Evaluation of the neuromotor ability of the tongue in pediatric patients using a stereognostic examination.

BACKGROUND: The term "stereognosis" comes from neurology and describes the capacity to distinguish objects solely by touch. AIM: The aim of this research study was to compare the neuromotor ability of the tongue in patients with malocclusion and tongue dysfunction with and without superficial anesthesia on the tip of the tongue and hard palate. MATERIALS AND METHODS: The study included 132 patients aged 6-13 years. Using a spatula for speech therapy and a visual evaluation while swallowing saliva, all individuals were identified as having swallowing dysfunctions and divided into three groups: study group (children with malocclusions and tongue dysfunctions) - 44 patients, comparator group (children with malocclusions and without tongue dysfunctions) - 44 patients, and control group (children without malocclusions or tongue dysfunctions) - 44 patients. The Koczorowski methods were used for the stereognostic tests. RESULTS: Age, sex, and malocclusion were taken into account during the differential analysis. The study and comparison groups, study and control groups, and the comparator and control groups all showed statistically significant differences from one another. According to the results, tongue dysfunction affects patients' ability to coordinate their movements with their senses at a developing stage. CONCLUSION: Patients with malocclusions that are made worse by tongue dysfunctions have poorer oral stereognostic sensibility. Speech therapy and interdisciplinary specialist orthodontic treatment are required for individuals with impaired oral perception who are still in the developmental stage and have abnormal tongue position and function.

Infraocclusion in the Primary and Permanent Dentition-A Narrative Review.

The gradual movement of a tooth away from the occlusal plane is called infraocclusion or reinclusion. Reincluded teeth are most often deciduous molars, and permanent teeth are less frequently affected. Depending on the level of the infraocclusion, the severity of the disorder is classified as mild, moderate, or severe. The etiology of the phenomenon is not fully known. Tooth submerging can lead to serious complications, such as abnormal position of adjacent teeth, displacement of the bud of the permanent successor, shortening of the dental arch, or developmental disturbances of alveolar process. Early diagnosis of the tooth infraocclusion and regular monitoring of its progression help to avoid serious permanent sequelae. The treatment of reinclusion often involves only observation. However, in some cases, the therapeutic procedure requires interdisciplinary treatment by specialists from various fields of dentistry. This study presents current methods of diagnosis and treatment of patients with submerged teeth.

Malocclusions, Sleep Bruxism, and Obstructive Sleep Apnea Risk in Pediatric ADHD Patients: A Prospective Study.

OBJECTIVES: Literature presents conflicting results regarding malocclusions, Obstructive Sleep Apnea (OSA) and sleep bruxism in children with ADHD. Aim of this study was to evaluate the prevalence of these parameters. METHODS: A prospective study was conducted on 40 consecutive ADHD children referred to the Paediatric Dentistry Unit of Fondazione Policlinico Universitario "A. Gemelli" IRCCS, Rome. All subjects underwent an orthodontic examination and were screened for OSA and sleep bruxism. Data were compared to a sex- and aged-matched control group. RESULTS: Prevalence of high risk of OSA in children with ADHD was 62.5% compared to 10% in the control group (p < .00001). No differences were found in any of the occlusal variables examined between children with ADHD and controls (p > .05). An increased prevalence of sleep bruxism was observed in ADHD children (40%) compared to controls (7.5%) (p < .001). CONCLUSIONS: A higher prevalence of OSA risk and probable sleep bruxism were observed in ADHD patients compared with controls. No significant differences were observed in malocclusions d.

Development of occlusal canting identifying tool: verification, reliability and validation assessment.

