Comparative assessment of treatment efficacy and adverse effects during nonextraction orthodontic treatment of Class I malocclusion patients with direct and indirect bonding: A parallel randomized clinical trial

Introduction

The objective of this 2-arm parallel trial was to compare the effects of direct and indirect bonding techniques on the orthodontic treatment process and outcomes.

Methods

Thirty patients were randomly assigned to undergo bonding of brackets indirectly (group A, n = 15) or directly (group B, n = 15). Eligibility criteria included permanent dentition with bilateral Angle Class I molar and canine relationships, no previous orthodontic treatment, no skeletal discrepancy, and mild or moderate crowding. The main outcome was the orthodontic treatment results assessed using the American Board of Orthodontics Objective Grading System; the secondary outcomes were times taken to perform the laboratory and clinical steps, total treatment duration, plaque accumulation, formation of white spot lesions, bond failures, and need for additional archwire bending and bracket repositioning. The randomization sequence was created using an online randomization software. The patients were allocated with a 1:1 ratio using a block size of 4. The sequence generator was contacted by phone for group assignment after a patient was enrolled for allocation concealment. Blinding was implemented during the dental cast and radiographic evaluations, data entry, and data analysis. Patients were evaluated before treatment, and 1, 2, and 6 months after the start of treatment, and at the end of treatment.

Results

All patients completed the study and were analyzed. There were no dropouts. Marginal ridge (median difference, −1.000; 95% confidence interval [CI], −2.99 to −0.001; P = 0.03) and total Objective Grading System scores (median difference, −3.999; 95% CI, −6.000 to −0.005; P = 0.03) were significantly higher in group B than in group A; other Objective Grading System categories did not differ significantly between the groups. The clinical time was significantly longer in group B than in group A (mean difference, −26.51; 95% CI, −29.57 to −23.46; P <0.001), and the total time was significantly longer in group A than in group B (mean difference, 19.03; 95% CI, 15.32 to 22.74; P <0.001). There were no significant between-group differences in treatment duration, plaque accumulation, formation of white spot lesions, bond failure, or need for additional archwire bending or bracket repositioning. No harms were encountered.

Conclusions

Indirect bonding was significantly faster than direct bonding in the clinical stage and yielded better marginal ridge and total scores. Both techniques showed similar rates of plaque accumulation, formation of white spot lesions, bond failure, and additional archwire bending and bracket repositioning.

Registration

The trial was not registered.

Protocol

The protocol was not published before trial commencement.

Highlights

  • Successful treatment outcomes were achieved with both bonding techniques.

  • Treatment duration, plaque accumulation, white spot lesions formation, and bond failure did not differ between groups.

  • Needs for additional bends and bracket repositioning did not differ between groups.

  • Marginal ridge and total OGS scores were better in the indirect group.

Direct bonding is the method most commonly used for attaching orthodontic appliances to teeth in clinical practice. However, use of indirect bonding has increased in recent years. The indirect bonding technique is a 2-stage procedure that was introduced by Silverman et al in 1972. The laboratory stage involves positioning and attachment of brackets on dental plaster models and preparation of transfer trays. These brackets are then transferred and bonded to the patient’s teeth in the clinical stage. Increased accuracy in bracket positioning and reduced clinical chair time have been suggested as the most important advantages of this technique.

Over the years, several in-vitro and in-vivo studies have compared direct and indirect bonding techniques with respect to bond strength, bond failure, accuracy of bracket placement, accumulation of plaque, formation of white spot lesions, treatment time, and time taken to complete the laboratory and clinical steps. In general, these studies have shown no differences between the 2 methods in terms of bond strength, bracket failure rate, treatment time, or effect on periodontal tissues.

