This study evaluated 60 children between 10 to 12 years presenting to a private orthodontic office in November and December 2018, seeking orthodontic treatment. G* power statistical power analysis program 3.1.1 was applied to determine sample size.19 A sample size of 50 was determined by considering a power of 0.85 and effect size of P = 0.23 for a two-tailed Spearman correlation test (p < 0.05). Sample size was increased to 60 to protect from possible dropping.
The selected patients met the following inclusion criteria:
(I) The treatment plan of patients included a removable orthodontic appliance with a midline screw along with a labial bow and Adams or Delta clasps on posterior teeth
(II) No history of orthodontic treatment
(III) Absence of maxillofacial syndromes such as cleft lip or palate, etc.
(IV) Absence of mental disorders
Four questioners were used in this study: Generalized Self-Efficacy Scale (GSES), Index of Orthodontic Treatment Need-Dental Health Component (IOTN-DHC) and Aesthetics Component (IOTN-AC), and compliance of orthodontic appliance questionnaire. Prior to the treatment onset, the patients filled out GSES and IOTN-AC; and IOTN-DHC were determined for each patient by researcher.
After delivery of the removable orthodontic appliance with a midline screw, labial bow, and Adams or Delta clasps on posterior teeth, the first follow-up session was scheduled at 1 month (T1). At the first follow-up, the patients filled out compliance questionnaire for the first time. The compliance questionnaire was filled out again by the patients 3 (T2), and 6 (T3) months after delivery. Written informed consent was obtained from the parents prior to the study. However, the questionnaires were filled out by patients in absence of parents. The researcher explained the questions in the questionnaires to the patients and instructed them on how to fill it out.
Study variables
1. IOTN:
The IOTN is an efficient tool for assessment of the need for orthodontic treatment in a community, and has several applications in programming, allocation of resources, and improvement of treatment standards. This index has two components: IOTN-DHC and IOTN-AC.20
In IOTN-DHC, the severity of malocclusion is divided into five grades. Higher grades indicate greater need for orthodontic treatment. Accordingly, the orthodontic treatment need can be divided into the following groups:
Group 1 (no need or slight need for orthodontic treatment): Grades 1 and 2
Group 2 (moderate need for orthodontic treatment): Grade 3
Group 3 (severe need for orthodontic treatment): Grade 4
Group 4 (very severe need for orthodontic treatment): Grade 5
The IOTN-AC is used to assess the patient satisfaction with the appearance of the teeth such that 10 images of different dentitions are shown to patients, and they are requested to pick the image with the highest resemblance to their dental status. Selection of images is interpreted as follows:
Images 1–4: Complete satisfaction or slight dissatisfaction with the appearance of the teeth
Images 5–7: Moderate satisfaction with the appearance of the teeth
Images 8–10: Complete dissatisfaction with the appearance of the teeth
2. GSES:
This questionnaire evaluates the confidence of individuals in their capabilities to succeed in different situations. It was first designed by SCHWARZER and JERUSALEM in 1995, and indicates the reliable correlation between the level of healthy behaviors and formation of health-related habits in an individual.16 This questionnaire has 10 items, which are scored according to a 4-point Likert scale. Each item has four answer choices, and the respondent should choose the statement that best describes his/her condition:
(I) Totally opposite to me (score 1)
(II) Slightly resembles me (score 2)
(III) Highly resembles me (score 3)
(IV) Perfectly resembles me (score 4)
This questionnaire is a single-component questionnaire and the scores of the items are summed. The total score can range from 10 to 40. Higher total scores indicate higher GSE of the individual. In this study, the Persian version of GSES was used. The validity and reliability of the Persian of this questionnaire have been previously confirmed.21
Compliance of orthodontic appliance questionnaire:
This questionnaire was used to assess the compliance of removable orthodontic appliance by patients. This questionnaire has 10 incomplete statements, which need to be completed by the patient’s choice. The available answer choices were scored using a 6-point Likert scale. In order to enhance the understanding of children from each answer choice, each answer choice had a matching facial expression over it (Table 1). Scores 5 to 0 were allocated to the answer choices from left to right. In other words, a higher score indicated higher compliance and satisfaction with the respective item. The total score of this questionnaire ranged from 0 to 55. A higher total score indicated that the patient better accepted the problems of using the removable orthodontic appliance and had higher motivation to continue the treatment.
Table 1
Compliance of orthodontic appliance scale.
Questions | Score 5 | Score 4 | Score 3 | Score 2 | Score 1 | Score 0 |
1.Speaking during using plaque | Doesn’t hurt at all | Hurts a bit | Hurts a little | Hurts | Hurts too much | Completely hurts |
| | | | | |
2.Swallowing saliva during using plaque. | Doesn’t hurt at all | Hurts a bit | Hurts a little | Hurts | Hurts too much | Completely hurts |
| | | | | |
3. Oral and dental appearance during using plaque | Doesn’t hurt at all | Hurts a bit | Hurts a little | Hurts | Hurts too much | Completely hurts |
| | | | | |
4. Facial appearance during using plaque | Doesn’t hurt at all | Hurts a bit | Hurts a little | Hurts | Hurts too much | Completely hurts |
| | | | | |
5. Oral hygiene during using plaque | Doesn’t hurt at all | Hurts a bit | Hurts a little | Hurts | Hurts too much | Completely hurts |
| | | | | |
6.Doing daily activities during using plaque | Doesn’t hurt at all | Hurts a bit | Hurts a little | Hurts | Hurts too much | Completely hurts |
| | | | | |
7. Sleeping during using plaque | Doesn’t hurt at all | Hurts a bit | Hurts a little | Hurts | Hurts too much | Completely hurts |
| | | | | |
8. Level of using plaque | Too much | much | often | few | little | Not all |
| | | | | |
9.Level of liking plaque | Too much | much | often | few | little | Not all |
| | | | | |
10. Level of liking to complete orthodontic treatment | Too much | much | often | few | little | Not all |
| | | | | |
Statistical analysis:
Data were analyzed using SPSS version 25 via descriptive and inferential statistics. In descriptive statistics, the frequency distribution of the IOTN-AC and IOTN-DHC scores was calculated for the participants. In inferential statistics, the reliability of the compliance questionnaire was evaluated using the Cronbach’s alpha test. According to the result of one-sample Kolmogorov-Smirnov test for normality assessment of variables, Friedman Two-way analysis of variance (ANOVA) and Wilcoxon signed rank test were applied to analyze the change in compliance questionnaire individual and total scores at T1, T2, and T3. The Spearman’s rho was calculated to assess the correlation between the mean total and individual scores (for the 10 items) of the compliance questionnaire filled out at T1, T2, T3 with the IOTN-DHC, IOTN-AC, and the GSES scores.