INTRODUCTION: Occlusal cant (OC) is a malocclusion trait that lacks accurate clinical assessment methods. The occlusal canting identifying tool (OCIT) was invented and patented as a clinical tool to accurately identify and quantify the degree of maxillary OC. This study aimed to 1) develop a prototype of the OCIT, 2) verify the functionality of the OCIT and 3) assess the validity and reliability of the OCIT. MATERIALS AND METHODS: A patented OCIT design was revised, and the dimensions were finalized, followed by a three-dimensional conceptual prototype design that was reviewed and approved by the inventors. Verification was performed using a digital angle gauge to determine the accuracy of the bubble level as well as the angle between the bite plate and the protractor. For laboratory validation, 40 orthodontists measured the simulated OC at (0°, 2°, 4°, 6° and 8°) on five phantom heads using the OCIT. A reliability assessment of the tool was performed in three occasions by one orthodontist using the same laboratory settings. RESULTS: The OCIT was prototyped from a medical-grade stainless steel alloy (316 L). Verification assessment revealed that the accuracy error of the bubble level (0.316° ± 0.028°) was statistically significant but clinically insignificant, while that of the angle between the bite plate and protractor (0.100° ± 0.050°) was statistically insignificant. Validation assessment showed high validity of the OCIT with no statistically significant difference between the OCIT and the reference values, having more errors in identifying smaller OC degrees compared to larger OC degrees. The intraclass correlation coefficient indicated the high reliability of the OCIT. CONCLUSION: The OCIT was verified and proven to be a valid and reliable clinical tool that accurately evaluates the degree of OC.

Cross-cultural adaptation and validation of the Chinese version of the Malocclusion Impact Scale for Early Childhood (MIS-EC/C).

BACKGROUND: The Malocclusion Impact Scale for Early Childhood (MIS-EC) is a newly developed questionnaire used to measure the parental perceptions of the impact of malocclusion on oral health-related quality of life (OHRQoL) of preschool children aged 3-5 years. This study describes the cross-cultural adaptation and validation of the MIS-EC questionnaire into Chinese version (MIS-EC/C). METHODS: The MIS-EC/C was developed in accordance with international standards. The scale was then evaluated in a cross-sectional study comprising 210 preschool children aged 3-5 years. The reliability of the MIS-EC/C was tested using internal consistency and test-retest reliability analyses. Cross-cultural validity, discriminant validity and convergent validity were tested. RESULTS: The Cronbach's α value and intraclass correlation coefficient (ICC) value for the MIS-EC/C were 0.943 and 0.873, respectively. Confirmatory factor analysis indicated that the fitting indicators of the two-factor model all reached the standard. The MIS-EC/C can differentiate preschool children with malocclusion from those without malocclusion. In addition, there is a good relationship between the MIS-EC/C and the general oral health question. CONCLUSION: The MIS-EC/C is a reliable and effective assessment tool for assessing the effect of malocclusion on the OHRQoL of preschool children in China.

Orthodontic Implementation of Machine Learning Algorithms for Predicting Some Linear Dental Arch Measurements and Preventing Anterior Segment Malocclusion: A Prospective Study.

Background and Objectives: Orthodontics is a field that has seen significant advancements in recent years, with technology playing a crucial role in improving diagnosis and treatment planning. The study aimed to implement artificial intelligence to predict the arch width as a preventive measure to avoid future crowding in growing patients or even in adult patients seeking orthodontic treatment as a tool for orthodontic diagnosis. Materials and Methods: Four hundred and fifty intraoral scan (IOS) images were selected from orthodontic patients seeking treatment in private orthodontic centers. Real inter-canine, inter-premolar, and inter-molar widths were measured digitally. Two of the main machine learning models were used: the Python programming language and machine learning algorithms, implementing the data on k-nearest neighbor and linear regression. Results: After the dataset had been implemented on the two ML algorithms, linear regression and k-nearest neighbor, the evaluation metric shows that KNN gives better prediction accuracy than LR does. The resulting accuracy was around 99%. Conclusions: it is possible to leverage machine learning to enhance orthodontic diagnosis and treatment planning by predicting linear dental arch measurements and preventing anterior segment malocclusion.

Evaluation of occlusal bite force distribution by T-Scan in orthodontic patients with different occlusal characteristics: a cross sectional-observational study.

