| Azeem and Hamid (2017)21 | journal of World Federation Orthodontist | CCT | 25 Randomized (12 Male, 13 Female) | Mean age, 16.17 ± 1.76 years | 1. Comprehensive clear aligner treatment of upper and lower arches2. Age 14-18 years at the start of aligner therapy3. No previous orthodontic therapy4. No hypodontia. | 1. Patients with any systemic disease, clefts, general dental problems, taking daily fluoride supplements or on ongoing medications for a chronic disease2. Patients with WSL, hypoplastic or fluorotic enamel | Not reported | Tooth groups used in the current studyGroup 1: n=4 (22-12) Maxillary incisors: 22, 21, 11, 12Group 2: n=20 (15-45) Maxillary and mandibular incisors, canines, first and second premolars: 11-15, 21-25, 31-35, 41-45Group 3: n=24 (16-46) Maxillary and mandibular incisors, canines, first and second premolars, and first molars ** Definition by World Dental Federation numbering system | 1. The overall incidence of new WSLs2. Tooth related WSL formation in tooth groups All measurements were made before and at the end of the treatment. |
| Albhaisi et al. (2020)18 | American Journal of Orthodontics and Dento facial Orthopedics | RCT | 49Randomized (39 female, 10 male)Group 1 : n=l 9Group 2: n=23* In total, 42 of the 49 participants recruited completed the study | 21.25 ± 3 yearsGroup 1 : 21.2 years.Group 2: 21.3 years. | 1. Healthy patients of both sexes between the ages of 17-242. Classi malocclusion with mild-to-moderate crowding (≤5 mm)3. Nonextraction treatment plan4. Optimum oral hygien | 1 .Patients with poor oral hygiene, defective enamel, extensive restorations, and salivary glands diseases | Orthodontic clinic at Jordan University of Science and Technology | The patients were divided into two groups by drawing lots.Group 1 : Treated with clear alignerGroup 2: Fixed orthodontic treatment*Quantitative light-induced fluorescence (QLF) images were taken before treatment (TO) and 3 months later (Tl). The QLF images were then analyzed to assess the research outcomes. | 1. Plaque measurements2. Changes in white spot lesion parameters3. Preexisting white spot lesions vs newly developed ones All measures before treatment and3 months after the start of treatment |
| Buschang et al. (2019)14 | Angle Orthodontist | CCT | 450RandomizedGroup 1: n=244Group 2: n=206*Gender not reported | Group 1: 30.4 years.Group 2: 29.2 years | 1. Patients in late mixed or permanent dentition with only high-quality digital photographs of pre- and post-treatment2. All malocclusion, provided that the gingival one-third of the anterior teeth is visible in the photographs | Not reported | Private practice and at the Department of Orthodontics, Texas A&M University College of Dentistry | Patients were chosen consecutively, starting with the most recently completed cases.Group 1: Treated with clear alignerGroup 2: Fixed orthodontic treatment Initial and final intraoral photographs were retrieved from the Dolphin Imaging System, placed side by side on a computer monitor, enlarged, and evaluated in a darkened room. | 1. Oral Hygiene Status2. The incidence of WSLs All measurements were made before and at the end of the treatment. |
| Alshatti (2017)19 | Master of Dental Science at the University of Connecticut, 2017 | RCT | 59RandomizedGroup 1 : n=24Group 2: n=l 6Group 3: n=l 9*Gender not reported | Group 1 : 21.44 yearsGroup 2: 1 4.83 yearsGroup 3: 1 4.47 years | 1 .Nonextraction treatment plan.2. There should be less than 8mm of anterior crowding.3. Patients should have all permanent teeth present, except third molars.4. Demonstrable ability to maintain adequate ora hygiene.5. Show optimum denta health without immediate need for restorations. | 1 .Skeletal anterior posterior discrepancies between the maxilla and mandible (ANB > 5°).2. Centric relation (CR)- Centric occlusion (CO) discrepancies of greater than 3 mm.3. Anterior or posterior open bites.4. Patients who are pregnant, diabetic or using mouth rinses or interacting medications, including antibiotic therapy. 5. Presence of impacted teeth.6. Presence of pre-treatment white spot lesions.7. Presence of active periodontal disease as evidenced by attachment loss. | Division of Orthodontics, Department of Craniofacia Sciences, University of Connecticut Health Center. | Randomization sequence was generated by using a PC based software “Random Allocation Software”.Group 1 : Patients receiving treatment with clear semi-elastic polyurethane aligners.Group 2: Patients receiving treatment with self-ligating brackets.Group 3: Patients receiving treatment with conventional pre-adjusted edge wise brackets. | 1 : Measuring the incidence of WSLs2. Measuring the severity (surface area) of wsls3. Measuring the correlation between gingival, plaque and bleeding ndices and white spot lesionsAll measurements were pre-treatment and (TO) 1 8 months after treatment initiation. (T2) done |
| Tuncay et al. (2013)20 | Journal of Clinical Orthodontist | RCT | 62Randomized*Gender not reported | Participants were under 18 years old | 1.Patients with class I or mild class II occlusion | 1. Active caries2. Periodontal disease3. Patients unsuitable for aligner | Michigan, New Jersey, Oklahoma, and Pennsylvania | 62 patients were treated by clinicians.It was recommended to use at least 21 hours a day.Of the 62 patients who began the study, 42 completed treatment. | 1. Gingival-index measurements2. Decalcification index3. Patient Satisfaction All measurements were collected in the first 24 months |
