure peak and impulse is only 3.62% and 4.54% in the two modes of hot melt supporting and free suspension. The deviation of pressure peak value between metal supporting and free suspension is 5.59%. In comparison, hot melt supporting fixation has less influence on intracranial pressure results. The orientation of sensor sensitive surface has little influence on the pressure test results. When sensor was fixed by the metal bracket, the deviation of pressure peak is only 4.03% between sensitive surface face to impact source and sensitive surface back to shock source.

P‐37: Design and research of thermal soaking scheme for COG display module

Glass direct current product USES the uA level, LED chip light‐emitting efficiency under different temperature differences. Because of the glass substrate, high thermal conductivity, glass and metal bracket assembled light board, due to the contact position and not contact position Z to thermal resistance difference is bigger, results in a larger temperature difference in the surface, lead to white picture, stimulation and phenomenon of tic‐tac‐toe grid. Analyze the lamp plate heat source, according to the thermal distribution of different location, by adopting insulation tape, multilayer graphite flake scheme improve lamp plate to the heat conduction ability, X/Y for COF package IC and light insulating board contact with the aluminum frame position, improve the mold inside lamp panel heat distribution. Test: by improving measures after the light in the same drive power module can be glass straight under in‐plane horizontal arrows temperature reduced from 2.5 ℃ to 1.4 ℃, the improved white showing effect.

Evaluation of Orthodontic Treatment Method Preferences of Dentistry Students, Dentists and Orthodontic Residents.

The aim of this study was to evaluate orthodontic treatment method preferences among dentistry students, dentists and orthodontic residents taking into account factors such as esthetics, advantage/disadvantage, cost and treatment duration. The study was carried out on three groups: dentistry students (n=318), dentists (n=110) and orthodontic residents (n=98), and a 17-question survey was applied. Questionnaire forms included informational photos of conventional metal brackets (CMB), esthetic ceramic brackets (ECB), self-ligating brackets (SLB), clear aligner (CA), and lingual brackets (LB). The participants' preferences for orthodontic treatment methods were evaluated using chi-square analysis, not only between groups but also considering gender and income level. Regarding esthetics, dentists (41%) and orthodontic residents (78%) mostly preferred CA, while dentistry students mostly preferred LB (44%). With regard to advantage/disadvantage, dentistry students (31%) and dentists (39%) mostly preferred SLB, while orthodontic residents mostly preferred CA (55%). Regarding the success of the treatment, all three groups mostly preferred CMB. (respectively 50%; 47%; 72%). While CA was mostly preferred for short-term treatments in all three groups (respectively 40%; 71%; 88%), CMB was mostly preferred for long-term treatments (respectively 35%, 51%, 55%). Gender and income-level differences had little effect on orthodontic treatment method preferences. Except for long-term treatments and treatment success, there was generally great interest in CA, especially among orthodontic residents. Ceramic brackets and LB were generally the least preferred treatment methods among dentistry students, dentists, and orthodontic residents.

Antioxidant effect on shear bond strength of orthodontic brackets after tooth bleaching: A scoping review of in vitro studies

Tooth bleaching was reported to decrease bond strength of orthodontic brackets. The antioxidant application was investigated to reverse the bleaching effect for immediate bracket bonding. This scoping review of in vitro studies is to assess systematically the effect of antioxidant application on shear bond strength (SBS) before orthodontic bracket bonding after tooth bleaching. This review was provided according to the Preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews (PRISMA-ScR) guidelines. An electronic literature search was performed for full-text articles in English via Scopus, Web of Science, MEDLINE/PubMed, and Google Scholar databases from 2012 to May 9, 2023. A total of 549 records were retrieved from the electronic search, and 361 after discarding duplicates. According to eligibility criteria, 23 records were included in this study. Included studies revealed that antioxidants could increase the SBS of brackets after bleaching. However, there was controversiality whether SBS was just improved or restored to the unbleached level according to various factors, including the antioxidant type, concentration, application time, and form. Most studies reported that 10% sodium ascorbate (SA), ascorbic acid, green tea (GT), and tocopherol solutions restored SBS of metal brackets but not ceramic brackets. The result of 10% SA and GT gel was controversial. Lower concentrations than 10% was effective with pink bark, grape seed, quercetin flavonoid, and chamomile to restore SBS. The included studies revealed that retinol acetate, gooseberry, and dimethyl sulfoxide did not restore SBS.

