Occlusal Changes Research Articles

Vision-based target point tracking and aiming method

PurposeLaser absolute distance measurement has the characteristics of high precision, wide range and non-contact. In laser ranging system, tracking and aiming measurement point is the precondition of automatic measurement. To solve this problem, this paper aims to propose a novel method.Design/methodology/approachFor the central point of the hollow angle coupled mirror, this paper proposes a method based on correlation filtering and ellipse fitting. For non-cooperative target points, this paper proposes an extraction method based on correlation filtering and feature matching. Finally, a visual tracking and aiming system was constructed by combining the two-axis turntable, and experiments were carried out.FindingsThe target tracking algorithm has an accuracy of 91.15% and a speed of 19.5 frames per second. The algorithm can adapt to the change of target scale and short-term occlusion. The mean error and standard deviation of the center point extraction of the hollow Angle coupling mirror are 0.20 and 0.09 mm. The mean error and standard deviation of feature points matching for non-cooperative target were 0.06 mm and 0.16 mm. The visual tracking and aiming system can track a target running at a speed of 0.7 m/s, aiming error mean is 1.74 pixels and standard deviation is 0.67 pixel.Originality/valueThe results show that this method can achieve fast and high precision target tracking and aiming and has great application value in laser ranging.

Occlusal changes in orthodontically treated subjects 40 years after treatment and comparison with untreated control subjects

The objective of this study was to compare the aging changes of the dental arches in orthodontically treated and untreated subjects after a 4-decade follow-up period. This retrospective study analyzed 2 groups. The treated group comprised 29 patients (11 male, 18 female) presenting with Class I or Class II malocclusions orthodontically treated with extractions of 4 first premolars. Dental models taken at pretreatment (12.84years), posttreatment (14.95years), and long-term posttreatment (51.37years) were evaluated. The untreated (control) group consisted of 22 untreated patients with dental models taken at 13.32, 17.82, and 60.95years of age. The dental models were digitized, and the following variables were evaluated: Little irregularity index, intercanine, interpremolar and intermolar widths, arch length, arch perimeter, overjet, and overbite. Interphase comparison of the treated group was performed with repeated measures analysis of variance and Tukey tests. Intergroup comparisons were performed using t tests (P<0.05). Crowding was corrected with treatment but relapsed significantly in the long term. Intercanine width increased with treatment and decreased in the long term. Interpremolar and intermolar widths, arch perimeter, and length decreased with treatment and continued to decrease long-term posttreatment. Overjet and overbite were corrected with treatment and remained stable in the long term. From posttreatment to long-term posttreatment, a greater crowding increase was observed in the treated group than in the untreated group. The treated group demonstrated a greater decrease in mandibular intercanine and maxillary and mandibular interpremolar widths than the untreated sample. Overbite increased in the treated group and decreased in the untreated group. The multiple regression analysis showed that previous 4-premolar extractions orthodontic treatment is significantly associated with anterior crowding in the long term. In the long-term, the treated patients showed relapse of crowding and a decrease in arch form. Long-term changes of treated patients were different from untreated subjects. Relapse might have contributed to greater changes in incisor crowding and arch widths observed in the treated patients.

Occlusal disharmony and chronic oro-facial pain: from clinical observation to animal study.

Occlusion can be viewed as the most sensitive susceptor of the central nervous system in the oro-facial region. Its inalienable relationships to the temporomandibular joint, the muscles, the stomatognathic system and even the central nervous system are self-evident. Almost all the dental treatments inevitably change the occlusion, potentially or actually, locally or extensively, and immediately or gradually. The objective of this study was to present a narrative literature on occlusal disharmony and chronic oro-facial pain. Literature reviews focusing on clinical studies about the relationship between occlusal disharmony and myofascial oro-facial pain, and related preclinical studies about the animal models of, as well as the peripheral and central mechanisms underlying this condition related to, occlusal disharmony were used as starting point and guidelines to describe the topics mentioned. A search of the PubMed database was performed mainly with the following search terms: "occlusion," "occlusal interference," "occlusal disharmony," "occlusal change," "oro-facial pain" and "myofascial pain." Relevant literature from the past 70 years until the present day was meticulously studied. The literature review together with three related characteristic clinical cases revealed an intimate association between occlusal disharmony and chronic oro-facial pain, involving pathological changes, extending from the peripheral tissues to the central nervous system. The patients suffered from psychological distress, sleep disturbance and poor life quality. Occlusal disharmony-related oro-facial pain is a clinical problem that deserves attention, although there are no universally accepted clinical protocols. The existing literature provides some constructive suggestions, but further research is needed.

