Methods: PubMed, SCOPUS, Science Direct, Web of Science, and Google Scholar electronic databases were searched systematically with restricting the languages to only English and year (January 2001 to March 2020), and studies were selected based on the inclusion criteria. Study quality and publication bias were assessed by using the Robvis, a software package of R statistical software.

Results: This systematic review included 32 studies (1172 patients) based on the inclusion and exclusion criteria. Most of the studies reported significant reduction of pain by the use of the laser during TMD treatment. Two-thirds of the study (78.13%) found a better outcome comparing with conventional one. According to Robvis, 84.4% of the studies were high methodological studies with low risk of bias.

Materials and Methods: The study was performed using cell viability assay for mitochondrial dehydrogenase activity in stem cells from human exfoliated deciduous teeth (SHED), after 1, 2, and 3 days of exposure to the biomaterial extracts of varying concentrations. Differences in mean cell viability values were assessed by one-way analysis of variance, followed by Dunnett T3 post hoc test for multiple comparisons (P < 0.05).

Results: The cell viability to Gyp-CHT in low extract concentrations was statistically similar to that of the control and different from that of high extract concentrations. Gyp-5% CHT showed the highest percentage of cell viability with 110.92%, 108.56%, and 109.11%. The cell viability showed a tendency toward increment with low extract concentration and no constant effect of CHT on cell viability toward higher or lower.

PURPOSE: The purpose of this in vitro study was to evaluate the SR, tensile strength (TS), and percentage elongation (% E) of different SEs subjected to outdoor weathering in the Malaysian climate.

MATERIAL AND METHODS: Type-II dumbbell-shaped specimens (N-120) (nonweathered=15, weathered=15) were made from 3 room-temperature vulcanized (A-2000, A-2006, and A-103) and 1 heat-temperature vulcanized (M-511) silicone (Factor II). For 6 months, weathered specimens were subjected to outdoor weathering inside a custom exposure rack. Simultaneously, the nonweathered specimens were kept in a dehumidifier. Subsequently, the SR was measured with a profilometer; TS and % E were measured by using a universal testing machine. Two-way ANOVA was used to compare the means of the tested properties of the nonweathered and weathered specimens, and pairwise comparison was carried out between the silicones (α=.05).

RESULTS: After outdoor weathering, the SR, TS, and % E were adversely affected by weathering in the Malaysian environment. Among the silicone materials, A-2000 showed the least TS changes (2.51 MPa), while A-2006 demonstrated significant changes in percentage elongation after outdoor weathering (266.5%). M-511 exhibited the highest mean value (2.50 μm) for SR changes. In addition, A-103 SE showed statistically significant differences in most pairwise comparisons for all 3 dependent variables.

METHODS: Relevant articles written in English only, before January 15, 2017, were identified using an electronic search in the PubMed, Scopus, and Google Scholar databases. Furthermore, a manual search of the related major journals was also conducted to identify more pertinent articles. The relevancy of the articles was verified by screening the title, abstract, and full text if they met the inclusion criteria. A total of 37 articles satisfied the criteria, from which data were extracted for qualitative synthesis.

RESULTS: Among the 37 included articles, 14 were without aging, 15 were natural or artificial accelerated aging, 7 were outdoor weathering, and 1 contained both artificial aging and outdoor weathering. Only 4 studies out of the 14 without aging had significant observations; whereas 9 articles with natural or artificial aging published significant results, and 3 out of 7 outdoor weathering articles showed significant changes in the evaluated silicone elastomers.

Methods: Twenty-two patients (11 males and 11 females; mean age 19.18 ± 2.00 years) having Angle's Class II division 1 malocclusion needing bilateral extractions of maxillary first bicuspids were recruited for this split-mouth randomized clinical trial. After the initial stage of alignment and leveling with contemporary edgewise MBT (McLaughlin-Bennett-Trevisi) prescription brackets (Ortho Organizers, Carlsbad, Calif) of 22 mil, followed by extractions of premolars bilaterally, 6 mm nickel-titanium spring was used to retract the canines separately by applying 150 g force on 0.019 × 0.025-in stainless steel working archwires. LIPUS (1.1 MHz frequency and 30 mW/cm2 intensity output) was applied for 20 minutes extraorally and reapplied after 3 weeks for 2 more successive visits over the root of maxillary canine on the experimental side whereas the other side was placebo. A numerical rating scale- (NRS-) based questionnaire was given to the patients on each visit to record their weekly pain experience. Impressions were also made at each visit before the application of LIPUS (T1, T2, and T3). Models were scanned with a CAD/CAM scanner (Planmeca, Helsinki, Finland). Mann-Whitney U test was applied for comparison of canine movement and pain intensity between both the groups.

