Longitudinal behavior of orthodontic extraction spaces: A retrospective dental cast analysis.

INTRODUCTION: This retrospective study aimed to qualitatively and quantitatively evaluate orthodontic extraction space behavior and size at the end of treatment and the short- and long-term stages in Class I, II, and III malocclusions. METHODS: The sample comprised records of 1283 orthodontic patients treated with extractions (cross-sectional group). From these patients, 1- and 5-year posttreatment records of 214 patients were additionally evaluated (longitudinal group). Orthodontic extraction sites of immediate (end of treatment), short-term (1-year posttreatment), and long-term (5-year posttreatment) stage dental casts were measured with a digital caliper. Extraction spaces were classified according to their qualitative behavior in the open, closed, reopened, and recently closed spaces. Space qualitative longitudinal behavior was compared among the malocclusion types with chi-square tests. Kolmogorov-Smirnov normality tests were performed to check the variable's distribution. All variables showed normal distribution, except the malocclusion group ages. Therefore, parametric tests were used for all comparisons between the malocclusion groups, except for age comparisons in each stage, which were compared with the Kruskal-Wallis tests. Thus, space size and its reduction were compared among the 3 stages, in general, and between the maxillary and mandibular arches, with analysis of variance followed by Tukey tests and t tests, respectively. RESULTS: Classes I, II, and III malocclusion patients presented similar ages at each stage. At the end of treatment, 71.4% and 65.1% of the quadrants were closed in the cross-sectional and longitudinal groups, respectively, and 43.6% and 38.2% of patients presented all quadrants closed at this same stage in both groups. The reopening and late closure tendencies were 2.9 and 2.3 times greater in the short term than in the long term. Reopening tendency in the short-term was greater in Class II than in Class I malocclusion. Of the quadrants closed at the end of treatment, 87% were stable in the long term. From the quadrants with residual spaces at the end of treatment, 28.4% persisted openly in the long term. Residual space size reduced significantly in the short and long term, primarily in the mandibular arch. CONCLUSIONS: The percentage of patients with residual spaces at the end of treatment was 56.4%. Space reopening and late closure occur mainly in the first year after treatment. There was long-term stability in 87% of the quadrants closed at the end of treatment. There was a significant reduction in orthodontic extraction space size in the short and long term, especially in the mandibular arch.

Long-term profile attractiveness in Class II Division 1 malocclusion patients treated with and without extractions.

INTRODUCTION: This study evaluated the influence of Class II treatment protocols in profile attractiveness. METHODS: Sixty-eight patients with initial full Class II Division 1 malocclusion, orthodontically treated an average of 15 years before, and matched by sex, age, time after treatment, orthodontic outcomes, and overjet, were compared. Three groups were formed, according to the treatment protocol: NE, nonextraction (n = 20; mean age 29.94 years, 15.62 years after treatment); 2E, 2-premolar extractions (n = 27; mean age 30.56 years, 15.09 years after treatment); and 4E, 4-premolar extractions (n = 21; mean age 32.29 years, 17.20 years after treatment). Cephalometric measurements and profile silhouettes were obtained from posttreatment and long-term posttreatment lateral cephalograms. With a 10-point numeric scale, 77 orthodontists and 77 laypeople rated profile attractiveness of each silhouette on a website. RESULTS: The raters' posttreatment and long-term posttreatment scores, respectively, were: NE 4.76 and 4.32; 2E 5.35 and 5.08; and 4E 4.53 and 4.33. CONCLUSIONS: The posttreatment profile attractiveness was significantly higher in the 2E than in the 4E group, and in the NE group it was similar to the others. The long-term profile attractiveness in the 2E group was significantly greater compared with the NE and 4E groups.

Tratamentos da classe II, com e sem extrações, e sua influência na estética facial em longo prazo

Altamente prevalente, a má-oclusão de classe II pode ser tratada com extrações de pré-molares. Porém, o ortodontista teme a repercussão negativa delas na face dos pacientes. Quando podemos extrair sem este medo? Quais fatores considerar: idade, severidade, apinhamento, padrão facial, projeção nasal, ângulo nasolabial? Avaliações 15 anos após tratamento mostram a influência estética em longo prazo dos diferentes protocolos de extração em pacientes classe II

Nowadays, the seek for aesthetics has been the subject of increased demanbd for orthodontiuc treatment in adults. The tooth agenesis has a great influence on the smile esthetics and consequently the harmony of the face, which is significantly affected by the absence of lateral incisors. Among the various treatment forms, the clinician can decide for space closure with replacement of the lateral incisor or canine space opening for later prosthetic implant rehabilitation. In the maxillary lateral incisors and made a literatura review about the treatment options, focusing on space opening associated with the planning and 3-D aesthetic management through the prothetic implant rehabilitation

Influence of premolar extractions on long-term adult facial aesthetics and apparent age.

