Orthognathic Surgical Treatment Research Articles

Orthognathic Surgical Treatment With 3D Virtual Surgical Planning

Orthognathic Surgical Treatment With 3D Virtual Surgical Planning

Clinical evaluation of greater palatine artery hemodynamics in Le Fort I osteotomy

ObjectiveLe Fort I osteotomy (LIO) is a widely known standard orthognathic surgical treatment. However, complications such as osteonecrosis of the jaw due to poor postoperative blood flow to tissues of the maxilla have been reported. This study measured the hemodynamics of the greater palatine artery (GPA) in patients who underwent LIO to explore the factors that affect postoperative blood flow. MethodsWe included 15 patients who underwent LIO and sagittal split ramus osteotomy (SSRO), and 8 patients, who only underwent SSRO, were included as controls. Preoperative, intraoperative, and postoperative blood flow in the oral mucosa anterior to the foramen magnum was measured with a laser Doppler blood flow meter. ResultsOn average blood flow at immediately after downfracture in LIO patients reduced to 24.8% of baseline blood flow and patients who underwent anterior maxillary movement had a lower recovery rate at any time. Multiple regression analysis showed that the greater the maxillary anterior shift and the longer the time from maxillary disarticulation to fixation (mandibular fracture time: DFT), the more delayed was the blood flow recovery. ConclusionsSince blood flow decreased after downfracture and recovered only to around 85.4% of baseline after 6 months in LⅠO, preserving blood vessels is important. Furthermore, the recovery rate was lower in patients who underwent anterior movement, and blood flow reduced more in patients with longer DFT, suggesting the importance of determining the direction and distance of movement preoperatively, and repositioning and fixing the maxilla as quickly as possible during surgery.

Novel Parameter in Pre-Surgical Orthodontic Preparation: A Retrospective Study on the Role of the Upper Incisor Position and a Morphological Evaluation of the Anterior Nasal Spine.

The position and inclination of the incisors play a crucial role in achieving optimal outcomes in orthodontic and orthognathic surgical treatment, given their impact on facial aesthetics. Background/objectives: Due to numerous distorting factors that affect the reliability of the ANB angle, the aim of the present work is to evaluate a more constant parameter over time, the anterior nasal spine (ANS), and explore whether aligning the incisal margin of the upper incisors with the anterior nasal spine could be a reliable indicator for achieving appropriate labial support in pre-surgical orthodontic preparation. Methods: From a pool of 500 cone beam computed tomography (CBCT) scans, 50 CBCT examinations displaying a Class 1 skeletal pattern (ANB = 2° ± 2°) with an intermediate (3.2-4 mm) or mixed (4-6 mm) sagittal maxillary position (MX), as determined by the 3D multiplanar total face approach (TFA), were selected and compared with CBCT examinations randomly chosen from the initial pool. Moreover, 12 landmarks were identified, and measurements were automatically obtained, using software, and recorded. Mean and standard deviation values were calculated for each sample. A comparison was made between the two samples, aligning the results with the morphological analysis of the anterior nasal spine and the sagittal position of the upper maxilla. Results: In Class 1 subjects, the distance between the incisal margin and the plane passed in relation to the anterior nasal spine should range between -1 mm and 1 mm, aligned with or slightly ahead of the anterior nasal spine or slightly ahead of this limit. Conclusions: The anterior nasal spine can serve as a reliable reference point for planning the position of the upper incisors, with excessive proclination or retroclination from this reference point deemed unacceptable.

Health-related quality of life, jaw function and sleep-disordered breathing among patients with dentofacial deformity.

