Position Of Maxillary Incisors Research Articles

Cephalometric Evaluation of the Pre- and Posttreatment Changes after the Correction of Class II Division 1 Malocclusion with Twin Block Appliance in Mixed Dentition.

To evaluate the pretreatment cephalometric records on the dental, skeletal, soft tissue, and incisor relationship with a twin block functional appliance in class II malocclusion patients in and around Mahe; evaluate the posttreatment cephalometric records on the dental, skeletal, soft tissue, and incisor relationship with a twin block functional appliance in class II malocclusion patients in these children; and to compare cephalometrically certain dental, skeletal, and soft tissue points in pretreatment and posttreatment cephalograms in them. This study was conducted on 20 class II patients in the mixed dentition period, who were treated with twin block therapy. Each had to meet the following criteria-(1) skeletal class II malocclusion with retrognathic mandible; (2) full cusp class II molar relationship; and (3) an angle of ANB of 50 or greater at the start of treatment. All patients wore the appliance 24 hours/day. The pretreatment cephalometric head films for the group were taken using standard cephalometric X-ray equipment. The length of time required to achieve a class I molar relationship was assessed. Appointments during the twin block phase were scheduled at intervals of 8 weeks. Lateral head films were obtained again at the posttreatment follow-up stage. There was a significant increase in effective mandibular length, ramus height, SNB, ANB, overjet, overbite, and I to NA (mm and degrees) after twin block therapy. The maxillary incisor position showed a decrease in its value by 4° in five cases. Thus, in the present study, evidence of skeletal and dentoalveolar changes leading to the correction of class II division 1 malocclusion with the twin block functional appliance has been established. However, further studies with a longer period of follow-up and a larger sample are required to substantiate the results of the present investigation. Bimalrag BR, Ephraim R, Ayilliath A, et al. Cephalometric Evaluation of the Pre- and Posttreatment Changes after the Correction of Class II Division 1 Malocclusion with Twin Block Appliance in Mixed Dentition. Int J Clin Pediatr Dent 2024;17(7):783-789.

Analysis of maxillary teeth and soft tissue profiles among Tibetan and Han Chinese females with facial symmetry for orthodontic treatment planning.

The evaluation of maxillary teeth and soft tissue profiles is a critical component of orthodontic diagnosis and treatment planning. This study aimed to evaluate the correlation between the sagittal position of maxillary anterior teeth and facial profile esthetics among Tibetan and Han Chinese adult females for optimizing orthodontic diagnosis and treatment planning. A total of 100 Tibetan Chinese and 100 Han Chinese adult females with good facial symmetry were recruited. The smiling facial profile images with the maxillary central incisors and forehead in full view were taken based totally on the same standard. The photo measurement and head position were adjusted using the picture-enhancing software. The reference traces associated with forehead inclinations were utilized to assess the anteroposterior (AP) positions of the maxillary central incisors. The results showed that a round forehead was the dominant forehead shape for Tibetan (93%) and Han (55%) Chinese females. In Tibetan females, 85% of the maxillary central incisors were found to be located between the forehead's anterior limit line (the Gall line) and the goal anterior limit line (the Fall line), with 15% located posterior to the Fall line. This distribution manifested a strong association with incisor position and forehead inclination (R2 = 0.742). In Han females, 83% of the maxillary central incisors were located between the Fall line and the Gall line, with 12% posterior to the Fall line and 5% anterior to the Gall line. The positions of the maxillary central incisors exhibited a strong relationship with forehead inclination (R2 = 0.827). The maxillary central incisors were close to the aesthetic line in both ethnic groups, while forehead inclinations were correlated with AP maxillary incisor position. These findings demonstrated that there was a close relationship between the incisor position of Tibetan and Han females with facial symmetry and the forehead FFA factor, indicating a reference in oral hard and soft tissues for optimizing orthodontic diagnosis and treatment planning in terms of facial contour.

Measurement of distance between maxillary central incisors and incisive papilla in dentate individuals.

