Evaluation of the perception of smile esthetics, in frontal view, with mandibular laterognatism, through the eye-tracking technique.

OBJECTIVES: To evaluate the perception of esthetics and the attractiveness of the smile, in frontal view, with mandibular asymmetry, through the eye-tracking. MATERIALS AND METHODS: OGAMA software and The Eye Tribe Tracker hardware were used to obtain eye tracking in certain areas of interest on the face. To simulate asymmetry, Photoshop® image editing software was used to create a vertical reference line to the midline of the face and make it symmetrical with control of the angulation relative to another horizontal reference line passing through the vertices. Then, the lower third of the face added asymmetries or deviations, starting from zero, with increments of 2 by 2 degrees up to 6 degrees. The study included 60 laypeople, 30 males and 30 females, without any knowledge about the study, showing good vision, and not having used drugs with the possibility of influencing cognitive or motor skills. RESULTS: From the heat map in cases of mandibular asymmetry, it is possible to visualize that for both sexes the evaluators evaluated with a certain degree of similarity mainly when the deviations presented with 6 degrees. The trajectory of the male and female gaze in cases with asymmetry shows that in cases with a magnitude of 6 degrees, the raters traced mainly in the region of the mouth with little transition in the eye region and mainly in the areas of interest considered as "other." In the images presented with a magnitude of up to 4 degrees, they were traced in the general image. CONCLUSIONS: The perception of laypeople from mandibular asymmetry to the right in females presented a higher perception when compared to males with mandible asymmetry to the left.

Effectiveness of casein phosphopeptide-amorphous calcium phosphate-containing products in the prevention and treatment of white spot lesions in orthodontic patients: A systematic review.

The purpose of the present systematic review was to evaluate the effectiveness of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP)-containing products in the prevention and treatment of active white spot lesions (WSL) in orthodontic patients. Searched the Scopus, PubMed, Web of Science, Cochrane, Virtual Health Language, ClinicalTrials, and Open Gray databases without limitations on the year or language of publication. We included controlled clinical trials with patients with fixed orthodontic appliances under the use of CPP-ACP-containing products compared to control, placebo, or other interventions in the prevention and treatment of WSL around orthodontic braces. Case reports, editorials, in vitro studies, annals of congress, and reviews were excluded. To assess the risk of bias, the revised version of the Cochrane tool for randomized trials (RoB 2.0) and Risk Of Bias In Non-randomized Studies for non-randomized trials were used. The biases were graded low, moderate, and high according to the tools used. Of the 599 articles found, 11 met the inclusion criteria. Of these, nine were randomized, controlled clinical trials and two were non-randomized. Two studies were considered to have moderate bias risk, and the most-used CPP-ACP presented form was a cream for topical applications. Although CPP-ACP-containing products did not differ from other fluoride products, they were able to reduce WSL and neutralize the pH around the orthodontic braces. Products containing CPP-ACP are effective in preventing and treating WSL around the braces. However, further studies with the same measurement method and periods of use, and other forms of presentation of CPP-ACP are needed.

Miniscrew Composition, Transmucosal Profile, and Cortical Bone Thickness: A Three-dimensional Finite-element Analysis of Stress Fields.