BACKGROUND: The aim of orthodontic treatment, apart from esthetic and functional corrections, is uniform force distribution. Hence Occlusal analysis using a T scan gives scope for a precisely targeted treatment plan. The T-scan evaluation of occlusal force, time, and location of contacts from initial occlusal contact to maximum intercuspation enables the orthodontist to sequentially balance the occlusal forces on the right and left sides through specific treatment plan options. OBJECTIVE: The current study aimed to determine the force distribution in the different individuals by using a T-Scan as well as the net discrepancies of forces generated at a maximum intercuspation position in the first molar region between the left and right sides of the mouth. METHODS: This is a descriptive-correlational study that was carried out in Ras Al Khaimah College of Dental Sciences clinics and Ajman University clinics from January 2020 to September 2022 by using the convenience sampling technique. The T-scan III Novus was employed in this investigation to record multi-bite scans for several patients. T-scan was utilised to examine various malocclusions. RESULTS: The present study consisted of 158 participants. Analysis of Variance (ANOVA) showed that there is a statistically significant difference in the percentage of force between the three types of malocclusions (I, II, and III) on the right molar side (B-16 and B-46) (p < 0.05). Moreover, the overall discrepancy showed a statistically significant difference in the three types of malocclusion classifications (p < 0.05). On the other hand, there was no statistically significant difference in the percentage of force between B-26 and B-36 (p > 0.05). Post hoc analysis showed a statistically significant difference in the percentage of force between malocclusion classes I and III on the right molar, with a mean difference of 4.11190 (p < 0.05). Similarly, there was a statistically significant difference in B-46 between Malocclusion Classes I and II, 4.01806 (p < 0.05). Additionally, post hoc analysis showed a statistically significant difference between malocclusion classes I and III, with a mean difference of -4.79841 (p < 0.05) on the right molar. CONCLUSION: The T-Scan is a useful tool for assessing occlusal discrepancies and can be helpful during treatment planning and follow-up, especially for orthognathic surgery patients. A T-scan could be used in orthodontic therapy in a simple and efficient way. Also, it turned out to be a useful tool for diagnosing problems and gave us new information about how therapies work. In this study, T-Scan showed that it can measure occlusal forces in timing in an objective, accurate, and repeated manner. The current study found that T-Scan was better able to report the difference in the percentage of force on the right molar side than on the left side.

Implications of occlusal plane in diagnosis and treatment of malocclusion. / 平面对错 畸形诊断和治疗的意义.

Occlusal plane (OP) is one of the essential factors affecting craniofacial morphology and function. The OP not only assists in diagnosing malocclusion but also serves as an important reference for making treatment plans. Patients with different types of malocclusions have different forms of OP. Compared with patients with standard skeletal facial type, the occlusal plane of patients with skeletal class Ⅱ and high angle is steeper, while that of patients with skeletal class Ⅲ and low angle is more even. In orthodontic treatment, adjusting and controlling the OP can promote the normal growth and development of the mandible in most patients with malocclusion during the early stage of growth, while causing favorable rotation of the mandible in some adults with mild-to-moderate malocclusion. For moderate-to-severe malocclusion, the OP rotation by orthodontic-orthognathic treatment can achieve better long-term stability. This article reviews the evolution of the definition of OP and its implications for diagnosing and the guiding treatment of malocclusion.

[A reflectional insight into orthodontic theoretical renovation and technological innovation].

Orthodontics, among other specialties in dentistry, remains most dynamic and vigorous in upgrading and reforming its fundamental doctrines and clinical technologies. Orthodontic specialty in China has played a leading role in recent years in reshaping fundamental theories and in creating cutting-edge therapeutic modalities. The newly developed diagnostic classification system, a complementary addition to that of Angle's, not only defines the natures, but also identifies the developmental mechanisms of malocclusions. Orthopedic therapy aiming to relocate the mandible before correcting the dentition is emerging as an indispensable treatment mode to malocclusions concurring with mandibular deviation. Whilst correlations exist between malocclusion and TMD susceptibility and incidence, the specifically designed orthopedic and orthodontic approaches have proven effective in managing cases inflicted by TMD conditions. Innovative efforts that create the GS products, have redefined the clear appliances much more beyond merely clear aligners, thus further pushing the boundaries of both the indications and clinical use for clear appliances.

Clinical research on the relationship between the curve of Wilson and temporomandibular joint disorders.