Evaluation of the three-dimensional (3D) position of cervical vertebrae in individuals with unilateral posterior crossbite.

To evaluate the three-dimensional (3D) position of the cervical vertebrae of growing subjects with unilateral posterior crossbite (UPC). In this cross-sectional study, cone beam computed tomography (CBCT) scans of 1455 patients were screened, and ultimately 58 scans (26 patients with UPC and 32 controls with normal occlusion) were included after imposing inclusion/exclusion criteria. Roll, yaw, and deviation of the geometric center of C1, C2, and C3 vertebrae were measured and compared between groups. A correlation between these parameters and different variables on mandibular positioning was also carried out. A statistically significant difference (p < 0.05) was observed between groups for the deviation of pogonium (Pog), mandibular plane roll, and C3 roll, and patients with UPC showed higher cant or deviation. A significant correlation was reported for the roll of C2 and C3 with the deviation of Pog, a roll of the occlusal plane, and roll of the mandibular plane (p < 0.05). The greater the deviation of the Pog to one side, the greater the roll of the vertebrae with this same side up. The same tendency was observed between the roll of the occlusal plane or the mandibular plane with the roll of these cervical vertebrae. There is a positive correlation between transverse occlusal changes and positional deviations of the cervical vertebrae, especially C2 and C3. The study results do not allow us to infer the clinical/functional consequences of these deviations, as well as if malocclusion's treatment would result in an improvement of intervertebral relationships.

THE ROLE OF MAGNETIC RESONANCE RESEARCH IN THE TREATMENT OF DYSFUNCTION OF THE TEMPOROMANDIBULAR JOINT

The main criterion for diagnosis of dysfunctional conditions of the temporomandibular joint is the visualization of the intra-articular cartilaginous disc. The method of diagnosis, that the most perfectly determines the disorders in the temporomandibular joint, particular the displacement of the menisci, is magnetic resonance imaging. So, the aim of the work was to determine the amplitude of anterior displacements of the menisci in patients suffering from dysfunction of the temporomandibular joint using magnetic resonance imaging.&#x0D; In 20 patients, who underwent magnetic resonance imaging, different amplitudes of the anterior displacements of the meniscus were determined. Patients were divided into groups. The first group included 6 patients who were diagnosed by MRI the anterior displacement of the disc to the center of the articular head. The second group included 4 patients who had anterior displacement of the disc to the center of the articular head by 2/3 of its own length. Ten patients of the third group had a displacement of the meniscus to the center of the articular head by 1/2 of its own length. For the future treatment of TMJ dysfunction, the distance of the pathological displacement of the meniscus determines the degree of occlusion. All patients were prescribed a Michigan-splint occlusal splint in combination with a sling-like head cap at night. The results of the selected treatment were interpreted after 3-6 months.&#x0D; A series of magnetic resonance imaging has described the articular fissures of the temporomandibular joint, articular discs (their shape in frontal projection and on parasagittal sections), posterior ligaments, and lateral pterygoid muscles. Each of the joints was carefully examined in the case when the mouth is closed and open. During the MRI description, the shape of the joint heads and their possible pathological changes were determined. In the position of the closed or open mouth, the positions of each of the discs and their poles relatively to the articular head in centimeters were compared, and the movement of the menisci was described. The sizes of disks of the closed and open mouth were defined. The study protocol also reported the shape and amplitude of the movements of the articular heads.&#x0D; Treatment was planned according to the selected protocol. For the first group of patients diagnosed with anterior meniscus dislocation, treatment was planned by separating the occlusion to the relatively physiological rest of the mandible (2 - 4 mm). The patients of the second group, in which anterior displacements of the disc relatively to the articular head by 2/3, were treated with detachment of the occlusion to contact with the cutting edge of the teeth of the upper and lower jaws. For the third patients’ group with diagnosed anterior displacement of the meniscus by 1/2, treatment was performed with a separation of the bite on 2 - 4 mm above the contact with the cutting edges of the front teeth. The main criterion for recovery is the complete disappearance of symptoms of dysfunction, even without the use of a splint.&#x0D; At the first stage of treatment the task was the following: reconstruction of a myotatic reflex by means of the medical and diagnostic occlusal splint "Michigan-splint" completed with the main slingshot cap. Patients were monitored monthly. The main problems were the following: after a week of using the structure the patients complained of increased salivation, muscle pain and burning, headache, which disappeared after approximately 3 weeks. The main cause of such phenomena is the physiological rearrangement of the muscular reflex, which involves a certain tension in the muscles and irritation of the nerve endings in the muscles due to changes in the usual occlusion. During planned examination, the patients demonstrated supercontacts followed by cap correction. In 3 or 6 months of using the Michigan-splint occlusal splint, patients noted a significant improvement and they didn’t have any complaints. The main criterion for recovery is the complete disappearance of symptoms of dysfunction, even without the use of a splint. Therefore, the next stage of treatment depended on the anatomical and functional changes of TMJ and consolidation of therapeutic effect was been necessary.&#x0D; Therefore, the use of magnetic resonance imaging of the temporomandibular joint to determine the amplitude of the displacements of the discs, ensures the effectiveness of the selected treatment.&#x0D; Prospects for further research include improvement of the MRI protocol and its correlation with definite symptoms, the distance of the vertical separation of occlusal surfaces, and the introduction of the protocol into practical health care.

