Natural Head Position Research Articles

Changes in lateral standing posture following orthognathic surgery: a cohort study

Altering neuromuscular and musculoskeletal relationships also affects standing body posture, particularly in the head and neck areas. This prospective cohort study assessed the effects of orthognathic surgery on head posture in the lateral standing view. Thirty-one patients who underwent single-jaw orthognathic mandibular surgery were included. The patients underwent lateral cephalometric and photographic evaluations of their natural habitual posture before and 6 months after surgery. The craniovertebral angle and Frankfort angle (Frankfort horizontal line to true horizontal line angle) were determined and measured using MB-Ruler software. Mandibular positional changes were also measured by superimposing lateral cephalograms and recording changes in the menton point in the vertical and horizontal planes. All data were analysed by paired t-test. The craniovertebral angle increased significantly in patients with Class II malocclusion (P = 0.001) and decreased significantly in Class III patients (P = 0.004). Furthermore, the Frankfort angle was significantly increased in both Class II (P = 0.005) and Class III (P = 0.012) patients. The tendency towards forward head posture decreased in patients with Class II malocclusion, and the lateral neck posture improved. Conversely, a slight but significant tendency towards a forward head posture was observed in Class III patients after surgery. Furthermore, the natural head position changed in both study groups, leading to a more upright head posture.

Automatic Reproduction of Natural Head Position in Orthognathic Surgery Using a Geometric Deep Learning Network.

Background: Accurate determination of the natural head position (NHP) is essential in orthognathic surgery for optimal surgical planning and improved patient outcomes. However, traditional methods encounter reproducibility issues and rely on external devices or patient cooperation, potentially leading to inaccuracies in the surgical plan. Methods: To address these limitations, we developed a geometric deep learning network (NHP-Net) to automatically reproduce NHP from CT scans. A dataset of 150 orthognathic surgery patients was utilized. Three-dimensional skull meshes were converted into point clouds and normalized to fit within a unit sphere. NHP-Net was trained to predict a 3 × 3 rotation matrix to align the CT-acquired posture with the NHP. Experiments were conducted to determine optimal point cloud sizes and loss functions. Performance was evaluated using mean absolute error (MAE) for roll, pitch, and yaw angles, as well as a rotation error (RE) metric. Results: NHP-Net achieved the lowest RE of 1.918° ± 1.099° and demonstrated significantly lower MAEs in roll and pitch angles compared to other deep learning models (p < 0.05). These findings indicate that NHP-Net can accurately align CT-acquired postures to the NHP, enhancing the precision of surgical planning. Conclusions: By effectively improving the accuracy and efficiency of NHP reproduction, NHP-Net reduces the workload of surgeons, supports more precise orthognathic surgical interventions, and ultimately contributes to better patient outcomes.

Methodology for the correction of a CBCT volume from the skull to the natural head position

The orientation of the head during the acquisition of cone beam computed tomography (CBCT) is crucial for accurate cephalometric measurements. However, involuntary head movements during the scan can result in misaligned images. This study presents a method to correct the natural head position (NHP) in CBCT skull images after acquisition. Initially, slices were reorganized, and volumes were oriented in RAI coordinates. Next, the Yaw angle in the axial plane was estimated using the fronto-zygomatic sutures (FZS). The Roll angle in the coronal plane was estimated using the centroids of the ocular cavities. Finally, the Pitch angle in the sagittal plane was measured (by the Sella Turcica (S) and Nasion (N) as reference points) and adjusted to reference values of 3.8° for males and 4.1° for females. These calculated angles are used to adjust the CBCT volumes, aligning the images with the NHP.•The method corrects misalignment in CBCT skull images due to involuntary head movements, ensuring accurate cephalometric measurements.•Reference points like fronto-zygomatic sutures, ocular cavity centroids, and the Sella-Nasion line were used to adjust head position in all anatomical planes.•The approach aligns CBCT volumes to the NHP after capture, reducing errors in cephalometric analysis and enhancing diagnostic accuracy.

Risk of Narrow Upper Airway in Class II Children with Large Horizontal Maxillary Overjet Assessed By Acoustic Reflection: a Case-Control Study.