Although accuracy in bracket positioning is an important reason that clinicians choose indirect over direct bonding, laboratory and clinical studies comparing these techniques have yielded contradictory results. Although some investigators have found only small differences in bracket placement errors between the 2 methods, others have shown that indirect bonding significantly reduces absolute torque error and rotation deviation, which can make it easier for the orthodontist to correct transverse discrepancy, disclusion with antagonist teeth, and irregularities in interproximal contact points. However, whether these differences would result in better overall orthodontic treatment outcomes is not clear.

Knowledge of the clinical variables that are affected by these different bonding techniques during orthodontic treatment might help clinicians when choosing the best method for bracket bonding.

Specific objectives or hypotheses

The aims of this study were to evaluate the effects of direct and indirect bonding techniques on the orthodontic treatment process and to compare the orthodontic treatment outcomes achieved using these 2 bonding methods. Our hypotheses were the following: (1) orthodontic treatment outcomes do not differ in patients treated using direct bonding and indirect bonding techniques; (2) there is no difference between the 2 bonding methods in terms of total treatment time, accumulation of plaque, formation of white spot lesions, bond failure rates, need for additional archwire bending and bracket repositioning; and (3) the chair-side time needed for indirect bonding of brackets is shorter than the time needed for direct bonding.

Material and methods

Trial design and any changes after trial commencement

This was a single-center, 2-arm parallel randomized clinical trial with a 1:1 allocation ratio. No changes were made to the protocol after trial commencement.

Participants, eligibility criteria, and settings

Initially, 47 patients who had been referred to a tertiary clinic in Ankara, Turkey for orthodontic treatment between January and June 2015 were assessed for eligibility by the senior clinician (B.S.A.). The inclusion criteria were as follows: (1) complete permanent dentition, including second molars with bilateral Angle Class I molar and canine relationships; (2) no previous orthodontic treatment; (3) no skeletal discrepancy; and (4) mild or moderate crowding. The exclusion criteria were (1) morphologic or numeric dental anomalies or enamel defects, (2) severe crowding or bimaxillary protrusion that would require tooth extraction, (3) cigarette smoking, (4) chronic use of medication, (5) systemic disease potentially affecting the study outcome, and (6) poor oral hygiene. The study was carried out in accordance with the tenets of the Declaration of Helsinki, and its protocol was approved by the scientific ethical committee at Hacettepe University, Ankara, Turkey (approval number 07-15/KA-15041). Informed consent was obtained from all patients or a parent.

Interventions

The patients were randomly allocated to 1 of 2 treatment groups: indirect bonding and (2) direct bonding. In the direct bonding group, the teeth were etched with 37% phosphoric acid gel (blue etchant gel with benzalkonium chloride; Reliance Orthodontic Products, Itasca, Ill) for 30 seconds, rinsed, dried with oil-free compressed air for 10 seconds. After drying the enamel surface, the primer (Transbond MIP Moisture Insensitive Primer; 3M Unitek, St Paul, Minn) was applied with a small brush and spread with oil-free compressed air. The brackets were then bonded using Transbond Plus Color Change Adhesive (3M Unitek) and polymerized for 40 seconds per bracket with a light-emitting diode curing light (Starlight S; Mectron, Carasco, Italy) ( Fig 1 ).

Fig 1
Direct bonding group: A, tooth preparation; B, placement of brackets; C, removal of excessive composite flash; and D, intraoral frontal view after direct bonding.

In the indirect bonding group, maxillary and mandibular arch impressions were taken with heavy-bodied alginate (Alginoplast MIP; Heraeus Kulzer, Hanau, Germany), and dental models were cast with hard dental stone. After the dental models dried, vertical and horizontal bracket-positioning guidelines were drawn. A separating agent (Isodent Gypsum Separating Fluid; SpofaDental, Bioggio, Switzerland) was applied on the tooth surfaces with a brush, and the casts were allowed to dry. The composite (Transbond Plus Color Change Adhesive) was applied to the bracket base, and the bracket was positioned on the tooth surface. The slot of the bracket was aligned to the horizontal guideline, and its long axis was aligned to the vertical guideline. After positioning of the bracket, the composite was polymerized, and a 2-layer transfer tray was prepared using translucent soft silicone (Memosil 2; Heraeus Kulzer), and thermoformed rigid Essix plastic (Raintree Essix, New Orleans, La). After cleaning the separating agent with a sandblasting machine, the tooth surfaces were prepared with the same method used in the direct bonding group. A low-viscosity composite (Transbond Supreme LV Low Viscosity Light Cure Adhesive; 3M Unitek) was applied to the gingival half of the bracket bases, and the transfer tray was then seated on the arch. The composite was polymerized for 20 seconds. After removal of the outer layer of the tray, each bracket was light-cured again for 20 seconds. The inner layer of the tray was removed, and excessive composite flash was removed using a tungsten carbide bur in an air rotor ( Fig 2 ).

