Orthodontics & Craniofacial Research最新文献

Objective: To evaluate the profile's attractiveness between the different protocols for treating the anterior open bite.

Methods: The sample comprised 39 patients with anterior open bite treated with or without extractions, divided into two groups: The surgical group (G1) comprised 21 subjects (10 males, 11 females) with a mean initial age of 21.86 years (SD = 5.09), treated with fixed orthodontic appliance followed by orthognathic surgery, for a total mean period of 2.53 years (SD = 0.61). The mean overbite was -5.01 mm (SD = 2.50); The camouflaged group (G2) comprised 18 subjects (9 males, 9 females), with a mean initial age of 20.47 years (SD = 4.19), treated only with fixed orthodontic appliance, for a total mean period of 2.56 years (SD = 0.94). The mean overbite was -4.28 mm (SD = 1.15). Lateral photographs from pretreatment and posttreatment were used. These photographs were evaluated by 46 laypeople and 67 dentists, who rated the attractiveness of each profile from 0 (most unattractive profile) to 10 (most attractive profile). Intergroup comparisons were performed with independent t-tests.

Results: Both groups presented improvement in the profile attractiveness with treatment (p < 0.001). Before treatment, the profile of the surgical group was significantly less attractive than the profile of the camouflaged group (p < 0.001). The surgical presented a more attractive profile at the final stage than the camouflaged group (p < 0.001). The surgical group showed a greater improvement in profile attractiveness with treatment than the camouflaged group (p < 0.001).

Conclusion: In the final stage, the surgical presented a more attractive and greater improvement in profile attractiveness than the camouflaged group. The laypeople and dentists judged similarly the initial profile attractiveness.

Intro: The aim of the current study was to develop and describe a new measuring system for the orientation of a tooth in a digitalized cast of a jaw and provide new angular values for the rotation, torque and tip of maxillary and mandibular teeth.

Methods: This retrospective cross-sectional study involved the utilization of a sub-group of extrinsic Euler-angles to derive optimal norm values per tooth in three different planes of orientation ('rotation', 'torque' and 'tip') by evaluating the digital representations of the teeth derived from a database containing over 17,500 patients. The process involved the entry of the .stl files of the jaw pairs into a fully automated software system (Smyl:Ai, Ulm, Germany) whereupon jaw alignment, teeth segmentation, landmark identification and visual validation of input files was conducted prior to calculation of the norm values for the three different planes of orientation.

Results: The digital scans in stereolithography (.STL)-file format of the upper and lower dentitions of 1914 individuals with optimal occlusion were chosen and evaluated. New mean (standard deviation) angular values were determined for the rotation, torque and tip of maxillary and mandibular teeth.

Conclusion: The findings facilitate the reappraisal of rotation, torque and tip values currently acceptable as ideal. They will inform anthropologists and dental researchers about occlusion and alignment in orthodontic and non-orthodontic patients and provide baseline data for future studies. The methodology will also enable the evaluation of large numbers of data in relatively short timeframes.

Aim: This study aimed to identify pretreatment cephalometric variables as possible predictors of the mandibular length increase in Class II patients with mandibular retrusion, treated by means of the Bite Jumping Appliance (BJA).

Materials and methods: Forty-three subjects (22 males and 21 females) with Class II malocclusion, treated with a BJA, were selected on the basis of the following inclusion criteria: full Class II molar relationship, Overjet (OVJ) ≥ 6 mm and a skeletal Class II malocclusion with mandibular retrusion at the start of the treatment (T0); cervical vertebral maturation stage 2 or 3 at time 0 (T0). The following mandibular structural features were measured on lateral cephalograms at time 0 and time 1 (15 months of treatment): the width and height of the mandibular symphysis and its width/height ratio, the width and height of the mandibular ramus and its width/height ratio, the antegonial notch depth and the Condilion-Gonion-Menton (Co-Go-Me) angle. Post-treatment changes were assessed by Pancherz's cephalometric analysis, evaluating the increases in mandibular length. A regression statistical model was used to test the association between morphologic variables and mandibular length changes.