Mechanical and behavioral approaches to orthodontic retention: A best-evidence review

• Introduces the concept of retainability of occlusal features and provisional hierarchy of stability. • Considers the evidence underpinning a range of approaches to enhancing long-term stability, including behavioral and mechanical interventions. • Highlights the need for further refinement of mechanical techniques coupled with an emphasis on novel behavioral approaches Orthodontic retention has seen significant refinement in recent years with an increasing focus on developing removable retainers offering improved adaptation, comfort and longevity. Similarly, fixed retention has not been immune to change, with a range of new approaches coming into common usage. Notwithstanding this, a purely mechanical approach to retention is insufficient; patient understanding, behaviors, and commitment are critical to optimal outcomes. On the basis of high-quality clinical trials, there is convincing evidence of equivalence between fixed and removable approaches in the short term. However, some level of deterioration is known to occur on the basis of long-term evaluation irrespective of the mechanical approach used. Therefore, the final frontier in orthodontic retention may reside in developing holistic mechanical and behavioral approaches to meet the challenge of mitigating the tendency for negative occlusal change in the longer term.

Strong-Weak Feature Alignment for 3D Object Detection

Object detection in 3D point clouds is still a challenging task in autonomous driving. Due to the inherent occlusion and density changes of the point cloud, the data distribution of the same object will change dramatically. Especially, the incomplete data with sparsity or occlusion can not represent the complete characteristics of the object. In this paper, we proposed a novel strong–weak feature alignment algorithm between complete and incomplete objects for 3D object detection, which explores the correlations within the data. It is an end-to-end adaptive network that does not require additional data and can be easily applied to other object detection networks. Through a complete object feature extractor, we achieve a robust feature representation of the object. It serves as a guarding feature to help the incomplete object feature generator to generate effective features. The strong–weak feature alignment algorithm reduces the gap between different states of the same object and enhances the ability to represent the incomplete object. The proposed adaptation framework is validated on the KITTI object benchmark and gets about 6% improvement in detection average precision on 3D moderate difficulty compared to the basic model. The results show that our adaptation method improves the detection performance of incomplete 3D objects.

Long-term periodontal changes associated with oral appliance treatment of obstructive sleep apnea.

To characterize the mandibular anterior teeth crown height as a marker of periodontal changes and bone loss as a side effect of an oral appliance worn for a minimum of 4.5 years. This retrospective study conducted in patients with healthy baseline periodontium recruited participants among consecutive sleep apnea patients treated with an oral appliance between 2004 to 2014. Eligible participants were recalled for a follow-up visit at which a periodontal examination was performed and a lateral cephalogram and dental impressions were obtained. Clinical crown height for mandibular anterior teeth and cephalometric variables were measured and compared before and after treatment. A full periodontal evaluation was performed at the follow-up visit. Twenty-one patients enrolled with a mean treatment length of 7.9 ± 3.3 years. For the mandibular anterior teeth, clinical crown height did not change over the evaluated period. At follow-up, all the periodontal assessed variables were within normal limits, with the mean probing depth of 1.4 ± 0.5 mm, recession 0.6 ± 1.1 mm, and clinical attachment loss 0.8 ± 1.0 mm. Compared with baseline, there was a significant proclination of mandibular incisors (mean increase of 5.1 degrees) with the continued use of an oral appliance. Gingival levels were maintained with clinically insignificant changes during the observation period. Inclination of the mandibular incisors increases significantly with the use of an oral appliance in patients with obstructive sleep apnea. Positional changes in these teeth were not associated with any measured evidence of increase in clinical crown height or gingival recession. Heda P, Alalola B, Almeida FR, Kim H, Peres BU, Pliska BT. Long-term periodontal changes associated with oral appliance treatment of obstructive sleep apnea. J Clin Sleep Med. 2021;17(10):2067-2074.

