Reconsidering the role of nasolabial angle in premolar extraction decision-making: A case-series study.

OBJECTIVES: To evaluate the impact of changes in upper incisor inclination and position on the alteration of the nasolabial angle (NLA) in a series of cases involving the extraction of four first premolars. MATERIALS AND METHODS: The study included 41 patients who underwent orthodontic treatment with premolar extractions. The patients were divided into two groups based on their pretreatment NLA values: Group 1 (NLA ≤ 100°) and Group 2 (NLA > 100°). Measurements of NLA, U1.NA and U1-NA were obtained before and after treatment and U1-Ls pretreatment measure was registered. Statistical analyses were performed to compare the differences in NLA, U1.NA and U1-NA between the two groups and to evaluate the influence of these variables added to U1-Ls (T1) on NLA changes. RESULTS: The results showed that Group 1 exhibited significant changes in NLA, while Group 2 did not. However, both groups showed significant changes in U1.NA and U1-NA. In Group 1, 80% of the individuals presented an increase in NLA and 20% no changes. In Group 2, 10% presented a decrease, 57% no changes and 33% an increase in NLA values. Multiple linear regression analysis indicated that the group factor had a statistically significant influence on NLA variation. Additionally, in Group 2, a negative correlation was observed between changes in U1.NA and NLA. CONCLUSIONS: The findings suggest that individuals with higher pretreatment NLA values tend to maintain their NLA values even after the correction of upper incisor inclination.

Class II subdivision treatment and stability with asymmetric Herbst appliance: A case report.

Non-surgical treatment of Class II subdivision may involve complex mechanics or asymmetric tooth extraction in its resolution. This report demonstrates the result and the short-term stability of Class II subdivision treated with asymmetrically installed Herbst appliance followed by conventional fixed orthodontic appliance. The approach allowed the correction of the unilateral Class II molar relationship and increased overjet, as well as the deviation of dental midlines, with improvement in lip posture and facial profile. The results remained stable two years after treatment, confirming the treatment success.

Malocclusion or laterorhinia: Which one impacts aesthetic facial perception the most?

INTRODUCTION: This study aimed to evaluate the perception of facial attractiveness when nose and teeth, together or isolated, present different degrees of disharmony. The secondary objective was to compare the perception of laypersons with that of dentists. MATERIALS AND METHODS: This cross-sectional observational study included 112 individuals (58 laypersons and 54 dentists) that evaluated 6 manipulated images of the face of the same model, scoring their attractiveness using 10 cm Visual Analogue Scales (VAS), with least and most attractive at the left and right anchors, respectively. The images contained manipulations performed only on the nose (laterorhinia) and mouth (misaligned teeth), as follows: (1) standard photograph, with symmetrical nose + aligned teeth; (2) 2 mm nasal deviation + aligned teeth; (3) 4 mm nasal deviation + aligned teeth; (4) symmetrical nose + misaligned teeth; (5) 2 mm nasal deviation + misaligned teeth and (6) 4 mm nasal deviation + misaligned teeth. We used the repeated measures ANOVA test and Tukey's post-test for intra-group comparison of the images. The independent t-test was used for inter-group comparison of each image. RESULTS: In the laypersons' group, the highest grades were given to images with aligned teeth and the lowest to misaligned teeth (smallest mean difference = 2.88 cm). For this group, there was no statistically significant difference (P-values ranged from .988 to 1.000) between scores of the three images in which teeth were aligned (range of 7.70-7.78 cm). In the group of dentists, highest grades were given to images with aligned teeth and the lowest to misaligned teeth. Difference between images 3 and 4 was not statistically significant (P = .204). All other differences between any image of straight teeth and any image with misaligned teeth were significant and the smallest mean difference between the two groups of images was 1.87 (P = .039). However, in the images with aligned teeth, there was also a statistically significant difference with higher scores to the images with symmetrical nose in contrast with those with significant laterorhinia (mean difference = 1.03 cm). CONCLUSION: Teeth disharmonies had a more negative impact on the aesthetic perception of the face than did nose deviations, for both dentists and laypersons.

Redirection of palatally ectopic maxillary canines: Case report and proposition of an interceptive sequential guideline.

