Abstract : Objective: Lingual fixed retainers, made from 0.0175-inch 3-strand twisted stainless steel wire (TW) and 0.016 × 0.022-inch straight rectangular wire (RW), are generally used in clinical practice. This study aimed to calculate their accuracy by comparing the discrepancy between computer-aided customized retainers made from these two types of wires. Methods: Eleven orthodontic patients were selected, resulting in 22 maxillary and mandibular three-dimensional printing dental models. Two types of lingual fixed retainers were bonded from canine to canine. To determine the accuracy, five points were chosen for each model, resulting in 110 selected points. The absolute values of the distances on the x-, y-, and z-axes were measured to compare the accuracy of the two types of computer-aided retainers. Results: The accuracy of the two types of retainers did not differ significantly in the x- and z-axes, but only in the y-axis (P < 0.01), where RW-fixed retainers exhibited a slightly but significantly increased distance compared to the TW. Conclusions: Both types of retainers showed high accuracy; however, RW had a slight but statistically significant difference along the y-axis compared with TW. This type of computer-aided design/computer-aided manufacturing bending machine is limited to two dimensions, and the dental arch is curved. Therefore, RW may require slight manual adjustment by the practitioner after manufacturing.
Abstract : Objective: To assess the effectiveness of leukocyte–platelet-rich fibrin (L-PRF) compared with conventional treatment on canine retraction, rotation, pain, and soft tissue healing. Methods: Sixteen adult patients aged 18–25 years (10 females, and 6 males; mean age 22.25 ± 2.26 years) with Class I bimaxillary protrusion and Class II div 1 malocclusion participated in this single-center, split-mouth randomized controlled trial at the Orthodontics Department of a single hospital in SCB Dental College and Hospital, Cuttack, India. Randomization was performed using a computer-assisted function with a 1:1 allocation ratio. The intervention included the placement of L-PRF on the experimental side and follow-up for 90 days. The primary outcome measures were canine retraction, rotation, pain, and soft tissue healing. The range of tooth movement was evaluated at 15-day intervals: 0th day (T0), 15th day (T1), 30th day (T2), 45th day (T3), 60th day (T4), 75th day (T5), and 90th day (T6). Canine rotation was assessed at T0 and T6, and pain and soft tissue healing were evaluated on the 3rd, 7th, and 15th days of the treatment. Results: Cumulatively, the L-PRF group demonstrated a significantly greater tooth movement as compared to conventional treatment group (P < 0.001). Overall, canine retraction was 1.5 times greater on the L-PRF side than on the control side. Canine rotation showed no significant relationship, whereas pain and soft tissue healing were significantly better on the L-PRF side than on the control side. Conclusions: Local administration of L-PRF amplifies canine retraction while improving pain and soft tissue repair.
Abstract : Objective: To correlate temporomandibular joint (TMJ) morphology and position with cone-beam computed tomography (CBCT) images, Joint Vibration Analysis (JVA), and Jaw Tracker (JT) to develop a radiation-free, dynamic method for screening and monitoring the TMJ in orthodontic patients. Methods: A total of 236 orthodontic patients without symptoms of TMJ disorders who had undergone CBCT were selected for the JVA and JT tests in this cross-sectional study. TMJ position and morphology were measured using a three-dimensional analysis software. JT measurements involved six opening–closing cycles, and JVA measurements were performed using a metronome to guide the mouth opening–closing movements of the patients. The correlations among the three measuring devices were evaluated. Results: Abnormalities in condylar surface morphology affected the mandibular range of motion. The cut-off value results show that when various measurement groups are within a certain range, abnormalities may be observed in morphology (area under the curve, 0.81; P < 0.001). A 300/< 300 Hz ratio ≥ 0.09 suggested abnormal morphology (P < 0.05). Correlations were observed among the maximum opening velocity, maximum vertical opening position, and joint spaces in the JT measurements. Correlations were also observed between the > 300/< 300 Hz ratio, median frequency, total integral, integral < 300 Hz, and peak frequency with joint spaces in the JVA measurements. Conclusions: JT and JVA may serve as rapid, non-invasive, and radiation-free dynamic diagnostic tools for monitoring and screening TMJ abnormalities before and during orthodontic treatment.