AIM: The aim of this study was to use the finite-element method (FEM) to analyze the stress fields generated in miniscrews (MSs) and surrounding bone on applying a force perpendicular to the MS according to variations in the cortical bone thickness and changes in the transmucosal profile length and MS composition. MATERIALS AND METHODS: Miniscrews with stainless steel (SS) and titanium alloy mechanical properties with a 1 to 2 mm transmucosal profile inserted in bone blocks with cortical bone of varying thickness (1 and 2 mm) were three-dimensionally modeled using computer-aided design (CAD) and examined using FEM. A 3.5 N force perpendicular to the long axis of the MS was applied in the four mechanical tests: EM1: SS MS and a 1 mm transmucosal profile; EM2: titanium MS and a 1 mm transmucosal profile; EM3: SS MS and a 2 mm transmucosal profile; and EM4: titanium MS and a 2 mm transmucosal profile. RESULTS: The stress distributions in all mechanical tests were highest at the MS, especially at the MS-cortical bone interface. A greater stress concentration occurred in cortical bone measuring 1 mm thick than in the cortical bone measuring 2 mm thick. The MSs with a 2 mm transmucosal profile showed higher stress than those with a 1 mm transmucosal profile. CONCLUSION: The titanium alloy MSs showed higher stress fields and deflection voltages than the SS MSs at the same cortical bone thickness and with the same transmucosal profile. CLINICAL SIGNIFICANCE: From a mechanical perspective, this study showed the stress field generated in MSs with SS and titanium alloy (Ti) mechanical properties and surrounding bone. The stress distribution was concentrated at the MS, mainly at the interface with the cortical bone, and the difference between the stress values for the Ti and SS MSs was very small. Under this condition, the two types of MSs are suitable for orthodontic applications because their yield limits are much higher.

Clinical Outcome of an Impacted Maxillary Canine: From Exposition to Occlusion.

AIM: The aim is to report a case of impacted maxillary right canine successfully positioned into the occlusion line. BACKGROUND: Although the treatment of choice for an impacted canine is a combined surgical-orthodontic approach, there are differences in technique. The preorthodontic uncovering and autonomous eruption technique is a safe and predictable option for the treatment of palatally impacted maxillary canines in adolescents and adults as is the orthodontic creation of a space before minimal surgical exposure, the bonding of a small attachment (an eyelet), full-flap closure, and immediate traction. Although the mechanical management of impacted teeth is a routine task for most orthodontists, certain types of impaction can be frustrating. CASE DESCRIPTION: An 18-year-old adult patient presented for clinical examination with a mobile maxillary right deciduous canine, the absence of a maxillary right permanent canine, Angle Class I malocclusion, an overjet of 2.0 mm, an overbite of 3.0 mm, and rotated canine and left maxillary central and lateral incisors. Cephalometric measurements revealed a skeletal Class I relationship as well as upright maxillary incisors (1. NA = 18°) and mandibular incisors (1. NB = 16°, IMPA = 80°). The facial profile was concave. Clinically, a constricted maxillary arch was observed, and the patient had a nail-biting habit. CONCLUSION: The canine was aligned, leveled and positioned in the occlusion line. The esthetic, functional and periodontal results remained stable in the retention phase. CLINICAL SIGNIFICANCE: Various treatment strategies are available to treat impacted maxillary canines. The surgical, periodontal, and orthodontic considerations in the management of impacted canines must be clearly explained to the patient.

Stress Distribution Evaluation of the Periodontal Ligament in the Maxillary Canine for Retraction by Different Alveolar Corticotomy Techniques: A Three-dimensional Finite Element Analysis.

AIM: By using the finite element method (FEM), this study aimed to evaluate the effect of different corticotomy formats on the distribution and magnitude of stress on the periodontal ligament (PDL) during retraction of the maxillary canine. MATERIALS AND METHODS: A geometric model of the left hemi-jaw was created from computed tomography scan images of a dry human skull and loads were administered during distalization movement of the canine. Three trials were performed: (1) without corticotomy, (2) box-shaped corticotomy and perforations in the cortical bone of the canine (CVC) and (3) CVC and circular-shaped corticotomy in the cortical bone of the edentulous space of the first premolar. RESULTS: There was no difference in stress distribution among the different corticotomy formats. CONCLUSION: Different corticotomy formats used to accelerate orthodontic tooth movement did not affect stress distribution in the PDL during canine retraction. CLINICAL SIGNIFICANCE: From a mechanical perspective, the present study showed that the stress distribution on the PDL during canine retraction was similar in all the corticotomy formats. When using the Andrews T2 bracket, the PDL presented the highest levels of stress in the middle third of the PDL, suggesting that the force was near the center of resistance. Also, as bone weakening by corticotomies did not influence stress distribution, the surgical procedure could be simplified to a less aggressive one, focusing more on inflammatory cellular stimulation than on bone resistance. A simpler surgical act could also be performed by most orthodontists in their practices, enhancing postoperative response and reducing patient costs.