The eruptive deviation of the permanent maxillary canine must be identified early, at the beginning of the second transitional period of the mixed dentition. Acting at this moment is fundamental for its spontaneous redirection and eruption. The aim of the paper is to present a case where the extraction of the deciduous canines was the choice for redirecting the maxillary permanent canines with eruptive palatal deviation, as well as to suggest a sequence of procedures for diagnosis and choice of treatment. The success of deciduous canine extraction in redirecting the ectopic permanent canines is discussed in this case, as well as aspects that might lead to failure. Still, it highlights the importance of computed tomography for choosing conservative treatment or traction, including it in the sequential guideline for acting in these cases.

Pain perception and expectation related to interradicular mini-implants insertion: a systematic review and meta-analysis.

OBJECTIVES: The aim of this systematic review was to compare the expectation and perception of pain reported by patients before and after the installation of interradicular mini-implants. MATERIALS AND METHODS: Electronic search was performed in six databases. Inclusion criteria were randomized controlled trials (RCTs) or non-randomized controlled clinical trials (nRCTs); studies using mini-implants in the interradicular region; assessment of pain intensity by visual analogue or numerical scale. The risk of bias assessment was based on the Rob 2 tool and Robins-I. RESULTS: A total of 1566 articles were retrieved, and 21 met the eligibility criteria. Six were classified as high risk, one as critical and the other one as uncertain, according to the Robins-I tool. In articles evaluated by the Rob2 tool, ten were classified as serious risk and three as moderate risk. A meta-analysis was also performed. Weighted means were calculated among the studies using the random-effects model and forest plots were generated. Heterogeneity was assessed through the Q test and I2 statistics. It was observed, with moderate evidence, that on a scale of 0 to 10, the pain expectation (effect size 4.75) is higher than that effectively pain generated by the procedure (effect size 1.94). CONCLUSION: Pain expectation was greater than that actually generated by the procedure, being almost non-existent 7 days postoperatively. CLINICAL RELEVANCE: This study may help the clinician to reassure the patient regarding the sensations that could be experienced during and after the installation.

Pharyngeal airway subdivisions in 3-dimensional analysis: Differences between anterior and posterior anatomic boundaries.

INTRODUCTION: This study aimed to evaluate if there were differences between anterior and posterior anatomic boundaries used for the 3-dimensional determination of pharyngeal airway. METHODS: The sample included 150 cone-beam computed tomography scans from healthy patients divided according to (1) age: 6-11, 12-16, and ≥16 years; (2) sex: female and male; (3) anteroposterior skeletal pattern: Class I, II, and III; (4) vertical pattern: brachyfacial, mesofacial, and dolichofacial; and (5) craniocervical inclination (CCI): natural head posture, head flexion, and head extension. Anatomic regions were created to determine the correspondences between structures anteriorly and posteriorly to the pharyngeal airway. RESULTS: The location of the epiglottis, vallecula, hyoid, C2, and C3 were statistically different according to the CCI, and the location of vallecula, C3, and C4 were different according to sex. However, no statistically significant differences were observed between the frequencies of anterior and posterior anatomic region locations among age and different anteroposterior and vertical skeletal patterns. Posterior landmarks tend to be located below the anterior ones; consequently, the anatomic subregion they define will also be located below. CONCLUSIONS: Anterior and posterior structures and vertical and anteroposterior skeletal patterns may determine upper airway limits regardless of age. However, the studies must be paired according to sex, and CCI must be standardized.

Influence of clinical and demographic factors on the oral health-related quality of life of patients with cleft lip and palate undergoing orthodontic treatment: a systematic review and meta-analysis.

OBJECTIVE: The purpose of this study was to evaluate the influence of orthodontic treatment on the oral health-related quality of life (OHRQoL) of patients with cleft lip and palate. SEARCH METHODS: Electronic searches were conducted in Pubmed, Scopus, Web of Science, Cochrane Library, VHL, and OpenGrey databases, completed in January 2021. SELECTION CRITERIA: Cross-sectional and longitudinal observational studies that presented an assessment of OHRQoL in cleft patients undergoing orthodontic treatment were included, according to PRISMA guidelines. Contacts via email were made with authors, to clarify inaccuracies or request additional data. DATA COLLECTION AND ANALYSIS: The entire process was accomplished by two authors, in case of disagreement, a third author mediated the discussion until there was a consensus. Risk assessment was performed by the Fowkes and Fulton qualifier, and the quality of evidence, assessed by the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) tool. A meta-analysis was performed considering the domains combined into three large groups (physical, psychological, and social). The questionnaires were standardized as to the scores and their direction. RESULTS: A total of 3822 studies were retrieved. After excluding duplicates, the titles and abstracts of the remaining articles were analysed. Twenty-eight articles were read in full; 13 met the eligibility criteria; 12 articles showed sufficient methodological quality and 7 were included in the quantitative assessment. The included studies were published between 2011 and 2019. The samples comprised 19 to 183 patients of both sexes. GRADE showed low evidence when compared to the control group, sexes, age, and types of cleft and very low evidence among longitudinal articles. CONCLUSIONS: The OHRQoL is lower in orthodontic patients with cleft than in those without. The OHRQoL of patients with cleft undergoing orthodontic treatment is not influenced by gender or age group, considering children and adolescents, but it is influenced by the type of cleft. The OHRQoL of patients with CLP does not undergo significant changes during orthodontic treatment. LIMITATIONS: The variety of instruments for measuring OHRQoL rendered meta-analysis difficult. REGISTRATION: PROSPERO database number CRD42017054764.