OBJECTIVE: The aim of this study was to examine the relationship between the curve of Wilson (COW) and temporomandibular joint disorder (TMD). METHODS: The study cohort comprised patients aged 19-55 with malocclusion treated at our institution from January to July 2021. They were divided into a malocclusion with TMD group (TMD group) and a malocclusion without TMD group (non-TMB group) based on the diagnostic criteria of TMD. The study outcome was the differences in COW, measured via cone beam computed tomography (CBCT), and statistical analysis was performed using one-way analysis of variance and t-test. RESULTS: A total of 250 adult individuals were enrolled, including 162 females (age: 36.43 ± 11.00 years) and 88 males (age: 36.33 ± 9.88 years). Compared with the non-TMB group (n = 125), the TMD group (n = 125) had a significantly greater angle of COW (first molars: P = 0.002; second molars: P < 0.001), higher buccal inclination angle of molars in those with same side temporomandibular joint (TMJ) sounds than those with TMJ sounds (first molar: P = 0.000; second molar: P = 0.006) and greater the side with TMJ sounds (first molar: P < 0.001; second molar: P = 0.016). However, no difference was observed in the buccolingual axial inclination angle of molars between patients with and without TMJ sounds. CONCLUSION: The study reported the differences in malocclusion patients with and without TMB, which could be used as a reference by dentists to improve the treatment outcomes of these patients.

THE DETERMINATION OF THE NEED TO PROVIDE ORTHODONTIC ASSISTANCE TO TEENAGERS IN CONDITIONS OF LIMITED RESOURCES.

OBJECTIVE: The aim: To substantiate the need for a combination of interdisciplinary approaches to diagnosis, treatment and correction of dento-maxillofacial anomalies of teenagers based on the analysis of the need for orthodontic treatment using the DAI, IOTN, ICON aesthetic indices. PATIENTS AND METHODS: Materials and methods: Empirical, epidemiological, clinical, analytical-synthetic, sociological, psychological research methods, questionnaires, dental indexeshave been used in various combinations. RESULTS: Results: As a result of a clinical examination of 2,260 teenagers (1,096 boys and 1,124 girls), 1,474 individuals have been bselected for orthodontic treatment with the following degree of complexity: mild - in 25 examined (35.71±4.95%), moderate - in 31 individuals (44.28± 5.48%), heavy - 14 (20.00±3.11%). After an in-depth dental examination and determination of the psychological profile, 70 teenagers have been selected for treatment. CONCLUSION: Conclusions: The effectiveness of the use of dental indices as a screening tool to eliminate the discrepancy between objective medical indicators of the level of need for correction of dento-maxillofacial anomalies and the level of expected results in adolescents has been proven.

Prevalence of tooth loss, bleeding on probing and malocclusion as oral disease indicators in Costa Rican male adolescents: a cross sectional study / Prevalencia de la pérdida de piezas dentales, del sangrado al sondeo y la maloclusión como indicadores de enfermedades orales en adolescentes varones costarricenses: un estudio transversal

The evidence to characterize oral health during adolescence in Costa Rica is limited. This lack of adequate research makes it difficult to develop appropriate health policies for this subgroup of the population. This is particularly important because adolescence is the period during which good health habits must take root in order to foster good physical and cognitive development. This study aims to determine the prevalence of tooth loss, bleeding on probing and malocclusion in Costa Rican male adolescents at the ''Colegio Técnico Profesional San Agustín'' (St. Augustine's Technical High School) located in the province of Cartago. Data was collected from 428 male adolescents aged 12-22 years in a cross-sectional study during 2019. Prevalence of tooth loss was calculated as the number of individuals having lost at least one tooth. The average number of teeth lost by individuals was also recorded. The bleeding on probing was an indicator used as a proxy parameter for monitoring periodontal health where the presence of bleeding on probing and calculus was also recorded. Malocclusion was measured using the Dental Aesthetic Index (DAI). The results showed that the prevalence of tooth loss, bleeding on probing and malocclusion was of 19%, 70.0% and 98%, respectively. It was also found that 81% of the participants had all their teeth, 11% had lost 1 tooth, 8% had lost more than one tooth of which 0.5% had lost more than 5 teeth. Considering a general classification of periodontal problems based on bleeding on probing and presence of calculus, the prevalence of periodontal problems increases to 92%. Regarding the DAI, the category identifying a very severe malocclusion was the most prevalent in the sample (88%). It is alarming the high prevalence of tooth loss, bleeding on probing, and malocclusions in a sample of Costa Rican male adolescents, compared to similar studies in other countries. The overarching conclusion of this study is that oral diseases represent an important health problem that urgently need proper public health action.

