Objectives: This study aimed to examine the outcome and stability of the anterior open bite treatment with clear aligners. Methods: Fifty-two adult anterior open bite patients who underwent nonextraction clear aligner treatment were enrolled. All cases were retained with upper and lower fixed and vacuum-formed retainers. Eleven cephalometric measurements at pretreatment (T1), end-of-active-treatment (T2), and at least 1-year post-treatment (T3) were evaluated. The changes during the treatment and retention period were calculated. Results: Mean end-of-treatment (T2) overbite was 1.1 ± 0.7 mm. The mean change in overbite during treatment was 3.3 ± 1.5 mm. Mean retention (T3) overbite was 1.3 ± 0.9 mm, with a mean increase in overbite of 0.2 ± 0.5 mm (P = 0.59) during the retention period. None of the eleven cephalometric measurements showed significant change during the retention period. Conclusions: Anterior open bite was successfully corrected in all the patients (n = 52) with clear aligners. When retained with upper and lower fixed retainers and upper and lower vacuum-formed retainers, there was no significant change in cephalometric measurements during retention period. Treatment stability could not be predicted using cephalometric measurements at pre-treatment, the change of cephalometric variables during treatment, retention time, or previous orthodontic treatment.

Introduction: This study was designed to analyze the cephalometric changes in adult Class III malocclusion treated with clear aligner therapy. Methods: In this retrospective study, thirty-six Class III adult patients treated with clear aligner therapy in private practice and a graduate orthodontic clinic were included in this study. Inclusion criteria included patients aged 18 years and older, Class III molar relationship that is end-on or greater, at least one anterior tooth that is in crossbite or incisors in an edge-to-edge bite, and complete records (initial and final lateral cephalograms) that are clear and traceable. Twenty-two cephalometric measurements were measured and analyzed by two calibrated judges. Results were categorized by skeletal vertical, skeletal anterior-posterior, dental vertical, and dental anterior-posterior. Descriptive analysis for mean, standard deviation, range, and percent was completed for demographic information, a paired T test to determine pretreatment and posttreatment cephalometric differences was performed, and a chi-square test for proportions was conducted. Results: No vertical changes were noted in upper and lower molar positions, and the upper incisor inclinations were maintained. On the other hand, lower incisors retroclined on average 5.6 degrees and retracted 1.78 mm. There was no change in the mandibular plane angle across different vertical pattern groups (normodivergent/hypodivergent/hyperdivergent patients). The only cephalometric variable that was statistically significant between different vertical pattern growers was the overbite. Conclusions: Adult patients with Class III malocclusion treated with clear aligners have good vertical control with no increase in mandibular plane angle and anterior face height. Clear aligner therapy is also good at maintaining vertical control for hyperdivergent patients. Finally, adult Class III dental camouflage treatment was resolved primarily through maintaining upper incisor inclination and lower incisor retroclination.

Introduction: Non-syndromic cleft lip with or without cleft palate (NCL±P) is characterized by a multifactorial etiology with both genetic and environmental factors playing a role in its embryonic development. Recent genetic studies have identified susceptibility loci and genetic variations in several genes that were associated with the risk of developing NCL±P. The purpose of this study was to investigate the association of MSX1, BMP4, TGFβ3, and GSK3β gene variants with NCL±P in a casecontrol data set from Karaikal, India. Methods: The case sample consisted of 331 individuals who were diagnosed with CL (bi/unilateral cleft lip), CLP (bi/unilateral cleft lip and palate), or CP (cleft palate). The control sample consisted of 156 individuals from the same location who were not affected with an orofacial cleft and had a negative family history of NCL±P. Genotype proportions and allele frequencies were determined and compared. Results: We tested differences in proportions of genotypes and allele frequencies in four gene variants. No statistically significant differences were found in single nucleotide polymorphisms (SNPs) of MSX1 rs3821949 and BMP4 rs17563. However, when comparing frequencies of TGFβ3 alleles in bilateral NCL±P cases vs controls, there was a close-to-significant difference at p = 0.069165 found. When frequencies of GSK3β alleles in female NCL±P cases vs female controls were compared, the difference was marginally statistically significant at p = 0.058246. Conclusions: Out of four SNPs studied in this Indian population, a possible association with NCL±P was found for GSK-3β rs13314595 and for TGFβ3 rs3917201. It was previously observed that variants of susceptibility genes may occur only in some cleft populations. Therefore, it is important to perform genetic studies in local populations. Knowledge of the presence of certain SNPs is essential if risk calculations or prevention measures are considered.