Patients with dentofacial deformity (DFD) requiring orthognathic treatment have poor aesthetics, jaw function and psychological well-being, which potentially affect the quality of life. This study aimed to investigate the health-related general, oral and orthognathic quality of life, jaw function and sleep-disordered breathing at different stages of orthognathic surgical treatment. A total of 120 consecutive patients with DFD were recruited and grouped as pre-orthodontic treatment (group 1), pre-surgery (group 2), 4 months post-surgery (group 3), 24 months post-surgery (group 4) and in addition 30 controls without DFD (group 0). Outcomes were assessed using general health Short Form Survey (SF-36), Oral Health Impact (OHIP-14), Orthognathic Quality of Life Questionnaire (OQLQ), STOP-Bang and Jaw Function Limitation Scale (JFLS) questionnaires. In addition, presence or absence of pain was recorded. Data were tested with analysis of variance, Kruskal-Wallis test, Tukey post hoc test and structural equation modelling (SEM). Results revealed SF-36 (p = .814) and STOP-Bang (p = .143) total scores did not differ between control and treatment groups. In contrast, OHIP-14, OQLQ and JFLS total scores differed between groups (p = .001). Higher scores were observed in groups 1 (p = .001), 2 (p = .001) and 3 (p = .041) compared to group 0, indicating poor oral health in patients with DFD. Importantly, in group 4, oral health-related quality of life was better, and OHIP-14 (p = .936) and JFLS (p = .572) scores did not differ from controls. OQLQ scores of group 4 were significantly lower than group 1 (p = .001) but higher than group 0 (p = .013). SEM results revealed a significant negative associations of pain with JFLS and OQLQ; OHIP-14 with OQLQ; OHIP-14 with SF-36; and finally STOP-Bang with SF-36. Positive associations were observed between JFLS and OHIP-14; OHIP-14 and OQLQ. Oral health-related quality of life and jaw function appears to be improved 24 months after orthognathic surgery. Pain and limitation in jaw function had a negative association with health-related quality of life.

Placing the maxilla in the most aesthetic sagittal position: validation of several reference lines in relation to the forehead shape

The ideal sagittal position of the maxilla is highly subjective in orthognathic surgical treatment planning. There is no consensus on an analysis to predict the ideal sagittal position of the maxilla. The objective of this study was to determine the preferred maxillary position in relation to the forehead shape, in the Southern Chinese population. The maxilla position of eight patients was simulated based on Steiner’s analysis (SA), glabella vertical (GV), Andrews’ Element II (AE2), and the Barcelona reference (BR). The simulations were then used in an electronic survey, where respondents ranked the images for each patient from to 1–4 (most to least attractive). A total of 128 responses were collected from dental professionals and laypersons. The most preferred to the least preferred simulation was as follows (mean rank scores for the male and female patients in parenthesis): BR (males 2.06; females 1.98), GV (males 2.11; females 2.21), SA (males 2.59; females 2.40), and AE2 (males 3.24; females 3.41). There was no significant difference in the results according to the sex, age group, or profession of the respondents. The Barcelona reference and glabella vertical are useful in predicting the ideal maxillary position in patients with a flat forehead, and the Barcelona reference is the most preferred in patients with a rounded forehead.

Modification of surgical and positioning splint for orthognathic surgical treatment of facial asymmetry

Present short communication demonstrates innovative approach for surgical and positioning splint modification, which could improve accuracy of orthognathic surgery during facial asymmetry treatment. Usage of traditionally designed splint leads to the orientation of the midline based just on visual control, which inevitably associated with some level of maxilla deviation. It was proposed to design splint with mutually perpendicular planes in its’ frontal part at the specialized software. Such approach helps to align vertical plane of the splint with the midline vertical facial plane, while horizontal component could be aligned with the horizontal one accordingly. Proposed approach was approbated in five different clinical cases of facial asymmetry treated by orthognathic surgery. In all analyzed cases dental midline aligned perfectly with the planned one, in two cases the midline sagittal plane deviations (from ANS to PNS) resulted to be less than 2°. The horizontal occlusal plane deviations were considered clinically non-significant. Modification of the surgical splint for jaws positioning in orthognathic surgery treatment enables possibilities to check and control position of maxilla regarding reference facial planes intraoperatively, which in turn increases the accuracy of bone fragments placement and assure high precision of orthognathic surgery for asymmetric cases.

