Caries detection and characterization in pediatric patients using iTero 5D near-infrared technology.

INTRODUCTION: Near-infrared imaging (NIRI) has been proposed as an alternative to radiographs and uses nonionizing radiation in the near-infrared spectrum to differentially scatter light off tooth surfaces and generate images allowing interproximal caries detection. The new iTero 5D Element Scanner (Align Technology, Santa Clara, Calif) has integrated NIRI capture and viewing technology but has not been specifically studied in a pediatric population. Therefore, this study aimed to assess clinicians' abilities to detect and characterize caries in pediatric patients using this instrument. METHODS: Bitewing (BW) radiographs and an intraoral scan were captured on 17 pediatric patients (344 surfaces were analyzed). Data were randomized and graded by 5 calibrated clinicians individually with 2 different rounds of grading. RESULTS: The reliability of lesion characterization (ie, grade) among examiners was poor to fair in both systems, whereas the reliability of caries detection was moderate. Both systems had a high specificity and low sensitivity. The reliability of the characterization of the combined dataset was moderate to substantial, whereas, for detection, it was substantial. CONCLUSIONS: When using either BW or NIRI analysis, reliability is relatively poor, and clinicians are more likely to correctly identify a healthy tooth surface when compared with a carious surface. There is a small difference in error rate between BW and NIRI systems that is not likely to be clinically significant. When NIRI and BW data are combined, clinician agreement for both lesion characterization and detection increases significantly.

Cross-sectional data accurately model longitudinal growth in the craniofacial skeleton.

Dense, longitudinal sampling represents the ideal for studying biological growth. However, longitudinal samples are not typically possible, due to limits of time, prohibitive cost, or health concerns of repeat radiologic imaging. In contrast, cross-sectional samples have few such drawbacks, but it is not known how well estimates of growth milestones can be obtained from cross-sectional samples. The Craniofacial Growth Consortium Study (CGCS) contains longitudinal growth data for approximately 2000 individuals. Single samples from the CGCS for individuals representing cross-sectional data were used to test the ability to predict growth parameters in linear trait measurements separately by sex. Testing across a range of cross-sectional sample sizes from 5 to the full sample, we found that means from repeated samples were able to approximate growth rates determined from the full longitudinal CGCS sample, with mean absolute differences below 1 mm at cross-sectional sample sizes greater than ~ 200 individuals. Our results show that growth parameters and milestones can be accurately estimated from cross-sectional data compared to population-level estimates from complete longitudinal data, underscoring the utility of such datasets in growth modeling. This method can be applied to other forms of growth (e.g., stature) and to cases in which repeated radiographs are not feasible (e.g., cone-beam CT).

Short-term stability of anterior open bite treatment with clear aligners in adults.

INTRODUCTION: This study aimed to examine the stability of anterior open bite (AOB) treatment with clear aligners. METHODS: This retrospective cohort study included 52 adult AOB patients (aged >18 years; 15 males, 37 females) who underwent nonextraction clear aligner treatment and were at least 1 year posttreatment. Eleven cephalometric measurements were evaluated at pretreatment, end of active treatment, and at least 1-year posttreatment. Overbite change, the primary outcome variable, and other cephalometric changes during treatment and retention were calculated, and repeated measures analysis of variance were performed. Stepwise multiple regression was used to make a prediction equation for open bite relapse. RESULTS: The mean retention period was 2.1 ± 1.1 years. The mean change in overbite during treatment was 3.3 ± 1.5 mm; 6% of patients presented relapse at least 1 year after treatment completion. The mean change of overbite (0.2 ± 0.5 mm) during the retention period was not statistically significant (P = 0.59). None of the 11 cephalometric measurements showed significant change during the retention period. The prediction model showed that only the coefficient for a tongue posture issue at the initial examination was statistically significant. CONCLUSIONS: AOB was successfully corrected in all 52 patients using only clear aligners with no additional adjunctive aids such as microimplants. When retained with maxillary and mandibular fixed retainers and maxillary and mandibular vacuum-formed retainers, there was no significant change in cephalometric measurements during the short-term retention period.

Three-dimensional decision support system for treatment of canine impaction.