Kegunaan radiografi panoramik pada masa mixed dentition

Objectives: The purpose of this review is to determine the usefulness of panoramic radiography during mixed dentition and also to capture panoramic radiographs during mixed dentition.&#x0D; Review: Mixed dentition is a period of mixed dentition and a period of transition from sequential deciduous teeth followed by the eruption of the replacement tooth, namely the permanent tooth. The mixed dental phase occurs in children aged 6-12 years, beginning with the eruption of the first permanent tooth, usually a central incisor or mandibular first molar. Changes in occlusion occur significantly during this time due to the loss of the deciduous teeth and the eruption of the replacement permanent teeth.&#x0D; Conclusion: The mixed dentition period can be classified into 3 phases, namely. (1) the first transitional period, occurs at 6-8 years of age. In this phase, the eruption of the permanent first molars and the replacement of the deciduous incisors with the permanent incisors occurred. (2) the inter-transitional period, after the first molars and permanent incisors erupt, there is a transient period of about 1-2 years before the second transition phase begins. In this phase, it is called inter-transitional because the maxillary and mandibular arches consist of deciduous and permanent teeth. In the inter-transitional phase it is relatively stable and no changes occur. (3) the second transitional period at age (10-13 years), the date of the mandibular canine at about 10 years of age usually begins the second transitional period.

CT perfusion based ASPECTS improves the diagnostic performance of early ischemic changes in large vessel occlusion

BackgroundASPECTS scoring method varies, but which one is most suitable for predicting the prognosis still unclear. We aimed to evaluate the diagnostic performance of Automated (Auto)-, noncontrast CT (NCCT)- and CT perfusion (CTP) -ASPECTS for early ischemic changes (EICs) in acute ischemic stroke patients with large vessel occlusion (LVO) and to explore which scoring method is most suitable for predicting the clinical outcome.MethodsEighty-one patients with anterior circulation LVO were retrospectively enrolled and grouped as having a good (0–2) or poor (3–6) clinical outcome using a 90-day modified Rankin Scale score. Clinical characteristics and perfusion parameters were compared between the patients with good and poor outcomes. Differences in scores obtained with the three scoring methods were assessed. Diagnosis performance and receiver operating characteristic (ROC) curves were used to evaluate the value of the three ordinal or dichotomized ASPECTS methods for predicting the clinical outcome.ResultsSixty-three patients were finally included, with 36 (57.1%) patients having good clinical outcome. Significant differences were observed in the ordinal or dichotomized Auto-, NCCT- and CTP-ASPECTS between the patients with good and poor clinical outcomes (all p < 0.01). The areas under the curves (AUCs) of the ordinal and dichotomized CTP-ASPECTS were higher than that of the other two methods (all p < 0.01), but the AUCs of the Auto-ASPECTS was similar to that of the NCCT-ASPECTS (p > 0.05).ConclusionsThe CTP-ASPECTS is superior to the Auto- and NCCT-ASPECTS in detecting EICs in LVO. CTP-ASPECTS with a cutoff value of 6 is a good predictor of the clinical outcome at 90-day follow-up.

Short term effects of interceptive expansion treatment: a prospective study.