Fig 2
Indirect bonding group: A, positioning of the brackets on dental casts according to positioning guidelines; B, 2-layer transfer tray; C, polymerization of the composite through the transfer tray; and D, intraoral frontal view after indirect bonding.

The patients were treated by the same orthodontic resident (K.Y.) under the supervision of the same faculty member who was also the thesis advisor (B.S.A.). The same fixed appliance was used in both groups (0.018-in slot stainless steel Roth prescription Empower 2 self-ligating brackets and 0.018-in Non Convertible LP direct bond molar tubes, American Orthodontics, Sheboygan, Wis). Both arches and all teeth, including the second molars, were bonded at the same appointment. The patients were treated with the same protocol with the following wire sequence: nickel titanium, 0.012, 0.014, 0.016, 0.016 × 0.016, and 0.016 × 0.022 in (Superelastic Nickel Titanium Memory Archwire, American Orthodontics), and stainless steel, 0.016 × 0.022 in (American Orthodontics). Interproximal reduction was used to eliminate crowding. The patients were seen every 4 weeks, and the next archwire was placed if the previous archwire had become passive. No auxilliary appliances were used during treatment. Additional archwire bends were used to detail the occlusion when needed. Intermaxillary elastics were given at the end of treatment for final posterior settling. The fixed appliances were debonded when Class I canine and molar relationships, ideal overjet and overbite, and a mutually protected functional occlusion were achieved. An anterior mandibular fixed retainer was bonded, and maxillary and mandibular clear overlay retainers were delivered.

Outcomes (primary and secondary) and any changes after trial commencement

The primary outcome measure of this study was the orthodontic treatment results assessed using the Objective Grading System (OGS) of the American Board of Orthodontics (ABO). The secondary outcome measures were times taken to perform the laboratory and clinical steps, total treatment duration, plaque accumulation (measured with the plaque index), formation of white spot lesions (measured with the white spot lesion index), bond failures, and need for additional archwire bending and bracket repositioning. All outcome measures were planned before the trial, and no changes were made after trial commencement.

Data were collected from January 2015 to October 2016. Extraoral and intraoral photographs, dental casts, and panoramic and lateral cephalometric radiographs were obtained before treatment and at the end of treatment. The OGS was used to evaluate treatment outcomes. All data were evaluated by the same investigator (K.Y.) as part of a thesis research project. The investigator was calibrated to the OGS using the ABO’s calibration kit and had been using the system for 3 years at the time of data evaluation.

To evaluate accumulation of plaque around the brackets, the plaque index introduced by Attin was measured before treatment (T0), 1 month after bonding (T1), 2 months after bonding (T2), 6 months after bonding (T3), and at the end of treatment (T4).

The white spot lesions index, introduced by Gorelick et al was measured at T0 and T4. The labial surfaces of all bonded teeth were evaluated visually in the clinic and on intraoral digital photographs.

Bond failures were recorded at each appointment, and the total number of bond failures was calculated between T0 and T4. The need for additional archwire bending and bracket repositioning at every appointment was noted.

The clinical time required for each bonding technique and the laboratory time required for indirect bonding were recorded, and the total time was calculated.