INTRODUCTION: This study aimed to develop a 3-dimensional (3D) characterization of the severity of maxillary impacted canines and to test the clinical performance of this characterization as a treatment decision support tool. METHODS: Cone-beam computed tomography images obtained from 83 patients with 120 impacted maxillary canines were included. Quantitative information on the canine 3D position and qualitative assessment of root damage of adjacent teeth were evaluated. A severity index was constructed on the basis of the quantitative findings. Clinical applicability was tested by comparing clinical diagnosis and treatment planning for conventional records vs the 3D characterization via a 2-part survey. RESULTS: The average quantitative assessments of impacted maxillary canine position were 6.4 ± 3.6 mm from the midsagittal plane, 11.6 ± 3.1 mm in height relative to the occlusal plane, 31.5° ± 18° of roll, and 48.8° ± 14.3° of pitch. The severity index ranged from 0-13 with a mean score of 4.5 ± 2.2. Overlap with adjacent teeth was the greatest contributor (33%) to the index. Bicortically impacted canines caused the most severe root damage. Cone-beam computed tomography was preferred for assessing root damage and overall severity, whereas conventional imaging was sufficient for height and angulation assessment. The 3D report was very important or important for evaluating root damage, canine position, overall severity, and overlap. The 3D report changed most of the decisions relating to biomechanics, patient education, and treatment time estimate. The decision of exposure and traction vs extraction was changed 22% of the time after the presentation of the 3D report. CONCLUSIONS: The overlap with adjacent teeth frequently contributes the most to the severity index. The 3D report provided relevant clinical information regarding the canine position, damage to adjacent teeth, and the severity index, with a profound impact on the decisions of the clinicians regarding biomechanics, patient education, and treatment time estimate.

Survival rates of mandibular fixed retainers: comparison of a tube-type retainer and conventional multistrand retainers : A prospective randomized clinical trial.

OBJECTIVE: The purposes of this study were to evaluate the survival rate of a tube-type mandibular fixed retainer and compare it to conventional multistrand retainers. MATERIALS AND METHODS: In all, 66 patients who had completed their orthodontic treatment were enrolled in this study. They were allocated randomly to a tube-type retainer group or a 0.020 multistrand fixed retainer group. In case of the tube-type retainer, a thermoactive 0.012 NiTi was placed into 6 mini-tubes passively bonded to the anterior teeth. The patients were recalled at 1, 3, 6, 12, and 24 months after retainer placement. During the 2­year follow-up period, any first-time failure of retainers was recorded. Kaplan-Meier survival analysis and log-rank tests were used to compare the failure rates between the two types of retainers. RESULTS: Of the 34 patients, 14 (41.2%) showed failure in the multistrand retainer group, whereas only 2 of 32 (6.3%) reported failure in the tube-type retainer group. There was a statistically significant difference in failure between the multistrand retainer and the tube-type retainer (log-rank test, P = 0.001). The hazard ratio was 11.937 (95% confidence interval 2.708-52.620; P = 0.005). CONCLUSION: The tube-type retainer can be used with fewer concerns about recurrent retainer detachments during orthodontic retention.

What changes in maxillary morphology from distraction osteogenesis maxillary expansion (DOME) correlate with subjective and objective OSA measures?

OBJECTIVES: To correlate skeletal and airway measures on imaging with polysomnographic and self-reported measures after distraction osteogenesis maxillary expansion (DOME), in the effort to identify clinically relevant sites of expansion to guide treatment for adult patients with obstructive sleep apnea (OSA). MATERIALS AND METHODS: This is a retrospective study reviewing subjects who underwent DOME and had the complete set of the following data: peri-treatment cone-beam computed tomography (CBCT) scans, polysomnography (PSG), Epworth Sleepiness Scale (ESS), and nasal obstruction symptom (NOSE) scores. RESULTS: Of 132 subjects who underwent DOME, 35 met inclusion criteria (71% men, mean age 27.7 ± 6.5 years, mean BMI 26.0 ± 6.4 kg/m2) and were enrolled in the study. There was a significant reduction in the NOSE score from 11.4 ± 5.5 to 3.6 ± 3.1, in the ESS score from 12.0 ± 4.6 to 7.1 ± 4.7, and in the apnea-hypopnea index (AHI) from 17.1 ± 15.8 to 7.01 ± 6.2 (p < 0.0001), after DOME. Nasal floor width at the nasopalatine canal level showed a statistically significant correlation with AHI reduction (p < .0001). CONCLUSIONS: DOME is significantly associated with reduction of nasal obstruction, sleepiness, and severity of OSA. The findings suggest that expansion at the anterior third of the bony nasal passage, specifically where the nasopalatine canal is located predicts its clinical efficacy. This site may be a useful target anatomically via imaging.

