Cephalometric Measurements Research Articles

Analysis of upper airway measurements and cephalometric measurements using two-dimensional Cephalometry and threedimensional Computed Tomography in patients with skeletal Class III malocclusion.

Analysis of upper airway measurements and cephalometric measurements using two-dimensional Cephalometry and threedimensional Computed Tomography in patients with skeletal Class III malocclusion.

Effects of 3D Airway Geometry on the Airflow of Adults with Cleft Lip and Palate and Obstructive Sleep Apnea: A Functional Imaging Study.

Objective Individuals with cleft lip and palate (CLP) are at a high risk of developing obstructive sleep apnea (OSA). Hypothetically, the severity of OSA might be associated with the morphology of the upper airway (UAW) and the characteristics of the airflow. Thus, the present study aimed to assess and compare, in adults with CLP and skeletal class-III discrepancy, with or without OSA, simulations of airflow resistance and pressure according to the geometrical characteristics of the UAW and cephalometric parameters. Materials and Methods According to the results of type-I polysomnography tests, the sample ( n = 21) was allocated in 2 groups: 1) without OSA (N-OSA; n = 6); and 2) with OSA (OSA; n = 15). Cephalometric measurements were performed on the cone-beam computed tomography (CBCT) scans of the groups. After three-dimensional (3D) reconstructions, the volume (V) and minimal cross-sectional area (mCSA) of the UAW were generated. Computational fluid dynamics (CFD) simulations were used to assess key airflow characteristics. The results were presented at a significance level of 5%. Results The UAW pressure values and airway resistance did not differ between the groups, but there was a tendency for more negative pressures (26%) and greater resistance (19%) in the OSA group. Volume and mCSA showed a moderate negative correlation with resistance and pressure. The more inferior the hyoid bone, the more negative the pressures generated on the pharyngeal walls. Conclusion The position of the hyoid bone and the geometry of the UAW (V and mCSA) exerted effects on the airway-airflow resistance and pressure. However, key airflow characteristics did not differ among subjects with CLP, were they affected or not by OSA.

Lower Incisor-Pg: A New Cephalometric Parameter to Evaluate the Anterior Limit of Dentition.

Background: This present retrospective study aimed to introduce Lower Incisor-Pg and to assess how this new parameter varies with the skeletal sagittal and vertical relationships. Methods: A total of 1256 cephalometric analyses were performed using lateral cephalometric radiographs of a sample of subjects divided according to SN^Go-Gn, ANPg^, and IMPA measurements. The differences in Lower Incisor-Pg between the groups were assessed through ANOVA tests and posthoc analyses, while Pearson's correlation analysis was used to assess the correlations between the measurements. Results: The mesofacial growth pattern (61.0%) was more common than dolichofacial (30.0%) and brachyfacial (8.6%) ones in the sampled population. Regarding skeletal sagittal relationships, Class I was more frequent (70.9%) than Class II (19.3%) and Class III (9.8%). The mean value of the Lower Incisor-Pg was 3.2 ± 4.0 mm. Linear regression showed that the β coefficient was 0.45 and 0.36 for ANPg^ and SnGoGn^, respectively. Conclusions: Lower Incisor-Pg is a linear cephalometric measurement to evaluate the lower incisor sagittal position. For each degree of increase in ANPg^ and SNGoGn^, the Lower Incisor-Pg increased 0.45 mm and 0.36 mm, respectively.