Sample size calculation

Since no previous studies had used the OGS to compare the results of orthodontic treatment in patients bonded with indirect and direct techniques, an a priori sample size calculation was carried out according to the results of a previous retrospective study. The calculation was based on the number of subjects required for an independent-sample t test. The sample size analysis was calculated using G*Power (version 3.1.9.2; Franz Faul, Universitat Kiel, Kiel, Germany) statistical software based on a previous retrospective study assessing the clinical outcomes of Roth (n = 20; ABO total score, 23.85 ± 2.70) and MBT (n = 20; ABO total score, 21.20 ± 2.37) prescription brackets; it indicated that a sample size of 15 subjects per group (n = 30) would be required for 80% power at P = 0.05 with a standard deviation of 2.5 in both groups.

Interim analysis and stopping guidelines

Not applicable.

Randomization (random number generation, allocation concealment, and implementation of the random sequence)

The randomization sequence was created by a statistician who was not taking part in the study using an online randomization software ( www.sealedenvelope.com ). The patients were allocated to treatment by block randomization in blocks of 4 with a 1:1 allocation ratio. To secure the allocation concealment, the sequence generator was contacted by phone for group assignment after a patient was enrolled.

Blinding

Neither the clinicians nor the patients were blinded to the intervention. The outcome assessor (K.Y.) was blinded during the dental cast and radiographic evaluations, data entry, and data analysis.

Statistical analysis

The statistical analysis was performed using SPSS Statistics for Windows software (version 22.0; IBM, Armonk, NY). A Shapiro-Wilk test was used to test the normality of the data. Either the Friedman test or the Wilcoxon signed rank test was used to determine differences in the same group. If significant differences were found with the Friedman test, the effects of time points on variables within groups were examined using the post hoc Dunn all pairwise test. Intergroup differences were analyzed using independent-samples t tests or Mann-Whitney U tests. Medians of differences and confidence intervals for variables with a nonnormal distribution were computed using R version 3.4.0, Boot Package (R Foundation for Statistical Computing, Vienna, Austria). The Bonferroni correction was used to adjust the P values for multiple testing. Statistical significance was set at P <0.05.

Error of the method

To ensure intraexaminer reliability, 10 subjects were randomly selected and remeasured by the same operator (K.Y.) 2 weeks after the first measurements. The records of 15 randomly selected subjects were also measured by a second operator (B.S.A.), an orthodontic specialist with 17 years of clinical experience to evaluate interexaminer reliability. Intraexaminer and interexaminer reliabilities were analyzed with Bland-Altman plots and intraclass correlation coefficients.

Material and methods

Trial design and any changes after trial commencement

This was a single-center, 2-arm parallel randomized clinical trial with a 1:1 allocation ratio. No changes were made to the protocol after trial commencement.

Participants, eligibility criteria, and settings

Initially, 47 patients who had been referred to a tertiary clinic in Ankara, Turkey for orthodontic treatment between January and June 2015 were assessed for eligibility by the senior clinician (B.S.A.). The inclusion criteria were as follows: (1) complete permanent dentition, including second molars with bilateral Angle Class I molar and canine relationships; (2) no previous orthodontic treatment; (3) no skeletal discrepancy; and (4) mild or moderate crowding. The exclusion criteria were (1) morphologic or numeric dental anomalies or enamel defects, (2) severe crowding or bimaxillary protrusion that would require tooth extraction, (3) cigarette smoking, (4) chronic use of medication, (5) systemic disease potentially affecting the study outcome, and (6) poor oral hygiene. The study was carried out in accordance with the tenets of the Declaration of Helsinki, and its protocol was approved by the scientific ethical committee at Hacettepe University, Ankara, Turkey (approval number 07-15/KA-15041). Informed consent was obtained from all patients or a parent.