Stresses in the midpalatal suture in the maxillary protraction therapy: a 3D finite element analysis.

BACKGROUND: The aim of the present work was to evaluate the stress magnitudes and directions along the midpalatal suture in the maxillary protraction therapy. METHODS: The geometry of the maxilla and teeth were digitally reconstructed based on computer tomography images obtained from the skull of a girl in a mixed dentition stage with skeletal and dental class III malocclusion. An appliance commonly used for rapid palatal expansion (RPE) was also digitally modeled for anchorage of the protraction force and meshed for finite element analysis. The maxillary protraction was simulated applying 600 cN (300 cN for each side) directed 30° forward and downward to the maxillary occlusal plane. RESULTS: The principal stresses, through the force application, exhibited similar distribution patterns. A higher stress area was observed in the region of the midpalatal suture located in front of the incisive canal. All the sections showed vectors of compressive nature. CONCLUSIONS: Because of the compressive nature of the stresses distributed along the midpalatal suture in the maxillary protraction therapy simulation, which is opposite to the natural growth transversal tendency, maxillary expansion is advisable in clinical cases.

Effectiveness of varnish with CPP-ACP in prevention of caries lesions around orthodontic brackets: an OCT evaluation.

OBJECTIVE: To evaluate the in vitro efficiency of applying varnish containing casein phosphopeptide (CPP) and amorphous calcium phosphate (ACP) in prevention of caries lesions around orthodontic brackets. MATERIALS AND METHODS: For this purpose, brackets were bonded to the vestibular surface of bovine incisors, and eight groups were formed (n = 15) according to exposure of oral hygiene substances and enamel varnish: 1 (control) brushing only performed, 2 (control) brushing + use of mouth wash with fluoride, 3 Duraphat varnish application only (Colgate-Palmolive Ind. E Com. Ltda, São Paulo, SP, Brazil), 4 Duraphat + brushing, 5 Duraphat + brushing + mouth wash, 6 MI Varnish application (GC America, USA), 7 MI + brushing, and 8 MI + brushing + mouth wash. The experimental groups alternated between pH cycling and the procedures described and were kept in an oven at temperature of 37°C. Both brushing and immersion in solutions was performed in a time interval of 1 minute, followed by washing in deionized water three times a day for 28 days of experimentation. Afterwards, evaluation by optical coherence tomography (OCT) of the special type (Ganymede OCT/Thorlabs, Newton, USA) was performed. In each group, a scanning exam of the white spot lesion area (around the region where brackets were bonded) and depth measurement of caries lesions were performed. RESULTS: Groups 1 and 3 were shown to differ statistically from groups 5, 6, 7, and 8 (p = 0.000). MI Varnish was shown to be more effective in diminishing caries lesion depth, compared with Duraphat, irrespective of being associated with brushing and mouth wash, or not. LIMITATIONS: The major limitation of this study is that it is a study in which demineralization was obtained with the use of chemical products, and did not occur due to the presence of Streptococcus mutans and its acid byproducts. CONCLUSION: Application CPP-ACP-containing varnish irrespective of being associated with brushing and mouthwash, or not, reduced depth of caries lesions around orthodontic brackets.

Propulsores mandibulares para la corrección de maloclusiones de Clase II-1 subdivisión de Angle / Mandibular protraction appliance for the correction Angle Malocclusions Class II - 1 subdivision A

El tratamiento de maloclusiones de Clase II es un procedimiento de rutina en la práctica ortodóncica, y son de especial interés las que presentan subdivisiones, por su complejidad y factores de asimetrías que presentan. Hoy en día los aparatos de propulsion mandibular (APM) han ganado mayor aceptación por los clínicos debido a sus ventajas de acortar el tiempo de tratamiento general, lo que disminuye la necesidad de cooperación por parte de los pacientes. El aparato de protracción mandibular (APM IV) posee como ventaja que puede ser facilmente elaborado por el ortodoncista en su oficina. Sin embargo se hace importante entender cuáles son los efectos, beneficios y contraindicaciones de los propulsores antes de usarlos. El objetivo del presente artículo es describir cada uno de estos factores mediante un caso clínico.

