Topical 10% Povidone-Iodine in Preventing White Spots

Photograph

6 maxillary anterior teeth (central incisors, lateral incisors, and canines) will be photographed with a clinical cam in a 10-degree tilted head position to reduce reflection without drying teeth. A new development of white spot lesion of the maxillary 4 anterior teeth using a photograph at a baseline (before the placement of fixed appliances). The images will be labeled with randomly assigned patient ID numbers and dates, and stored on a password-protected computer for later analysis. The orthodontic graduate students will be trained to label the photos, and then deliver them to the study coordinator. A trained and calibrated independent evaluator will assess whether there are new white spot lesions by comparing progress with the baseline photos taken before the placement of fixed appliances. The examiner will be blind to group assignments.

Gingival index

The gingival index will be evaluated at the baseline (before the placement of the fixed appliances, 6 months, and 12 months after the placement) Scoring gingival index will be performed before the patient performs any oral hygiene procedures at the time of the visit. A modification of the Löe-Silness Gingival Index (GI) will be used, scoring the mid-labial aspect of the gingiva of each anterior tooth on a scale from 0 (normal gingiva); 1 (Mild inflammation: slight change in color and slight edema but no bleeding on probing); 2 (Moderate inflammation: redness, edema, and glazing, bleeding on probing); to 3 (severe inflammation: marked redness and edema, ulceration with tendency to spontaneous bleeding). Orthodontic graduate students will receive training and complete a calibration exercise for scoring the GI.

International Caries Detection and Assessment System (ICDAS)

After the gingival index has been completed, patients will be asked to brush and floss their teeth, and any residual plaque can be removed with a micro brush. ICDAS will be evaluated at the baseline (before the placement of the fixed appliances, 6 months, and 12 months after the placement). Regarding the ICDAS, only the anterior teeth will be assessed clinically by the graduate orthodontic student. No magnification will be used. The graduate student examiners will be trained and calibrated to establish inter-rater reliability on a sample of 10 patients with and without ICDAS pre-cavitated lesions by a trained gold standard examiner . (Minimum acceptable ICC=.7) A review for examiners will be held for 1 year.

Visual analog scale (VAS)

After the first topical application in the clinic, the participant will complete a 100 mm VAS anchored with "not acceptable at all" to "completely acceptable." This assessment will be completed again at the three-month recall.

Safety measure (allergic reaction and adverse effect)

Participants will be recalled by the orthodontic graduate students using Zoom 24-48 hours after the first application and the participant's mouth will be examined for oral lesions using a structured paper checklist which will include the participant ID, date, and the name of the person completing the checklist. At the same appointment, the caregiver will be interviewed to complete a paper questionnaire on adverse effects. The orthodontic graduate students will interview the caregiver who is self-identified as the main adult responsible for the participants\' orthodontic care. Caregiver and participants will be given an emergency telephone number and asked to report significant abnormalities the participant experiences. The principal investigator will review and follow up. If the patient is having a severe medical emergency, they will be directed to contact their physician and/or go to the emergency room immediately.