Objective: To measure the distance amongst the incisive papilla’s centre and posterior border to the incisal edge of the upper central incisors in dentate individuals.Methodology: This descriptive cross-sectional study was conducted at Department of Prosthodontics at Isra Dental Col-lege, Hyderabad from May, 2020 to Feb, 2021. During study period, 200 patients aged between 20-40 years of either gender were included. Impressions and casts made. On the cast and distance measured and recorded for maxillary central incisor and incisive papilla with the help of vernier calliper.Results: Mean distance between maxillary central incisive papilla’s centre was 9.20mm while it was 12.47mm from up-per incisor to the incisive papilla’s posterior border. Distance among the maxillary central incisor to the incisive papilla’s center and posterior border were significant statically in both genders.Conclusion: While fabricating removable prosthesis, the results of current study may used as primary point for position of maxillary incisors.
 Key words: Anatomical landmarks, Central incisors & Incisive papilla. Removeable prosthesis

EVALUATION OF DENTOALVEOLAR COMPENSATION IN DIFFERENT SKELETAL MALOCCLUSIONS IN BENGALEE POPULATION- A CEPHALOMETRIC STUDY

Introduction: Humans have been aware of facial esthetics from prehistoric times. An 'esthetically pleasing face' is described as one in which various facial features are well proportioned and balanced from both 'frontal and prole' view. Evaluating the face in prole is an integral part of a complete orthodontic diagnosis. The labiolingual inclination and anteroposterior (AP) position of maxillary incisors have a crucial effect on the appearance of the smiling prole. Aims: To evaluate and compare dentoalveolar compensations in various skeletal malocclusions. The Cross sectional study Materials and methods: , this Study was conducted from January 2018 to June 2019 at Guru Nanak Institute of Dental Sciences and Research, panihati, Kolkata- 7 00114. 120 patients were taken in our study. Result: In the present study mandibular central incisor to SN shows statistically signicant difference in mean value when intergroup comparison were made between control group with group-II, and group-III, between group- Mandibular incisors are proclined labially in skeletal class- II malocclusion, while mandibular incisors were found upright or retroclined in skeletal class-III malocclusion. In Group-II (skeletal Conclusion: Class- II malocclusion) upper incisors are proclined in the upper jaw, and lower incisor proclined in lower jaw.

Lateral cephalometric values of FKG ULM students Banjar ethnic according to Steiner analysis

Objectives: This study aimed to determine the value of dentocraniofacial measurements of FKG ULM students from Banjar ethnic in terms of lateral cephalometric radiography using Steiner analysis.
 Materials and Methods: Cephalometric measurements were performed using the Steiner analysis method on skeletal landmarks: SNA, SNB and ANB; dental: UI-NA, LI-NB, and interincisal angle. Data analysis was performed by descriptive statistical method.
 Results: The average skeletal and dental value of the FKG ULM students from Banjar ethnic at the SNA angle is 86.31°± 4.49°, the SNB is 81.33°± 4.39°, the ANB is 4.98°± 2.05°, the UI-NA angle is 19.69°± 8.22°, the LI-NB angle is 28.65°± 6.76°, the UI-NA distance is 4.45± 2.86 mm, the LI-NB distance is 8.58± 3.19 mm and the interincisal angle is 126.43°± 10.51°.
 Conclusion: The dental and skeletal averages showed that the FKG ULM students from Banjar ethnic had more prognathic maxillary and mandibular positions and more protrusive maxillary and mandibular incisor positions than the normal standard of Steiner's analysis.

Anteroposterior relationship of the maxillary central incisors to the forehead in adult Chinese females

Objectives: The objectives of the study were to evaluate the anteroposterior (AP) relationship of the maxillary central incisors to the forehead in adult Chinese females. Material and Methods: The study sample consisted of 100 lateral smiling photographic images of adult Chinese females who were seeking orthodontic treatment (mean age = 24.0 + 6.5 years old). The study sample was compared to a control sample consisting of 100 images of adult Chinese females with harmonious facial profiles downloaded from the internet. The images were resized and rotated to the upright head position in an image editing software. Reference lines were constructed to evaluate forehead inclinations and AP positions of the maxillary central incisors. Results: In the control sample, 80% of the maxillary central incisors were positioned between the facial axis point of the forehead (FFA) and the glabella. About 13% were positioned posterior to the FFA point and 7% anterior to the glabella. In the study sample, 31% of the maxillary central incisors were positioned between the FFA point and glabella, 52% posterior to the FFA point, and 18% anterior to the glabella. There was a strong correlation between the position of the maxillary central incisors and forehead inclination in the control sample (r2 = 0.827). The difference in AP maxillary central incisor position relative to the forehead between the two groups was found to be statistically significant (P = 0.000). Conclusion: The forehead may be an important landmark when evaluating the AP position of maxillary incisors in adult Chinese female patients.