This prospective cohort study investigated the short term effects of interceptive orthodontic treatment with a removable expansion plate, evaluating the changes in occlusion in all its dimensions: transversal, sagittal and vertical. A total of 226 patients treated with a removable expansion plate (slow maxillary expansion, SME) by orthodontic residents at the Department of Orthodontics, University Hospitals Leuven, Belgium were included. The patients had a mean age of 8.5 years at the start of the treatment. The mean treatment time was 6.9 months. Transversal measurements (intercanine and intermolar width) and occlusal characteristics (molar occlusion, overjet, overbite and functional shift) were collected before (T0) and after active treatment (T1). Statistical analysis was performed using the Wilcoxon signed rank test, Sign test and McNemar test for assessing changes between T0 and T1. Linear models were used to assess the associations between patient factors and the amount of expansion. A significant increase in transversal width at different occlusal landmarks was found. Correction of unilateral, bilateral and frontal crossbites was successful in 99.0%, 95.2% and 93.6% of the cases respectively. Changes in sagittal molar occlusion were significant: 64.9% (right side) and 62.6% (left side) remained stable, 28.4% (right) and 29.3% (left) improved and 6.7% (right) and 8.1% (left) deteriorated. Overbite changes were found to be statistically significant, though clinically irrelevant. Overjet changes were non-significant. A removable expansion plate is successful in improving the transversal dental dimensions of the maxilla. Statistically significant sagittal effects on molar occlusion were found. Long-term follow-up is needed to evaluate the long-term stability of this treatment.

Occlusal Disorders in Patients with Sickle Cell Disease: Critical Literature Review.

To identify the association of occlusal disorders in patients with sickle cell disease (SCD). A literature review was conducted, and articles published between 2010 and 2019 were searched on Bireme and PubMed websites and in MEDLINE and LILACS databases, in English, Portuguese, and Spanish, using the keywords "malocclusion," "sickle cell disease," and "cephalometry," combined by Boolean operators AND and OR. One of the criteria for the selection of articles was the presence of adolescents in the sample. This methodology followed the PRISMA recommendations. Seventy-nine articles were found, seven of which were included in the review as they met the inclusion criteria and the study goals. The prevalence of malocclusion in SCD patients ranged from 62.9% to 100%, which was considered very severe in 30.1% to 80.6%. The most common occlusal changes were Angle's class II malocclusion, increased maxillary overjet, and anterior open bite. In addition, class II skeletal pattern was the most prevalent due to mandibular retrusion. Malocclusion prevalence in SCD patients is high and considered to be a risk factor, with a significant rate of very severe malocclusion when compared to healthy patients.

Does the Stomatognathic System Adapt to Changes in Occlusion? Best Evidence Consensus Statement.

The purpose of this Best Evidence Consensus Statement was to evaluate the existing literature on the stomatognathic system's ability to adapt to occlusal changes. The search term stomatognathic system was not useful as it resulted in over 400,000 results nor was the search term temporomandibular joint adaptation with 738 results due to the large number of references not related to the topic. The terms stomatognathic system adaptation to occlusal changes (186 results), teeth flexion (139 results), muscle adaptation to dental occlusion (278 results), and occlusal changes and neuroplasticity (11 results) provided the best selection of articles related to the topic. Limiting the above searches to systematic reviews and randomized controlled clinical trials resulted in multiple publications that were related to the question.9-13 Other literature reviews, data-based publications, and expert opinion resources have been included due to their relationship to the question. From the extensive list of search results, 242 articles were determined to be potentially related to the focus question and were evaluated with 56 being included in this paper. It was determined that the stomatognathic system adapts to occlusal changes through the temporomandibular joint, muscles, teeth and bone. The dynamically modified periosteum on the articulator surfaces of the condyle and fossa has a unique load-bearing morphology with 3 subarticular layers of fibrocartilage that absorb and dissipate both peak (impact) and sustained loads. Adaptability of the TMJs and muscles can be documented through studies where artificially produced occlusal interferences were placed in patients and those study participants with normal temporomandibular joints (TMJs) adapted fairly well whereas those with a previous history of temporomandibular disorders (TMD) did not adapt as well. Available evidence indicates patients generally adapt to the occlusal change inherent in orthodontic treatment, mandibular advancement surgery, and the use of mandibular advancement devices. The head and neck muscles also adapt to occlusal changes in patients without a history of TMD. The dentition adapts to changes through the bone and periodontal ligaments as well as the ability of teeth to undergo slight flexion under masticatory loading. This article is protected by copyright. All rights reserved.