Machine Learning Effectively Diagnoses Mandibular Deformity Using Three-Dimensional Landmarks

Jaw deformity diagnosis requires objective tests. Current methods, like cephalometry, have limitations. However, recent studies have shown that machine learning can diagnose jaw deformities in two dimensions. Therefore, we hypothesized that a multilayer perceptron (MLP) could accurately diagnose jaw deformities in three dimensions (3D). Examine the hypothesis by focusing on anomalous mandibular position. We aimed to: (1) create a machine learning model to diagnose mandibular retrognathism and prognathism; and (2) compare its performance with traditional cephalometric methods. An in-silico experiment on deidentified retrospective data. The study was conducted at the Houston Methodist Research Institute and Rensselaer Polytechnic Institute. Included were patient records with jaw deformities and preoperative 3D facial models. Patients with significant jaw asymmetry were excluded. The tests used to diagnose mandibular anteroposterior position are: (1) SNB angle; (2) facial angle; (3) mandibular unit length (MdUL); and (4) MLP model. The resultant diagnoses: normal, prognathic, or retrognathic. None. A senior surgeon labeled the patients' mandibles as prognathic, normal, or retrognathic, creating a gold standard. Scientists at Rensselaer Polytechnic Institute developed an MLP model to diagnose mandibular prognathism and retrognathism using the 3D coordinates of 50 landmarks. The performance of the MLP model was compared with three traditional cephalometric measurements: (1) SNB, (2) facial angle, and (3) MdUL. The primary metric used to assess the performance was diagnostic accuracy. McNemar's exact test tested the difference between traditional cephalometric measurement and MLP. Cohen's Kappa measured inter-rater agreement between each method and the gold standard. The sample included 101 patients. The diagnostic accuracy of SNB, facial angle, MdUL, and MLP were 74.3, 74.3, 75.3, and 85.2%, respectively. McNemar's test shows that our MLP performs significantly better than the SNB (P=.027), facial angle (P=.019), and MdUL (P=.031). The agreement between the traditional cephalometric measurements and the surgeon's diagnosis was fair. In contrast, the agreement between the MLP and the surgeon was moderate. The performance of the MLP is significantly better than that of the traditional cephalometric measurements.

Influence of BMI percentile on craniofacial morphology and development in adolescents,Part II: elevated BMI is associated with larger final facial dimensions.

Prevalence of adolescent obesity has markedly increased from 5.2% in 1974 to 19.7% in 2021. Understanding the impacts of obesity is important to orthodontists, as growth acceleration and greater pre-pubertal facial dimensions are seen in children with elevated body mass index (BMI). To identify whether adolescent obesity shifts the timing and rate of craniofacial growth resulting in larger post-treatment dimensions, we evaluated cephalometric outcomes in overweight/obese (BMI > 85%, n = 168) and normal weight (n = 158) adolescents (N = 326 total). Cephalometric measurements were obtained from pre- and post-treatment records to measure growth rates and final dimensions and were statistically evaluated with repeated measures analysis of variance and linear regression models. Overweight and obese adolescents began and finished treatment with significantly larger, bimaxillary prognathic craniofacial dimensions, with elevated mandibular length [articulare-gnathion (Ar-Gn)], maxillary length [condylion-anterior nasal spine (Co-ANS), posterior nasal spine-ANS (PNS-ANS)], and anterior lower face height (ANS-Me), suggesting overweight children grow more overall. However, there was no difference between weight cohorts in the amount of cephalometric change during treatment, and regression analyses demonstrated no correlation between change in growth during treatment and BMI. BMI percentile was a significant linear predictor (P < 0.05) for cephalometric post-treatment outcomes, including Ar-Gn, Co-ANS, ANS-Me, upper face height percentage (UFH:total FH, inverse relationship), lower face height percentage (LFH:total FH), sella-nasion-A-point (SNA), and SN-B-point (SNB). The study is retrospective. Growth begins earlier in overweight and obese adolescents and continues at a rate similar to normal-weight children during orthodontic treatment, resulting in larger final skeletal dimensions. Orthodontics could begin earlier in overweight patients to time care with growth, and clinicians can anticipate that overweight/obese patients will finish treatment with proportionally larger, bimaxillary-prognathic craniofacial dimensions.

The Correlation between Mandibular Arch Shape and Vertical Skeletal Pattern.