Comparison between clear aligners and 2 × 4 mechanics in the mixed dentition: a randomized clinical trial.

To compare the efficacy and efficiency between clear aligners and 2 × 4 fixed appliances for correcting maxillary incisor position irregularities in the mixed dentition. The sample comprised 32 patients from 7 to 11 years of age randomly allocated into two parallel treatment groups: the clear aligners group, 14 patients (6 girls, 8 boys) with a mean initial age of 9.33 years (standard deviation [SD] = 1.01) treated with clear aligners; and the fixed appliances group, 13 patients (9 girls, 4 boys) with a mean initial age of 9.65 years (SD = 0.80) treated with partial (2 × 4) fixed appliances. Digital models were acquired before treatment and after appliance removal. Primary outcomes were incisor irregularity index and treatment time. Secondary outcomes were arch width, perimeter, length, size and shape, incisor leveling, incisor mesiodistal angulation, plaque index, and white spot lesion formation (International Caries Detection and Assessment System index). Intergroup comparisons were evaluated using t-tests or Mann-Whitney U-tests with Holm-Bonferroni correction (P < .05). Treatment time was approximately 8 months in both groups. No intergroup differences were observed for changes in any of the variables. Similar posttreatment arch shapes were observed in both groups. Clear aligners and 2 × 4 mechanics displayed similar efficacy and efficiency for maxillary incisor position corrections in the mixed dentition. The choice of appliance should be guided by clinician and family preference.

Maxillary incisor position-based orthodontic treatment with miniscrews

Traditionally, orthodontic diagnosis and treatment have primarily involved the assessment of skeletodental relationships, with a particular focus on the mandibular dentition. Recently the focus has shifted towards the maxillary incisors as a starting point for facial esthetics with growing demands for facial esthetics. Three-dimensional maxillary incisor position (MIP) plays a pivotal role in improving facial esthetics in smiling and resting positions. With the advent of miniscrews, biomechanical force application in orthodontic treatment has become simpler due to absolute anchorage. Miniscrews allow clinicians to move teeth more precisely and easily in three dimensions according to the treatment plan, which was challenging or impossible with conventional biomechanics. Therefore, MIP using miniscrews should be a starting point for esthetic treatment planning.

Maxillary incisor-based objectives in present-day orthodontics

<h2>ABSTRACT</h2> Orthodontists should be familiar in examining all the components of a smile. A parallel position of the facial aspect of the incisor crown to the face is considered to be the most aesthetic position of the maxillary incisor. A more anterior position of the maxillary central incisors has been shown to be more acceptable than a more posterior position. Exposition of the incisor should not be larger than 3 mm in relationship to the upper lip. The lack of objective criteria to position incisors may be a first step to make the patient become dissatisfied with the treatment result. This paper discusses the ideal buco-ligual inclination for maxillary central incisor, and their horizontal and vertical position. A simple way to determine a virtual goal for maxillary incisor position, using digital tools, will be explained as well as how to transfer the occlusal plane to 3d planning softwares. A clinical case is presented using the Glabellar vertical line, the Mid-forehead vertical line and the Functional Esthetical Oclusal Plane as tools to determine where the maxillary central incisors should be positioned for optimal esthetic results.

Customized maxillary incisor position relative to dentoskeletal and soft tissue patterns in Chinese women: A retrospective study.