OBJECTIVES: This study aimed to assess whether non-extraction, two-premolars and four-premolars extraction Class II treatment protocols are different regarding long-term facial aesthetics, age appearance, and soft-tissue measures. METHODS: Frontal and lateral photographs of 63 full Class II division 1 patients, treated at least 8 years before, were evaluated by 83 laypeople and 76 orthodontists, who assigned to each one's attractiveness scores from 1 to 10, and opined about their apparent ages. Patients were divided in three groups: XP0 (non-extraction, n = 20; 30.77 years, 15.63 years post-treatment), XP2 (two-premolars extractions, n = 25; 30.99 years, 15.68 years post-treatment), and XP4 (four-premolar extractions, n = 18; 32.80 years, 18.01 years post-treatment), that were matched by gender, post-treatment occlusal and soft-tissue outcomes, age, and post-treatment time. Soft-tissue measures were obtained with Dolphin Imaging 11.5 software. RESULTS: Two-way analysis of variance revealed that attractiveness and apparent age were not affected by treatment protocols, but laypeople were slightly more critical then orthodontists. Analysis of variance showed more vertical facial pattern in XP4 group. Pearson correlation test revealed no influence of soft-tissue measures on sample's attractiveness. CONCLUSIONS: Treatment of full Class II division 1 malocclusion with and without extractions did not influence facial attractiveness, age appearance, and overall soft-tissue measures in the long-term.

Soft-tissue changes in Class II malocclusion patients treated with extractions: a systematic review.

BACKGROUND: Concerns about the effects caused by premolar extractions on the soft-tissue profile have motivated many investigations in different malocclusions. OBJECTIVES: To evaluate the cephalometric facial soft-tissue changes after orthodontic treatment with premolar extractions of Class II division 1 malocclusion subjects. SEARCH METHODS: Electronic databases PubMed, Web of Science, Embase, and Scopus were searched. SELECTION CRITERIA: Abstracts that appeared to fulfil the initial criteria (premolar extraction; cephalometric soft-tissue analyses/changes) were selected. The full-text original articles were then retrieved. Their references were also hand-searched. DATA COLLECTION AND ANALYSIS: By consensus of two researchers, the articles that fulfilled the selection criteria and quantified facial soft-tissue changes were individually analysed. Some methodological flaws were identified and some articles were excluded. The studies were rated according to the type of study, sample description and homogeneity, malocclusion severity, consideration of confounding factors, validity of the method, and statistical analyses. RESULTS: Heterogeneous information about malocclusion severity before treatment was found in most articles. Statistically significant soft-tissue changes reported included nasolabial angle (NLA) increasing from 2.4 to 5.40degrees in 2-premolar extraction protocol and from 1 to 6.84degrees in 4-premolar extraction protocol. Retrusion of the upper and lower lips were also verified, with less retraction of the lower lip in 2-premolar extraction groups. CONCLUSIONS: When Class II division 1 malocclusion is treated with premolar extractions, the NLA increases and the lips are retracted. However, there is less retraction of the lower lip in the 2-maxillary premolar extraction protocol.

Maxillary incisors initial position and soft-tissue changes in Class II malocclusion extraction protocols / Posição inicial dos incisivos superiores e alterações no perfil facial nos protocolos de extração da má oclusão de Classe II

Introdução: Diferenças da atratividade encontradas entre os protocolos de tratamento Classe II em longo prazo e no pós-tratamento incitou estes estudos. O Elemento II demonstrou que os rostos bem equilibrados tem incisivos superiores posicionados em um relacionamento anteroposterior individualmente calculado com a testa. Deste modo, o Elemento II foi utilizado para investigar as características iniciais dos pacientes. Além disso, para avaliar as mudanças que os protocolos de extrações resultam nos tecidos moles, uma revisão sistemática foi realizada com busca nas bases de dados PubMed, Web of Science, Embase, Scopus e Cochrane. Resultados: O grupo CII teve posição AP dos incisivos superiores mais anteriores quando comparado ao grupo NO. Além disso, as posições AP dos incisivos nos subgrupos de extração foram à frente, quando comparado com o subgrupo NE. Alterações dos tecidos moles estatisticamente significantes foram ângulo nasolabial (NLA) que aumentou de 2,4º a 5,40º no protocolo de extração de 2 pré-molares e de 1º a 6,84º no protocolo de extração de 4 pré-molares. Retrusão dos lábios superior e inferior também foram verificadas, com menor retração do lábio inferior nos grupos de extração de dois pré-molares. Conclusões: Indivíduos com Classe II apresentaram os incisivos superiores significativamente mais protruídos que os indivíduos com oclusão normal. Na Classe II divisão 1, o subgrupo tratado com extrações apresentaram os incisivos significativamente mais protruídos em comparação com o subgrupo sem extrações. Quando Classe II divisão 1 é tratada com extrações de pré-molares, há aumento do NLA e os lábios são retraídos. No entanto, há menor retração do lábio inferior no protocolo de extração de 2 prémolares superiores.(AU)