Background and Objectives: The aim of this study was to evaluate the correlation between the mandibular arch shape and the vertical skeletal pattern in growing patients. Materials and Methods: A total of 73 Caucasian patients (33 males and 40 females; mean age 9.4) were retrospectively enrolled from a pool of patients treated in chronological order at the Department of Orthodontics, University of Foggia, Italy, from April 2018 to December 2021. Each patient received a laterolateral radiograph and a digital scan of the dental arch. Eight cephalometric parameters (lower gonial angle, intermaxillary angle, divergence angle, Wits index, Jarabak ratio, OP-MP angle, PP-OP angle, and ANB) and five dental measurements (posterior mandibular arch width, anterior mandibular arch width, mandibular occlusal angle, posterior width on distobuccal molar cusps, and molar angle) were analyzed and then compared. A Spearman's rho correlation test between the cephalometric measurements and the dental measurements was performed. Statistical significance was set at p < 0.05. Results: A negative statistically significant correlation was found between the Jarabak ratio and the intermolar angle; a statistically significant correlation was also observed between the Wits index, the posterior mandibular width, and the occlusal mandibular angle; the ANB angle and the occlusal mandibular angle; the intermaxillary angle (PP-PM) and the mandibular occlusal angle, posterior mandibular width on the disto-vestibular cusp, and the intermolar angle; and the OP-MP angle and mandibular occlusal angle and the posterior mandibular width on the disto-vestibular cusp. Conclusions: The mandibular arch form may be related to certain predisposing features in craniofacial morphology, such as jaw divergence, the Jarabak ratio, and the intermaxillary angle.

Comparison of angular measurements in cephalometrics and photographs.

Abstract:&#x0D; Introduction: The evaluation of the facial profile is an important factor in any current orthodontic diagnosis and accurate treatment planning is dependent on it.&#x0D; Aims and Objectives: The aim and objective of the study is to find out differences in angular measurements between photographic and cephalometric measurements whether photographic measurements can be used in place of cephalometric measurements.&#x0D; Material &amp; Methods: The study comprised 100 volunteers (50 males and 50 females) ranging in age from 12 to 16 years. The respondents were chosen at random throughout the sampling process. Cephalometric and photographic profile analysis was used, with angular measurements based on standard cephalometric and photographic records taken in natural head position in lateral view. Lateral cephalogram was used for cephalometric analysis and photograph taken in lateral view was used for evaluation. The study included four factors in total.&#x0D; Results: There was no significant difference in facial angular measurements between the cephalometric and photographic analysis.&#x0D; Conclusion: This study concluded that photographic measurements can be used in place of lateral cephalogram as there are negligible differences between them&#x0D; Keywords: Photographic analysis, Cephalometric analysis, Naso-labial angle, Naso-mental angle, Naso-frontal angle, Naso-facial angle

Cephalometric analysis performance discrepancy between orthodontists and an artificial intelligence model using lateral cephalometric radiographs.

The purpose of the present clinical study was to compare the Ricketts and Steiner cephalometric analysis obtained by two experienced orthodontists and artificial intelligence (AI)-based software program and measure the orthodontist variability. A total of 50 lateral cephalometric radiographs from 50 patients were obtained. Two groups were created depending on the operator performing the cephalometric analysis: orthodontists (Orthod group) and an AI software program (AI group). In the Orthod group, two independent experienced orthodontists performed the measurements by performing a manual identification of the cephalometric landmarks and a software program (NemoCeph; Nemotec) to calculate the measurements. In the AI group, an AI software program (CephX; ORCA Dental AI) was selected for both the automatic landmark identification and cephalometric measurements. The Ricketts and Steiner cephalometric analyses were assessed in both groups including a total of 24 measurements. The Shapiro-Wilk test showed that the data was normally distributed. The t-test was used to analyze the data (α = 0.05). The t-test analysis showed significant measurement discrepancies between the Orthod and AI group in seven of the 24 cephalometric parameters tested, namely the corpus length (p = 0.003), mandibular arc (p < 0.001), lower face height (p = 0.005), overjet (p = 0.019), and overbite (p = 0.022) in the Ricketts cephalometric analysis and occlusal to SN (p = 0.002) and GoGn-SN (p < 0.001) in the Steiner cephalometric analysis. The intraclass correlation coefficient (ICC) between both orthodontists of the Orthod group for each cephalometric measurement was calculated. Significant discrepancies were found in seven of the 24 cephalometric measurements tested between the orthodontists and the AI-based program assessed. The intra-operator reliability analysis showed reproducible measurements between both orthodontists, except for the corpus length measurement. The artificial intelligence software program tested has the potential to automatically obtain cephalometric analysis using lateral cephalometric radiographs; however, additional studies are needed to further evaluate the accuracy of this AI-based system.