ObjectiveTo provide reliable prediction models based on dentoskeletal and soft tissue variables for customizing maxillary incisor positions and to optimize digitalized orthodontic treatment planning.MethodsThis study included 244 Chinese women (age, 18–40 years old) with esthetic profiles after orthodontic treatment with fixed appliances (133 in group I 1° ≤ The angle between the nasion [N]-A point [A] plane and the N-B point [B] plane [ANB] ≤ 4°; 111 in group II 4° < ANB ≤ 7°). Dental, skeletal, and soft tissue measurements were performed on lateral cephalograms of the participants. Correlation and multiple linear regression analyses were used to determine the influence of dentoskeletal and soft tissue variables on maxillary incisor position.ResultsThe ideal anteroposterior position of the maxillary incisor varied between sagittal skeletal patterns. The position of the maxillary incisor correlated with the sagittal discrepancy between the maxilla and the mandible (ANB), protrusion of the midface, nasal tip projection, development of the chin, and inclination of both the maxillary and mandibular incisors. Distance from the maxillary central incisor to nasion-pogonion plane predicted using multiple linear regression analysis was accurate and could be a practical measurement in orthodontic treatment planning.ConclusionsInstead of using an average value or norm, orthodontists should customize a patient’s ideal maxillary incisor position using dentoskeletal and soft tissue evaluations.

Determinants of Upper Lip Form: An Analysis Using Geometric Morphometrics

Orthodontics and orthognathic surgery can alter an individual's facial form, and it is the clinician's goal to predictably control changes in the facial soft tissues to achieve treatment goals. Within the facial profile, controlling projection of certain structures, such as the chin, is predictable, as the soft-tissue response to hard-tissue changes in such areas is predictable. The upper lip, on the other hand, presents a different challenge. While multiple studies have shown relationships between advancement of the upper incisor and advancement of the soft-tissue lip, unlike the chin, the anterior position of the upper lip is only a small component of upper-lip profile esthetics. Given the structure of the upper lip, the angulation plays a prominent role in upper-lip profile esthetics besides just its anteroposterior projection. No direct or indirect relationships have been established between the maxillary incisal orientation and upper-lip angulation. The clinical significance in understanding the upper lip to hard-tissue relationship is to predictably control the upper-lip angulation in orthodontics and/or orthognathic surgery in patients with dentofacial deformities. In the absence of reliable data, planning often becomes overly subjective or arbitrary, which could lead to poor esthetic outcomes. To the author's knowledge, there are no studies that analyze the relationship between the hard tissues and the upper-lip angulation. This is presumably the case because of the difficulty in comparing the contours of the hard and soft tissues in these non-linear structures. Any “parallelism” cannot be reliably measured in a reliable or quantitative way using conventional cephalometric or other linear techniques.A retrospective cross-sectional study was designed to analyze cone beam computerized tomography (CBCT) scans from 104 patients, using geometric morphometrics. The contour of the hard tissue was evaluated by taking a point below anterior nasal spine (ANS) at the point of greatest convexity between ANS and maxillary alveolus, as well as the most anterior point of the maxillary alveolar bone between the central incisors. Once these points were identified, 3 semi-landmarks were taken at equidistant points between these in order to best trace the curvature of this area. For the soft-tissue analysis, subnasale and labrale superioris were identified and, once again, 3 semi-landmarks were taken at equidistant points between these landmarks to map the upper-lip curvature.The data were then compiled, giving a total of 1040 data points, 520 hard-tissue and 520 soft-tissue points. While the results of the principal components analysis and partial least squares are pending, the initial data show a positive correlation between contour of the alveolar bone and teeth and the upper-lip position and form.Based on these findings, it appears that the upper-lip contour in the dentofacial deformity patient can be predictably controlled by manipulating the position of the maxillary alveolus and incisor position via orthodontic and surgical means.

Accuracy of Virtual Surgical Planning with Mandible-first Surgery and Factors that may Affect It