The aim of this case-control study was to examine upper airway by acoustic reflection in class II children with large horizontal maxillary overjet compared to children with neutral occlusion. The study group included children of 9 to 14 years with class II and large horizontal maxillary overjet (≥ 6 mm) compared to children with neutral occlusion (controls). Acoustic pharyngometry and rhinometry were performed in natural head position. Differences between groups were tested by chi-square test, general linear model (adjusted for age, gender and body mass index [BMI]), and Mann-Whitney test. The study and control group consisted of 37 (boys: 19, girls: 18) and 32 (boys: 16, girls: 16) participants, respectively. No significant differences in age, gender, and BMI were found between the groups. For the acoustic rhinometry measurements significantly increased resistance (P = 0.04), reduced volume (P = 0.03) and distance to minimal cross-section area (MCA) (P = 0.035) were found in the study group, but only for the right nostril. However, significantly reduced MCA for both nostrils was found in the study group (P = 0.025 to 0.04). No significant differences in acoustic pharyngometry measurements were found. Nasal airway dimensions were significantly reduced, and nasal resistance was significantly increased in the study group compared to controls. Thus, class II and large overjet with indication for growth adaptive treatment may be a risk factor for sleep-disordered breathing. In the future, orthodontic paediatric patients may benefit from non-invasive risk assessment of narrow upper airway using acoustic reflection.

Evaluating cranial landmarks for yaw orientation in natural head position: a 3D study.

To assess the symmetry of various cranial anthropometric points used as references for yaw orientation in the natural head position (NHP), relative to the mid-sagittal plane. A prospective analysis using tomography data from 55 patients was conducted. Radiopaque markers, placed on patients in NHP, facilitated head position recording in three planes, with subsequent digital transfer for orientation analysis. Symmetry of eight points (zygomaxillare, zygion, ectoconchion, frontozygomatic suture, stephanion, porion, mastoidale, condylion laterale) was measured against the mid-sagittal plane. Significant asymmetry was observed in the stephanion, frontozygomatic suture, and ectoconchion points (p < 0.05). No significant differences were found in the symmetry of other points (p > 0.05). Findings suggest that stephanion, frontozygomatic suture, and ectoconchion are unreliable for yaw orientation in NHP. Other points, combined with clinical measurements, may offer better reliability.

A comparative study to evaluate the influence of the incisal inclinations of maxillary central incisors in gujarati men and women on the perception of smile esthetics among orthodontists, general dentists and lay persons

The aim of this study is to investigate the influence of different incisal inclinations of the maxillary central incisors in an analysis of full face and close up views of the smile on the perception of smile esthetic in Gujarati men and women between orthodontists, general dentists and laypersons. Frontal smile and Lateral profile photographs were digitally altered at full-face view and close-up view of adult men and women aged 15-30 years were used. The patient wase made to sit with a natural head position. Six incisal labial and lingual inclinations of the central incisors were simulated with changes of 5 degree. Alterations in the labially inclined direction were labeled as positive and those in the palatally inclined direction were labeled as negative. The positions were denominated as follows: 5 ͦ, 10 ͦ, 15 ͦ, ‐5 ͦ, ‐10 ͦ and –15 ͦ, according to incisal inclination changes of the central incisors. To simulate the different incisal inclinations adobe Photoshop CS 8.0 was used. The top limit of the full-face image was a region little above the top of the head and the bottom limit was the base of the neck. The images were randomly assembled in an album that were presented to 40 orthodontists, 40 general dentists and 40 laypersons who evaluated the attractiveness of the images by using Visual Analogue Scale. 10was found to be most attractive incisal inclination.

A new method to orient a 3-dimensional facial model to natural head position: A preliminary report on accuracy and reproducibility

ObjectivesTo establish and validate a novel method to orient a 3-dimensional (3D) facial model to natural head position (NHP) in a stereophotogrammetric system using a 2-dimensional frontal full-face photograph of NHP. Material and MethodsSpecific technique procedure was reported for our method, and in vitro model experiment was performed for accuracy test. A preliminary volunteer study was then planned for reproducibility test. ResultsThe accuracy on a 3D-printed test model was within 0.15°. Within an observational cohort of 22 dental students, the angular deviations of different maxillofacial regions (e.g., central forehead, left and right zygomatic regions, apex of nose and mental region) were no more than 2° between the 3D NHP models acquired with a shorter time-interval (1 h from baseline) or a longer time-interval (7 days from baseline), which were all considered clinically insignificant. In addition, the angular deviations were significantly larger with a 7d-interval than with a 1h-interval, indicting a decline in 3D NHP reproducibility over short time duration. ConclusionThe current method may represent a clinically useful protocol for recording and transferring 3D NHP in stereophotogrammetry. Clinical RelevanceIt may provide reliable and meaningful reference information for evaluating craniofacial morphology, and be of clinical use in the diagnosis, treatment and follow-ups of patients with aesthetic or deformed craniofacial problems.