Therapeutic effects of botulinum toxin type A in subjects with gummy smile: A longitudinal sEMG approach.

OBJECTIVE: To evaluate the response of the myoelectric activity of levator labii superioris (LLS), levator labii superioris alaeque nasi (LLSAN), and minor zygomatic (Zm) muscles in individuals with gummy smile, volunteers to botulinum toxin type A (BTX-A) application, with a follow-up of 6 months. MATERIALS AND METHODS: Thirteen individuals were submitted to clinical evaluation and photographic records to monitor the variations of the gingival display (GD) during posed smile. The recording of the surface electromyography (sEMG) signal of muscles studied was performed in three tasks: posed smile (PS), upper lip elevation (ULE) and nose wing elevation (NWE). The root-mean-square value, an amplitude sEMG signal parameter, was extracted from the sEMG signals. One and three-way ANOVA were applied, and the level of significance set at 5%. RESULTS: There were significant differences (P<0.05) in the sEMG signal activity from the control condition (before BTX-A application - T0) to the 8th week of follow up, which was accompanied by clinical evaluation for the gingival display (P<0.05). The peak of the reduction in sEMG signals occurred 2 weeks after T0 for all the studied tasks, with the exception of the left hemiface in the PS, which showed a peak of reduction 4 weeks after T0. CONCLUSIONS: BTX-A led to a decrease in the sEMG signal amplitude over 2 to 4 weeks after application in the muscles, although differently concerning each hemiface when recruited to perform other mouth tasks. During the PS, the recruitment level of the upper lip elevator muscles was compatible with the clinical response obtained in the follow-up period in this study, which corroborates the sEMG assessment to clinical data.

Tomographic analysis of midpalatal suture prior to rapid maxillary expansion.

INTRODUCTION: In Orthodontics and Facial Orthopedics, the timing of treatment onset may be critical and individual analysis should be applied to promote a favorable treatment planning. In this study, individual analysis of midpalatal suture (MS) and palatal measurements were performed in teenagers and young adult patients treated with rapid maxillary expansion (RME). DESCRIPTION: Twenty-six patients submitted to RME with a tooth-supported appliance (Hyrax) were evaluated. The inclusion criteria were: minimum age of 14 years, presenting all posterior teeth, diagnosed with transverse maxillary discrepancy, and with a clinical indication for maxillary expansion. The pretreatment CBCT scans of these patients were assessed to obtain the stages of MS maturation (MSM); density ratio (MSD); and palatal length, thickness (anterior, intermediate and posterior) and sagittal area. RESULTS: The maturation stages present were C, D or E; the density ranged from 0.6 to 1, and lower density (MSD < 0.75) and higher density (MSD ≥ 0.75) groups were determined. Individuals with higher MSD presented smaller sagittal area, compared to the lower density group. Individuals in D and E MSM stages presented smaller sagittal area and intermediate thickness, compared to stage C. CONCLUSIONS: Smaller palatal sagittal area was observed in the high MSD groups and in the stages D and E of MSM.

Chromatic analysis of orthodontic resin bonding agents exposed to different antiseptic mouthrinses.