Interventions

The patients were randomly allocated to 1 of 2 treatment groups: indirect bonding and (2) direct bonding. In the direct bonding group, the teeth were etched with 37% phosphoric acid gel (blue etchant gel with benzalkonium chloride; Reliance Orthodontic Products, Itasca, Ill) for 30 seconds, rinsed, dried with oil-free compressed air for 10 seconds. After drying the enamel surface, the primer (Transbond MIP Moisture Insensitive Primer; 3M Unitek, St Paul, Minn) was applied with a small brush and spread with oil-free compressed air. The brackets were then bonded using Transbond Plus Color Change Adhesive (3M Unitek) and polymerized for 40 seconds per bracket with a light-emitting diode curing light (Starlight S; Mectron, Carasco, Italy) ( Fig 1 ).

Fig 1
Direct bonding group: A, tooth preparation; B, placement of brackets; C, removal of excessive composite flash; and D, intraoral frontal view after direct bonding.

In the indirect bonding group, maxillary and mandibular arch impressions were taken with heavy-bodied alginate (Alginoplast MIP; Heraeus Kulzer, Hanau, Germany), and dental models were cast with hard dental stone. After the dental models dried, vertical and horizontal bracket-positioning guidelines were drawn. A separating agent (Isodent Gypsum Separating Fluid; SpofaDental, Bioggio, Switzerland) was applied on the tooth surfaces with a brush, and the casts were allowed to dry. The composite (Transbond Plus Color Change Adhesive) was applied to the bracket base, and the bracket was positioned on the tooth surface. The slot of the bracket was aligned to the horizontal guideline, and its long axis was aligned to the vertical guideline. After positioning of the bracket, the composite was polymerized, and a 2-layer transfer tray was prepared using translucent soft silicone (Memosil 2; Heraeus Kulzer), and thermoformed rigid Essix plastic (Raintree Essix, New Orleans, La). After cleaning the separating agent with a sandblasting machine, the tooth surfaces were prepared with the same method used in the direct bonding group. A low-viscosity composite (Transbond Supreme LV Low Viscosity Light Cure Adhesive; 3M Unitek) was applied to the gingival half of the bracket bases, and the transfer tray was then seated on the arch. The composite was polymerized for 20 seconds. After removal of the outer layer of the tray, each bracket was light-cured again for 20 seconds. The inner layer of the tray was removed, and excessive composite flash was removed using a tungsten carbide bur in an air rotor ( Fig 2 ).

Fig 2
Indirect bonding group: A, positioning of the brackets on dental casts according to positioning guidelines; B, 2-layer transfer tray; C, polymerization of the composite through the transfer tray; and D, intraoral frontal view after indirect bonding.

The patients were treated by the same orthodontic resident (K.Y.) under the supervision of the same faculty member who was also the thesis advisor (B.S.A.). The same fixed appliance was used in both groups (0.018-in slot stainless steel Roth prescription Empower 2 self-ligating brackets and 0.018-in Non Convertible LP direct bond molar tubes, American Orthodontics, Sheboygan, Wis). Both arches and all teeth, including the second molars, were bonded at the same appointment. The patients were treated with the same protocol with the following wire sequence: nickel titanium, 0.012, 0.014, 0.016, 0.016 × 0.016, and 0.016 × 0.022 in (Superelastic Nickel Titanium Memory Archwire, American Orthodontics), and stainless steel, 0.016 × 0.022 in (American Orthodontics). Interproximal reduction was used to eliminate crowding. The patients were seen every 4 weeks, and the next archwire was placed if the previous archwire had become passive. No auxilliary appliances were used during treatment. Additional archwire bends were used to detail the occlusion when needed. Intermaxillary elastics were given at the end of treatment for final posterior settling. The fixed appliances were debonded when Class I canine and molar relationships, ideal overjet and overbite, and a mutually protected functional occlusion were achieved. An anterior mandibular fixed retainer was bonded, and maxillary and mandibular clear overlay retainers were delivered.