Results: At T1, a significant increase in mandibular length (7.1 + 3.4 mm, p < .001) was measured. A significant negative association between the pretreatment Co-Go-Me angle and mandibular length change was found (p < .05). IMPA angle was negatively associated with mandibular length change. All the others morphological feature were not statistically related to mandibular length change.

Conclusion: Co-Go-Me angle and IMPA angle at T0 can be used as predictors for mandibular response to the treatment with BJA.

Photobiomodulation (PBM) has been demonstrated as a non-invasive and painless technique with great potential to accelerate orthodontic tooth movement (OTM). However, there is a great inconsistency among PBM protocols and reported outcomes, probably due to the poor translatability of preclinical knowledge into early clinical practice. Hence, this review aims to fill this gap by establishing the state-of-the-art on both preclinical and clinical applications of PBM, and by comprehensively discussing the most suitable stimulation protocols described in the literature. This review was conducted according to PRISMA guidelines. A bibliographic search was carried out in the PubMed, Scopus and Cochrane databases using a combination of keywords. Only studies written in English were eligible and no time limit was applied. A total of 69 studies were selected for this review. The revised literature describes that PBM can effectively reduce orthodontic treatment time and produce analgesic and anti-inflammatory effects. We found that PBM of 640 ± 25, 830 ± 20 and 960 ± 20 nm, delivered at a minimum energy density per irradiation point of 5 J/cm² daily or every other day sessions is robustly associated with increased tooth movement rate. Pain relief seems to be achieved with lower irradiation doses compared to those required for OTM acceleration. For the first time, the bioeffects induced by PBM for the acceleration of OTM are comprehensively discussed from a translational point of view. Collectively, the evidence from preclinical and clinical trials supports the use of PBM as a coadjuvant in orthodontics for enhancing tooth movement and managing treatment-associated discomfort. Overall, the revised studies indicate that optimal PBM parameters to stimulate tissue remodelling are wavelengths of 830 ± 20 nm and energy densities of 5-70 J/cm² applied daily or every other day can maximize the OTM rate, while lower doses (up to 16 J/cm² per session) delivered in non-consecutive days seem to be optimal for inducing analgesic effects. Future research should focus on optimizing laser parameters and treatment protocols customized for tooth and movement type. By fine-tuning laser parameters, clinicians can potentially reduce treatment times, improve patient comfort and achieve more predictable outcomes, making orthodontic care more efficient and patient-friendly, thus consolidating PBM usage in orthodontics.

Objective: Primary aim was to analyse dentoalveolar and skeletal effects induced by an anterior open bite (AOB) treatment protocol for intrusion of maxillary buccal segment. Secondary aim was to investigate whether a subsequent change occurred in hyoid position.

Materials and methods: Study group included 28 non-growing subjects treated in academic setting for correction of AOB. All patients received same appliance that included bilateral acrylic bite-blocks covering posterior dentition. Intrusive force was applied between buccal bars of appliance and zygomatic multipurpose implants. Lateral cephalograms taken at pre-treatment (T0) and after intrusion (T1) were analysed using NemoCeph software. Eight skeletal, 9 dental, 6 soft tissue and 5 hyoid parameters were measured and evaluated statistically.

Results: Mean open bite was -3.2 ± 2.1 mm at T0. T1-T0 duration was 9.6 ± 1.9 months. Increase in SNB (1.1° ± 2.1°) and the decrease in ANB (-1.1° ± 1.3°), Y-axis (-0.5° ± 3.5°), SN-GoGn (-2.0° ± -2.5°) and lower facial height (-1.4 ± 2.1 mm) were significant, indicating mandibular counter-clockwise rotation. Overjet and open bite decreased significantly (-1.8 ± 2.3 mm and 4.2 ± 2.1 mm, respectively). Maxillary molars intruded (U6-PP: -3.1 ± 1.3 mm) and distalised (ΔU6-TVL: -1.5 ± 2.7 mm) significantly. Mean change in L6-MP was significant (0.9 ± 1.4 mm) showing mandibular molar eruption. Lower lip-true vertical line (TVL) showed significant forward movement of lower lip (-1.8 ± 2.3 mm). Mean changes in hyoid parameters were not significant.

Conclusion: Significant maxillary buccal segment intrusion was achieved in a relatively short period. AOB was corrected while facial profile and smile aesthetics were improved. Distalisation of maxillary molar suggests that intrusive force vector can be modified to achieve simultaneous intrusion and distalisation.