Comparative assessment of changes in pharyngeal airway space in cases of obstructive sleep apnoea with a customized mandibular repositioning appliance - a clinical study

ObjectivesThe present study aims at evaluating the effects of a customized mandibular repositioning appliance on the pharyngeal airway, nocturnal sleep patterns, daytime discomfort and occlusal changes in established cases of adult obstructive sleep apnoea.Material and MethodsTen consecutive patients with a complaint of snoring and disturbed sleep were included in the study. The primary diagnosis was established by the Epworth sleepiness scale, clinical examination, history and subsequently the diagnosis was substantiated through assessment of the pharyngeal airway space on a lateral cephalogram and polysomnography. A customized mandibular repositioning appliance was used to advance the mandible sequentially every 6 months, using 4 sets of the appliance. Pre and post-treatment evaluations were performed to establish, effects and changes in the outcome of obstructive sleep apnoea.ResultsThe study revealed significant increase in the mean pharyngeal widths of upper airway and velum dimension with antero-superior repositioning of hyoid bone. Epworth sleepiness scale score improved significantly from baseline with clinically evident change in daytime discomforts. Significant decline in the mean apnoea/hypopnea index, oxygen desaturation index, respiratory disturbance index, heart rate, snoring and a significant increase in mean oxygen saturation of arterial blood was observed. No evident change noticed in occlusion except lower incisor inclination.ConclusionThe customized mandibular repositioning appliances are effective in the management of adult obstructive sleep apnoea with a significant improvement observed in the airway patency and polysomnography parameters with clinically non-significant effects on dental occlusion..

Neurite Orientation Dispersion and Density Imaging of Rat Brain Microstructural Changes due to Middle Cerebral Artery Occlusion at a 3T MRI.

The purpose of this work was to demonstrate the feasibility of neurite orientation dispersion and density imaging (NODDI) in characterizing the brain tissue microstructural changes of middle cerebral artery occlusion (MCAO) in rats at 3T MRI, and to validate NODDI metrics with histology. A multi-shell diffusion MRI protocol was performed on 11 MCAO rats and 10 control rats at different post-operation time points of 0.5, 2, 6, 12, 24 and 72 h. NODDI orientation dispersion index (ODI) and intracellular volume fraction (Vic) metrics were compared between MCAO group and control group. The evolution of NODDI metrics was characterized and validated by histology. Infarction was consistent with significantly increased ODI and Vic in comparison to control tissues at all time points (P<0.001). Lesion ODI increased gradually from 0.5 to 72 h, while its Vic showed a more complicated and fluctuated evolution. ODI and Vic were significantly different between hyperacute and acute stroke periods (P<0.001). The NODDI metrics were found to be consistent with the histological findings. In conclusion, NODDI can reflect microstructural changes of brain tissues in MCAO rats at 3T MRI and the metrics are consistent with histology. This study helps to prepare NODDI for the diagnosis and management of ischemic stroke in translational research and clinical practice.

Multi-Block Color-Binarized Statistical Images for Single-Sample Face Recognition.

Single-Sample Face Recognition (SSFR) is a computer vision challenge. In this scenario, there is only one example from each individual on which to train the system, making it difficult to identify persons in unconstrained environments, mainly when dealing with changes in facial expression, posture, lighting, and occlusion. This paper discusses the relevance of an original method for SSFR, called Multi-Block Color-Binarized Statistical Image Features (MB-C-BSIF), which exploits several kinds of features, namely, local, regional, global, and textured-color characteristics. First, the MB-C-BSIF method decomposes a facial image into three channels (e.g., red, green, and blue), then it divides each channel into equal non-overlapping blocks to select the local facial characteristics that are consequently employed in the classification phase. Finally, the identity is determined by calculating the similarities among the characteristic vectors adopting a distance measurement of the K-nearest neighbors (K-NN) classifier. Extensive experiments on several subsets of the unconstrained Alex and Robert (AR) and Labeled Faces in the Wild (LFW) databases show that the MB-C-BSIF achieves superior and competitive results in unconstrained situations when compared to current state-of-the-art methods, especially when dealing with changes in facial expression, lighting, and occlusion. The average classification accuracies are 96.17% and 99% for the AR database with two specific protocols (i.e., Protocols I and II, respectively), and 38.01% for the challenging LFW database. These performances are clearly superior to those obtained by state-of-the-art methods. Furthermore, the proposed method uses algorithms based only on simple and elementary image processing operations that do not imply higher computational costs as in holistic, sparse or deep learning methods, making it ideal for real-time identification.

Protocols for orthodontic treatment of patients with temporomandibular joint disorders

Orthodontists often have trouble treating patients who have temporomandibular joint disorders because occlusion changes depend on the position of unstable condyles. This characteristic means the patients do not have definite criteria with which to make an accurate orthodontic diagnosis, so clinicians are unable to establish a reliable treatment plan. This article reports on the treatment of a patient with skeletal Class II relationship and condylar resorption. A stabilization splint was used before any active orthodontic tooth movement to stabilize her condylar position. Although the patient exhibited dramatically increased open bite and a retruded mandibular position after splint therapy, her occlusion and facial esthetics were resolved by orthodontic camouflage treatment withappropriate orthodontic mechanics after extraction of 4 premolars.