Effect of incorporating silica-hydroxyapatite-silver hybrid nanoparticles into the resin-modified glass ionomer on the adhesive remnant index score and shear bond strength of orthodontic metal brackets: An in vitro study

This study aimed to assess the effect of addition of silica-hydroxyapatite-silver (Si-HA-Ag) hybrid nanoparticles to light-cure glass ionomer (GI) on shear bond strength (SBS) of metal brackets bonded with this adhesive and the adhesive remnant index (ARI) score. In this in vitro experimental study, 50 sound extracted premolars were assigned to 5 groups (n=10) for orthodontic metal bracket bonding with BracePaste® composite, Fuji ORTHO™ pure resin modified GI (RMGI), and RMGI reinforced with 2wt%, 5wt% and 10wt% Si-HA-Ag nanoparticles. The SBS of brackets was measured by a universal testing machine. Debonded specimens were inspected under a stereomicroscope at×10 magnification to determine the ARI score. Data were analyzed by one-way ANOVA, Scheffe test, Chi-square test, and Fisher's exact test (alpha=0.05). The maximum mean SBS was recorded in BracePaste® composite followed by 2% RMGI, 0% RMGI, 5% RMGI and 10% RMGI. Only the difference between the BracePaste® composite and 10% RMGI was significant in this regard (P=0.006). The groups were not significantly different regarding the ARI scores (P=0.665). All the SBS values were within the clinically acceptable range. Addition of 2wt% and 5wt% Si-HA-Ag hybrid nanoparticles to RMGI as orthodontic adhesive caused no significant change in SBS of orthodontic metal brackets while addition of 10wt% hybrid nanoparticles significantly decreased the SBS. Nonetheless, all the SBS values were within the clinically acceptable range. Addition of hybrid nanoparticles had no significant effect on the ARI score.

Effect of orthodontic bonding with different surface treatments on color stability and translucency of full cubic stabilized zirconia after coffee thermocycling.

To assess the color stability and translucency of full cubic stabilized zirconia (FSZ) following orthodontic bonding with different surface treatments and coffee thermocycling (CTC). This in vitro study was conducted on 120 disc-shaped specimens of FSZ. Thirty specimens were selected as the control group and remained intact. The remaining specimens were randomly divided into three groups based on the type of surface treatment (n = 30): airborne particle abrasion (APA), silica-coating (CoJet), and carbon dioxide (CO2) laser. After metal bracket bonding in the test groups, debonding and polishing were performed. Subsequently, all specimens underwent CTC (10,000 cycles). Color parameters, color difference (ΔE00), and translucency parameter (TP) were measured three times at baseline (t0), after debonding and polishing (t1), and after CTC (t2). Data were statistically analyzed (α = 0.05). Significant difference existed among the groups regarding ΔE00t0t2 (p < 0.001). The APA group showed minimum (ΔE00 = 1.15 ± 0.53) and the control group showed maximum (ΔE00 = 0.19 ± 0.02) color stability, with no significant difference between the laser and CoJet groups (p = 0.511). The four groups were significantly different regarding ΔTPt0t2 (p < 0.001). Maximal increases in TP were noted in the CoJet (1.00 ± 0.18) and APA (1.04 ± 0.38) groups while minimal increase was recorded in the control group (0.1 ± 0.02). Orthodontic treatment makes zirconia restorations susceptible to discoloration and increased translucency. Nonetheless, the recorded ΔE00 and ΔTP did not exceed the acceptability threshold.