Objectives: This study aimed to evaluate and compare the antibacterial properties and optical characteristics of clear orthodontic aligners coated with zinc oxide (ZnO) and magnesium oxide (MgO) nanoparticles.

Materials and methods: In this experimental laboratory study, polyethylene terephthalate glycol (PETG) aligner samples were coated with nanoparticles of ZnO, MgO and a combination of both (ZnO + MgO). The surface coatings were analysed before and after stability testing using field emission scanning electron microscopy (FESEM). Colour changes and translucency were measured using a spectrophotometer, and the antimicrobial and antibiofilm properties were evaluated against Streptococcus mutans and Lactobacillus species. Statistical analysis was conducted using SPSS, with significance set at p < 0.05.

Results: Significant statistical differences were found in the colour changes between the groups (p < 0.001), with the greatest change in MgO-coated aligners (0.94 ± 0.09), followed by ZnO + MgO (0.75 ± 0.05) and ZnO (0.5 ± 0.09). ZnO-coated aligners exhibited the highest translucency (47.6 ± 0.44) compared to MgO (45.07 ± 0.74) and ZnO + MgO (45.76 ± 0.7) (p = 0.002 and p = 0.026, respectively). Nanoparticle-coated aligners showed significantly reduced bacterial growth (p < 0.05). The ZnO + MgO combination demonstrated superior antibacterial effects compared to individual coatings. Nanoparticles remained stable after 24-h agitation in artificial saliva and brushing, maintaining 60%-65% stability.

Conclusion: The aligners coated with ZnO nanoparticles exhibited the least colour change and the highest translucency compared to those coated with MgO nanoparticles and the ZnO + MgO combination. The highest antibacterial properties were observed in the aligners coated with a combination of ZnO and MgO nanoparticles.

Objectives: This non-randomised clinical study aimed to identify the phenotypic characteristics that distinguish responders from non-responders. Additionally, it sought to establish a predictive model for treatment response to obstructive sleep apnoea (OSA) using mandibular advancement devices (MAD), based on the analysed phenotypic characteristics.

Material and methods: This study, registered under identifier NCT05596825, prospectively analysed MAD treatment over 6 years using two-piece adjustable appliances according to a standardised protocol. Two response definitions aligned with the latest International Consensus Statement on OSA severity were established. Logistic regression and CHAID models integrated baseline clinical, anthropometric, cephalometric anatomical, soft tissue characteristics and physiological upper airway variables.

Results: A total of 112 patients completed the study: 64 responders and 48 non-responders according to response definition 1, and 81 responders and 31 non-responders according to response definition 2. Responders to MAD treatment had lower body mass index (BMI), neck and waist circumference, Epworth Sleepiness Scale scores, apnoea-hypopnea index (AHI), snoring intensity on the Visual Analog Scale, CPAP pressure, and higher T90% and minSaO₂. Patients exhibiting greater anatomical imbalance, smaller airway volume, smaller minimum cross-sectional area (CSAmin) and longer airway length demonstrated a poorer response to treatment.

Conclusions: Airway length, initial T90% and anterior facial height collectively formed a highly predictive logistic regression model for response definition 1. Jarabak's ratio, gonial angle, CSAmin, airway length, initial BMI and baseline AHI constituted a highly predictive model for the second response definition. Furthermore, the CHAID regression tree established cutoff values for the variables that form the predictive models.

Background: Orthodontic treatment need has commonly been assessed using treatment need indices during clinical examinations or using photographs in combination with plaster casts. Recently, the use of intraoral photographs alone to screen malocclusions has increased.

Objective: This study aimed to validate intraoral photographs for the assessment of orthodontic treatment need.