Learning adaptive spatial regularization and aberrance repression correlation filters for visual tracking

This paper proposes a correlation filter tracking algorithm based on adaptive spatial regularization and aberrance repression aiming at the problem that the spatial regularization weight of the background-aware correlation filter is fixed and does not adapt to the change of the target, and the problem that enlarging search area may introduce background noise, decreasing the discrimination ability of filters. First, FHOG features, CN features, and gray features are extracted to enhance the algorithm's ability to express the target. Second, aberrance repression terms are added to the target function to constrain the response map of the current frame, and to enhance the filter's discrimination ability to alleviate the filter model degradation. Finally, adaptive spatial regularization terms are added to the objective function to make the spatial regularization weights being updated as the objective changes, so that the filter can make full use of the target's diversity information. This paper involves experiments on the public data sets OTB-2013, OTB-2015 and VOT2016 to evaluate the proposed algorithm. The experimental results show that the speed of the algorithm used in this paper is 20 frames/s, evaluation indicators such as distance accuracy and success rate are superior to comparison algorithms, and it has good robustness in a variety of complex scenarios such as occlusion, background interference, and rotation changes.

A comparative study of 14 state of art descriptors for face recognition

This research paper presents a comparative study between 14 state of art descriptors which includes Local Binary Pattern (LBP), Median Binary Pattern (MBP), 6 × 6 Multiscale Block LBP (6 × 6 MB-LBP), Local Neighborhood Difference Pattern (LNDP), Logically Connected-LBP (LC-LBP), Local Phase Quantization (LPQ), Compound LBP (CLBP), Horizontal Elliptical LBP (HELBP), Vertical Elliptical LBP (VELBP), ELBP, Neighborhood Intensity Based LBP (NI-LBP), Median Robust Extended LBP Based on NI (MRELBP-NI), Radial Difference-LBP (RD-LBP) and Transition LBP (tLBP). For all the descriptors the features are extracted globally and the dimensionality of the feature size is reduced by employing Principal Component Analysis (PCA) and Fishers Linear Discriminant Analysis (FLDA). Finally classification is performed by Support Vector Machines (SVMs) and Nearest Neighbor (NN). Experiments are performed on 8 challenging databases which covers all the major challenges such as pose variations, illumination variations, expression variations and occlusion changes. The 8 challenging databases includes ORL, GT, Faces94, MIT-CBCL, Yale, YB, EYB and SOF. Out of all the descriptors it is the performance of the CLBP descriptor which is most encouraging. On some occasions the MRELBP-NI descriptor also achieves good results. But all in all the CLBP descriptor achieves the best results. In addition to this Deep learning based descriptors are also discussed in the paper.

Management of Class II Hyperdivergent Mandible by Surgically Altering Occlusal Plane Pattern through Counterclockwise Rotation of Mandible

To evaluate the facial esthetic of class II hyperdivergent mandible by altering the high mandibular plane angle into an orthognathic mandibular plane angle by counterclockwise (CCW) rotation of the mandible. Five patients with class II hyperdivergent mandible were selected for this study. Initially, preorthodontics was done by aligning the teeth. Then, surgically, bilateral sagittal split osteotomy (BSSO) advancement with CCW rotation of mandible with a posterior open bite of 4 mm was done. Eleven linear and 11 angular measurements were taken. Pre- and postsurgical values were evaluated by composite cephalometric analysis, and the changes in the occlusal plane and facial height were statistically analyzed by using paired t-test. Jarabak ratio was calculated for facial height measurements. Further finishing will be done by postsurgical orthodontic procedures to get functional occlusion. Change in occlusion to class I is seen in values of Jarabak ratio and Go-Gn. Jarabak ratio shows an increase in posterior and decreases in anterior facial height. Go-Gn, which implies the CCW movement of the mandible, has reduced the anterior open bite and created a posterior open bite of 4 mm for the supraeruption of teeth. BSSO with CCW rotation of mandible with a posterior open bite has conservatively involved in single-jaw surgery, thereby improving the facial esthetics of all the patients taken this study. This innovative method of CCW rotation of mandible with open bite mainly prevents the bi-jaw surgery, improves the stability, and gives an esthetically good appearance.