Results: No significant difference in the rate of canine movement was found among the experimental (0.90 mm ± 0.33 mm) and placebo groups (0.81 mm ± 0.32 mm). There was no difference in pain reduction between experimental and placebo groups (p > 0.05).

Materials and Methods: Twenty patients with Angle's class II div 1 (10 males and 10 females; aged 20.25 ± 3.88 years) needing bilateral extractions of maxillary first bicuspids were recruited. Conventional brackets MBT of 0.022 in slot (McLaughlin Bennett Trevisi) prescription braces (Ortho Organizers, Carlsbad, Calif) were bonded. After alignment and levelling phase, cuspid retraction began with nitinol closed coil spring on 19 × 25 stainless steel archwire, wielding 150 gram force. 7.5 J/cm2 energy was applied on 10 points (5 buccal and 5 palatal) on the canine roots on the investigational side using gallium-aluminum-arsenic diode laser (940 nm wavelength, iLase™ Biolase, Irvine, USA) in a continuous mode. Target tissues were irradiated once in three weeks for 9 weeks at a stretch (T0, T1, and T2). Patients were given a feedback form based on the numeric rating scale (NRS) to record the pain intensity for a week. Silicon impressions preceded the coil activation at each visit (T0, T1, T2, and T3), and the casts obtained were scanned with the Planmeca CAD/CAM™ (Helsinki, Finland) scanner.

Results: The regimen effectively accelerated (1.55 ± 0.25 mm) tooth movement with a significant reduction in distress on the investigational side as compared to the placebo side (94 ± 0.25 mm) (p < 0.05).

METHODS: Twenty-two patients (11 male, 11 female; mean age, 19.8 ± 3.1 years) with Angle Class II Division 1 malocclusion were recruited for this split-mouth clinical trial; they required extraction of maxillary first premolars bilaterally. After leveling and alignment with self-ligating brackets (SmartClip SL3; 3M Unitek, St Paul, Minn), a 150-g force was applied to retract the canines bilaterally using 6-mm nickel-titanium closed-coil springs on 0.019 x 0.025-in stainless steel archwires. A gallium-aluminum-arsenic diode laser (iLas; Biolase, Irvine, Calif) with a wavelength of 940 nm in a continuous mode (energy density, 7.5 J/cm2/point; diameter of optical fiber tip, 0.04 cm2) was applied at 5 points buccally and palatally around the canine roots on the experimental side; the other side was designated as the placebo. Laser irradiation was applied at baseline and then repeated after 3 weeks for 2 more consecutive follow-up visits. Questionnaires based on the numeric rating scale were given to the patients to record their pain intensity for 1 week. Impressions were made at each visit before the application of irradiation at baseline and the 3 visits. Models were scanned with a CAD/CAM scanner (Planmeca, Helsinki, Finland).

RESULTS: Canine retraction was significantly greater (1.60 ± 0.38 mm) on the experimental side compared with the placebo side (0.79 ± 0.35 mm) (P <0.05). Pain was significantly less on the experimental side only on the first day after application of LLLI and at the second visit (1.4 ± 0.82 and 1.4 ± 0.64) compared with the placebo sides (2.2 ± 0.41 and 2.4 ± 1.53).

Methods: A total of eighteen (18) malocclusion patients were identified. Malocclusion patients were subdivided into 3 groups based on the bracket selection (conventional, self-ligating, and ceramic bracket) with 6 patients for each group. sEMG of muscles were done using a two-channel electromyography device, where pregelled and self-adhesive electrodes (bilateral) were applied. Chewing and clenching of masseter and temporalis muscle activity were recorded for 20 s pre and 6 months of orthodontic treatment using sEMG (frequency 60 Hz). The data were analysed by using repeated measures ANOVA in IBM SPSS Statistics Version 24.0.

Results: Chewing and clenching for masseter muscle showed no significant difference (P > 0.05) in sEMG activity of three types of the brackets. However, for temporalis muscle, there was a significant difference found in sEMG activity during chewing (P < 0.05) and clenching (P < 0.05) between these three brackets.