Materials and methods: The study sample consisted of case files from 30 pre-orthodontic patients aged 12-19 years. Each case file included intraoral photographs and casts. The cases were consecutively recruited from two orthodontic treatment waiting lists: 15 from the Department of Orthodontics at Folktandvården Eastmaninstitutet, Stockholm, Sweden and 15 from the Center for Orthodontics and Pediatric Dentistry, Norrköping, Public Dental Service Östergötland. Their orthodontic treatment need was assessed by four raters (calibrated orthodontists) using the indices IOTN-AC, IOTN-DHC, ICON, and DAI. The four raters individually assessed the 30 cases on three occasions: (1) photos only, (2) photos and casts, and (3) photos only. Finally, the four raters jointly made a consensus assessment using both photos and casts. For IOTN-AC and IOTN-DHC, interrater agreement was assessed with Fleiss' kappa, and validity with the Wilcoxon signed-rank test. For ICON and DAI, interrater agreement was assessed with Intra Class Correlation (ICC) (1, 2) and validity with a paired t-test.

Results: Interrater agreement for IOTN-AC was slight (0.14-0.18) and moderate for IOTN-DHC (0.51-0.57), regardless of whether photographs were used alone or combined with casts. ICON demonstrated moderate interrater agreement (0.57-0.72), while DAI showed moderate to excellent (0.70-0.91), similarly unaffected by the use of photographs alone or in combination with casts. The validity analysis, which compared the individual assessments to the consensus one, revealed equivalent differences whether the assessment involved intraoral photographs alone or in combination with casts.

Conclusion: Intraoral photographs are sufficient for assessing orthodontic treatment need because interrater agreement and validity are similar whether photos are used alone or with casts. However, interrater variability was substantial for both assessment methods.

Trial registration: ClinicalTrial.gov. identifier: NCT05038865.

Objectives: Radiographs are routinely acquired for orthodontic evaluation, and incidental findings (IFs) may be detected early as part of this routine care. This study aimed to assess the prevalence of IFs on panoramic radiographs taken for orthodontic assessment and evaluate the ability of orthodontists to detect, interpret and recommend management for IFs.

Materials and methods: A retrospective analysis of 1756 patients aged 7-21 with a panoramic image taken for orthodontic evaluation was performed. IFs were categorised by anatomic region and assigned a significance level based on a custom-made risk assessment tool. Twelve selected images were evaluated by 30 orthodontists via a standardised online survey. Participants were tasked with reviewing each image, providing a radiological interpretation, and indicating whether a referral would be needed prior to commencing orthodontic treatment. The responses were scored against those of an expert oral and maxillofacial radiologist (OMFR). Inter-observer agreement was evaluated by computing the Cohen's K.

Results: The prevalence of IFs was 30.8%. The most common findings were impacted teeth (17.7%), hypodontia (14.9%) and dense bone islands (14.7%). After applying the risk assessment tool, 35% of the findings were considered highly significant. The overall agreement between the orthodontists and OMFR was k = 0.32 (95% CI = 0.30-0.34). The agreement for location was 0.52 (95% CI = 0.47-0.58), whereas it was k = 0.45 (95% CI = 0.40-0.50) for diagnosis and k = 0.19 (95% CI = 0.13-0.24) for referral need.

Conclusions: Orthodontists may benefit from additional education and training focused on interpretation and management of IFs on panoramic radiographs.

Objective: This retrospective study aims to assess the predictability of Overbite (OVB) reduction and Curve of Spee (COS) levelling in patients with deep bite malocclusion treated with Clear Aligner Therapy (CAT). The research evaluates the accuracy of the prescribed movements in growing and non-growing patients.

Materials and methods: Thirty-six patients treated with Invisalign from January 2018 using SmartTrack were included. Digital models at pre-treatment, virtual plan and post-treatment phases were collected and analysed using Geomagic Control X. Accuracy was assessed for COS levelling, OVB reduction and individual tooth movements. Statistical analyses included descriptive statistics, paired t-tests and linear regression between accuracy of the movements and the age of the patient.

Results: The study found that the prescribed movements in ClinCheck often overestimated the achieved outcomes. The mean accuracy for COS levelling was 62%, and for OVB reduction, it was 61%. No significant association was observed between the accuracy and the age of the patient.

Conclusion: Clear Aligner Therapy demonstrated moderate accuracy in achieving prescribed movements for COS levelling and OVB reduction. Clinicians should exercise caution in virtual treatment planning and may need to consider potential modifications to software projections to enhance desired outcomes. Further research comparing different aligner protocols and brands is warranted to advance understanding and improve treatment predictability.