La evidencia para caracterizar la salud bucal durante la adolescencia en Costa Rica es limitada. Esta falta de investigación adecuada dificulta el desarrollo de políticas de salud convenientes para este subgrupo de la población. Esto es particularmente importante porque la adolescencia es el período durante el cual se deben arraigar buenos hábitos de salud para fomentar un buen desarrollo físico y cognitivo. Este estudio tiene como objetivo determinar la prevalencia de pérdida de piezas dentales, sangrado al sondeo y maloclusión en adolescentes varones costarricenses del Colegio Técnico Profesional San Agustín ubicado en la provincia de Cartago. Se recopilaron datos de 428 adolescentes varones de 12 a 22 años en un estudio transversal durante 2019. La prevalencia de pérdida de piezas dentales se calculó como el número de individuos que habían perdido al menos una pieza dental. También se registró el número promedio de dientes perdidos por individuos. El sangrado al sondeo fue un indicador utilizado como parámetro para el seguimiento de la salud periodontal donde también se registró la presencia de sangrado al sondeo y cálculo dental. La maloclusión se midió utilizando el Índice Estético Dental (DAI, por sus siglas en inglés). Los resultados mostraron que la prevalencia de pérdida de piezas dentales, sangrado al sondeo y maloclusión fue del 19%, 70,0% y 98%, respectivamente. También se encontró que el 81% de los participantes tenían todos sus dientes, el 11% había perdido 1 pieza dental, el 8% había perdido más de una pieza dental, de los cuales el 0,5% había perdido más de 5 piezas dentales. Considerando una clasificación general de problemas periodontales basada en sangrado al sondeo y presencia de cálculo, la prevalencia de problemas periodontales aumenta al 92%. En cuanto al DAI, la categoría que identifica una maloclusión muy severa fue la más prevalente en la muestra (88%). Es alarmante la alta prevalencia de pérdida de piezas dentales, sangrado al sondeo y maloclusiones en una muestra de adolescentes varones costarricenses, en comparación con estudios similares en otros países. La conclusión general de este estudio es que las enfermedades bucodentales representan un importante problema de salud que necesita urgentemente una acción adecuada de salud pública.

An adult case of unilateral posterior crossbite caused by maxillary transverse deficiency treated with miniscrew-assisted rapid palatal expansion.

This report describes the successful treatment of an adult case of unilateral posterior crossbite caused by maxillary transverse deficiency with miniscrew-assisted rapid palatal expansion (MARPE). A female patient aged 35.5 years presented with masticatory disturbance, facial asymmetry, and unilateral posterior crossbite. She was diagnosed with unilateral posterior crossbite with a skeletal Class III jaw-base relationship and high mandibular plane angle. Her maxillary right and mandibular bilateral second premolars were congenitally absent, and the maxillary left second premolar was impacted. After the improvement of the posterior crossbite with MARPE, 0.018″ slot lingual brackets were placed on the maxillary and mandibular dentition. The total active treatment period was 22 months, and acceptable occlusion with a functional Class I relationship was achieved. Pretreatment and posttreatment cone-beam computed tomography images showed the disarticulation of the midpalatal suture after MARPE, and changes in the dental and nasomaxillary structures, nasal cavity, and pharyngeal airway. The case results demonstrate that MARPE produces greater skeletal expansion with minimal buccal tipping of the molars. MARPE may be effective for the treatment of maxillary transverse deficiency in adult patients.

Evaluation of artificial intelligence model for crowding categorization and extraction diagnosis using intraoral photographs.

Determining the severity of dental crowding and the necessity of tooth extraction for orthodontic treatment planning are time-consuming processes and there are no firm criteria. Thus, automated assistance would be useful to clinicians. This study aimed to construct and evaluate artificial intelligence (AI) systems to assist with such treatment planning. A total of 3,136 orthodontic occlusal photographs with annotations by two orthodontists were obtained. Four convolutional neural network (CNN) models, namely ResNet50, ResNet101, VGG16, and VGG19, were adopted for the AI process. Using the intraoral photographs as input, the crowding group and the necessity of tooth extraction were obtained. Arch length discrepancy analysis with AI-detected landmarks was used for crowding categorization. Various statistical and visual analyses were conducted to evaluate the performance. The maxillary and mandibular VGG19 models showed minimum mean errors of 0.84 mm and 1.06 mm for teeth landmark detection, respectively. Analysis of Cohen's weighted kappa coefficient indicated that crowding categorization performance was best in VGG19 (0.73), decreasing in the order of VGG16, ResNet101, and ResNet50. For tooth extraction, the maxillary VGG19 model showed the highest accuracy (0.922) and AUC (0.961). By utilizing deep learning with orthodontic photographs, dental crowding categorization and diagnosis of orthodontic extraction were successfully determined. This suggests that AI can assist clinicians in the diagnosis and decision making of treatment plans.