Three-dimensional digital applications for implant space planning in orthodontics: A narrative review.

In the digital dentistry era, new tools, algorithms, data science approaches, and computer applications are available to researchers and clinicians. However, there is also a strong need for better knowledge and understanding of multisource data applications, including three-dimensional imaging information such as cone-beam computed tomography images and digital dental models for multidisciplinary cases. In addition, artificial intelligence models and automated clinical decision systems are rising. The clinician needs to plan the treatment based on state-of-the-art diagnosis for better and more personalized treatment. This article aimed to review basic concepts and the current panorama of digital implant planning in orthodontics, with open-source and closed-source tools for assessing cone-beam computed images and digital dental models. The visualization and processing of the three-dimensional data allow better implant planning based on bone conditions, adjacent teeth and root positions, and the prognosis of the case. We showed that many tools for assessment, segmentation, and visualization of cone-beam computed tomographic images and digital dental models could facilitate the treatment planning of patients needing implants or space closure. The tools and approaches presented are toward personalized treatment and better prognosis, following the path to a more automated clinical decision system based on multisource three-dimensional data, artificial intelligence models, and digital planning. In summary, the orthodontist needs to analyze each patient individually and use different software or tools that better fit their practice, allowing efficient treatment planning and satisfactory results with an adequate prognosis.

Automatic multi-anatomical skull structure segmentation of cone-beam computed tomography scans using 3D UNETR.

The segmentation of medical and dental images is a fundamental step in automated clinical decision support systems. It supports the entire clinical workflow from diagnosis, therapy planning, intervention, and follow-up. In this paper, we propose a novel tool to accurately process a full-face segmentation in about 5 minutes that would otherwise require an average of 7h of manual work by experienced clinicians. This work focuses on the integration of the state-of-the-art UNEt TRansformers (UNETR) of the Medical Open Network for Artificial Intelligence (MONAI) framework. We trained and tested our models using 618 de-identified Cone-Beam Computed Tomography (CBCT) volumetric images of the head acquired with several parameters from different centers for a generalized clinical application. Our results on a 5-fold cross-validation showed high accuracy and robustness with a Dice score up to 0.962±0.02. Our code is available on our public GitHub repository.

Comparison between a human judge and automatic landmark identification on digital models.

INTRODUCTION: Accurate landmark identification is a prerequisite for accurate and reliable biomedical image analysis. Orthodontic study models are valuable tools for diagnosis, treatment planning, and maintaining complete records. The purpose of this study was to evaluate the reliability and validity of a software program (Align Technology, Inc) as a tool for automatic landmark location. METHODS: Using digital intraoral scans of 10 dental arches, 4 calibrated human judges independently located cusp tips and interproximal contacts. The same landmarks were automatically identified by the software. Intraclass correlation coefficient (Cronbach α), absolute mean errors, and regression analysis were calculated. In addition, Bland-Altman 95% confidence limits were also applied to the data to graphically display agreement on landmark identification between the human judges and the software. RESULTS: The intraclass correlation coefficient between the software and the human judges' average for the x-, y-, and z-coordinates for all landmarks was excellent, at 1.0, 1.0, and 0.98, respectively. The regression analysis and Bland-Altman plots show no systematic errors for agreement on landmark identification between the human judges and the software. CONCLUSIONS: Landmark location was nearly identical between the software and the human judges, making the methods interchangeable.

Automated landmark identification on cone-beam computed tomography: Accuracy and reliability.

