Clinical and histological evaluation of the effect of magnesium oxide administration on relapse after orthodontic teeth movement (Rabbit Model Study).

OBJECTIVE: This study aimed to evaluate the clinical and histological administration of magnesium oxide (MgO) supplementation on orthodontic relapse and bone remodeling. MATERIALS AND METHODS: Twenty male albino rabbits were classified into four groups (five animals for each as two control (positive and negative), plus two experimental (low dose 40 mg/kg) and (high dose 80 mg/kg)/b.w. daily). An orthodontic force was applied (40 gm) to the lower incisors using modified orthodontic appliance adapted on the lower central incisors. During the period of retention, MgO was given orally. Relapse was estimated after appliance removal. A digital Calliper was used to compete the space between incisors' mesial tips of rabbits at six successive time points (0, 3, 7, 10, 15, and 21 days). Histologically, osteoblast, osteoclast, and osteocyte account were assessed. Data analyses were performed by SPSS using ANOVA and Tukay HSD (P ≤ 0.05) for statistically significant differences between groups. RESULTS: The high dose group had a lower relapse rate than the low dose and control groups. Histologically, the high dose group had more osteoblasts and osteocytes than low dose and control groups. While osteoclasts were significantly lower than the control group in low and high dose groups. CONCLUSIONS: MgO supplementation during an orthodontic retention phase, particularly at a level of high dose, clinically decreased orthodontic relapse in a rabbit model. Histologically, MgO has a significant effect on alveolar bone after the orthodontic retention period.

The efficacy and accuracy of 3D-guided orthodontic piezocision: a randomized controlled trial.

BACKGROUND: No randomized controlled trial (RCT) has studied the accuracy of surgical guides used in terms of orthodontic treatment acceleration. Therefore the aim of this trial was to assess computer-guided piezocision-based orthodontic. MATERIALS AND METHODS: Thirty-two patients with severely crowded upper anterior teeth were enrolled and randomly allocated to either the experimental group (ExpG) or the control one. Subjects of the ExpG received three-dimensional (3D) guided piezoelectric corticotomies on the buccal alveolar bone of the anterior region. Five piezocision cuts were properly performed between each anterior teeth and the adjacent in virtual models. Surgical guides were designed and 3D-printed with preplanned slots that guide gingival and then piezoelectric incisions. The patients underwent Cone-Beam Computed Tomography CBCT before and immediately after surgery. Thus, Predesigned piezocisions were compared to the actual ones in attempt to measure three dimensional deviations of the applied peizocisions. RESULTS: Ninety-six severe maxillary dental crowding were assigned for eligibility, 40 of them met the inclusion criteria. Thirty-two participants were randomly allocated to the trial`s groups. No patient was lost to follow-up neither from the control nor the experimental group. Overall alignment time (OAT) was reduced by 53% in the experimental group compared to the control group. The mean of the 3D deviation of the surgical guide was 0.23 mm (standard deviation 0.19 mm). CONCLUSION: The values of the surgical guide deviation was nearly null, which confirms that this innovative technique is clinically applicable. Furthermore, this technique was impressively effective in accelerating orthodontic tooth movement. TRIAL REGISTRATION: This trial was registered at The ISRCTN registry (ID: ISRCTN65498676 Registration date: 07/04/2021).

Orthodontic program design based on aesthetic.

Orthodontics is a discipline that is based on aesthetics. It coordinates the relationship among nose, lip, and chin through the movement of teeth and the adjustment of jaw relationship. Orthodontists need to fully analyze the patient's soft tissue profile before treatment. They also need to analyze the existing problems and those that may be solved or caused during orthodontics to guide the design of orthodontic treatment and effectively improve the clinical effect of orthodontics. This article reviews the aesthetic preconditions that guide the design of orthodontic treatment from the perspective of orthodontists.

Effect of the photobiomodulation for acceleration of the orthodontic tooth movement: a systematic review and meta-analysis.