Planning bimaxillary orthognathic surgery has become much easier and the workflow more streamlined with the advent of virtual surgical planning (VSP). Among its advantages, VSP allows for easy transition between performing maxillary or mandibular surgery first, as it eliminates the cumbersome process of reverse model surgery. In this experience of performing mandible surgery first, it was observed that the osteotomy gaps at the piriform and zygoma appeared to be different than what was predicted on the VSP. The present study was initiated to compare the planned movements to the actual achieved surgical position of the maxilla after correction of dentoskeletal deformity. The goal of the study was to evaluate the accuracy of a maxillary surgery-first sequence and a mandibular surgery-first sequence. Additionally, the researchers sought to determine if any surgical interventions could mitigate the under-advancement noted in observations.The authors implemented a retrospective audit of 61 patients who underwent bimaxillary orthognathic surgery from January 2017 to September 2020. Exclusion criteria included previous cleft lip/palate surgery, previous orthognathic surgery, lack of a post-surgical CBCT, non-sagittal split osteotomies of the mandible, or if there was greater than 3mm vertical deviation in planned and achieved surgical position of the central incisor based on intraoperative incisor show. Patients were divided into 2 groups based on the surgical sequencing used; 28 patients had maxillary surgery performed first and 33 underwent mandibular-first surgery. Pre-surgical and post-surgical CBCT scans were analyzed by 3D Systems engineers, with overlays made using the predicted osteotomies and the postoperative CBCT scans. A pre-determined set of skeletal landmarks were measured on the virtual surgical plan and the actual postoperative images, and the difference between the planned and actual position was calculated for each reference point for each patient. The absolute value of each difference was then calculated, and a series of 2 sample T-tests was performed to compare the average absolute difference between planned and actual position between groups.The absolute values of the linear (mm) and angular (°) measurement differences between planned and postoperative results demonstrate statistically significant differences in accuracy between the 2 groups, with greater deviation in the mandible-first group. The maxillary central incisors were under advanced in the anterior-posterior (AP) direction in both groups. Additionally, a significant difference in reference points ISU1 (AP) and A Point (AP) was noted between the groups, indicating that greater inaccuracy lies within the mandibular-first group. However, the majority of data points show deviation from the surgical plan less than or equal to 2mm and 4 degrees, meeting previously described success criteria.1,2To further evaluate the larger maxillary under advancement in the mandible-first surgery cohort, the researchers sub-divided the mandible-first surgery group to evaluate factors that may explain the difference, 1 factor being the type of fixation used for sagittal split segments, rigid or non-rigid. When comparing the average linear measurements, the non-rigid fixation group showed less accuracy when compared to the rigid fixation group, and this was statistically significant (P-value: .007).In conclusion, the findings of the present study demonstrate that virtual surgical planning can be less accurate in predicting the maxillary incisor position when mandibular surgery is performed first, but this inaccuracy is within the acceptable range and can be mitigated by more rigid fixation of the mandible.

Characteristics of Skeletal Archial Analysis Facial Patterns in Adult Obstructive Sleep Apnea

IntroductionSkeletal archial analysis in adult OSA has not been characterized. The specific aim of this study was to characterize archial analyses of adult subjects with known OSA. The primary research question of this study was: “What is the frequency of skeletal patterns from archial analysis in adult OSA subjects?” The authors hypothesized that adult subjects with OSA will follow a retrusive pattern skeletal archial analysis with high correlation with OSA severity. Materials and methodsA retrospective cohort study of adult polysomnogram (PSG)-confirmed OSA subjects’ charts was designed from subjects who presented to Allegheny General Hospital Division of Oral and Maxillofacial Surgery between January 1, 1992, and December 31, 2017. Inclusion criteria included PSG-confirmed OSA (AHI > 5), diagnostic lateral cephalometric radiographs, and demographic and diagnostic data. Exclusion criteria included subjects with a history of maxillofacial trauma or tumor surgery, craniofacial syndromes, and inadequate chart records. Independent predictor variables were age, sex, body-mass index (BMI), anterior arc independent (continuous data), and combined horizontal and vertical analyses (categorical data). Lateral cephalometric radiographs were analyzed with Dolphin software (v. 11.8) for Sassouni Plus archial analysis. Anterior arc analysis was recorded for maxillary incisor position to ANS (U1 - ANS arc), Point B to Point A arc (B - A arc), and pogonion to ANS arc (Pg - ANS arc). Skeletal facial types were categorized into 27 distinct facial types. Statistical analysisStandard descriptive and Spearman correlation (□) analysis was used with Excel. Results were reported as mean, standard deviation, and percentages. Standard error of measurement (SEM) and post-hoc power analysis were completed. Statistical significance was set at the P < .05 level. ResultsA total of 171 subject charts that met the inclusion criteria were included in this study. The cohort consisted of 124 females (73%). The cohort mean for age was 47 years (Standard deviation [SD] 11), for BMI 31 (6.5), for AHI 42 (30.5), for ESS 13 (4.9), and for nO2 81% (11). All ICC were greater than or equal to 0.90. Skeletal archial analyses revealed that the most frequent skeletal patterns were Class III at 44.7% (77/171), bimaxillary retrusion at 27% (46/171), Class II at 21.1% (36/171), Class I at 6.6% (11/152), and bimaxillary prognathism at 0.6% (1/171). Relative to the anterior arc, maxillary position was retrusive in 82.2% (141/171), ideal in 11.2% (19/171), and protrusive in 6.6% (11/171) of subjects. Also, relative the anterior arc, the mandible was in an ideal position in 45.3% (78/171), retrognathic in 33.6% (57/171), and prognathic in 21.1% (36/171) of subjects. Long vertical skeletal pattern was most frequent at 81.6% (140/171), normal at 14.5% (25/171), and short at 3.9% (7/171) of subjects. The most frequent skeletal patterns were Maxilla Retro, Mand Ideal AP; Long Vertical (49/171, 28.9%), Bi-Skeletal Retro AP; Short Vertical (41/171, 23.7%), and Maxilla Retro, Mand Prog AP; Long Vertical (26/171, 15.1%). There were only weak correlations between all independent and dependent variables (range P = .05 to .19). ConclusionWithin the limitations of this study, maxillary and bimaxillary retrusion patterns were frequent horizontal archial analysis skeletal positions as was long lower facial height. Most skeletal patterns involved maxillary retrusion, generally with long vertical lower face. All of the horizontal archial skeletal positions had weak correlations with severity of adult OSA. Additional research may be required to fully analyze the full diagnostic potential of skeletal archial analysis in diagnosis and treatment planning of subjects with OSAS.