Multidisciplinary Planning in Orthognathic Surgery for Prosthetic Patients

The correction of malocclusions with severe skeletal deformity generally requires surgery combined with orthodontic or prosthodontic treatment; partially or totally edentulous patients, and patients with a prosthetic fixed crown, represent treatment restrictions and, therefore, challenges. The purpose of this study is to show a complete multidisciplinary approach and the planning involved (pre-, intra-, and post-operative) for a patient with a class-II or -III dento-skeletal malformation, who presents a total or partial edentulism or a fixed-type rehabilitation and, therefore, requires a combined orthognathic surgical treatment with prosthetic rehabilitation. Orthognathic surgery can be performed on an edentulous or prosthodontic patient to correct discrepancies between the jaws, followed by the placement of implants or a mobile prosthesis to rehabilitate the maxillary bones maxillary Different surgical approaches and technical variations have been proposed; however, the key to the success of such treatments lies in the multidisciplinary nature of the entire diagnostic, programmatic, and therapeutic path, which, therefore, necessitates close collaboration between different specialists—in particular, the maxillofacial surgeon, the orthodontist, and the prosthetist.

Do Patients Detect Changes in Breathing After Orthognathic Surgery?

Orthognathic surgery addresses facial aesthetics and function in patients with dentofacial deformities. It is associated with changes in upper airway volume (UAV). If changes in UAV are perceived by asymptomatic patients is unclear. The purpose was to measure associations between changes in UAV and patient-reported benefits using patient-reported outcome measures. A sample presenting dentofacial deformities without reported breathing problems undergoing orthognathic surgery was retrospectively studied. Patients aged 18-30years with 12-month follow-up were included. Patients with systemic disease, drug abuse, mental health disorder, or temporomandibular joint dysfunction were excluded. The predictor variable was changes in UAV measured in 3-dimensional computed tomography. Subjects were grouped into increased or decreased UAV. The primary outcome variable was changes in health-related quality of life measured with Oral Health Impact Profile 49 (OHIP-49). Weight, height, age, sex, and sub-scaled OHIP-49 were registered. Cephalometric measurements of hard tissue movements were recorded. Mean, standard deviation, and a level of statistical significance at P<.05 were used. Differences in OHIP-49 were compared using unpaired t-test. The correlation between covariates and outcomes was analyzed using the Spearman's rank test. Analysis of covariance between the predictor and outcome, adjusted for covariates (body mass index), was performed. Fifty-four subjects with a mean age of 20.89years and 52% males were enrolled. The mean change in UAV was 0.12cm3 (standard deviation [SD] 9.21, P=.93) with a mean absolute deviation of 7.28cm3 (SD 5.54). The mean change in OHIP-49 score was 20.93 (SD 28.90). Twenty-seven (50%) subjects had increased UAV (7.4cm3, SD 6.13) and the other had decreased (-7.17cm3, SD 5.01) (P=.01). At follow-up, equal levels of mean OHIP-49 score were found, but because of a baseline difference (15.74, P=.048), the subjects with and without increased UAV improved in OHIP-49 score 13.04 (SD 30.53) and 28.81 (SD 25.33), respectively (P=.04). Because equal levels of OHIP-49 score at follow-up, changes in UAV could not be associated with patient-reported health-related quality of life. Patient-reported outcome measure evaluations of orthognathic surgical treatment for airway obstruction should be performed in patients with a perceived impairment.

Associations between temporomandibular disorders, pain, jaw and masticatory function in dentofacial deformity patients: A cross-sectional study.