Cephalometric Prediction of Risk Factors for Mandibular Third Molar Impaction

Background: Mandibular third molar impaction in adult patients is one of the most common problems in dental practice. However, limited data are available on the association between mandibular third molar impaction and craniofacial skeletal problems. Aim: This study aimed to establish a prediction model to evaluate the risk factors for mandibular third molar impaction. Methods: Panoramic and lateral cephalometric radiographs of orthodontic patients aged ≥20 years were obtained from the Tri-Service General Hospital. The radiographs were analyzed by a single examiner. Panoramic radiographs were used to evaluate the mandibular third molar impaction. Lateral cephalometric radiographs were used to evaluate five linear and six angular measurements to define the facial pattern of the participants. The association between cephalometric measurements and mandibular third molar impaction was determined using one-way analysis of variance and logistic regression analysis. Results: This study included 60 participants. The incidence of mandibular third molar impaction was associated with the mandibular plane angle (MPA) and mandibular length (Co-Gn) (P &lt; 0.001). The presence of mandibular third molar impaction was found to gradually increase with increasing MPA and decreasing mandibular length. Conclusion: Individuals with a greater MPA and lesser mandibular length had a higher incidence of mandibular third molar impaction.

Skeletal Pattern of Bangladeshi Patients with Class II Malocclusion Attending in a Selected Private Setting

Background: The term "Class II malocclusion" encompasses a range of dental and skeletal characteristics, making precise diagnosis and treatment planning challenging. This study aimed to examine 32 Bangladeshi patients with Class II malocclusion to evaluate maxillary and mandibular skeletal positions using cephalometric measurements commonly used in clinical practice. Methods: Study casts and lateral cephalograms of 32 patients (17 females and 15 males) with Class II malocclusion were analyzed. Inclusion criteria comprised Class II molar relationship, the absence of craniofacial deformities, and no previous orthodontic treatment. Cephalometric measurements included SNA, SNB, and ANB angles, and data were analyzed using SPSS software. Results: Among the patients, 53% exhibited maxillary skeletal protrusion, 43% had mandibular retrusion, and only 3.1% presented both maxillary protrusion and mandibular retrusion. Surprisingly, 31.2% showed maxillary skeletal retrusion, and 28.1% exhibited mandibular protrusion, highlighting the significant variation in skeletal patterns within this cohort. Conclusion: Our findings emphasize the diverse skeletal patterns present among Bangladeshi patients with Class II malocclusion. The implications of these variations for treatment planning are substantial, as the treatment approach may differ depending on the underlying skeletal pattern. Given this diversity, individualized assessment and tailored treatment strategies are essential to achieve optimal outcomes. While this study has provided valuable insights, future research with larger and more diverse samples is warranted to further explore these complex relationships. Update Dent. Coll. j: 2023; 13(2): 34-37