Assessment of enamel surface roughness and hardness with metal and ceramic orthodontic brackets using different etching and adhesive systems: An in vitro study

BackgroundThis study aimed to evaluate enamel surface roughness and microhardness following the use of different bracket materials (metal or ceramic), etchants (total- and self-etchants), and adhesive systems (precoated or flash-free). MethodA total of 99 extracted human premolars were selected for the analysis. The surface roughness was first assessed (roughness control). One specimen from each subgroup was examined using a scanning electron microscope to illustrate the surface topography. Eighty-eight teeth were prepared using total- or self-etchants and bonded to precoated or flash-free adhesive metal or ceramic brackets. The remaining 11 specimens were not bonded to brackets (microhardness controls). The brackets were debonded after immersion in distilled water for 24 h. The specimens were again scanned for surface roughness and topography imaging. Finally, the microhardness was assessed using a micro-Vickers hardness test at a force of 200 g for 10 s. ResultAn overall statistically significant increase in surface roughness and reduced surface microhardness were observed in all experimental groups when compared with those in the control groups. The etchant type was the only variable found to contribute to the measured surface properties, with increased roughness and reduced microhardness introduced by total-etching compared to those by self-etching. ConclusionOrthodontic brackets introduced a significant increase in enamel surface roughness and reduce microhardness compared with untreated enamel, regardless of the bracket material, etchant type, and adhesive system. The etchant type was the only variable contributing to these changes, with total etching having a more pronounced effect.

Influence of Individual Bracket Base Design on the Shear Bond Strength of In-Office 3D Printed Brackets-An In Vitro Study.

(1) Background: Novel high-performance polymers for medical 3D printing enable in-office manufacturing of fully customized brackets. Previous studies have investigated clinically relevant parameters such as manufacturing precision, torque transmission, and fracture stability. The aim of this study is to evaluate different design options of the bracket base concerning the adhesive bond between the bracket and tooth, measured as the shear bond strength (SBS) and maximum force (Fmax) according to DIN 13990. (2) Methods: Three different designs for printed bracket bases were compared with a conventional metal bracket (C). The following configurations were chosen for the base design: Matching of the base to the anatomy of the tooth surface, size of the cross-sectional area corresponding to the control group (C), and a micro- (A) and macro- (B) retentive design of the base surface. In addition, a group with a micro-retentive base (D) matched to the tooth surface and an increased size was studied. The groups were analyzed for SBS, Fmax, and adhesive remnant index (ARI). The Kruskal-Wallis test with a post hoc test (Dunn-Bonferroni) and Mann-Whitney U test were used for statistical analysis (significance level: p < 0.05). (3) Results: The values for SBS and Fmax were highest in C (SBS: 12.0 ± 3.8 MPa; Fmax: 115.7 ± 36.6 N). For the printed brackets, there were significant differences between A and B (A: SBS 8.8 ± 2.3 MPa, Fmax 84.7 ± 21.8 N; B: SBS 12.0 ± 2.1 MPa, Fmax 106.5 ± 20.7 N). Fmax was significantly different for A and D (D: Fmax 118.5 ± 22.8 N). The ARI score was highest for A and lowest for C. (4) Conclusions: This study shows that conventional brackets form a more stable bond with the tooth than the 3D-printed brackets. However, for successful clinical use, the shear bond strength of the printed brackets can be increased with a macro-retentive design and/or enlargement of the base.