Patients with dentofacial deformity often present with impaired masticatory function, orofacial pain and temporomandibular disorders (TMD). This study investigates the relationship between TMD, pain, jaw and masticatory function at different stages of orthognathic surgical (OS) treatment. A total of 120 OS patients were prospectively recruited and grouped as pre-orthodontic (group 1), pre-surgery (group 2), 4-month post-surgery (group 3), 24-month post-surgery (group 4), in addition to 30 controls (group 0). Outcomes were assessed using: Jaw Function Limitation Scale (JFLS), McGill pain questionnaire, DC/TMD instrument, voluntary maximum bite force (MVBF), and masticatory efficiency (ME) using two-coloured chewing gum. Data were analysed using structural equation modelling. The prevalence of non-painful TMD did not differ between groups (p = .827). However, the prevalence of painful TMD differed between groups (p = .001). Among the painful TMDs, the highest prevalence was observed for masseter myalgia in group 2 (p = .031), and importantly group 4 did not differ from group 0 (p = .948). The MPQ score was significantly higher in group 1 (p = .001) compared to group 0, and the JFLS score was significantly higher in groups 1, 2 and 3 compared to group 0. Notably, MPQ (p = .756) and JFLS (p = .572) scores in group 4 were not different from group 0. However, MVBF (p = .996) and ME (p = .991) did not differ between groups 1 and 4. The association of self-reported pain and jaw function with the masticatory function was observed in OS patients. OS was not associated with a negative impact on TMD. Jaw function and pain levels were similar to controls at the 24-month follow-up. The masticatory function was further affected by the surgery and seems to require a longer recovery time. Moreover, it was confirmed that pain and TMD were associated with limitations in jaw function and impacts on masticatory function.

Impacts of Development, Dentofacial Disharmony, and Its Surgical Correction on Speech: A Narrative Review for Dental Professionals.

Speech is a communication method found only in humans that relies on precisely articulated sounds to encode and express thoughts. Anatomical differences in the maxilla, mandible, tooth position, and vocal tract affect tongue placement and broadly influence the patterns of airflow and resonance during speech production. Alterations in these structures can create perceptual distortions in speech known as speech sound disorders (SSDs). As craniofacial development occurs, the vocal tract, jaws, and teeth change in parallel with stages of speech development, from babbling to adult phonation. Alterations from a normal Class 1 dental and skeletal relationship can impact speech. Dentofacial disharmony (DFD) patients have jaw disproportions, with a high prevalence of SSDs, where the severity of malocclusion correlates with the degree of speech distortion. DFD patients often seek orthodontic and orthognathic surgical treatment, but there is limited familiarity among dental providers on the impacts of malocclusion and its correction on speech. We sought to review the interplay between craniofacial and speech development and the impacts of orthodontic and surgical treatment on speech. Shared knowledge can facilitate collaborations between dental specialists and speech pathologists for the proper diagnosis, referral, and treatment of DFD patients with speech pathologies.

Evaluate the long-term hard tissue stability and relapse factors following surgical–orthodontic treatment

Background and aim: the present study was conducted with the aim of evaluating the long-term hard tissue stability and relapse factors following surgical-orthodontic treatment. Method: Databases of PubMed, Scopus, Web of Science, EBSCO, ISI Web of knowledge and Embase were searched for systematic literature until July 2022. 95% confidence interval for mean differences with fixed effect model and Inverse-variance method were calculated. To deal with potential heterogeneity, random effects were used and I2 showed heterogeneity. Meta-analysis was performed using Stata/MP v.17 software. Result: In the initial review, duplicate studies were eliminated and abstracts of 201 studies were reviewed, the full text of 38 studies was reviewed by two authors, finally, ten studies were selected. Overbite changes, Upper incisor changes and Lower incisor changes after combined orthodontic and orthognathic surgical treatment in class II and III patients during long-term follow-up was 1.80 (MD 95% CI; 1.43 and 2.17), -0.51 (MD 95% CI; -1.08 and 0.05) and 0.27 (MD 95% CI; 1.03 and 1.58), respectively. Conclusion: Based on the findings of the present study, in patients with skeletal class II and III, the results of long-term dental changes after combined orthodontic and orthognathic surgery are very diverse.

Bimaxillary Distalization with Skeletal Anchorage for Management of Severe Skeletal Class III Open Bite Malocclusion.

Adult patients with severe vertical growth pattern, skeletal class III malocclusion and open bite anteriorly are difficult orthodontic cases to treat. An orthognathic surgical treatment plan may benefit adult patients with such types of complex malocclusions, however in certain cases, the patient's medical history may contraindicate the surgical treatment plan. A male patient aged 17 years presented with a prognathic mandible, Angle's class III malocclusion on a class III skeletal base with proclination in upper incisors, retroclination of lower incisors, and reduced facial convexity. Patient gave history of asthma and complex cardiac diseases including arrhythmia, irregular heartbeat, and pacemaker. This case report describes a non-surgical approach of distalization of mandibular and maxillary arches performed with the help of miniplates to achieve an improvement in the facial balance without surgery.