Archial Skeletal Analysis is not a Significant Predictor of Adult OSA Syndrome Severity

IntroductionArchial analyses may be a useful tool in the diagnosis and treatment planning of adult OSA. The purpose of this study was to evaluate the association of vertical and horizontal archial analyses on predictors of the severity of OSA. The primary research question of this study was: “Does facial skeletal archial analysis predict severity of OSA?” The authors hypothesize that archial analyses will predict severity of adult OSA. Subjects and methodsA retrospective cohort study of adult polysomnogram (PSG)-confirmed OSA subjects’ charts was designed from subjects who presented to Allegheny General Hospital Division of Oral and Maxillofacial Surgery between January 1, 1992, and December 31, 2017. Inclusion criteria included PSG-confirmed OSA (AHI > 5), diagnostic lateral cephalometric radiographs, and demographic data. Exclusion criteria included subjects with a history of maxillofacial trauma or tumor surgery, craniofacial syndromes, and inadequate chart records. Independent predictor variables were age, sex, body-mass index (BMI), anterior arc independent (continuous data), and combined horizontal and vertical analyses (categorical data). Skeletal facial types were categorized into 27 distinct facial types based on combined anterior horizontal and vertical arcs. Primary outcome variable was severity of OSA as defined by apnea-hypopnea index (AHI). Secondary outcome variables included Epworth sleepiness scale (ESS) and lowest oxygen saturation (nO2). Lateral cephalometric radiographs were analyzed with Dolphin software (v. 11.8) for Sassouni Plus archial analysis. Anterior arc analysis was recorded for maxillary incisor position to ANS (U1 - ANS arc), Point B to Point A arc (B - A arc), and pogonion to ANS arc (Pg - ANS arc). Statistical analysisStandard descriptive analysis, multiple linear regression on continuous variables, and multinomial logistic regression on categorical and dummy variables were performed using XLSTAT. Stratified by sex, multilinear regression was performed on anterior arc analyses. Continuous variables (median values) and categorical data were transformed to dummy variables for multinomial logistic regression. Results were reported as mean, standard deviation, and odds ratio (OR). Standard error of measurement (SEM) was completed on repeated cephalometric analyses of 20 randomly selected radiographs. Statistical significance was set at P < .05 level. ResultsA total of 171 subject charts that met the inclusion criteria were included in this study. The cohort consisted of 124 females (72.5%). The cohort mean for age was 47 years (Standard deviation [SD] 11), for BMI 31 (6.5), for AHI 42 (30.5), for ESS 13 (4.9), and for nO2 81% (11). All SEM were greater than or equal to 0.90. Stratified by sex, and controlling for age and BMI, no statistically significant associations for anterior archial analyses (U1 - ANS arc, B - A arc, or Pg - ANS arc) and severity of adult OSAS were found. Multinomial logistic regression revealed that none of the archial skeletal classifications were significant predictors of the severity of OSAS (AHI OR = 1.0, P = .89; ESS OR = 0.99, P = .70; nO2 OR = 1.0, P = .81). ConclusionWithin the limitations of this study, when controlling for age, sex, and BMI, anterior horizontal archial analyses were not significantly associated with, and archial skeletal facial types were not significant predictors for, OSAS severity as defined by AHI, ESS, or nO2. Additional research may be required to fully analyze the full diagnostic potential of skeletal archial analysis in diagnosis and treatment planning of subjects with OSAS.