Prevalence of malocclusions in 8- and 9-year-old children in Germany-Results of the Sixth German Oral Health Study (DMS 6).

PURPOSE: Current population-wide data on the prevalence of malocclusions in 8­ and 9­year-old children in Germany are not available. Therefore, the primary objective of this study was to collect data on the prevalence of malocclusions in 8­ and 9­year-old children in Germany. The secondary objective of this study was to use this information to derive the need for orthodontic care provision. METHODS: This is an oral-epidemiological investigation and social science survey at the national level with a focus on tooth and jaw misalignment. The investigation took place between January and March 2021 at 16 study centers across Germany. All relevant data were available for the 705 study participants and were included in the statistical analysis. RESULTS: Overbite was the most common finding with 88.9%. Also widespread were crowding, with at least 60.9%, and lack of space, with a share of 30.9%. All other indication groups had a share below 10%. Rare (< 1%) were buccal and lingual occlusions and craniofacial abnormalities. The most severe forms of disease (Orthodontic Indication Group [Kieferorthopädische Indikationsgruppen, KIG] grade 5) were overbite (3.2%), open bite malocclusion (1.0%), undershot (0.6%), and craniofacial abnormalities (0.4%). The proportion of study participants who required orthodontic treatment, in accordance with statutory health insurance provider guidelines, was 40.4%. The proportion of study participants in principle requiring orthodontic treatment for medical reasons was 97.5%. Systemic differences in the need for orthodontic care provision relating to gender, region, or social status were not identified. CONCLUSION: In general, the need for care provision identified in the orthodontic indication groups corresponds to that shown in previous studies. This suggests that the need for orthodontic treatment in Germany has remained stable over the years.

Does orthodontic treatment need have an impact on oral health-related quality of life?

OBJECTIVES: The aims of this study were to determine the frequency of oral health-related quality of life (OHRQoL) impairment in a national representative sample of 8 to 9 year olds in Germany and to evaluate the impact of orthodontic treatment need. METHODS: Data were collected in the Sixth German Oral Health Study (Sechste Deutsche Mundgesundheitsstudie, DMS 6) and subjects were sampled using a multistage sampling technique. OHRQoL was measured with a modified version of the 5­item Oral Health Impact Profile (OHIP-5) which was administered in a computer-assisted personal interview. Children were also examined for malocclusion and orthodontic treatment need. RESULTS: In all, 1892 children aged 8-9 years were invited to take part. Finally, data of 705 children (48.6% female) could be included in the analysis. The OHIP­5 mean was 1.3 (±2.0). There was no relevant influence from age and gender on the OHIP­5 summary scores (r < 0.10), but the summary scores differed when analyzed separately regarding orthodontic treatment need or no orthodontic treatment need (1.5 ± 2.0 vs. 1.2 ± 1.9, p = 0.020). Nevertheless, the level appears to be low. CONCLUSIONS: Malocclusions with orthodontic treatment need have an influence on OHRQoL.

Comparison of orthodontic treatment need and malocclusion prevalence according to KIG, ICON, and mIOTN in German 8- to 9-year-old children of the Sixth German Oral Health Study (DMS 6).

PURPOSE: The aim of the present study was to compare the malocclusion indices KIG (Kieferorthopädische Indikationsgruppen, Orthodontic Indication Groups), ICON (Index of Complexity, Outcome and Need), and mIOTN (modified Index of Orthodontic Treatment Need) regarding differences in malocclusion prevalence and their assessment of orthodontic treatment need in German 8­ to 9­year-old children of the Sixth German Oral Health Study (Deutsche Mundgesundheitsstudie, DMS 6). METHODS: The necessary data for the calculation of the KIG, mIOTN, and ICON were collected by a dentist as part of a clinical orthodontic examination during the field phase of the DMS 6 and by a subsequent digital orthodontic model-analytical evaluation of intraoral scans of the dental arches and the occlusal situation in habitual occlusion. RESULTS: Prevalence, severity, and treatment need of tooth and jaw misalignments differed in part considerably depending on the index used for assessment. On the other hand, there were several outcomes which yielded quite similar results for the different indices used, such as orthodontic treatment need, which ranged from 40.4% (KIG) over 41.6% (ICON) to 44.2% (mIOTN). Interestingly, orthodontic treatment need for the individual subject could differ considerably, when assessed using different indices. CONCLUSIONS: In general, the results show that the mIOTN is much more conservative in assessing malocclusion prevalences often being smaller than those derived by KIG or ICON. In contrast, KIG and ICON often yield similar prevalences with certain distinct differences due to discrepancies in the respective definitions and also clearly differentiate between treatment possibility and arbitrarily determined treatment need.