Reasons for refusing orthognathic surgery by orthodontic patients: A cross-sectional survey.

To find out the most common reasons for refusing orthognathic surgery and to compare the responses along gender lines and in terms of open-ended and closed-ended approaches. The cross-sectional retrospective study was conducted from August to December 2020 at the Orthodontics Department of Bahria University Medical and Dental College, Karachi, Pakistan, and comprised of patients who were planned for but refused orthognathic surgical treatment between January 2018 and July 2020. Data was collected through telephone-based interviews to record reasons of avoiding orthognathic surgery. The data-collection tool had both open-ended and closed-ended questions. Data was analysed using SPSS 23. Of the 60 patients, 42(70%) were females and 18(30%) were males with a mean age range of 23.25±2.19years. Overall, 19(31.7%) patients avoided surgery due to additional expense, while post-operative pain was cited as a reason by 35(58.3%) patients. Males were 9 times more concerned about their dental alignment compared to females (p=0.005). Fear of tooth injury (p<0.0001) and intra-operation and post-operation bleeding (p<0.0001) were found twice in males than females. The most common reasons for refusal to have orthognathic surgery were increased cost and post-operative pain. Males were more concerned about dental alignment and had higher fear of post-surgical tooth injury and intra- and post-operative bleeding compared to the females.

Deep convolutional neural network-based automated segmentation and classification of teeth with orthodontic brackets on cone-beam computed-tomographic images: a validation study.

Tooth segmentation and classification from cone-beam computed tomography (CBCT) is a prerequisite for diagnosis and treatment planning in the majority of digital dental workflows. However, an accurate and efficient segmentation of teeth in the presence of metal artefacts still remains a challenge. Therefore, the following study aimed to validate an automated deep convolutional neural network (CNN)-based tool for the segmentation and classification of teeth with orthodontic brackets on CBCT images. A total of 215 CBCT scans (1780 teeth) were retrospectively collected, consisting of pre- and post-operative images of the patients who underwent combined orthodontic and orthognathic surgical treatment. All the scans were acquired with NewTom CBCT device. A complete dentition with orthodontic brackets and high-quality images were included. The dataset were randomly divided into three subsets with random allocation of all 32 tooth classes: training set (140 CBCT scans-400 teeth), validation set (35 CBCT scans-100 teeth), and test set (pre-operative: 25, post-operative: 15 = 40 CBCT scans-1280 teeth). A multiclass CNN-based tool was developed and its performance was assessed for automated segmentation and classification of teeth with brackets by comparison with a ground truth. The CNN model took 13.7 ± 1.2 s for the segmentation and classification of all the teeth on a single CBCT image. Overall, the segmentation performance was excellent with a high intersection over union (IoU) of 0.99. Anterior teeth showed a significantly lower IoU (P < 0.05) compared to premolar and molar teeth. The dice similarity coefficient score of anterior (0.99 ± 0.02) and premolar teeth (0.99 ± 0.10) in the pre-operative group was comparable to the post-operative group. The classification of teeth to the correct 32 classes had a high recall rate (99.9%) and precision (99%). The proposed CNN model outperformed other state-of-the-art algorithms in terms of accuracy and efficiency. It could act as a viable alternative for automatic segmentation and classification of teeth with brackets. The proposed method could simplify the existing digital workflows of orthodontics, orthognathic surgery, restorative dentistry, and dental implantology by offering an accurate and efficient automated segmentation approach to clinicians, hence further enhancing the treatment predictability and outcomes.