The treatment of Class II malocclusions is a routine procedure in orthodontic practice, of special interest are the ones with subdivisions, because of their complexity and asymetric factors that they show. Nowadays the mandibular protraction appliances are gaining the acceptance of the clinicians because of their advantages in reducing the general treatment time and decreasing the need of patients´cooperation. The mandibular protraction appliance (MPA IV) has the advantage that it can be easily constructed by the orthodontist in his office. However it is important to understand which are the effects, benefits and contraindications of these appliances before using them. The aim of this article is to describe each of these factors through a case report

Propulsores mandibulares para la corrección de maloclusiones de Clase II-1 subdivisión de Angle / Mandibular protraction appliance for the correction Angle Malocclusions Class II - 1 subdivision A

El tratamiento de maloclusiones de Clase II es un procedimiento de rutina en la práctica ortodóncica, y son de especial interés las que presentan subdivisiones, por su complejidad y factores de asimetrías que presentan. Hoy en día los aparatos de propulsion mandibular (APM) han ganado mayor aceptación por los clínicos debido a sus ventajas de acortar el tiempo de tratamiento general, lo que disminuye la necesidad de cooperación por parte de los pacientes. El aparato de protracción mandibular (APM IV) posee como ventaja que puede ser facilmente elaborado por el ortodoncista en su oficina. Sin embargo se hace importante entender cuáles son los efectos, beneficios y contraindicaciones de los propulsores antes de usarlos. El objetivo del presente artículo es describir cada uno de estos factores mediante un caso clínico.(AU)

The treatment of Class II malocclusions is a routine procedure in orthodontic practice, of special interest are the ones with subdivisions, because of their complexity and asymetric factors that they show. Nowadays the mandibular protraction appliances are gaining the acceptance of the clinicians because of their advantages in reducing the general treatment time and decreasing the need of patients´cooperation. The mandibular protraction appliance (MPA IV) has the advantage that it can be easily constructed by the orthodontist in his office. However it is important to understand which are the effects, benefits and contraindications of these appliances before using them. The aim of this article is to describe each of these factors through a case report(AU)

Apicotomy: surgical management of maxillary dilacerated or ankylosed canines.

This clinical article reports a technique, apicotomy, for managing dilacerated or ankylosed canines. The records of 3 patients successfully treated with apicotomy are presented. Orthodontists observe clinically significant incidences of impacted maxillary canines in their daily practices. Several procedures have been described to bring an ankylosed, impacted tooth into occlusion. Luxation is the most widely used solution, but there are risks involved with that approach, and the success rate is low. Surgical repositioning has also been used, but morbidity is high, and the aggressiveness of the procedure might also contraindicate it. Ankylosis might be related to the anatomic position of the canine's root apex and its adjacent anatomic structures. Apicotomy is a guided fracture of a canine root apex, followed by its orthodontic traction. It is a conservative surgical alternative for treating impacted canines with dilacerations or apical root ankylosis.

Evaluation of skeletal and dental asymmetries in Angle Class II subdivision malocclusions with cone-beam computed tomography.

INTRODUCTION: The purpose of this study was to determine whether Angle Class II subdivision malocclusions have skeletal or dental asymmetries between the Class II and Class I sides. METHODS: A sample of 54 untreated Angle Class II subdivision patients with pretreatment photos and cone-beam computed tomography (CBCT) scans was used. The photos were used to identify the Class II subdivision malocclusion and to record the amount of crowding per quadrant. Landmarks were plotted on each CBCT volume so that direct 3-dimensional measurements could be made to compare the positions and dimensions of the skeletal and dental structures on the Class II side vs the Class I side. RESULTS: Significant differences were found for 2 skeletal measurements: the position of the maxilla relative to the cranial base, and the mandibular dimension from the mandibular foramen to the mental foramen. Statistically significant dental differences were found for the position of the mandibular first molars and canines in relation to the maxilla and the mandible. Statistically significant differences were found for the maxillary first molars and canines in relation to the mandible. CONCLUSIONS: There were significant skeletal and dental differences between the Class I and Class II sides. The dental asymmetries accounted for about two thirds of the total asymmetry.