Background and purpose: In recent years, questions regarding the genetic and environmental factors affecting variation in human craniofacial morphology have received increasing attention. Medical and clinical genetic research using family studies has proven foundational for our understanding of which genes affect craniofacial variation. On the other hand, cephalometricbased studies showed a relationship between the cranial base and midface characteristics among individuals with different skeletal pattern of malocclusion. The purpose of our pilot study was to analyze specific variants of facial genes that were suggested to be associated with cranial base width and depth in Class II and Class I malocclusions. Methods: Patient data (extraoral photographs, intraoral photographs, and iCAT CBCT images obtained as part of patients’ routine orthodontic examinations) was collected for patients who had come to the Orthodontic Clinic, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, CA, from July 2019 to July 2021. For 72 patients who met the inclusion criteria for Class I or Class II groups in our study, saliva samples were collected, and DNA was isolated and analyzed using rtPCR genotyping for the following single-nucleotide gene polymorphisms (SNPs): rs79272428 (A>G), rs17106852 (A>G), rs12786942 (A>T) and rs6555969 (C>T). Results: We observed differences between Class I and Class II malocclusions in genotype proportions and allele frequencies in gene variants rs6555969 (C>T) and rs12786942. Genotype 4 CT (rs6555969) was found in a higher frequency in the Class I group generally and in the phenotypic Cluster 1. There were no differences observed for other gene variants studied. Regarding the cranial base characteristics, Asian patients had shorter and more acute cranial base. In Hispanic patients, there was a significant difference (P<0.005) between Class I and Class II patients regarding the cranial base width. Conclusions: The aim of our study was to determine genotypic differences between Class I and Class II malocclusion groups and to study genotypic associations with phenotypic clusters. We showed genotypic and phenotypic cluster differences between Class I and Class II groups. These differences were not statistically significant, probably, due to a small size of the studied groups. However, in this pilot study, we found trends, on which we will focus in our future study using a larger sample.

Background and Purpose. Orthodontic treatment helps to ensure proper function of teeth and to create healthy smiles. To this aim, the orthodontist’s goal is establishment of an esthetic harmony between soft and hard tissues of the face. Dimensions of facial width and height are crucial for accurate diagnosis and formulation of an efficient treatment plan. A knowledge of genetic determinants of these dimensions in Class II patients will deepen our understanding of etiology of skeletal Class II malocclusions and would make it possible to personalize a patient’s treatment plan. The purpose of our pilot study was to analyze, if specific variants of PAX 3, PAX 5, PAX 7 and PAX 9 genes are associated with Class II malocclusion but not with Class I malocclusion or vice versa. Methods. Patient data (extraoral photographs, intraoral photographs, and iCAT CBCT images obtained as part of patients’ routine orthodontic examinations) was collected for patients who had come to the Orthodontic Clinic, Arthur A. Dugoni School of Dentistry, University of the Pacific, San Francisco, CA, from July 2019 to July 2021. For 72 patients who met the inclusion criteria for Class I or Class II groups in our study, saliva samples were collected, and DNA was isolated and analyzed using rtPCR genotyping for PAX 3 SNP: rs974448, PAX 5 SNP: rs7031673, PAX 7 SNP: rs4920520 and PAX 9 SNP: rs8004560. 4 Results. Genotype A5G5 (rs7031673, PAX5) was high in Class I generally, but also in phenotypic Cluster 1 and Cluster 9. Genotype G5G5 (rs7031673, PAX5) was high in Class II generally, but also in phenotypic Cluster 8 and Cluster 10. Allele G5 was more frequent in Class II than in Class I. Genotype A7A7 (rs4920520, PAX7) was high in Class II generally. It was absent in phenotypic Cluster 1 and Cluster 9, present in phenotypic Cluster 8 and Cluster 10. Genotype A9G9 (rs8004560, PAX9) was higher in Cluster 8 than in Cluster 10 (and also higher than in Clusters 1 and 9). Allele A9 was more frequent in Class II than in Class I. Conclusions. The aim of this study was to determine genotypic differences between Class I and Class II malocclusion groups and to study genotypic associations with phenotypic clusters. We showed genotypic and phenotypic cluster differences between Class I and Class II groups. We report several genotypes tentatively identified by genotypic analysis and found in association with certain phenotypic clusters. None of these differences proved to be statistically significant, probably, due to a small size of the studied groups. However, in this pilot study, we found trends, on which we will focus in our future study using a larger sample.