Prospective Comparison of Facial Soft Tissue Changes Using 2D Photographs and 3D Scanning After En Masse Dentoalveolar Maxillary Distalization Using Tads

Introduction: This prospective clinical study was undertaken to analyse the three-dimensional facial soft tissue changes after en-masse maxillary distalization using 3D structured light-based scanner and facial photographs and to compare the two diagnostic aids. Materials and Method: 12 Indian adult patients of 17- 23 years of age with unilateral or bilateral class II molar relationship and those indicated for en-masse distalization. A pre-operative and post-operative extra oral 3D scan and 2D photographs were obtained for each subject. A prospective comparative evaluation of 10 lateral and 20 frontal soft tissue parameters was done. Result: When pre to post comparison was made in different study parameters using paired t test, none of the study parameter showed significant difference. Conclusion: The laser facial scanning can be considered as a useful and reliable tool to analyze the circumoral region for orthodontic and orthognathic surgical diagnosis and treatment planning. The difference in facial soft tissue changes evaluated using 3D scans and 2D photographs was also not statistically significant.

Treatment of Anterior Crossbite with Skeletal Class III Malocclusion during the Growth Period

Anterior crossbite is the most common problem in Angle class III malocclusion and is aesthetically disturbing. As individuals get older, an anterior crossbite can worsen, impacting the esthetics of the face and the stomatognathic system’s function significantly and requiring immediate treatment. Due to genetics, habitual postures, ethnicity, and environmental variables, the class III malocclusion’s etiology is multifaceted. In terms of treatment, there are three options: growth modification, camouflage, and orthognathic surgical treatment. This case report aims to describe a non-surgical treatment with simple treatment mechanics in two patients who were still in their growth period. Two patients, a sibling aged 14 and 13 years, experienced an anterior crossbite with a deep overbite, diagnosed with Angle class III with skeletal class III relationships. Besides, the profile revealed a concave, with an overjet of -2mm and an overbite of 4mm. The treatments were then performed employing fixed orthodontic appliances with vertical U-loops for protraction of upper anterior teeth and class III intermaxillary elastics to correct molar relationships. The treatment was completed in two years, in which the anterior crossbite was corrected. The molar and canine relationships, which were originally class III, became class I. Loss of tooth 36 was closed, and tooth 38 has fully erupted. Treatment of anterior crossbite needed to be done as soon as possible to prevent more severe abnormalities. In conclusion, a treatment in the growth period with simple techniques resulted in significant improvements in function and aesthetics.

Four-dimensional visualization of mandibular movement in the Class III patient before and after combined orthodontic and orthognathic treatment

To analyze the results of jaw motion before and after combined orthodontic and orthognathic surgical treatment in the Class III patient. A 33-year-old male with Class III malocclusion (ANB -2°, Wits -3 mm) was referred for facial deformity and malocclusion. After orthodontic preparation, a bimaxillary mandibular first orthognathic surgery was performed. After bilateral sagittal split osteotomy (BSSO) the lower jaw was shifted on the right for 3 mm right and was cw rotated for 4 mm. Le Fort I osteotomy with segmentation was performed to move the maxilla forward for 6 mm and cw rotate for 4 mm. Four-dimensional visualization of the mandibular movement was made using Planmeca 4D jaw motion system. The valuable quantitative data regarding lower jaw movement and measurement information were exported and analyzed. The maximum aperture during opening-closing movement differ before (38.7 mm) and after surgery (32.1 mm) for 6.6 mm. After surgery horizontal displacement in the maximum left lateral excursion increased by 7.6 mm and in the maximum right lateral side by 4.6 mm. Protrusion increased by 0.9 mm after surgery. Combined orthodontic and orthognathic treatment can improve soft tissue, skeletal, dental relationship, and functional results.

Current Trends in Skeletal Borderline Patients: Surgical versus Orthodontic Treatment Decisions—What Is the Evidence?