OBJECTIVES: To evaluate the accuracy and reliability of a fully automated landmark identification (ALI) system as a tool for automatic landmark location compared with human judges. MATERIALS AND METHODS: A total of 100 cone-beam computed tomography (CBCT) images were collected. After the calibration procedure, two human judges identified 53 landmarks in the x, y, and z coordinate planes on CBCTs using Checkpoint Software (Stratovan Corporation, Davis, Calif). The ground truth was created by averaging landmark coordinates identified by two human judges for each landmark. To evaluate the accuracy of ALI, the mean absolute error (mm) at the x, y, and z coordinates and mean error distance (mm) between the human landmark identification and the ALI were determined, and a successful detection rate was calculated. RESULTS: Overall, the ALI system was as successful at landmarking as the human judges. The ALI's mean absolute error for all coordinates was 1.57 mm on average. Across all three coordinate planes, 94% of the landmarks had a mean absolute error of less than 3 mm. The mean error distance for all 53 landmarks was 3.19 ± 2.6 mm. When applied to 53 landmarks on 100 CBCTs, the ALI system showed a 75% success rate in detecting landmarks within a 4-mm error distance range. CONCLUSIONS: Overall, ALI showed clinically acceptable mean error distances except for a few landmarks. The ALI was more precise than humans when identifying landmarks on the same image at different times. This study demonstrates the promise of ALI in aiding orthodontists with landmark identifications on CBCTs.

Treatment of anterior open bites using non-extraction clear aligner therapy in adult patients.

Objective: The purpose of this study was to examine the effectiveness and mechanism of clear aligner therapy for the correction of anterior open bite in adult nonextraction cases. Methods: Sixty-nine adult patients with anterior open bite were enrolled and classified into Angle's Class I, II, and III groups. Fifty patients presented with skeletal open bite (mandibular plane angle [MPA] ≥ 38°), whereas 19 presented with dental open bite. Fifteen cephalometric landmarks were identified before (T1) and after (T2) treatment. The magnitudes of planned and actual movements of the incisors and molars were calculated. Results: Positive overbite was achieved in 94% patients, with a mean final overbite of 1.1 ± 0.8 mm. The mean change in overbite was 3.3 ± 1.4 mm. With clear aligners alone, 0.36 ± 0.58 mm of maxillary molar intrusion was achieved. Compared with the Class I group, the Class II group showed greater maxillary molar intrusion and MPA reduction. The Class III group showed greater mandibular incisor extrusion with no significant vertical skeletal changes. Conclusions: Clear aligners can be effective in controlling the vertical dimension and correcting mild to moderate anterior open bite in adult nonextraction cases. The treatment mechanism for Class III patients significantly differed from that for Class I and Class II patients. Maxillary incisor extrusion in patients with dental open bite and MPA reduction with mandibular incisor extrusion in patients with skeletal open bite are the most significant contributing factors for open bite closure.

Condylar degeneration in anterior open bite patients: A cone beam computed tomography study.

OBJECTIVES: The purpose of this study was to investigate the prevalence of condylar degeneration in patients with anterior open bites (AOB). STUDY DESIGN: Cone beam computed tomography (CBCT) scans of 194 patients with AOB (108 with skeletal open bites and 86 with dental open bites) and 100 patients serving as controls were included in this retrospective study. Two oral and maxillofacial radiologists categorized each of the 588 condyles as normal, degenerative-active, or degenerative-repair. The χ2 analysis with Bonferroni adjustment was used to evaluate the relationship of condylar status (normal vs degenerative) to anterior open bites. RESULTS: Of the 103 degenerative condyles, there were 59 in the group with skeletal open bites, 14 in the group with dental open bites, and 30 in the control group. Condylar degeneration occurred twice as frequently in patients with skeletal open bites as it did in the control group (P < .0001). Conversely, a greater frequency of normal condyles was found in the group of patients with dental open bites (P = .0002). The group with skeletal open bites also showed a significantly higher frequency of bilateral degenerative condyles (P = .0001). The frequency of condylar degeneration did not differ significantly between female and male individuals. CONCLUSIONS: Degenerative condylar change was significantly more likely in patients with skeletal open bites and less likely in patients with dental open bites.

Effects of long-term use of the lower lingual arch from 8.5 years to 13.2 years.