To determine whether the application of photobiomodulation (PBM), as an adjunctive treatment for patients with orthodontic fixed appliances, decreased the total treatment time compared to conventional orthodontics. Studies were collected from four electronic databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for systematic reviews. Eligibility criteria were full-text articles in English or Spanish with the design of randomized (RCT), non-randomized clinical trials (non-RCT), and retrospective cohort, without any restriction regarding the publication time, in which the effect of PBM using low-level laser irradiation (LLLI) and light-emitting diode (LED) for the acceleration of the orthodontic movement had been evaluated. Data collection and analysis: Two authors independently extracted data for the characteristics and outcomes of the studies selected for inclusion. The risk of bias (RoB 2 and Robins-I) and the quality assessments (GRADE) were performed. For the quantitative synthesis, the standardized mean difference was calculated for each individual study selected and then the data were combined using a random-effects meta-analysis. The total number of included studies was n = 22 (only RCT and non-RCT were found) with a total of 515 participants. The included studies exhibited high risk of bias and some concerns, though none of them presented a low risk of bias. The quality of the studies was very low. The meta-analysis showed that the means (mm) and 95% confidence intervals (95% CI) of acceleration of tooth movement at 1, 2, and 3 months were 0.50 (- 0.28, 1.28), 1.40 (0.27, 2.53), and 0.46 (- 0.33, 1.24), respectively. The analysis showed that there is no evidence to support the use of LLLI to accelerate the orthodontic movement. LED for the acceleration of orthodontic movement does not have sufficient evidence to generate conclusions about it.

Consistency and Reliability Analyses of a Comprehensive Index for the Evaluation of Teeth Alignment Performance.

(1) Introduction: The purpose of this work was to describe a method and propose a novel accuracy index to assess orthodontic alignment performance. (2) Methods: Fifteen patients who underwent orthodontic treatment using directly printed clear aligners were recruited. The study sample included 12 maxillary and 10 mandibular arches, whose pre-treatment, predicted and post-treatment digital models were superimposed on the untreated posterior teeth by means of a best-fit surface-based registration, which was also used to transfer three anatomical landmarks, digitally labeled on the crown of each anterior moving tooth, from the pre-treatment to the predicted and post-treatment models. The Teeth Alignment Performance (TAP) index, quantifying how close the final landmarks were to their expected final position, was proposed as an accuracy index of both individual tooth and group of teeth movement, and its inter-examiner repeatability was tested. (3) Results: No systematic inter-rater discrepancy associated with TAP was observed (p > 0.05), not even when a slight systematic inter-rater difference in landmark labelling was detected (for the upper central incisors, p < 0.001). In addition, all Intra-class Correlation Coefficient (ICC) values showed excellent inter-rater agreement (>0.95), and the small Random Error of Measurement (REM), ranging from 1% for the arch TAP to 3% for the lower canine TAP, indicated that this accuracy index is highly repeatable. (4) Conclusions: The TAP index was proven to be comprehensive, consistent and reliable in assessing the performance of teeth alignment according to a digital plan. The proposed method is also suitable to be implemented in the clinical digital workflow.

The Shape of Nasopalatine Canal as a Determining Factor in Therapeutic Approach for Orthodontic Teeth Movement-A CBCT Study.

The aim of this study was to evaluate the impact of the nasopalatine canal (NPC) shape and its morphometric characteristics on expected teeth movement by assessing the distance to maxillary central incisors (MCIs) according to NPC type. The retrospective study was performed on 133 CBCT images. The following parameters were obtained: the antero-posterior diameter (A-P) of the nasal foramen (NF), canal length, A-P and mediolateral diameter (M-L) of the incisive foramen (IF), and the distance between NPC and MCIs. With the exception of being hourglass-shaped, each NPC shape showed specific impacts of NPC shape on the relationship between NPC diameters at different sections and distances to MCIs. In banana-shaped NPC, a significant correlation was observed for A-P NF diameter, while in cylindrical-shaped NPC, a significant correlation was observed for NPC length. The increase in M-L IF, A-P IF, A-P NF, and NPC length in funnel-shaped NPC may be a risk factor for interventions that could result in teeth movement. According to the results, it seems that the proposed methodological approach for analysis of CBCT slices in the anterior maxilla may offer detailed information that could be an additional tool in planning the procedures that result in expected teeth movement.