Relationship of anteroposterior position of maxillary central incisors with the forehead in an adult Iranian subpopulation: A cross-sectional study

This study aimed to assess the relationship of the anteroposterior position of maxillary central incisors with the forehead in an Iranian subpopulation residing in Kermanshah city. In this cross-sectional study, 12 orthodontists were requested to analyse full-smile profile photographs with complete maxillary incisor and forehead show in 70 patients with optimal facial harmony (35 males and 35 females) as the control group and 140 patients without optimal facial harmony (70 males and 70 females) as the test group. The inclusion criteria were (I) males and females between 18-60 years seeking orthodontic treatment and (II) willingness for participation in the study. The exclusion criteria were (I) presence of severe craniofacial anomalies, and (II) history of orthodontic treatment. The photographs were traced and analysed using Digimizer Image Analysis software 5.3.5. Data were analysed using STATA version 14.2 via independent t-test and linear regression. A significant difference existed in the anteroposterior position of maxillary incisors in males between the test and control groups (P=0.002). However, this difference was not significant in females of the two groups (P=0.77). A significant difference was noted in the anteroposterior position of maxillary incisors between males and females in the test group (P=0.001) but not in the control group (P=0.80). The frontal angle had a significant correlation with gender and anteroposterior position of maxillary incisors in both groups (P<0.001). According to the results, the anteroposterior position of maxillary incisors was significantly different in the test and control groups. The maxillary incisors in males were more retruded than in females. Also, the frontal angle had a significant correlation with the anteroposterior position of maxillary incisors, and by 1° increase in the frontal angle, the incisors were protruded by averagely 0.307mm.

A Novel Device to Measure the Optimal Position of Central Incisors in Anteroposterior Dimension Clinically: “P” Device

Facial esthetic has always been a concern for humans for ages. The anteroposterior (AP) position of central incisors plays a key role in building facial esthetic in a smiling profile view. There have been various cephalometric, profilometric, and photographic methods used in the past to assess and predict the AP position of maxillary incisors in their optimal esthetic position. Our new device will help to predict, assess, and measure the optimal AP position of maxillary central incisors clinically using the glabella as a landmark.

Influence of incisor position control on the mandibular response in growing patients with skeletal Class II malocclusion

This study aimed to test whether control in maxillary and mandibular incisor position, during treatment with an acrylic splint Herbst appliance, could influence the mandibular response in growing patients with skeletal Class II malocclusion. The lateral cephalograms of 61 patients (mean age, 12.3years; standard deviation, 1.6) with skeletal and dental Class II malocclusion were retrospectively analyzed both at baseline and after Herbst appliance removal, using a modified Pancherz cephalomeric analysis. Forty-five patients had received miniscrew in the mandibular arch to control mandibular incisor anchorage. In 21 patients, the maxillary incisors had been proclinated before starting the treatment for deepbite and maxillary incisor lingual inclination. All the patients were categorized a posteriori into 2 homogeneous groups, according to dental overjet reduction: 30 patients with dental overjet reduction (DR) and 31 patients without dental overjet reduction (NDR). Both groups presented a significant skeletal correction. However, the change was significantly greater in the NDR group than in the DR group (P<0.01). The mandibular bone base reached a median value of 4.0mm (interquartile range, 2.5) in the NDR group vs 1.1mm (interquartile range, 2.8) in the DR group (P<0.001). The 2 groups were also significantly different in terms of the positional change of maxillary incisor, which was proclinated in group NDR and lingualized in group DR (P<0.001). The results showed that dental control of overjet was beneficial to improve the effectiveness of Herbst treatment in increasing mandibular length in growing patients with skeletal Class II malocclusion.