OBJECTIVE: To assess the color of different orthodontic resin bonding agents exposed to three antiseptic mouthrinses for a prolonged time interval (10-year aging simulation). METHODS: 160 specimens were distributed into four groups, according to the orthodontic resin bond agent (Concise, Transbond XT, Transbond Plus Color Change, and Natural Ortho). Each group was exposed to different antiseptic mouthrinses: alcohol-based (Listerine®), alcohol-free (Oral-B®), chlorhexidine (Periogard®) and distilled water as the control. Specimens were submitted to two cycles of staining and artificial aging. Color was evaluated by means of a digital spectrophotometer at the beginning of the experiment and after every cycle. The system used to assess color changes was the CIE L*a*b*. Data was analyzed using the ANOVA and Tukey post-hoc test. RESULTS: After simulation of 10 years of aging, Transbond XT and Natural Ortho composites presented no statistically significant differences in ∆E when exposed to different mouthrinses. The Concise composite specimens exposed to alcohol-free mouthrinse presented a significant difference when compared with specimens from the same group exposed to other antiseptic mouthrinses. Transbond Plus Color Change specimens exposed to chlorhexidine mouthrinse and to alcohol-containing mouthrinse presented a significant difference when compared with the specimens from the group exposed to water and alcohol-free antiseptic. CONCLUSION: All orthodontic resin bonding agents tested presented clinically perceptible color changes when exposed to at least one of the mouthrinses, except for the Natural Ortho composite. The Concise composite exposed to the alcohol-free solution was the resin that presented the highest color change values.

Hyperextension of the head versus cervical vertebrae morphology in mouth and nasal breathers: a preliminary study

Objective: This study aimed to compare through cone-beam computed tomography (CBCT) the morphology of the cervical vertebrae atlas (C1) and axis (C2) in mouth breathers (MB) and nose breathers (NB), correlating them with the head and neck postures of the two groups. Materials and Methods: CBCT images of 36 subjects aged 11 to 22 years were evaluated using the InVivo Dental 5.1 (Anatomage, San Jose, California) software. The following measurements were used to assess C1 and C2 morphology: posterior height, anterior height, length, and volume. The craniocervical angle (NSL/OPT) was used to evaluate head posture concerning the neck. Results: The posterior height, length, and volume of C1 and C2 were lower in the MB group, but only the posterior size was significantly shorter than the NB group (C1, p=0.01 / C2, =0.05). Mouth breathers also showed a considerably higher craniocervical angle (p=0.04). Spearman test showed a significant positive correlation between C1 and C2 length and craniocervical angle (C1, =0.629, p=0.005 / C2, =0.665, p=0.003). Conclusion: The mouth breathers showed an increased craniocervical angle and decreased posterior height of the C1 vertebra concerning nasal breathers. The hyperextension of the head present is positively correlated with the length of the vertebra.

Objetivo: Este estudo teve como objetivo comparar por meio da tomografia computadorizada de feixe cônico (TCFC) a morfologia do atlas das vértebras cervicais (C1) e do eixo (C2) em respiradores orais (MB) e nasais (RN), correlacionando-os com a cabeça e posturas do pescoço dos dois grupos. Materiais e Métodos: Imagens de CBCT de 36 indivíduos com idades entre 11 e 22 anos foram avaliadas usando o software InVivo Dental 5.1 (Anatomage, San Jose, Califórnia). As seguintes medidas foram usadas para avaliar a morfologia de C1 e C2: altura posterior, altura anterior, comprimento e volume. O ângulo craniocervical (NSL/OPT) foi utilizado para avaliar a postura da cabeça em relação ao pescoço. Resultados: A altura posterior, comprimento e volume de C1 e C2 foram menores no grupo MB, mas apenas o tamanho posterior foi significativamente menor que o grupo RN (C1, p=0,01 / C2, =0,05). Os respiradores orais também apresentaram um ângulo craniocervical consideravelmente maior (p=0,04). O teste de Spearman mostrou correlação positiva significativa entre comprimento de C1 e C2 e ângulo craniocervical (C1, =0,629, p=0,005 / C2, =0,665, p=0,003). Conclusão: Os respiradores orais apresentaram aumento do ângulo craniocervical e diminuição da altura posterior da vértebra C1 em relação aos respiradores nasais. A hiperextensão da cabeça presente está positivamente correlacionada com o comprimento da vértebra.

Tomographic analysis of midpalatal suture prior to rapid maxillary expansion

ABSTRACT Introduction: In Orthodontics and Facial Orthopedics, the timing of treatment onset may be critical and individual analysis should be applied to promote a favorable treatment planning. In this study, individual analysis of midpalatal suture (MS) and palatal measurements were performed in teenagers and young adult patients treated with rapid maxillary expansion (RME). Description: Twenty-six patients submitted to RME with a tooth-supported appliance (Hyrax) were evaluated. The inclusion criteria were: minimum age of 14 years, presenting all posterior teeth, diagnosed with transverse maxillary discrepancy, and with a clinical indication for maxillary expansion. The pretreatment CBCT scans of these patients were assessed to obtain the stages of MS maturation (MSM); density ratio (MSD); and palatal length, thickness (anterior, intermediate and posterior) and sagittal area. Results: The maturation stages present were C, D or E; the density ranged from 0.6 to 1, and lower density (MSD < 0.75) and higher density (MSD ≥ 0.75) groups were determined. Individuals with higher MSD presented smaller sagittal area, compared to the lower density group. Individuals in D and E MSM stages presented smaller sagittal area and intermediate thickness, compared to stage C. Conclusions: Smaller palatal sagittal area was observed in the high MSD groups and in the stages D and E of MSM.