(440) Quality of Life, Including Sexual Life of Orthodontic Appliance Users

Abstract Introduction Orthodontic treatment is closely related to the quality of life, including sexual life. Oral health obliges us to take a holistic approach to sexual health. Regarding the sexuality of orthodontic appliance users, no such studies have been conducted so far. Objective The main goal of the study was to analyze the quality of life, including sexual life of orthodontic appliance users. Methods 922 people over 18 years old who were undergoing orthodontic treatment with fixed appliances or aligners were selected for the study. Data for the study were obtained using two standardized questionnaires: The Satisfaction With Life Scale and The Sexual Satisfaction Questionnaire, a metric and an author’s questionnaire. Results The study group consisted of 922 people, including 718 women and 204 men, aged 20 to 56 years. All subjects were undergoing orthodontic treatment. Among the respondents, both men and women, the treatment process with the use of classic fixed appliances with metal brackets (n = 544) was dominating. Another group of orthodontic appliance users were patients with fixed appliances with aesthetic brackets (ceramic, porcelain, crystal) (n = 194). The patients treated with aligners were found only in the women's group (n = 145). The average orthodontic treatment time ranged from 1 to 1.5 years, however, there were individuals treated for more than 2 years. The mean score of satisfaction with life in the study group was 20.85. The study showed that men achieve statistically significantly higher results than women on the Satisfaction With Life Scale (p &amp;lt;0.00). The mean score of sexual satisfaction in the study group was 31.10. Regarding the selfassessment of sexual satisfaction, a statistically significant difference was noticed between women and men (p &amp;lt;0.001) – men assessed their sexual life higher than women. The relationship between sexual satisfaction and self-esteem in sexual life proved to be closely related. The self-esteem of the respondents was consistent with the results obtained in a standardized questionnaire and the high self-esteem rate was accompanied by high, objectively assessed sexual satisfaction scores. Sexual satisfaction was also strongly correlated with the respondents' attitude to the orthodontic appliances, the level of satisfaction with the relationship, and the frequency of sexual intercourse. The study demonstrated positive correlations of the sexual satisfaction score with the overall quality of life. Conclusions The attitude of the respondents to the orthodontic appliances has an impact on their quality of life, including sexual life. The orthodontic appliances may generate difficulties (the reduction of frequency or discontinuation) in subjects' sexual behavior, such as kissing and oral sex. Orthodontic appliances may also cause injury during sexual intercourse. The lack of reliable information on the relationship between orthodontic treatment and sexuality forces a need to raise awareness among dentists and orthodontic appliance users about the topics related to orthodontic treatment and sexual health. Disclosure No

Shear Bond Strength and Antibacterial Efficacy of Cinnamon and Titanium Dioxide Nanoparticles Incorporated Experimental Orthodontic Adhesive—An In Vitro Comparative Study

This in vitro study compared the shear bond strength (SBS) and antibacterial efficacy of an orthodontic adhesive containing either cinnamon or titanium dioxide (TiO2) nanoparticles (NPs). A total sample of 120 freshly extracted teeth was randomly divided into three groups, according to the type of NPs incorporated into adhesive for metallic orthodontic brackets’ bonding: group 1—conventional orthodontic adhesive (TXT) as a control; group 2—conventional orthodontic adhesive mixed with TiO2 NPs (TXT + TNP); and group 3—conventional orthodontic adhesive mixed with cinnamon NPs (TXT + CNP). The SBS and adhesive remnant index (ARI) scores were evaluated and compared between the groups. The antibacterial efficacy against Streptococcus mutans for all the groups was assessed via a disc agar diffusion test. Data comparisons among groups were performed by ANOVA followed by Bonferroni post hoc test. Antibacterial efficacy comparison between the experimental groups was performed via an independent t-test. The significance level for all the tests was set at p ≤ 0.05. The highest mean SBS values (10.11 ± 1.88 MPa) were in the TXT control group followed by TXT + TNP (9.40 ± 1.78 MPa), and the lowest SBS was in the TXT + CNP (8.99 ± 1.77 MPa) group. The mean SBS among the experimental groups was non-significant (p = 0.241). Antibacterial effects significantly increased (p ≤ 0.05) in both experimental groups. However, TXT + TNP revealed a significantly higher antibacterial effect (p = 0.021) than TXT + CNP. In conclusion, incorporating cinnamon or TiO2 NPs into an orthodontic adhesive improves its antibacterial effects without compromising the bond strength for clinical purposes.

Incorporation of Zirconium Oxide Nanoparticles in Adhesive Resin for Bonding of Brackets to Enamel Conditioned with Er,Cr:YSGG, Photodynamic Therapy, and Phosphoric Acid.