Using a three-dimensional natural head position precise recording and transferring device to translate the natural head position into a 3-dimensional virtual patient: A dental technique

As computer-assisted surgical design becomes increasingly popular in maxillofacial surgery, the integration of the natural head position (NHP) of a 3-dimensional virtual patient has become a primary problem that orthognathic surgeons have to solve during virtual surgical planning. The present technique describes a way of transferring the horizon orientation of the NHP into a computer-aided design software program with a recently developed NHP recording and transferring device (Patent No. ZL202110992198.6 China). The device can record NHP using 5 marked points which can be visualized radiographically.

Orthognathic surgery improves compromised natural head position and pharyngeal airway in patients with Skeletal Class II or III malocclusion.

Natural head position (NHP), pharyngeal airway and maxillofacial growth pattern are correlated. The author's previous studies proved that following surgical correction of Skeletal Class II malocclusion, the over-extended NHP returned upright, and the pharyngeal airway space (PAS) dimension expanded. The present study compares the post-operative change in NHP and PAS after orthognathic surgery in Skeletal Class II and III malocclusion patients. Patients receiving orthognathic procedures to correct Skeletal Class II or III malocclusions were reviewed in this retrospective study. Pre-operative and 6-week post-operative cone-beam computed tomography datasets were collected. Variables representing the craniofacial pattern, the NHP and the PAS were measured three-dimensionally. Post-operative variables were compared with their pre-operative counterparts using either repeat-measure 2-way analysis of variance or Wilcoxon matched-pairs signed rank test. Thirty cases of Skeletal Class II malocclusion and 13 cases of Skeletal Class III malocclusion were collected. Preoperatively, the inter-group differences were significant in craniofacial pattern (68.14 ± 3.552 degree vs. 79.63 ± 2.497 degree, p < .0001) and the NHP (68.77 ± 11.02 degree vs. 82.83 ± 7.738 degree, p = .0002) while not significant in PAS; after surgery, the intergroup differences in craniofacial pattern and the NHP between groups decreased, and the PAS increased in both groups. Orthognathic surgery may improve compromised NHP and increase PAS in Skeletal Class II and III malocclusion patients.

Truth Lies in the Depths: Novel Insights into Facial Aesthetic Measurements from a U.S. Survey Panel.

Aesthetic facial bone surgery and facial implantology expand the boundaries of conventional facial surgery that focus on facial soft tissue. This study aimed to reveal novel aesthetic facial measurements to provide tailored treatment concepts and advance patient care. A total of n=101 study participants (46 females and 55 males) were presented with 120 patient portraits (frontal images in natural head posture; 60 females and 60 males) and asked to assess the facial attractiveness (scale 0-10; "How attractive do you find the person in the image?") and the model capability score (MCS; scale 0-10; "How likely do you think the person in the image could pursue a modelling career?"). For each frontal photograph, defined facial measurements and ratios were taken to analyse their relationship with the perception of facial attractiveness and MCS. The overall attractiveness rating was 4.3 ± 1.1, while the mean MCS was 3.4 ± 1.1. In young males, there was a significant correlation between attractiveness and the zygoma-mandible angle (ZMA)2 (r= - 0.553; p= 0.011). In young and middle-aged females, MCS was significantly correlated with facial width (FW)1-FW2 ratio (r= 0.475; p= 0.034). For all male individuals, a ZMA1 value of 171.79 degrees (Y= 0.313; p= 0.024) was the most robust cut-off to determine facial attractiveness. The majority of human evaluators (n=62; 51.7%) considered facial implants a potential treatment to improve the patient's facial attractiveness. This study introduced novel metrics of facial attractiveness, focusing on the facial skeleton. Our findings emphasized the significance of zygomatic measurements and mandibular projections for facial aesthetics, with FI representing a promising surgical approach to optimize facial aesthetics. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Comparison of Facial Angular Measurements Between Males and Females Presenting at a Tertiary Care Hospital