Outcomes (primary and secondary) and any changes after trial commencement

The primary outcome measure of this study was the orthodontic treatment results assessed using the Objective Grading System (OGS) of the American Board of Orthodontics (ABO). The secondary outcome measures were times taken to perform the laboratory and clinical steps, total treatment duration, plaque accumulation (measured with the plaque index), formation of white spot lesions (measured with the white spot lesion index), bond failures, and need for additional archwire bending and bracket repositioning. All outcome measures were planned before the trial, and no changes were made after trial commencement.

Data were collected from January 2015 to October 2016. Extraoral and intraoral photographs, dental casts, and panoramic and lateral cephalometric radiographs were obtained before treatment and at the end of treatment. The OGS was used to evaluate treatment outcomes. All data were evaluated by the same investigator (K.Y.) as part of a thesis research project. The investigator was calibrated to the OGS using the ABO’s calibration kit and had been using the system for 3 years at the time of data evaluation.

To evaluate accumulation of plaque around the brackets, the plaque index introduced by Attin was measured before treatment (T0), 1 month after bonding (T1), 2 months after bonding (T2), 6 months after bonding (T3), and at the end of treatment (T4).

The white spot lesions index, introduced by Gorelick et al was measured at T0 and T4. The labial surfaces of all bonded teeth were evaluated visually in the clinic and on intraoral digital photographs.

Bond failures were recorded at each appointment, and the total number of bond failures was calculated between T0 and T4. The need for additional archwire bending and bracket repositioning at every appointment was noted.

The clinical time required for each bonding technique and the laboratory time required for indirect bonding were recorded, and the total time was calculated.

Sample size calculation

Since no previous studies had used the OGS to compare the results of orthodontic treatment in patients bonded with indirect and direct techniques, an a priori sample size calculation was carried out according to the results of a previous retrospective study. The calculation was based on the number of subjects required for an independent-sample t test. The sample size analysis was calculated using G*Power (version 3.1.9.2; Franz Faul, Universitat Kiel, Kiel, Germany) statistical software based on a previous retrospective study assessing the clinical outcomes of Roth (n = 20; ABO total score, 23.85 ± 2.70) and MBT (n = 20; ABO total score, 21.20 ± 2.37) prescription brackets; it indicated that a sample size of 15 subjects per group (n = 30) would be required for 80% power at P = 0.05 with a standard deviation of 2.5 in both groups.

Interim analysis and stopping guidelines

Not applicable.

Randomization (random number generation, allocation concealment, and implementation of the random sequence)

The randomization sequence was created by a statistician who was not taking part in the study using an online randomization software ( www.sealedenvelope.com ). The patients were allocated to treatment by block randomization in blocks of 4 with a 1:1 allocation ratio. To secure the allocation concealment, the sequence generator was contacted by phone for group assignment after a patient was enrolled.

Blinding

Neither the clinicians nor the patients were blinded to the intervention. The outcome assessor (K.Y.) was blinded during the dental cast and radiographic evaluations, data entry, and data analysis.

Statistical analysis

The statistical analysis was performed using SPSS Statistics for Windows software (version 22.0; IBM, Armonk, NY). A Shapiro-Wilk test was used to test the normality of the data. Either the Friedman test or the Wilcoxon signed rank test was used to determine differences in the same group. If significant differences were found with the Friedman test, the effects of time points on variables within groups were examined using the post hoc Dunn all pairwise test. Intergroup differences were analyzed using independent-samples t tests or Mann-Whitney U tests. Medians of differences and confidence intervals for variables with a nonnormal distribution were computed using R version 3.4.0, Boot Package (R Foundation for Statistical Computing, Vienna, Austria). The Bonferroni correction was used to adjust the P values for multiple testing. Statistical significance was set at P <0.05.

Error of the method

To ensure intraexaminer reliability, 10 subjects were randomly selected and remeasured by the same operator (K.Y.) 2 weeks after the first measurements. The records of 15 randomly selected subjects were also measured by a second operator (B.S.A.), an orthodontic specialist with 17 years of clinical experience to evaluate interexaminer reliability. Intraexaminer and interexaminer reliabilities were analyzed with Bland-Altman plots and intraclass correlation coefficients.