Cephalometric profile analysis between genders. A study protocol

Background: According to current American Association of Orthodontists guidelines, two-dimensional lateral and posteroanterior cephalometric radiographs are recognized as essential components of diagnostic imaging records in orthodontics. Cephalometry is defined as the discipline that analyzes the craniofacial complex in a segmented way, to study the interrelationships between its structures and understand how the growth or alteration of one of these structures can compromise the whole. Through cephalometry, it is possible to indicate the clinical approach for patients, involving dental therapy with intraoral appliances and physical therapy with continuous positive pressure in the upper airway. Objectives: Investigate possible differences in cephalometric anatomical patterns between genders. Methods: This study protocol follows the STROBE - Strengthening the Reporting of Observational Studies in Epidemiology guidelines. A convenience sample will be used, consisting of teleradiography (cephalograms) of adult patients of both genders, carried out in a private Dental Clinic, located in the city of São José dos Campos (SP), Brazil, by the established inclusion and exclusion criteria. Six angular and nine linear measurements will be used in the analysis of cephalometric measures according to the study protocol. The exams will be distributed into three groups and paired according to the value of the angle formed between point A nasion and point B nasion (ANB). Groups will be formed by exams with class 1 skeletal relationship (0o &lt; ANB angle ≤ 4º), group 2 with class 2 exams (ANB angle &gt; 4°), and group 3 formed by class 3 exams (ANB angle ≤ 0°). Considerations: In some cases, craniofacial changes may predict the risk of sleep-disordered breathing, such as obstructive sleep apnea (OSA). Increased length and thickness of the soft palate and hyoid bone in the mandibular plane and retrognathia are associated with the pathogenesis of OSA. Therefore, the etiology of sleep-disordered breathing may vary in patients according to gender, according to cephalometric analysis.

Malocclusion in cats associated with mandibular soft tissue trauma: a retrospective case-control study.

The aim of this study was to determine whether an association existed between cephalometric measurements, maxillomandibular dental arch distances and the occurrence of traumatic malocclusions in the mandibular soft tissues of cats. Cats that had presented for dental consultations and that underwent cone-beam CT during diagnostic assessment were included in the study and categorised as cases and controls in a 1:2 ratio. Cases were designated as cats with a clinical diagnosis of malocclusion causing trauma to the buccal mandibular soft tissues or pyogenic granuloma secondary to the trauma, and controls were designated as cats with the absence of such diagnoses and without a history of other musculoskeletal anomalies in the head. Cephalometric measurements, including skull and facial indexes, as well as distances and angulations between dental crowns and crown tips, were calculated and analysed statistically. In total, 72 cats (24 cases and 48 controls) were included in the study. Cephalometric measurements revealed a significant association between the skull and facial indexes and the occurrence of traumatic malocclusions in the caudal teeth. Brachycephaly was a strong predictor of the occurrence of traumatic malocclusions. In addition, the space between crown tips and teeth angulations was a contributing factor to the trauma. Cats with traumatic malocclusions in the cheek teeth tend to present a narrower interdental space between the maxillary and mandibular carnassial teeth, mostly attributed to skeletal and dental malocclusion. These findings can be used to help raise awareness about this disease in cats and its association with brachycephaly. Cut-off values have been proposed and could be used in the selection of cats by breeders to reduce the occurrence of this disease.

Facial recognition by cloud-based APIs following surgically assisted rapid maxillary expansion.

This study aimed to investigate whether the facial soft tissue changes of individuals who had undergone surgically assisted rapid maxillary expansion (SARME) would be detected by three different well-known facial biometric recognition applications. To calculate similarity scores, the pre- and postsurgical photographs of 22patients who had undergone SARME treatment were examined using three prominent cloud computing-based facial recognition application programming interfaces (APIs): AWS Rekognition (Amazon Web Services, Seattle, WA, USA), Microsoft Azure Cognitive (Microsoft, Redmond, WA, USA), and Face++ (Megvii, Beijing, China). The pre- and post-SARME photographs of the patients (relaxed, smiling, profile, and semiprofile) were used to calculate similarity scores using the APIs. Friedman's two-way analysis of variance and the Wilcoxon signed-rank test were used to compare the similarity scores obtained from the photographs of the different aspects of the face before and after surgery using the different programs. The relationship between measurements on lateral and posteroanterior cephalograms and the similarity scores was evaluated using the Spearman rank correlation. The similarity scores were found to be lower with the Face++ program. When looking at the photo types, it was observed that the similarity scores were higher in the smiling photos. Astatistically significant difference in the similarity scores (P < 0.05) was found between the relaxed and smiling photographs using the different programs. The correlation between the cephalometric and posteroanterior measurements and the similarity scores was not significant (P > 0.05). SARME treatment caused asignificant change in the similarity scores calculated with the help of three different facial recognition programs. The highest similarity scores were found in the smiling photographs, whereas the lowest scores were found in the profile photographs.