OBJECTIVES: To investigate the effects of long-term use of the lower lingual arch (LLA) on the sagittal and vertical positions of the permanent lower incisors and first molars. MATERIALS AND METHODS: The sample consisted of 98 patients who were treated with an LLA (LLA group) and 39 patients who were treated without an LLA (no-LLA group). The positional changes of the lower incisors and first molars were analyzed after performing mandibular structural superimpositions on lateral cephalometric radiographs taken before treatment (T1) and at the end of LLA therapy (T2). The mean ages at T1 and T2 were 8.5 years and 13.2 years, respectively. Study casts were analyzed to quantify arch dimensional changes. RESULTS: Mesial movement of the lower molar cusp was similar between the LLA and no-LLA groups, but the vertical position was slightly greater at T2 in the LLA group. In the LLA group, there was a molar tip-back effect, and the lower incisors were proclined 4.2° more than in the no-LLA group. Arch perimeter decreased 3.6 ± 2.6 mm without an LLA and 0.97 ± 3.7 mm with an LLA. Intercanine and intermolar widths both increased about 1 mm more with an LLA (P < .0001). CONCLUSIONS: The LLA does not seem to restrict mesial movement and vertical eruption of the lower incisors and molars in the long term. The LLA effectively preserves the arch perimeter at the expense of a slight lower incisor proclination.

Automatic Segmentation of Mandibular Ramus and Condyles.

In order to diagnose TMJ pathologies, we developed and tested a novel algorithm, MandSeg, that combines image processing and machine learning approaches for automatically segmenting the mandibular condyles and ramus. A deep neural network based on the U-Net architecture was trained for this task, using 109 cone-beam computed tomography (CBCT) scans. The ground truth label maps were manually segmented by clinicians. The U-Net takes 2D slices extracted from the 3D volumetric images. All the 3D scans were cropped depending on their size in order to keep only the mandibular region of interest. The same anatomic cropping region was used for every scan in the dataset. The scans were acquired at different centers with different resolutions. Therefore, we resized all scans to 512×512 in the pre-processing step where we also performed contrast adjustment as the original scans had low contrast. After the pre-processing, around 350 slices were extracted from each scan, and used to train the U-Net model. For the cross-validation, the dataset was divided into 10 folds. The training was performed with 60 epochs, a batch size of 8 and a learning rate of 2×10-5. The average performance of the models on the test set presented 0.95 ± 0.05 AUC, 0.93 ± 0.06 sensitivity, 0.9998 ± 0.0001 specificity, 0.9996 ± 0.0003 accuracy, and 0.91 ± 0.03 F1 score. This study findings suggest that fast and efficient CBCT image segmentation of the mandibular condyles and ramus from different clinical data sets and centers can be analyzed effectively. Future studies can now extract radiomic and imaging features as potentially relevant objective diagnostic criteria for TMJ pathologies, such as osteoarthritis (OA). The proposed segmentation will allow large datasets to be analyzed more efficiently for disease classification.

The Significance of Utilizing A Corticotomy on Periodontal and Orthodontic Outcomes: A Systematic Review and Meta-Analysis.

PURPOSE: This systematic review compares the clinical and radiographic outcomes for patients who received only a corticotomy or periodontal accelerated osteogenic orthodontics (PAOO) with those who received a conventional orthodontic treatment. METHODS: An electronic search of four databases and a hand search of peer-reviewed journals for relevant articles published in English between January 1980 and June 2021 were performed. Human clinical trials of ≥10 patients treated with a corticotomy or PAOO with radiographic and/or clinical outcomes were included. Meta-analyses were performed to analyze the weighted mean difference (WMD) and confidence interval (CI) for the recorded variables. RESULTS: Twelve articles were included in the quantitative analysis. The meta-analysis revealed a localized corticotomy distal to the canine can significantly increase canine distalization (WMD = 1.15 mm, 95% CI = 0.18-2.12 mm, p = 0.02) compared to a conventional orthodontic treatment. In addition, PAOO also showed a significant gain of buccal bone thickness (WMD = 0.43 mm, 95% CI = 0.09-0.78 mm, p = 0.01) and an improvement of bone density (WMD = 32.86, 95% CI = 11.83-53.89, p = 0.002) compared to the corticotomy group. CONCLUSION: Based on the findings of the meta-analyses, the localized use of a corticotomy can significantly increase the amount of canine distalization during orthodontic treatment. Additionally, the use of a corticotomy as a part of a PAOO procedure significantly increases the rate of orthodontic tooth movement and it is accompanied by an increased buccal bone thickness and bone density compared to patients undergoing a conventional orthodontic treatment.