[Complex orthodontic-surgical rehabilitation of adults with malocclusions and deformations in dentition]. / Kombinirovannoe ortodonto-khirurgicheskoe lechenie vzroslykh patsientov s zubochelyustnymi anomaliyami i deformatsiyami zubnykh ryadov.

The aim of the study was the development and substantiation of the method of orthodontic treatment of patients with malocclusions and deformities of dentoalveolar arches with the combined use of braces, orthodontic miniscrew, piezo-surgical corticotomy or laser corticotomy to improve the efficiency and reduce the time of complex treatment. The results of complex rehabilitation of 80 adult patients with dentoalveolar anomalies and deformities of dentition are presented. As a result of the orthodontic treatment of patients who underwent piezo-surgical corticotomy the bodily movement of the posterior teeth in the area of the previously removed tooth was achieved. After piezo-surgical or laser corticotomy the rate of tooth protraction remained elevated for 3 to 5 months (on average 0.3±0.5 mm/month), then gradually decreased. Piezo-surgical corticotomy led to a decrease in bone density, which was measured on the Hounsfield scale. As a result of orthodontic treatment in patients who underwent laser corticotomy an expansion of the upper jaw and normalization of occlusion in the transversal and sagittal directions was achieved: in the region of the hard palate by 7.1±0.4 mm; in the region of the alveolar bone by 6.5±0.5 mm; in the region of the roots of molars by 6.4±0.9 mm; in the area of crowns of molars by 8.3±0.7 mm. It was found that the combined use of piezo-surgical corticotomy and orthodontic miniscrews improve the efficiency and reduce the duration of orthodontic treatment by 3 to 6 months.

[The mesialization of molars of the lower jaw after performance surgical manipulation with using miniscrew anchorage approach]. / Mezializatsiia moliarov s pomoshch'iu breket-sistemy posle provedeniia p'ezokortikotomii.

Process of the mesialization of molars in the lower jaw is long-time, moreover the molars are not frequently bodily translation. Conduction of the corticotomy reduce to regional acceleration phenomen that permit to accelerate the tooth movement avoiding negative inclination. PURPOSE: To improve the effectiveness of the treatment using piezocorticotomy and miniscrew anchorage approach in cases of third and second molar mesialization when first molar is missing. MATERIAL AND METHODS: 24 patients (10 men/14 women) aged 25-40 years with a fixed vestibular braces and the absence of molars on the lower jaw. Cone-beam computed tomography was performed before and after orthodontic treatment, as well as immediately after the piezokortikotomy (79 Cone-beam computed tomography). Miniscrews was placed in the area between roots of the first and second premolars (27 miniscrews) and surgical manipulations was performed using device VarioSurg (NSK, Japan). Depending on width of the alveolar ridge piezocorticotomy was performed (16 piezocorticotomies) or splitting using piezosurgery approach (11 splitting). RESULTS: Mesialization speed of molars in patients with support of piezocorticotomy is equal to 1.1±0.1 mm/mo that is higher than in patients without surgery only with miniscrew approach (0.33±0.006 mm/mo Roberts et al, 1996). Mesialization speed of molars in patients with support of splitting is equal to 1.6±0.15 mm/mo. However, we observed that after corticotomies surgery, the speed was increased only within the first 4.5 months, after splitting, the speed was increased only withing 2.5 months, after that period the speed gradually decreases. Bone density after surgery decreased, but at the end of treatment gradually restored. CONCLUSION: Piezo surgery with corticotomies is an effective method to accelerate the mesialization of molars in the lower jaw, that conduce to reduction duration the treatement and to allow to almost bodily translation of the molars.