Background and Objective: The effectiveness of orthodontic diagnosis and treatment planning is dependent on an accurate assessment of the patient's soft tissue profile. The objective of the study was to compare the facial angular measurements between males and females.Methods: The study comprised 100 volunteers (50 males and 50 females) ranging in age from 12 to 16 years. The respondents were chosen through convenience sampling technique from orthodontics department of children hospital Lahore. Cephalometric and photographic profile analysis was used, with angular measurements based on standard cephalometric and photographic records taken in natural head position. The study included four factors in total.Results: The mean cephalometric and photographic naso-frontal angle was 121.050 and 121.030 respectively, where as cephalometric and phographic measurement in females were 122.240 and 122.840 respectively.Conclusion: There was no significant difference in angular measurements between two genders.Keywords: Photographic analysis, Cephalometric analysis, Naso-labial angle, Naso-mental angle, Naso- frontal angle, Naso-facial angle

Characteristics of head and neck alignment and function of deep cervical flexor muscles in patients with nonspecific neck pain

ObjectivesThe objectives were to compare forward head posture (FHP) in natural and corrected head postures between patients with nonspecific neck pain (NSNP) and controls and to clarify the relationship between natural and corrected head posture angle differences and deep cervical flexor function. This study aimed to provide useful evidence for postural assessment and treatment in patients with NSNP. MethodsIn this cross-sectional study, 19 patients with NSNP reporting a pain score of 3–7 for at least 3 months and 19 participants with no neck pain within the previous 12 months were recruited. To evaluate FHP, the cranial rotation and vertical angles were measured using lateral head and neck photographs. The craniocervical flexion test was used to evaluate deep cervical flexor activation and endurance. We evaluated the head and neck alignment in natural and corrected head postures and the relationship between the degree of change and deep cervical flexor function. ResultsFHP in the natural head posture did not differ between groups. In the corrected head posture, FHP was significantly smaller in the NSNP group than in the control group. In the NSNP group, the cranial rotation and vertical angles were significantly different between the natural and corrected head postures, and the angle difference correlated significantly with deep cervical flexor function. ConclusionsPatients with NSNP show hypercorrection in the corrected head posture, which may be correlated with deep cervical flexor dysfunction. Further investigation into the causal relationship between hypercorrection, deep neck flexor dysfunction, and neck pain is required.

Comparative Evaluation of Horizontal Lip Position With Ricketts Esthetic Plane in Preschool and School-Going Children of Bankura, West Bengal: A Craniofacial Anthropometric Study.

Introduction The horizontal lip position and esthetic plane are two important parameters to define facial beauty, and these factors are always given importance in children undergoing fixed orthodontic therapy. The purpose of this study was to evaluate horizontal lip position in primary and mixed dentition children with class I occlusion and to analyze its association with gender among preschool and schoolchildren of villages in the Bankura district in West Bengal. Materials and methods Researchers screened 437 children for the study and selected those who met the inclusion criteria. A total of 407 children were segregated: 201 children aged three to five years with the flush terminal plane and mesial step in primary teeth and 206 children aged seven to eleven years with class I occlusion in mixed dentition were selected from schools in villages in Bankura district, West Bengal, India. The subjects were instructed to hold the head in the natural head position by looking straight, and points were marked on the nose and chin tip, respectively. A metallic ruler was placed from nose to chin, representing Rickett's esthetic line. The horizontal lip distance to the esthetic plane of both upper and lower lips was measured as a linear distance from the most anterior part of the lip to the metallic ruler. The data were recorded, compared with gender, and statistically analyzed using the Chi-square test using the Statistical Package of Social Sciences software (SPSS version 19.0, 2015, IBM Corp., Armonk, NY). Results The most prevalent horizontal lip distance for both upper and lower lips to the esthetic line for primary and mixed dentition in the Bankura region of West Bengal was category I, where the lip is seen beyond the E plane, followed by category II, where lips are at a horizontal distance in the range of 0-1.5 mm from the esthetic line. A significant correlation of lip position with Rickets aesthetic plane was also illustrious with gender in primary dentition, but a non-significant association with gender was noted in mixed dentition. Conclusion Children with class I occlusion from the Bankura district of West Bengal showed a higher percentage of lip position beyond the esthetic plane in both primary and mixed dentition, which is not in line with the inference of Ricketts's studies on the Caucasian population. There is a definite association between gender and horizontal lip distance in Ricketts esthetic plane. Protrusive upper lips were seen more in males, and retrusive lips were seen more in females. Clinical significance The horizontal lip position with reference to Ricketts esthetic plane has been documented in the literature for adults and teens undergoing fixed orthodontic treatment. However, there is no study done to define these measurements in preschool and school-going children, which can assist in determining future esthetic profiles and in preparing a protocol for early age interceptive orthodontics along with aesthetic rehabilitation of the anterior area of the mouth.