RESUMO Introdução: Em Ortodontia e Ortopedia Facial, o momento de início do tratamento pode ser crítico, e uma análise individual deve ser aplicada para promover um planejamento de tratamento favorável. No presente estudo, foram realizadas a avaliação individualizada da sutura palatina mediana (SPM) e medições no palato de adolescentes e adultos jovens tratados com expansão rápida da maxila (ERM). Descrição: Foram avaliados vinte e seis pacientes submetidos à ERM com aparelho dentossuportado (Hyrax). Os critérios de inclusão foram: idade mínima de 14 anos, apresentando todos os dentes posteriores, diagnosticado com discrepância transversa da maxila e com uma indicação clínica para expansão maxilar. A tomografia computadorizada de feixe cônico (TCFC) pré-tratamento desses pacientes foi avaliada para obter os estágios de maturação da SPM (MSPM), densidade da SPM (DSPM), comprimento do palato, espessura (anterior, intermediária e posterior) e área sagital. Resultados: Os estágios de maturação presentes foram C, D ou E; a densidade variou de 0,6 a 1, e foram determinados grupos de baixa (DSPM < 0,75) e alta densidade (DSPM ≥ 0,75). Indivíduos com maior DSPM apresentaram menor área sagital, em comparação com o grupo de densidade mais baixa. Indivíduos nos estágios D e E de MSPM apresentaram menor área sagital e espessura intermediária, comparados aos indivíduos no estágio C. Conclusão: Uma menor área sagital palatina foi observada nos grupos de alta DSPM e nos estágios D e E de MSPM.

Chromatic analysis of orthodontic resin bonding agents exposed to different antiseptic mouthrinses

ABSTRACT Objective: To assess the color of different orthodontic resin bonding agents exposed to three antiseptic mouthrinses for a prolonged time interval (10-year aging simulation). Methods: 160 specimens were distributed into four groups, according to the orthodontic resin bond agent (Concise, Transbond XT, Transbond Plus Color Change, and Natural Ortho). Each group was exposed to different antiseptic mouthrinses: alcohol-based (Listerine®), alcohol-free (Oral-B®), chlorhexidine (Periogard®) and distilled water as the control. Specimens were submitted to two cycles of staining and artificial aging. Color was evaluated by means of a digital spectrophotometer at the beginning of the experiment and after every cycle. The system used to assess color changes was the CIE L*a*b*. Data was analyzed using the ANOVA and Tukey post-hoc test. Results: After simulation of 10 years of aging, Transbond XT and Natural Ortho composites presented no statistically significant differences in ∆E when exposed to different mouthrinses. The Concise composite specimens exposed to alcohol-free mouthrinse presented a significant difference when compared with specimens from the same group exposed to other antiseptic mouthrinses. Transbond Plus Color Change specimens exposed to chlorhexidine mouthrinse and to alcohol-containing mouthrinse presented a significant difference when compared with the specimens from the group exposed to water and alcohol-free antiseptic. Conclusion: All orthodontic resin bonding agents tested presented clinically perceptible color changes when exposed to at least one of the mouthrinses, except for the Natural Ortho composite. The Concise composite exposed to the alcohol-free solution was the resin that presented the highest color change values.