Background: The aim is to assess the current evidence-based knowledge about treatment decisions for skeletal malocclusion in adult borderline patients. Methods: A literature search was conducted through three databases. Inclusion criteria were restricted to systematic reviews, prospective, retrospective, and control studies. Only articles comparing orthodontic camouflage and orthognathic surgical treatment for Class II and Class III malocclusions in adult patients were selected to be reviewed. Results: Seven articles concerning Class II and nine concerning Class III met the inclusion criteria. Scientific evidence was poor due to low methodological quality. Conclusions: Surgical treatment was found to better improve skeletal and soft-tissue cephalometric values, whereas camouflage treatment mainly involved dentoalveolar movements. Aesthetic changes, as perceived by the patient, were not significantly different in the two groups. Recently improved surgical techniques, differing from those described in the analyzed articles, may provide similar or more stable outcomes compared with orthodontic-only treatment. Although some cephalometric variables can be helpful, the most important parameters for treatment selection are the patient’s presenting complaint and their self-image perception. Further studies with larger sample sizes and similar pretreatment conditions, and considering patient self-evaluation of esthetics and function, should be undertaken.

Evaluation of pre- and post-treatment masticatory and bite force efficiency in patients undergoing fixed orthodontic treatment and orthognathic surgery using T-Scan Novus occlusal analysis: A factorial randomized controlled trial.

Orthodontic and orthognathic surgical treatment require quantified occlusion finish to rule out any temporomandibular disorders. Hence, the present study was proposed to analyze the occlusal efficiency in patients undergoing fixed orthodontic and combined orthodontic-orthognathic surgery using digital occlusal analysis. A randomized multi-arm controlled trial was conducted on 55 patients divided into four groups, that is, group I: class I crowding/proclination required extraction for fixed orthodontic treatment, group II: class II div 1 required orthodontic treatment and/or myofunctional therapy, group III: skeletal class II required combined orthodontic and orthognathic surgical treatment, and group IV: skeletal class III required combined orthodontic and orthognathic surgical treatment. The pre-treatment, before debonding, and 1 year after debonding assessment of occlusion were carried out using T-Scan. The repeated analysis of variance (rANOVA) test along with post-hoc analysis was carried out for intra-group and inter-group assessments using SPSS (version 21, USA). The significance level was set at a 'P' value less than 0.05. rANOVA measurement in groups I, II, and III showed a significant difference with respect to maximum bite force difference between right and left sides, anterior and posterior region, and left lateral disclusion time. However, group IV showed a significant difference with respect to maximum bite force in the anterior and posterior region as well as right and left lateral disclusion time only. Further application of the post-hoc Tukey test found a significant difference between the To value to T1 and T2 among all four groups. Improved bite force was found in all malocclusion groups which was gradual in improvement from pre-treatment to post-treatment and a subsequent retention phase. The study also reported the utility of digital occlusal assessment devices as reliable, repeatable, reproducible, and user-friendly in the determination of dynamic occlusion.

Cephalometric norms for the north Indian population: A systematic review.

The cephalometric norms for orthognathic surgery (COGS analysis) are the standard benchmark in cephalometrics for any orthognathic surgical diagnosis and treatment planning. Since the introduction of cephalometrics by Broadbent, numerous studies have been conducted to establish craniofacial norms of different ethnicities. Most of these studies, however, determined craniofacial norms for Caucasian people and may not be applicable to other ethnic groups due to differences in their facial appearance. Therefore, it is essential to study and compare the existing cephalometric parameters between Caucasians and Indians to validate their application during the treatment planning of the orthognathic surgery. This review focuses on studying the cephalometric norms for the North Indian (NI) population and establishing the COGS analysis for the population of North India. The objective is to determine the cephalometric parameters of Angle's dental and skeletal Class I faces for the NI population. The following databases were searched for the present study -PubMed, Ovid MEDLINE, and EMBASE. The initial inclusion criteria comprised studies written in English and quoting cephalometric norms in Indian population. The time period of publications was not determined. The quality features evaluated were sample description, variables analyzed, and how cephalometric standards were evaluated. Initially, 49 articles were retrieved. After removal of the duplicated records and assessing for the eligibility, four articles met the inclusion criteria. These four articles were included in the systematic review. The NI people are characterized by having small cranial base, short facial height, protrusive chin, and more inclination of mandibular incisors in comparison with Caucasians. Due to limited research on the Central Indian cephalometric norms, the Caucasian norms are still referred for the diagnosis and treatment planning of orthognathic surgery for NI population.