Angular Photogrammetric Analysis for a Young Adult Garhwali Population

Abstract Objectives: The aim of this study is to quantify the average parameters that define the soft-tissue facial profile of a young adult Garhwali population of age 18–21 by means of angular measurement on standardized photographs. Materials and Methods: A sample of 50 Garhwali individuals (25 males and 25 females) between 18 and 21 years of age was obtained with a class I dental relationship. The photographic set-up consisted of a tripod that held a digital SLR camera. The photographic records of the subjects were taken in natural head posture. The obtained records were digitized and analyzed using the Digimizer software program. Twelve measurements were digitally analyzed on each photograph. For statistical evaluation, Student’s-t-test was performed and reliability of the method was analyzed. The results were compared with established soft-tissue profile photogrammetric norms. Results: The Student’s t-test was applied to all variables to determine the influence of sex in the measurements. Two of the angles showed sexual differences: nasofrontal (G–N–Prn, P = 0.001) and mentolabial angle (Li–Sm–Pg, P = 0.002). Nasofrontal angle was found wider in the females while mentolabial angle was found be wider in the males. Conclusion: Orthodontist has the ability to alter facial features and must analyze the soft-tissue facial profile and compare it with standard measurements of the soft- tissue facial profile. The sample’s mean values can be compared against records of participants using the same photogrammetric technique and sharing the same attributes. The results showed sexual differences in two of the measurements: the nasofrontal and mentolabial angle.

Evaluation of natural head position changes in the treatment of class II malocclusions with functional appliance

Objectives: The position of the head to the neck is affected by various factors, including respiratory tract features, temporomandibular joint disorders, type of occlusion, and physical aspects. In addition, malocclusion can negatively affect the head-neck position. The present study aimed to evaluate changes in natural head position following treatment of Class II malocclusions with Farmand II functional appliance. Material and Methods: The present study was implemented as a historical cohort with the before and after design. Pre- and post-treatment lateral cephalometric radiographs of 33 skeletal Class II patients treated with the Farmand II functional appliance were included in the present study. The cephalometric analysis was done by tracing the related lines and landmarks. Facial angles and angles determining the natural head and neck position including craniohorizontal, craniocervical, craniovertical (CCV), and cervical curvature (CCI) were measured. Collected data were entered in Statistical Package for the Social Sciences (SPSS)-version 17 software. Paired t-test was used to evaluate the changes in cephalometric indices before and after treatment. P &lt; 0.05 was defined to be statistically significant for all the tests. Results: The results of the present study, showed a significant reduction in the mean values of A point, nasion, B point (ANB) angle and angle of convexity following treatment (P &lt; 0.001); also, Sella-nasion/Odontoid process tangent (SN/OPT) angle showed a substantial decrease in treated patients (P = 0.033), which is indicative of head flexion following treatment. Moreover, the decrease in the mean values of the craniocervical angles, including True vertical line (NL/VER) and Sella-nasion/true vertical line (SN/VER), suggests downward bending of the head in patients treated with this appliance (P-values of 0.029 and 0.012, respectively). The odontoid process tangent/cervical vertebra tangent (OPT/CVT) angle showed an insignificant increase (P = 0.260). Conclusion: The present study showed that patients treated with the Farmand II functional appliance tend to flex their heads and maintain their cervical vertebra in a more upright and straight position.

Photogrammetric angular measurements as a diagnostic tool for orthodontic treatment planning

Objectives: The aim of the study was to compare and correlate angular measurements of soft-tissue profile between cephalogram and photograph and to identify gender difference. Materials and Methods: Sample size consisted of 100 lateral cephalograms and 100 profile photographs of 100 Indian Bengali population aged 18– 25 years (50 males and 50 females; mean age = 21.28 years). All records were taken in natural head position, centric occlusion, and lips in relaxed position. For evaluation of method reliability, intra-class correlation coefficients (ICCs) were calculated from repeated photographic measurements. Similarly, cephalometric and photographic measurements were compared for assessing Pearson correlation coefficients. Linear regression analyses were done for the variable with correlation coefficients &gt;r = 0.7. Ten angular parameters were used for soft tissue analysis and t-test was used for comparison. Statistical analyses were done using the Statistical Package for the Social Sciences for Windows software version 21.0. Results: The reliability test for photographs was found satisfactory with most measurements showing ICCs ≥ 0.90 and highly significant correlations (P ≤ 0.001) with cephalometric measurements. The N’-Prn’-Pg’ angle was found most effective for female subjects (r2 = 0.82), the N’-Prn’/N’-Pg’ angle for male subjects (r2 = 0.89) and among total subjects, the N’-Prn’/N’-Pg’ angle (r2 = 0.88). Conclusion: Photographs may be used for soft tissue evaluation for diagnosis and treatment planning as an alternative to cephalometric soft-tissue analysis.