OBJECTIVES. Determining optimal magnitude as well as duration of force is important for clinicians because the magnitude of tooth root movement is positively correlated with the magnitude of applied orthodontic force. Biomarkers of orthodontic tooth movement in gingival crevicular fluid (GCF) could be utilized to determine how specific patient’s periodontal tissues react to the applied force. A quantitative relationship between the magnitude of force applied to a tooth and the amount of GCF biomarker should be determined. METHODS. Periodontal response to applied force was quantified by GCF flow measurements. In two participants, GCF was collected from ten maxillary teeth and ten mandibular teeth at baseline, initially and finally on each of six sequential aligners. Measured volumes were compared to sham aligners that applied no force. GCF was collected using Periostrips (Oraflow) and volume was measured by Periotron 8000 (Oraflow) (IRB#2021-61). Actual tooth movements were measured as crown movements on iTero digital models. RESULTS. We calculated the aligner ratio as sum of end GCF volume values on aligners divided by sum of initial GCF volume values on aligners applied to a tooth. Comparison of iTero-measured 3D distances with aligner ratios suggested a positive correlation relationship on maxillary teeth. Aligner ratio value less or equal 1 may indicate that a weekly period of aligner wear was sufficient. Aligner ratio value higher than one may indicate that a week period of aligner wear was too short, showed by increased GCF flow on the end of aligner wear. CONCLUSIONS. Simple measurements of GCF flow and iTero-measured distances may give us information about the relationship between patient’s capability to have teeth moved and frequency of Invisalign aligners

Objectives: Analyze skeletal changes and condylar resorption, remodeling, and positional changes in patients with Surgery First Approach (SFA) during orthodontics with fixed braces or aligner therapy. Methods: This retrospective longitudinal study, approved by the University of the Pacific IRB (#2021-70), compared skeletal changes between fixed orthodontics and Invisalign® therapy in patients undergoing the surgery-first approach (SFA). The study included 46 patients (28 fixed, 18 Invisalign). Cone-beam computed tomography (CBCT) scans were obtained at three timepoints: pre-surgery (T1), post-surgery (T2), and after orthodontic treatment (T3). Using InViVo 3- Dimensional Software, AI-based landmark identification, and standardized reference planes were employed for dental and skeletal measurements. Regional registration at the condylar level was also performed using 3D Slicer. Custom analyses were performed to assess anterior-posterior, vertical, and transverse changes. Statistical analysis included Spherical Harmonics (SPHARM) mesh statistics to assess condylar shape changes. Student's t-test and Mann-Whitney tests were used to compare the results between the groups and Spearman correlations. Results: Both groups presented similar skeletal movements during surgery (T2-T1). Frankfort Mandibular Plane (MP-FH) increased in the fixed group while decreased in the Invisalign group when comparing T3-T2. No significant dental changes were observed between the two groups. Mandibular body length (Gonion to Pogonion) decreased more in the fixed group. There were no significant condylar positional changes between the two groups (T2-T1) and no differences in remodeling (T3-T2). Conclusion: Most skeletal variables did not show statistically significant differences between the two groups, and the condylar changes were also similar when comparing T2-T1 and T3-T2. This study’s findings suggest that both techniques are safe and provide similar skeletal, dental, and condylar outcomes.

Objectives: This study aimed to compare the skeletal and dental changes, efficiency, and side effects of Class II correction in growing patients using clear aligners with Class II elastics compared to mandibular advancement (MA). Materials and Methods: A total of 66 growing Class II patients were included in this study. 20 patients were treated with Class II elastics, 25 patients were treated with MA, and 21 subjects were untreated Class II subjects. 9 cephalometric measurements and 3 study cast measurements were evaluated at initial (T1) and end of treatment (T2). Results: No significant differences were shown at T2 between the elastic and MA groups, indicating similar treatment outcomes for all variables. Final molar relationship and overjet for the control group demonstrated a Class II relationship while the elastic and MA groups corrected to a Class I relationship. Skeletal changes from T1 to T2 in the MA group, with reduction in SNA (-1.09°) and ANB (-1.69°), demonstrated a “headgear effect” in addition to dentoalveolar Class II correction. However, the elastics group demonstrated solely dentoalveolar correction. Linear regression revealed significant lower incisor proclination of 5.28° as a result of treatment with Class II elastics while lower incisor proclination was maintained with MA treatment. Conclusions: Clear aligner treatments with Class II elastics and MA are effective at correcting Class II malocclusions in growing patients that would have otherwise been maintained without intervention. Class II correction occurred primarily through dentoalveolar changes, although there was a skeletal component with MA treatment.