RESUMO Objetivo: Avaliar a cor de diferentes resinas ortodônticas expostas a três enxaguantes bucais, por um intervalo de tempo prolongado (simulação de 10 anos de envelhecimento). Métodos: 160 espécimes foram distribuídos em quatro grupos, de acordo com a resina de colagem ortodôntica (Concise, Transbond XT, Transbond Plus Color Change e Natural Ortho). Cada grupo foi exposto a diferentes tipos de enxaguantes bucais: à base de álcool (Listerine®), isento de álcool (Oral-B®), clorexidina (Periogard®) ou água destilada, como controle. Os espécimes foram submetidos a dois ciclos de manchamento e envelhecimento artificial. A cor foi avaliada por meio de um espectrofotômetro digital no início do experimento e após cada ciclo. O sistema utilizado para avaliar as alterações de cor foi o CIE L*a*b*. Os dados foram analisados utilizando-se o teste ANOVA e o teste post-hoc de Tukey. Resultados: Após a simulação de 10 anos de envelhecimento, as resinas Transbond XT e Natural Ortho não apresentaram diferenças estatisticamente significativas no ∆E, quando expostas a diferentes enxaguantes bucais. Os espécimes do grupo Concise expostos ao enxaguante bucal sem álcool apresentaram diferença significativa quando comparados aos espécimes do mesmo grupo expostos aos outros enxaguantes bucais. Os espécimes do grupo Transbond Plus Color Change expostos à clorexidina e ao enxaguante bucal à base de álcool apresentaram diferença significativa quando comparados aos espécimes dos grupos expostos à água e ao enxaguante bucal sem álcool. Conclusão: Todas as resinas ortodônticas avaliadas apresentaram alterações de cor clinicamente perceptíveis quando expostas a pelo menos um dos enxaguantes bucais, com exceção da resina ortodôntica Natural Ortho. A resina Concise exposta à solução isenta de álcool foi a que apresentou os maiores valores de alteração de cor.

Remnant adhesive flash in orthodontic bonding systems with different characteristics

Introduction: Excess of adhesive around brackets negatively impact oral health of orthodontic patients. Objective: Evaluate the influence of orthodontic bonding system in removal of adhesive flash around orthodontic brackets. Methods: Based on their characteristics, four orthodontic bonding systems were selected: lightcuring adhesive (G1 - TransbondTM XT); pink pigmented light-curing adhesive (G2- TransbondTM Plus Color Change); resin-modified glass ionomer cement (G3 - FujiOrthoTM LC); and auto-curing adhesive (G4 - ConciseTM). For each group (n=10), a single operator placed metal brackets on bovine teeth (n=40) and used an explorer tip to visually remove flash excess. After curing / setting, the sampleswere taken to a stereomicroscope and the Axio Vision 4.4 software was used to measure the area of remnant adhesive flash around each bracket. The quantitative data obtained was analyzed by the Kruskal-Wallis and Dunn's post hoc test at = 0.05. Results: The results show that the resin-modified glass ionomer cement (G3) had a larger area of remnant material than the other groups. There was no statistical difference between the other groups (G1, G2, and G4), independently of pigmentation or curing technique. Conclusion: It was concluded that the use of a resin-modified glass ionomer cement results in a larger area of remnant flash excess, which can negatively impact oral health. Pigmentation and curing technique did not influence on remnant flash excess.

Introdução: O excesso de material de colagem que permanece ao redor dos bráquetes impacta negativamente a saúde bucal dos pacientes ortodônticos. Objetivo: Avaliar a influência dos sistemas de colagem ortodônticos na remoção de excesso de adesivo ao redor de bráquetes. Métodos: Baseado em suas características, quatro sistemas de colagem ortodônticos foram selecionados: adesivo fotopolimerizável (G1 ­ TransbondTM XT); adesivo fotopolimerizável com pigmentação rosa (G2 - TransbondTM Plus Color Change); cimento de ionômero de vidro reforçado com resina (G3 - FujiOrthoTM LC); e adesivo autopolimerizável (G4 - ConciseTM). Para cada grupo (n=10), um único operador posicionou os bráquetes em dentes bovinos (n=40) e utilizou uma sonda exploradora para remoção visual do excesso de material de colagem. Após a polimerização / tempo de cura, as amostras foram levadas ao estereomicroscópio e o software Axio Vision 4,4 foi utilizado para mensurar a área de excesso de adesivo remanescente ao redor de cada bráquete. Os dados quantitativos obtidos foram analisados pelos testes de Kruskal-Wallis e post-hoc de Dunn em significância de = 0,05. Resultados: O cimento de ionômero de vidro reforçado por resina (G3) apresentou a maior área de remanescente de excesso. Não houve diferença estatisticamente significativa entre os demais grupos (G1, G2 e G4), independente da pigmentação ou do método de polimerização. Conclusão: O uso de cimento de ionômero de vidro reforçado por resina resulta em maior área de excesso remanescente, o que pode impactar negativamente a saúde bucal. A pigmentação e o método de polimerização não influenciaram no excesso de material remanescente.

Analysis of the middle region of the pharynx in adolescents with different anteroposterior craniofacial skeletal patterns.