Objective: To evaluate the effect of enamel conditioning methods, that is, total-etch and rinse (TER), Er,Cr:YSGG (ECYL), and photodynamic therapy (PDT) on the shear bond strength (SBS) of orthodontic metallic brackets bonded using Zirconium oxide experimental adhesive (ZOEA). Methods: Sixty human incisor buccal surfaces were cleaned and allocated into three groups based on the method of enamel surface treatment, that is, TER using 37% phosphoric acid gel, methylene blue photosensitizer activated by PDT and ECYL (n = 20 each). Each group was further divided into two subgroups (n = 10) based on the type of adhesive, that is, ZOEA and experimental adhesive (EA). Metallic brackets were seated using composite resin. Samples were placed in a universal testing machine for SBS and failure mode using the ARI index. One-way analysis of variance and post hoc Tukey were used for multiple comparisons. ARI was presented in percentages in different investigated groups. Results: TER+ZOEA (17.16 ± 0.41 MPa) displayed the highest bond integrity. However, group PDT+EA (11.34 ± 0.25 MPa) demonstrated the lowest bond scores. The intergroup comparison revealed that the TER system displayed significantly higher SBS values than the PDT and ECYL groups (p < 0.05). The intragroup comparison revealed that enamel conditioned with TER and brackets bonded with ZOEA and EA displayed comparable bond integrity (p > 0.05). Conclusions: Enamel conditioned with TER bonded to a metallic bracket displayed better bond strength than PDT and ECYL. Zirconium oxide nanoparticles incorporated in adhesive have proved to be promising in improving the bond integrity of adhesive.

Shear bond strength of orthodontic brackets bonded to a new version of zirconium all ceramic restoration: An in vitro comparative study

ObjectivesEsthetic restorations such as monolithic zirconia crowns are highly requested for adults nowadays. Bonding orthodontic braces on this type of material became a challenge for orthodontists, because of the special surface treatment needed. This study aims to assess the shear bond strength (SBS) of metal, and ceramic brackets bonded on two types of zirconia ceramics, surface roughness (SR) after different surface treatments for their surfaces, and adhesive remnant index (ARI). Materials and methodsBrackets’ base surface area (BSA) was scanned by an extra-oral scanner, then measured. The doubled labial surface of monolithic zirconia crowns (n = 30) and monolithic high translucent zirconia crowns (n = 30) were prepared and each was divided into three groups (n = 10) depending on surface treatment (hydrofluoric acid etching, no treatment, and rocatec airborne abrasion). Extracted lower central incisors (n = 20) were prepared. Each of them was divided into two subgroups depending on the type of bracket bonded on their surfaces (metal and ceramic). The SR, SBS, and ARI were assessed. Statistical analysis usedTests used are independent-samples t-test, Fisher's exact test, One-Way ANOVA, and Kruskal-Wallis test. ResultsThe highest SBS and SR were observed in Enamel/Metal and Zirconia/Metal/Rocatec subgroups, respectively. ConclusionAdequate bond strength could be obtained with the high translucent zirconia group if bonded with ceramic or metal brackets even if no treatment was used. Clinical significanceA proportion of simulation was done like practicing inside the dental clinic to reach the best results regarding the adhesion strength of orthodontic brackets.

Quantitative Volumetric Enamel Loss after Orthodontic Debracketing/Debonding and Clean-Up Procedures: A Systematic Review

Objectives: To conduct a systematic review assessing quantitative enamel loss occurring after orthodontic debonding and clean-up procedures. Materials and Methods: A systematic search following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was performed on different databases (Embase, Medline, Scopus, Web of Science) for papers investigating volumetric enamel loss due to bracket and clear aligner attachment debonding and/or clean-up procedures. Studies investigating in vivo and in vitro articles published in the English language until 16 July 2022 were included. The study selection was then performed by two authors who screened the abstracts independently. Results: Of 421 screened abstracts, 41 articles were selected for full-text analysis. Finally, nine studies were included in this review. No in vivo papers were retrieved. In vitro papers investigated volumetric loss caused by the removal of metal brackets (n = 7), ceramic brackets (n = 1), and both (n = 1). The clean-up procedure varied among all investigations. Impressions at baseline and after debonding/clean-up were superimposed, and the volumes were subtracted using different 3D digital analysis software. Among all included studies, the volumetric loss of enamel ranged from 0.02 ± 0.01 mm3 to 0.61 ± 0.51 mm3 per tooth. Conclusions: Debonding and clean-up procedures produce enamel loss. The debonding/clean-up procedure that is able to cause the least enamel volume loss has yet to be identified.