Results

Participant flow

Of the 47 patients who had been assessed for eligibility, 17 were excluded for not meeting the inclusion criteria (n = 7) or refusing to participate in the study (n = 10). Finally, 30 patients (23 female, 7 male; ages, 11-30 years) were randomly assigned to either indirect bonding (group A, n = 15; 10 female, 5 male patients) or direct bonding (group B, n = 15; 13 female, 2 male patients). Since there were no dropouts during the trial, the analyses were carried out in all patients (CONSORT flow diagram, Fig 3 ).

Fig 3
CONSORT diagram of patient flow during the trial.

Baseline data

Patient demographic and clinical characteristics at baseline are shown in Table I . The mean (± standard deviation) pretreatment ages were 16.7 ± 5.1 years in group A and 14.6 ± 2.4 years in group B. According to the total discrepancy index scores, the pretreatment complexity was moderate in both groups.

Table I
Baseline characteristics and discrepancy index (DI) scores of indirect bonding (group A) and direct bonding (group B)
Variable Group A (n = 15) Group B (n = 15)
n (%)
Female 10 (67%) 13 (87%)
Male 5 (33%) 2 (13%)
Mean ± SD (minimum-maximum)
Age (y) 16.7 ± 5.1 (11.4-21) 14.6 ± 2.4 (11.7-19.2)
Total DI 9.7 ± 5.2 (3-20) 8.0 ± 4.9 (4-21)

Numbers analyzed for each outcome, estimation and precision, and subgroup analyses

The results of the OGS analysis showed that marginal ridge (median difference, −1.000; 95% CI, −2.999 to −0.001; P = 0.03) and total OGS scores (median difference, −3.999; 95% CI, −6.000 to −0.005; P = 0.03) were significantly higher in group B than in group A, but other OGS categories did not differ significantly between the groups. The medians of total OGS scores in group A and group B were 14.00 (IQR = 4.00) and 19.00 (IQR = 7.00), respectively ( Table II ).

Table II
Comparison of OGS scores
OGS categories Group A (indirect bonding) Group B (direct bonding) Intergroup comparison
Median Min Max IQR n Median Min Max IQR n MdD 95% CI Significance
Lower Upper
Alignment 3.00 1.00 7.00 3.00 15 3.00 1.00 8.00 4.00 15 −0.001 −1.999 1.000 0.49
Marginal ridges 2.00 0.00 5.00 3.00 15 4.00 1.00 9.00 4.00 15 −1.000 −2.999 −0.001 0.03
Buccolingual inclinations 4.00 0.00 5.00 3.00 15 4.00 0.00 6.00 2.00 15 −0.001 −1.999 1.000 0.52
Overjet 0.00 0.00 3.00 2.00 15 1.00 0.00 4.00 2.00 15 −0.999 −1.000 0.003 0.16
Occlusal contacts 1.00 0.00 2.00 1.00 15 1.00 0.00 4.00 3.00 15 −0.999 −1,999 0.005 0.08
Occlusal relationships 0.00 0.00 3.00 1.00 15 0.00 0.00 2.00 0.00 15 0.001 −0.003 0.001 0.32
Interproximal contacts 0.00 0.00 1.00 0.00 15 0.00 0.00 0.00 0.00 15 0.000 0.000 0.006 0.31
Root angulations 2.00 1.00 5.00 2.00 15 2.00 1.00 5.00 3.00 15 0.004 −1.000 0.999 0.53
Total OGS score 14.00 10.00 18.00 4.00 15 19.00 9.00 28.00 7.00 15 −3.999 −6.000 −0.005 0.03
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Dec 10, 2018 | Posted by in Orthodontics | Comments Off on Comparative assessment of treatment efficacy and adverse effects during nonextraction orthodontic treatment of Class I malocclusion patients with direct and indirect bonding: A parallel randomized clinical trial
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