Comparing Facial Esthetic and Volumetric Changes of an Edentulous Patient After Either Conventional or Neutral Zone Technique

The aim of the present case report was to compare the soft tissue measurements, volumetric differences on face of the patient whose complete dentures were fabricated either with conventional or neutral zone impression techniques. Two different complete dentures were fabricated according to conventional and neutral zone impression techniques. The measurement of soft tissue changes was evaluated on lateral cephalograms; conventional technique (L1), neutral zone technique (L2) and with no dentures (L3). Three images (I) were taken on the same day respectively with dentures completed by conventional technique (I1), dentures completed by neutral zone technique (I2), and with no dentures (I3). Superimposition of the images were evaluated. The cephalometric soft tissue measurements of the present case showed that upper and lower lips were positioned anteriorly in both conventional (L1) and neutral zone techniques (L2) on sagittal plane. These results could be attributed to the fact that the placement of the prosthesis in mouth helps directing lip position with big linear measurements. Volumetric difference between conventional (I1) and no denture (I3) images was more pronounced compared to neutral zone (I2) superposition with no denture (I3).

Comparison of Computed Tomography Assisted 3D Cephalometric Measurements in Straight Egyptian Arabian and Thoroughbred Horses.

Dental malocclusions are commonly encountered in horses. The objective of this study was to report the normal cephalometric values from skull computed tomography (CT) scans of adult Straight Egyptian Arabian (SEAR) and thoroughbred (TB) horses and to compare differences in the measurements between the two breeds. Standing skull CTs were performed on 29 clinically normal adult horses (15 SEAR; 14 TB) and cephalometric measurements were taken. All 9 cephalometric measurements, as well as the interincisal angle, were found to be significantly greater in TB than SEAR (P < 0.05). TB were found to have significantly greater facial line: mandibular length (FL/ML) ratios compared to SEAR (P = 0.002) whereas for the maxillary cheek teeth length: ethmoidal line ratio (Mxa/EtL), SEAR were found to have significantly greater values than TB (P = 0.0007). SEAR cephalometric measurements, as well as certain ratios, differ significantly from TB and could have an impact on the development of dental malocclusions in this breed. Further investigation is needed to ascertain whether these cephalometric differences between the two breeds predispose the SEAR to the development of dental malocclusions.

Self-Reported Olfactory Outcomes in Transplanum and Transtuberculum Approaches.