OBJECTIVE: To assess the volume and morphology of the middle region of the pharynx (MRP) in adolescents with different anteroposterior craniofacial skeletal patterns. METHODS: One hundred twenty-six patients (56 male and 70 female), who had cone-beam computed tomography (CBCT) within their records, were selected for this cross-sectional study. Participants were classified, according to their ANB angle value, in Class I (1o ≤ ANB ≤ 3o), Class II (ANB > 3o) and Class III (ANB < 1o). The total volume (tV), minimum axial area (AxMin) and morphology of the MRP and its subdivisions - velopharynx (VP) and oropharynx (OP) - were characterized by CBCT and 3-dimensional image reconstruction software. Intergroup comparisons were performed by ANOVA and Tukey post-hoc tests. Correlations between tV and Axmin with the ANB angle values were tested using linear regression analysis, considering sex as covariable. RESULTS: Statistically significant difference between groups were observed in tV only for the VP region; Class II individuals presented significantly lower tV (6863.75 ± 2627.20 mm3) than Class III subjects (9011.62 ± 3442.56 mm3) (p< 0.05). No significant differences were observed between groups for any other variable assessed, neither in MRP nor in the OP region (p> 0.05). A significant negative correlation was evidenced between tV and Axmin and the ANB angle values; sexual dimorphism was observed for some variables. CONCLUSIONS: Class II subjects have smaller tV in the VP region. tV and Axmin tend to decrease in all evaluated regions when the ANB angle values increase.

Analysis of the middle region of the pharynx in adolescents with different anteroposterior craniofacial skeletal patterns

ABSTRACT Objective: To assess the volume and morphology of the middle region of the pharynx (MRP) in adolescents with different anteroposterior craniofacial skeletal patterns. Methods: One hundred twenty-six patients (56 male and 70 female), who had cone-beam computed tomography (CBCT) within their records, were selected for this cross-sectional study. Participants were classified, according to their ANB angle value, in Class I (1o ≤ ANB ≤ 3o), Class II (ANB > 3o) and Class III (ANB < 1o). The total volume (tV), minimum axial area (AxMin) and morphology of the MRP and its subdivisions - velopharynx (VP) and oropharynx (OP) - were characterized by CBCT and 3-dimensional image reconstruction software. Intergroup comparisons were performed by ANOVA and Tukey post-hoc tests. Correlations between tV and Axmin with the ANB angle values were tested using linear regression analysis, considering sex as covariable. Results: Statistically significant difference between groups were observed in tV only for the VP region; Class II individuals presented significantly lower tV (6863.75 ± 2627.20 mm3) than Class III subjects (9011.62 ± 3442.56 mm3) (p< 0.05). No significant differences were observed between groups for any other variable assessed, neither in MRP nor in the OP region (p> 0.05). A significant negative correlation was evidenced between tV and Axmin and the ANB angle values; sexual dimorphism was observed for some variables. Conclusions: Class II subjects have smaller tV in the VP region. tV and Axmin tend to decrease in all evaluated regions when the ANB angle values increase.

RESUMO Objetivo: avaliar o volume e a morfologia da porção média da faringe (PMF) em adolescentes com diferentes padrões esqueléticos no sentido anteroposterior. Método: para esse estudo transversal, foram selecionados cento e vinte e seis pacientes (56 homens e 70 mulheres) que tinham tomografia computadorizada de feixe cônico (TCFC) em seus registros. Os participantes foram classificados de acordo com o valor do ângulo ANB, em Classe I (1o ≥ ANB ≤ 3o), Classe II (ANB > 3o) e Classe III (ANB < 1o). O volume total (Vt), a área axial mínima (AxMin) e a morfologia da PMF e de suas subdivisões - velofaringe (VF) e orofaringe (OF) - foram avaliados na TCFC e em software de reconstrução tridimensional (3D) de imagens. As comparações intergrupos foram realizadas por meio dos testes ANOVA e post-hoc de Tukey. As correlações entre os valores de Vt e Axmin das vias aéreas com os valores do ângulo ANB foram testadas por meio de análise de regressão linear, considerando-se o sexo como uma covariável. Resultados: diferença estatisticamente significativa entre os grupos foi observada apenas no Vt da VF; indivíduos Classe II apresentaram Vt significativamente menor (6.863,75 ± 2.627,20 mm3) do que indivíduos Classe III (9.011,62 ± 3.442,56 mm3) (p< 0,05). Não foram observadas diferenças significativas entre os grupos em nenhuma outra variável avaliada, nem na PMF, nem na OF (p> 0,05). Foi evidenciada uma correlação negativa significativa entre Vt e Axmin e os valores do ângulo ANB; dimorfismo sexual foi observado para algumas variáveis. Conclusões: indivíduos Classe II apresentam o menor Vt da VF. O Vt e a Axmin tenderam a diminuir quando os valores do ângulo ANB aumentaram, em todas as regiões avaliadas.