Introduction: To develop facial growth prediction models using artificial intelligence (AI) under various conditions, and to compare the performance of these models with each other as well as with the partial least squares (PLS) growth prediction model. Materials and Methods: Longitudinal lateral cephalograms from 33 subjects in the Mathews growth collection were utilized. The dataset included 1,257 pairs of before and after growth lateral cephalograms. In each image, 46 hard and 32 soft tissue landmarks were manually identified. Growth prediction models were constructed using both a deep learning method based on the TabNet deep neural network and PLS method. The prediction accuracies of the two methods were compared. Results: On average, AI showed 0.61 mm less prediction error than PLS. Among the 77 predicted landmarks, AI was more accurate than PLS in 60 landmarks. When comparing AI models with varying numbers of training epochs, those with higher epochs yielded more accurate predictions. Overall, both PLS and AI methods exhibited greater prediction errors for soft tissue and mandibular landmarks compared to hard tissue and maxillary landmarks. However, the AI method showed a smaller increase in prediction error in areas with greater variability. Conclusions: AI proved to be a valuable growth prediction method, with clinically acceptable prediction errors averaging 1.49 mm for 45 hard tissue landmarks and 1.71 mm for 32 soft tissue landmarks. PLS accurately predicted landmarks with low variability. However, AI generally outperformed PLS, particularly for landmarks in the lower part of the craniofacial structure and soft tissue, where uncertainty is considerable.

Introduction: Orofacial clefts, including non-syndromic cleft lip and cleft palate (NCLP), are among the most common congenital anomalies affecting approximately 1 in 700 live births. The etiology of NCLP is multifactorial involving both genetic and environmental factors. MTHFR 677CT polymorphism belongs to a group of candidate genes. Deficiency of folate belongs to environmental factors contributing to etiology of NCLP. Folate plays a critical role in DNA synthesis and cellular methylations. It was feasible to investigate them together in human dental stem cells (hDSC). hDSC are derived from neural crest cells that are integral to craniofacial development. This study investigates the effects of folate on hDSC exposed to ischemia/reperfusion injury. It mimics a transient ischemic episode during embryonic development that was linked to NCLP development. Materials and Methods: hDSC were isolated from teeth extracted from patients in the Oral maxillofacial surgery clinic (IRB#2023-80). MTHFR677 genotypes (CC, CT, TT) were identified. Ischemia/reperfusion injury was induced using Billups-Rothenberg hypoxic chambers. Cytotoxic damage was assessed by measuring concentration of lactate dehydrogenase (LDH) released to medium using CyQuant LDH Cytotoxicity Assay (Life Technologies). Samples were collected at multiple time points: T0 (baseline, before hypoxia), T1 (immediately before hypoxia), T2 (24 hours post-hypoxia), and T3 (48 hours post-reperfusion). Total number of cells was assessed at baseline and after recovery from ischemia/reperfusion injury (CyQuant LDH assay after lysis of all cells). The experiments were done in triplicates in culture medium with added 2 μg/mL folic acid and in medium with no folic acid added. 3 Results: Cytotoxicity tests showed no significant differences between hDSC exposed to ischemia/reperfusion injury in medium with or without folic acid using hDSC with different MTHFR 677CT genotypes. Multiplication rates were found to be different in hDSC defined by MTHFR 677 CT genotypes. Multiplication rate equal to 1.2 was found in hDSC with MTHFR 677TT genotype, multiplication rate equal to 4.0 was found in hDSC with MTHFR 677CT genotype, and multiplication rate equal to16.8 was found in hDSC with MTHFR 677CC genotype. It seems that the lower activity of MTHFR conferred by T mutated allele was reflected in magnitude of hDSC multiplication rate. Conclusion: Cells with the MTHFR 677 CC genotype exhibited the highest proliferation rate, followed by CT, while TT genotypes showed the least multiplication rate. These findings suggest that hDSC multiplication rate depended on availability of active folate in the cells. Further research will be done to confirm these results on a larger sample. It will further explore the molecular mechanisms involved in prevention of NCLP by folic acid supplementation.