Objectives The aim of this study was to determine the clinical characteristics and cephalometric risk factors associated with decreased postoperative olfaction in patients in whom the transplanum and transtuberculum expanded endonasal approach (EEA) was performed. Methods A retrospective cohort of 41 patients treated with the transplanum and transtuberculum EEA was divided into two groups based on the maximum change in the postoperative 22-item Sino-Nasal Outcome Test (SNOT22) olfaction score: prolonged olfactory loss group ( n = 5) with a ΔSNOT22 olfaction score of ≥ 4 without a return to baseline and a preserved olfaction group ( n = 36) with a ΔSNOT22 olfaction score ≤ 3 with return to baseline on follow-up of at least 3 months. Demographics, operative details, and cephalometric measurements were compared between the two groups. Results There were no differences in terms of the type of surgical approach (transplanum and transtuberculum), resection of turbinates (middle and superior), use of reconstructive flap (nasoseptal flap and reverse flap), or tumor pathology between the two groups. In the prolonged olfactory loss group, there was a smaller angle between the planum and the face of the sella (89.75 ± 9.18 vs. 107.17 ± 16.57 degrees, p = 0.05) and a smaller angle between the anterior nasal spine and the sphenoid sinus face (21.20 ± 2.49 vs. 25.89 ± 4.90 degrees, p = 0.047) compared with the preserved olfaction group. Conclusion Patients with a narrow angle between the planum and the face of the sella or that between the anterior nasal spine and the sphenoid sinus face are at a higher risk of prolonged olfactory dysfunction with the transplanum and transtuberculum approaches. Level of Evidence IV.

Skeletal and Dentoalveolar Effects of Maxillary Protraction Using Tooth- and Miniscrew-Anchored Devices in Patients with Class III Malocclusion with Maxillary Deficiency: A Retrospective Follow-Up Study

Introduction: This retrospective study aimed to determine skeletal and dental changes after a growth spurt and shortly after treatment using a facemask in skeletal Class III malocclusion with maxillary deficiency. Methods: We retrospectively studied 50 patients (25 patients per group) with skeletal Class III malocclusion who underwent facemask treatment with tooth-anchored (T-A, mean age 7.92) and miniscrew-anchored (M-A, mean age 9.84) intraoral appliances. In both groups, the facemask applied a traction force of 350–400 g to each side, such that the traction was directed 30° forward and downward. Lateral cephalometric radiographs were obtained from all patients before (T1), immediately after (T2), and at an average of 37.11 months after maxillary protraction (T3). A total of 13 cephalometric measurements were analyzed to determine the skeletal and dental changes. A paired t-test was used to verify the effects before, after, and during follow-up periods in each group. Results: An anteroposterior relationship, the values of SNA and ANB, evident in both groups at T2, was significantly improved in the M-A group (p &lt; 0.05). However, the values of ANB and MP–SN, which indicate the relapse of anteroposterior and vertical relation of maxilla and mandible, were significantly higher in the T-A group compared with the M-A group during follow-up period. The maxillary first molars were significantly more extruded and maxillary incisors were more protruded in the T-A group than the M-A group, and this persisted at T3 (p &lt; 0.05). Conclusions: Miniscrew-anchored maxillary protraction increased the skeletal improvement of anteroposterior relationship and reduced the dental and skeletal relapses compared with tooth-anchored maxillary protraction in growing patients with a hyperdivergent patterns and skeletal Class III malocclusion.

Evaluation of effectiveness and efficiency of fixed orthodontic treatment comparing standard and computer-aided design and manufacturing conventional bracket systems using indirect bonding for both: A retrospective study

To compare the effectiveness and efficiency of orthodontic treatment (OT) with standard versus computer-aided design and computer-aided manufacturing (CAD/CAM) indirect bonding of conventional brackets. This retrospective study examined two groups: standard indirect bonding group (12 males, 13 females; mean age 12.21 ± 0.52 years), and digital indirect bonding group (11 males, 14 females; mean age 12.76 ± 1.32 years), treated via a CAD/CAM indirect bonding system. Conventional brackets were used in both groups. Pretreatment and post-treatment records were acquired for all subjects. Weighted Peer Assessment Rating (W-PAR) index was used to assess the effectiveness of OT, in conjunction with five angular cephalometric measurements (ANB°, Sn-GoGn°, U1-PP°, IMPA° and FMA°) and comparatively analyzed using generalized mixed-effects models and post hoc test. Treatment efficiency was assessed in terms of the numbers of bracket repositionings, archwire bends, accidental bracket debondings, appointments and treatment months. Comparative analysis of efficiency was performed using the asymptotic Wilcoxon-Mann-Witney test. Statistical significance was set at 5%. Total W-PAR and W-PAR component scores decreased significantly during treatment for both groups and in a similar way. Cephalometric measures ANB° and IMPA° significantly decreased and increased, respectively. Significantly fewer bracket repositionings, number of appointments and treatment months were recorded in group digital indirect bonding. Although both methods investigated were effective to achieve good outcomes, CAD/CAM indirect bonding method increased the efficiency of OT, when conventional brackets are used.