Facial Analysis of the Igbo Ethnic Group of Nigeria for the Evaluation of Sexual Dimorphism

Background: Facial analysis defines the measurement of soft tissue in the face used in forensics, anthropology, artistic design, and facial reconstruction. The study aims to evaluate the sexual differences in facial parameters among the Igbo ethnic group of Nigeria.&#x0D; Methods: 400 (200 males and 200 females) subjects of Igbo origin volunteered for the study. Each subject's frontal view photographs were taken in the Natural Head Position (NHP) and analyzed using Pro-Image Facial Software Version 2 to evaluate the nasal width, nasal height, mouth width, facial width, facial height, inner canthal distance, and outer canthal distance. Data obtained were analyzed with IBM SPSS (version 23) and independent T-test as an inferential statistic.&#x0D; Results: The result showed that NW was (M=5.16±0.65, F=5.34±0.53, t=-2.91, p=0.00), NH was (M=5.61±0.62, F=5.26±0.57, t=5.92, p=0.00), MW was (M=6.64±0.7, F=6.54±0.71, t=1.46, p=0.14), FW was (M=16.17±1.31, F=15.07±2.04, t=6.39, p=0.00), FH was (M=16.63±1.11, F=16.08±1.31, t=4.36, p=0.00), En was (M=4.62±0.46, F=4.31±0.47, t=6.75, p=0.00) and Ex was (M=12.23±0.86, F=12.16±1.01, t=0.82, p=0.41).&#x0D; Conclusion: The nasal width and Height, facial width and height, and inner canthal distance show gender differences among the Igbo ethnic group of Nigeria. This study will have a practical application in Forensics, Anthropology, Artistic and Industrial design, and to medical professionals involved in facial reconstruction.

Significance of natural head position (NHP) in orthodontic diagnosis: A review

Significance of natural head position (NHP) in orthodontic diagnosis: A review

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

Comparative Evaluation of the Relationship Between Airway Inadequacy, Head Posture, and Craniofacial Morphology in Mouth-Breathing and Nasal-Breathing Patients: A Cephalometric Observational Study.

The process of respiration is the primary factor of the posture of the jaws and tongue. Thus, a changed respiratory form like mouth breathing can change the posture of the head, jaw, and tongue. This, in turn, could change the equilibrium of pressure on the jaws and teeth thus affecting jaw growth and teeth positions. The influence of nasorespiratory function on craniofacial growth has stimulated interest and debate for more than a century. Mouth breathing is the reason for numerous orthodontic glitches such as a mouth breather's face evolving aberrantly because of of functional disruptions triggered by chronic airway obstruction. The relationship between nasorespiratory function and dentofacial development remains controversial despite the long-standing clinical concern of orthodontists, so there was a need to evaluate and compare the relationship between head posture, airway inadequacy, and craniofacial morphology in mouth breathers and nasal breathers. Forty patients were selected and divided equally into two groups: mouth breathers and nasal breathers. Patients were diagnosed as mouth breathers based on physical examination and a history of chronic allergic rhinitis, adenoid, and tonsil enlargement. Lateral cephalograms were taken for all patients in the natural head position (NHP) with the Planmeca Proline XC Dimax3 x-ray machine (Planmeca, Helsinki-Uusimaa, Finland). All lateral cephalograms were traced and analysis was done to check airway, head posture, and craniofacial morphology. Descriptive statistics were performed to obtain the means and standard deviation of all the sample sizes. Unpaired t test was performed between nasal breathers and mouth breathers to check and evaluate the relationship. Mouth-breathing patients varied from nasal-breathing patients in airway adequacy and craniofacial morphology. A little, but not statistically significant, difference was seen in head posture between the two groups. Early interception of mouth breathing in patients could be very helpful, as the postural changes in the mouth-breathing patients, if continued for a longer period of time, could be the reason for severe skeletal deformities as well as dental malocclusion.