Aesthetic evaluation of the labiolingual position of maxillary lateral incisors by orthodontists and laypersons

BackgroundThe maxillary anterior teeth play a crucial role in smile aesthetics. Previous studies regarding the importance of maxillary lateral incisors for smile aesthetics concentrated on their size, incisor edge level, and inclination, etc. However, the aesthetic effect of lateral incisor movement in the spatial position has not been studied yet. Therefore, the purpose of this study was to explore the influence of the labiolingual position of maxillary lateral incisors on the aesthetic perception of smiles by orthodontists and laypersons, as well as analyze differences in this perception between male and female raters.MethodsA three-dimensional (3D) dental model was generated from the photograph of a man’s smile using iOrtho7.0 software (Time Angel, Wuxi, China). Based on this model, seven images were generated with different labiolingual positions of the maxillary lateral incisors in 0.5 mm increments (+ indicating labial translation, and—indicating lingual translation). The images were evaluated by 86 orthodontists and 161 laypersons using a visual analog scale, with lower scores indicating less attractiveness. Data were analyzed using Student’s t test and one-way analysis of variance with post hoc test.ResultsThere was no significant difference in smile ratings by males and females. Orthodontists assigned lower scores to all images than laypersons. The smile at + 1.5 mm was considered the least attractive by orthodontists, while smiles at + 1.5 mm and − 1.5 mm were regarded as the least attractive by laypersons. The smile at 0 mm was evaluated as the most attractive by all raters. Laypersons gave different scores to smiles at 0 or − 0.5 mm, but orthodontists did not.ConclusionsThe labiolingual position of maxillary lateral incisors does affect the perception of smile aesthetics. Orthodontists may rate smile aesthetics more critically than laypersons. Therefore, communication and discussion between orthodontists and patients is needed to achieve better therapeutic and aesthetic outcomes.

Planning and orthodontic preparation for maxillary incisors reshaping.

ABSTRACTIntroduction: Having a beautiful smile is the main desire of people seeking dental treatment. To achieve this goal, many variables must be considered. These include tooth alignment, color, shape and size, besides their harmonious relationship with the lips and face. An individualized diagnosis is essential to achieve the best result. Within this context, facial analysis and the characteristics of shape, size and position of maxillary incisors play a key role.Methods: This paper describes clinical situations in which interdisciplinary treatment was performed to achieve esthetic results in a conservative manner and ensuring greater stability. In most cases requiring reshaping of maxillary incisors for esthetic reasons, prior orthodontic movement is essential. The main focus of this paper is to discuss the many variables involved in these situations.Results and Conclusion: The results of treatments described in this paper were obtained by means of a multidisciplinary approach, involving Orthodontics and Esthetic Dentistry, acting in harmony and recognizing their possibilities and limitations, in order to offer patients the best esthetic solution for their smile. The best treatment option is not always the easiest or fastest. The dentist, as a health professional, should consider the patients’ wishes but also perform treatments with minimal intervention, and the best and most predictable esthetic result, also focusing on function and health.

Correlations between objective measurements and subjective evaluations of facial profile after orthodontic treatment.

ObjectiveTo investigate the correlations between objective measurements and subjective evaluations of post-treatment facial attractiveness.MethodsTen orthodontists rated the subjective visual analog scale (VAS) scores of the facial profiles of 95 patients who had undergone orthodontic treatment. Post-treatment cephalograms and photographs were used. Eleven soft tissue measurements and eight maxillary incisor measurements were constructed and analyzed. Correlations between objective measurements and subjective VAS scores were evaluated using Pearson correlation and quadratic regression analysis.ResultsThe VAS scores of different facial proportions were all correlated with the total VAS score. Among soft tissue measurements, the distances from the upper and lower lips to the E line, H angle, forehead inclination, distance from lower lip to the H line, and pogonion-menton angle were negatively correlated with the VAS scores. The Z angle, with a parabolic distribution, was also correlated with the VAS scores. Among maxillary incisor measurements, the distance from the maxillary incisors to the forehead’s anterior limit line and the angulation of the maxillary incisors to the APo line were negatively correlated with the VAS scores.ConclusionsSeveral soft tissue and maxillary incisor position measurements were correlated with facial profile evaluation and therefore might be used to evaluate facial attractiveness.