Geometric morphometric analysis of growth patterns among facial types.

INTRODUCTION: Extreme patterns of vertical facial divergence are of great importance to clinicians because of their association with dental malocclusion and functional problems of the orofacial complex. Understanding the growth patterns associated with vertical facial divergence is critical for clinicians to provide optimal treatment. This study evaluates and compares growth patterns from childhood to adulthood among 3 classifications of vertical facial divergence using longitudinal, lateral cephalograms from the Craniofacial Growth Consortium Study. METHODS: Participants (183 females, 188 males) were classified into 1 of 3 facial types on the basis of their adult mandibular plane angle (MPA): hyperdivergent (MPA >39°; n = 40), normodivergent (28° ≤ MPA ≤ 39°; n = 216), and hypodivergent (MPA <28°; n = 115). Each individual had 5 cephalograms between ages 6 and 20 years. A set of 36 cephalometric landmarks were digitized on each cephalogram. Landmark configurations were superimposed to align 5 homologous landmarks of the anterior cranial base and scaled to unit centroid size. Growth trajectories were calculated using multivariate regression for each facial type and sex combination. RESULTS: Divergent growth trajectories were identified among facial types, finding more similarities in normodivergent and hypodivergent growth patterns than either share with the hyperdivergent group. Through the use of geometric morphometric methods, new patterns of facial growth related to vertical facial divergence were identified. Hyperdivergent growth exhibits a downward rotation of the maxillomandibular complex relative to the anterior cranial base, in addition to the increased relative growth of the lower anterior face. Conversely, normodivergent and hypodivergent groups exhibit stable positioning of the maxilla relative to the anterior cranial base, with the forward rotation of the mandible. Furthermore, the hyperdivergent maxilla and mandible become relatively shorter and posteriorly positioned with age compared with the other groups. CONCLUSIONS: This study demonstrates how hyperdivergent growth, particularly restricted growth and positioning of the maxilla, results in a higher potential risk for Class II malocclusion. Future work will investigate growth patterns within each classification of facial divergence.

Comparison of the effect of cigarette smoke on mesenchymal stem cells and dental stem cells.

The persistent prevalence of cigarette smoking continues to contribute to preventable disease and death in the United States. Although much is known about the deleterious systemic effects of cigarette smoke and nicotine, some clinically relevant areas, such as the impact of cigarette smoke and nicotine on stem cells and the subsequent implications in regenerative medicine, still remain unclear. This review focuses on recent studies on the effect of cigarette smoke and one of its deleterious components, nicotine, on mesenchymal stem cells, with an emphasis on dental stem cells.

Unlocking ectopically erupting permanent first molars using light wires.

BACKGROUND AND OVERVIEW: Ectopic eruption of permanent molars is one of the challenges that arise in the early mixed dentition period, particularly when the root of the primary second molar is resorbed due to mesial angulation of the impacted first molar. The authors introduce a simple and efficient method to unlock ectopically erupting first molars using a light wire. CASE DESCRIPTION: The authors describe the cases of 2 girls (8 and 7 years old) who sought treatment for locking of their maxillary and mandibular first molars, respectively. A 0.012-inch nickel titanium wire was compressed and bonded to the first molars and primary second molars to unlock the first molars. The primary second molars were splinted to the adjacent primary first molars and canines using bonded multistranded wires. As the compressed wires straightened over time, the locked first molars were tipped back without any substantial mesial movement of the primary teeth. After unlocking the molars, the nickel titanium wires were removed to allow spontaneous eruption of the first molars. CONCLUSIONS AND PRACTICAL IMPLICATIONS: Although the primary molar roots were considerably resorbed, the ectopically erupting first molars were unlocked successfully without any substantial movement of the primary teeth. The clinical procedure was simple, and no laboratory procedures were needed. In addition, the anchorage burden was reduced with the use of light forces. The authors suggest that primary second molars with substantial root resorption due to ectopic eruption of permanent first molars can be saved simply and efficiently.