Revealing the representative facial traits of different sagittal skeletal types: decipher what artificial intelligence can see by Grad-CAM

ObjectivesAesthetic improvement is a significant concern in dental therapy. While orthodontic treatment primarily targets hard tissue, the impact on soft tissue and the extent of these changes remains empirical. This study aims to unveil the intricate relationship between facial soft tissue and skeletal types using artificial intelligence (AI) analysis. MethodsFirst, we collected a dataset of 1044 3-side-photographs and categorized them based on cephalometric measurements. After pre-processing and data augmentation, samples were fed to two independent models (Sfa, Res model) for training and testing. After validating that the Sfa model could accurately recognize the skeletal types based merely on photographs, Grad-CAM algorithm was utilized for model decipherment. Verification of the vital traits were carried out by facial adjustment simulation. ResultsThe Sfa model demonstrated superior accuracy (0.9293) in identifying skeletal types based solely on soft tissue, compared to the Res model (0.8395) and even trained orthodontists (0.764), testifying our hypothesis that AI could be more capable of processing imperceptible cues compared to mankind. Intriguingly, Grad-CAM revealed that cheek volume, forehead, chin and nasolabial traits could be representative features of each type, exceeding the traditional knowledge which merely concerns mandible and chin. ConclusionBy constructing a deep learning model as a classifier and then decipher it with Grad-CAM, we revealed the subtle and unnoticed cues associating skeletal and soft tissue, as well as provided a novel approach that could aid practitioners in devising tailored treatment plans for enhanced esthetic outcomes. Clinical significanceThe proposed AI methods offer valuable assistance to practitioners in identifying uncoordinated facial traits that may detract from a patient's attractiveness. By incorporating these insights into customized treatment plans, dental therapy can maximize esthetic benefits for individual patient.

Artificial intelligence web-based cephalometric analysis platform: comparison with the computer assisted cephalometric method

ABSTRACT Purpose The aim of this investigation was to evaluate the reliability and accuracy of cephalometric measurements of the web-based artificial intelligence cephalometric analysis platform in comparison with the computer assisted cephalometric analysis method. Materials and Methods 60 patients’ pretreatment lateral cephalograms were randomly selected. A total of 21 landmarks were identified by one operator and a total of 20 parameters were measured both AI based platform WebCeph® and Dolphin Imaging®. Measurements of AI landmarking were recorded. Then, the landmarks placed automatically by the AI (AI landmarking) were corrected manually (manual landmarking). All the measurements were recorded and performed once more after 4-weeks. Correlation between repeated measurements was evaluated by using the Pearson correlation coefficient. Paired t-test was used for comparisons between groups. Results Most of the measurements showed statistically significant differences between AI landmarking and manual landmarking 1, except for the angular measurements of the U1-SNº (P = 0.717), interinsizal angle (P = 0.410), and L1-NBº (P = 0,295). Most of the measurements were found to be statistically similar between manual landmarking 1 and manual landmarking 2, except for the angular measurement of the SN-GoGnº, IMPAº, linear measurements ANS-Me. The Pearson correlation coefficients of all cephalometric measurements were above 0.80. Conclusions All mean differences between the manual landmarking 1 and AI landmarking measurements were less than 2 degrees/2 mm, except for the nasolabial angle. Although WebCeph’s artificial intelligence algorithm is not sufficient to accurately determine the position of soft tissue landmarks, it becomes more suitable for clinical use with the control and manual correction of landmarks by observers.