Expansão maxilar rápida X expansão maxilar lenta: considerações clínicas / Rapid maxillary expansion X Slow maxillary: clinical considerations

A recuperação da discrepância transversal da maxila mostra-se indispensável para o tratamento adequado de diversos tipos de má oclusão. Diferentes aparelhos expansores têm sido descritos na literatura com a finalidade de expandir a maxila, sendo que esses podem resultar em expansão maxilar lenta (EML) ou rápida (EMR). O objetivo deste trabalho é discutir as considerações clínicas da EML e da EMR. Os dois pacientes avaliados utilizaram expansor fixo como preconizado por Haas, porém, foram submetidos a diferentes protocolos de ativação. Apesar das diferenças clínicas apresentadas, tanto a EMR quanto a EML mostraram-se eficientes na correção da mordida cruzada posterior na dentição mista.

Metal and ceramic bracket effects on human buccal mucosa epithelial cells.

OBJECTIVE: To test the null hypothesis that metal and ceramic brackets have no effect on the epithelial cells of the buccal mucosa. MATERIALS AND METHODS: Two metal and two ceramic brackets were bonded in 21 individuals of both sexes. With the use of liquid-based exfoliative cytology, morphometric and morphologic changes in buccal mucosa cells adjacent to these brackets were determined and were compared at three time points: baseline (T0), 60 days after placement (T1), and 30 days after removal of the brackets (T2). RESULTS: A decrease in nuclear area and an increase in cytoplasmic area occurred in the buccal mucosa cells adjacent to the brackets at T1 (P < .01). At T2, this altered morphometry persisted only in cells adjacent to the metal brackets, although to a lesser degree than at T1 (P < .01). A greater decrease in nuclear area was noted in cells adjacent to the metal brackets than in those next to the ceramic brackets (P < .01). At T0, the proportions of surface and subsurface cells were similar, but at T1, a predominance of surface cells was observed (P < .05). At all time points, smears of cells appeared normal or normal with some inflammatory changes. CONCLUSION: The hypothesis is rejected. Placement of metal and ceramic brackets in the buccal cavity induces cellular alterations. These alterations do not suggest malignancy.

Estudo da função muscular peribucal, do grau de inclinação vestíbulo-lingual e da discrepância de modelo dos incisivos inferiores permanentes em crianças respiradoras nasais e bucais com oclusão normal e má oclusão de Classe I / A perioral muscles activity, buccal-lingual inclination and space discrepancy of the lower incisors study, in mouth or nasal breathing children with normal or Class I malocclusion

O objetivo deste trabalho foi verificar a existência de correlação entre o modo respiratório bucal, o comportamento dos músculos orbicular inferior da boca e mentoniano e a determinação de características oclusais específicas, na região anterior do arco dentário inferior. A amostra constituiu-se de 88 crianças brasileiras, leucodermas, sendo 49 do gênero masculino e 39 do gênero feminino, com média de idade de 6 anos e 11 meses, dividida em 4 subgrupos, portadores de: oclusão normal e modo respiratório nasal (ONRN); oclusão normal e modo respiratório bucal (ONRB); má oclusão de Classe I e modo respiratório nasal (CLIRN) e má oclusão de Classe I e modo respiratório bucal (CLIRB). Foram realizados 22 testes eletromiográficos, avaliação do grau de inclinação vestíbulo-lingual (FMIA) e da discrepância de modelo (DM) dos incisivos inferiores permanentes. Após terem sido submetidos à análise estatística os resultados indicaram que, quando comparados os subgrupos, não houve diferença estatisticamente significativa para as variáveis dentárias e para a maioria das variáveis eletromiográficas avaliadas. Desta forma, a alteração do modo respiratório não pode ser relacionada às características oclusais e aos comportamentos musculares estudados