Surface morphologic evaluation of orthodontic bonding systems under conditions of cariogenic challenge.

Orthodontic bonding systems are submitted to demineralization and remineralization dynamics that might compromise their surface smoothness, and favor biofilm aggregation and caries development. The aim of the present study was to evaluate the effects of a cariogenic challenge model (in vitro pH-cycling model) on the surface roughness and topography of 3 bonding materials: Transbond™ XT (XT), Transbond™ Plus Color Change (PLUS) and Fuji Ortho™ LC (FUJI), by means of Atomic Force Microscopy (AFM). Six specimens with standardized dimensions and surface smoothness were fabricated per group, and the materials were manipulated in accordance with the manufacturers' instructions. No polishing was necessary. AFM tests were performed before and after pH-cycling, taking 3 readouts per specimen. The roughness results (Ra) were obtained at nanometric levels (nm) and surface records were acquired in two- and three-dimensional images of height and lock-in phase of the material components. The surfaces of all groups analyzed in the study were morphologically altered, presenting images suggestive of matrix degradation and loss of matrix-load integrity. FUJI presented the greatest increase in surface roughness, followed by XT and PLUS, respectively (p≤0.001). Nevertheless, the roughness values found did not present sufficient degradation to harbor bacteria. The surface roughness of all tested materials was increased by pH-cycling. The use of materials capable of resisting degradation in the oral environment is recommended, in order to conserve their integrity and of the surrounding tissues.

Is mouth-breathing related to alterations in facial soft tissues?

Objective: To compare the facial soft tissues of nasal breathers (NB) and mouthbreathers (MB) using cone-beam computed tomography (CBCT).Methods: This was a comparative study of four angular and eight linearcephalometric variables obtained from the facial soft tissues of 43 young menand women aged between 11 and 24 years. Subjects had tomographic examinationprior to the orthodontic treatment and were previously divided into two groupsby an otolaryngologist according to the respiratory pattern of nasal or mouthbreathing. The selection was made in accordance with the results of: clinicalexamination, rhinoscopy, and nasal endoscopy. The data obtained from thesoftware InVivo Dental 5.3 (Anatomage - San Jose, California) was evaluated bycomparing values measured between MB and NB groups. Results: There weresignificant differences between groups for variables, "nasolabial angle", inclinationof upper central incisor" and "convexity of the facial soft tissues". Conclusion:Adolescent and young adult mouth breathers present an open nasolabial angledue to the retroinclination of their upper incisors. In addition to greater convexityof the facial soft tissues.

Objetivo: Comparar os tecidos moles faciais de respiradores nasais (RN) e bucais(RB), utilizando imagens de tomografia computadorizada de feixe cônico (TCFC).Métodos: Foi realizado um estudo comparativo composto por quatro variáveiscefalométricas angulares e oito lineares, obtidas de tecidos moles faciais deindivíduos RN e RB, em uma amostra composta por 43 indivíduos jovens deambos os sexos, com idades entre 11 e 24 anos, submetidos ao exame tomográficoanteriormente ao tratamento ortodôntico. Os indivíduos foram previamentedivididos em dois grupos por um otorrinolaringologista, de acordo com o padrãorespiratório. O diagnóstico da respiração bucal foi feito em conformidade comos resultados de exames específicos: exame clínico, rinoscopia e endoscopia nasal.Os dados obtidos a partir do software InVivo 5.3 Dental (Anatomage - San Jose,Califórnia) foram avaliados através da comparação dos valores das mediçõesdas variáveis dos grupos RN e RB, além da comparação das diferenças entreesses valores. Resultados: Houve diferenças estatisticamente significativas entreos grupos com relação às variáveis, "ângulo nasolabial", "inclinação do incisivocentral superior" e "convexidade dos tegumentos faciais". Conclusão: Osrespiradores bucais adolescentes e adultos jovens apresentam ângulo nasolabialmais aberto, devido à maior inclinação lingual do longo eixo dos incisivossuperiores, além de maior convexidade dos tecidos moles faciais.