Upper arch dimensional changes with clear aligners in the early mixed dentition : A prospective study.

BACKGROUND: One goal of orthodontic treatment in mixed dentition is to expand the maxillary arch to allow proper tooth alignment and a correction of sagittal and vertical malocclusions. However, for most treatment protocols, expected outcome is not really clear to allow for a standardization of phase I orthodontic treatments. This lack of information makes it difficult for clinicians to predict tooth movements, including transverse expansion efficacy with Invisalign® (Align Technology, Santa Clara, CA, USA) in children. Therefore, the aim of the present study was to evaluate the transverse maxillary arch development with the Invisalign First System® in growing subjects. METHODS: The study group included 23 subjects (9 females, 14 males, mean age 9.4 ± 1.2 years). Patients were treated nonextraction with Invisalign First System® clear aligners with no auxiliaries other than Invisalign® attachments. Transverse interdental widths were measured only in the upper arch on each model at the start (T1) and at the end (T2) of treatment. A paired t­test was chosen to compare T2-T1 changes. The level of significance was set at 5%. RESULTS: The greatest increase of maxillary width was detected at the level of the upper first deciduous molars (+3.7 ± 1.4 mm; P < 0.001), followed by the level of the second deciduous molars (+3.4 ± 1.6 mm; P < 0.001) and by the deciduous canine (+2.6 ± 2.0 mm; P < 0.001). Upper first molars showed a greater expansion in the intermolar mesial width (+3.2 ± 1.2 mm; P < 0.001) than in the intermolar distal (+1.7 ± 1.2 mm; P < 0.001) and transpalatal width (+1.2 ± 1.2 mm; P < 0.01). CONCLUSIONS: The Invisalign First System® can be considered effective in growing patients who require maxillary arch development. The greatest net increase was detected at the level of upper first deciduous molars, whereas the upper first molars showed a greater expansion in the intermolar mesial width due to a rotation that occurs around its palatal root.

Evaluation of occlusal function during orthognathic therapy : A prospective clinical trial using a digital registration method.

OBJECTIVES: Reduced occlusal function is a main characteristic of orthognathic patients. The present study aimed to investigate the extent of therapy-induced functional improvements in occlusal function using a digital diagnostic method. METHODS: This prospective clinical study included 41 orthognathic patients (24 women and 17 men, median age 27.26 ± 8.2 years) and 10 control patients (5 women and 5 men, median age 29.8 ± 13.5 years) with neutral skeletal and dental configurations. The patients were divided into classes I, II and III based on their cephalometry. Digital occlusal registrations in habitual occlusion in an upright sitting position were taken before (T1) and after (T2) therapy using the T­Scan Novus (Tekscan, South Boston, MA, USA) application. RESULTS: Class II and III patients showed a significantly less efficient occlusal pattern than the untreated controls regarding total antagonism (p < 0.001), time of occlusion (p = 0.004), occlusal asymmetry (p = 0.001), anterior antagonism (p < 0.001) and posterior antagonism (p < 0.001). After therapy, the occlusal pattern increased in both therapy groups, where class III patients became indistinguishable from the controls, and class II patients differed only in posterior antagonism (p = 0.035). CONCLUSIONS: The digital occlusal registration method proved to be a useful diagnostic tool and provided new insights into therapeutic effects in orthognathic patients. By precisely adjusting the occlusal function, masticatory performance improved significantly. CLINICAL RELEVANCE: Severe malocclusion leads to a significantly lower masticatory performance for patients, which can be improved by orthognathic therapy and captured by digital occlusal registration.