Introduction: Differences in long-term and posttreatment attractiveness between Class II treatment protocols motivated these studies. Element II demonstrated that well-balanced faces have maxillary incisors positioned in an individually calculated anteroposterior relationship with the forehead. Thus, it was used to investigate the initial characteristics of the patients. Moreover, to evaluate the soft-tissue changes with extraction protocols, a systematic review was performed searching PubMed, Web of Science, Embase, Scopus and Cochrane electronic databases. Results: The CII group had forward incisors AP position when compared to the NO group. Also, the incisors AP positions in the extraction subgroups were forward when compared to the NE subgroup. Statistically significant soft-tissue changes reported included nasolabial angle (NLA) increasing from 2.4 to 5.40 degrees in the 2-premolar extraction protocol and from 1 to 6.84 degrees in the 4-premolar extraction protocol. Retrusion of the upper and lower lips were also verified, with less retraction of the lower lip in the 2-premolar extraction group. Conclusions: Class II subjects presented the maxillary incisors significantly more protruded than normal occlusion subjects. Class II division 1 extraction subgroups demonstrated significantly more protruded incisors as compared to the non-extraction subgroup. When Class II division 1 malocclusion is treated with premolar extractions, the NLA increases and the lips are retracted. However, there is less retraction of the lower lip in the 2- maxillary premolar extraction protocol.(AU)

Comparison between full face and hemifacial CBCT cephalograms in clinically symmetrical patients: a pilot study.

INTRODUCTION: One of the advantages of cone-beam computed tomography (CBCT) is the possibility of obtaining images of conventional lateral cephalograms derived from partial or complete reconstruction of facial images. OBJECTIVE: This study aimed at comparing full face, right and left hemifacial CBCT cephalograms of orthodontic patients without clinical facial asymmetry. METHODS: The sample comprised nine clinically symmetrical patients who had pretreatment full face CBCT. The CBCTs were reconstructed so as to obtain full face, right and left hemifacial cephalograms. Two observers, at two different times, obtained linear and angular measurements for the images using Dolphin 3D software. Dependent and independent t-tests were used to assess the reproducibility of measurements. Analysis of Variance and Kruskal-Wallis tests were used to compare the variables obtained in the CBCT derived cephalometric views. RESULTS: There was good reproducibility for CBCT scans and no statistically significant differences between measurements of full face, right and left hemifacial CBCT scans. CONCLUSIONS: Cephalometric measurements in full face, right and left hemifacial CBCT scans in clinically symmetrical patients are similar.

Comparison between full face and hemifacial CBCT cephalograms in clinically symmetrical patients: a pilot study

INTRODUCTION: One of the advantages of cone-beam computed tomography (CBCT) is the possibility of obtaining images of conventional lateral cephalograms derived from partial or complete reconstruction of facial images. OBJECTIVE: This study aimed at comparing full face, right and left hemifacial CBCT cephalograms of orthodontic patients without clinical facial asymmetry. METHODS: The sample comprised nine clinically symmetrical patients who had pretreament full face CBCT. The CBCTs were reconstructed so as to obtain full face, right and left hemifacial cephalograms. Two observers, at two different times, obtained linear and angular measurements for the images using Dolphin 3D software. Dependent and independent t-tests were used to assess the reproducibility of measurements. Analysis of Variance and Kruskal-Wallis tests were used to compare the variables obtained in the CBCT derived cephalometric views. RESULTS: There was good reproducibility for CBCT scans and no statistically significant differences between measurements of full face, right and left hemifacial CBCT scans. CONCLUSIONS: Cephalometric measurements in full face, right and left hemifacial CBCT scans in clinically symmetrical patients are similar. .

INTRODUÇÃO: uma das vantagens da tomografia computadorizada de feixe cônico (TCFC) é a possibilidade de obtenção da imagem da telerradiografia em norma lateral convencional, por reconstruir parcial ou totalmente a face em uma visão sagital. OBJETIVO: o presente estudo teve como objetivo comparar as imagens de cefalogramas obtidas da face total e das hemifaces direita e esquerda por meio de TCFC, em pacientes sem assimetria clinica. MÉTODOS: a amostra foi composta por nove pacientes, clinicamente simétricos, que tinham em seus prontuários TCFC de face total. Os exames tomográficos foram reformatados para a obtenção de cefalogramas de face total e hemifaces direita e esquerda. Dois observadores, em dois momentos diferentes, obtiveram medidas lineares e angulares dessas imagens, utilizando o software Dolphin 3D. Testes t dependentes e independentes foram utilizados para verificar a reprodutibilidade das medidas nas imagens. Análise de variância (ANOVA) e o teste de Kruskal-Wallis foram utilizados para comparar as variáveis obtidas nas análises cefalométricas. RESULTADOS: houve boa reprodutibilidade para as imagens de TCFC e não houve diferença estatisticamente significante entre as medidas cefalométricas obtidas de cefalogramas de face total, hemifaces direita e esquerda. CONCLUSÕES: medidas cefalométricas obtidas de cefalogramas de face total, hemifaces direita e esquerda em pacientes clinicamente simétricos são semelhantes. .

Influência em longo prazo dos protocolos de tratamento da Classe II na atratividade do perfil / Long term profile attractiveness in Class II division 1 malocclusion patients treated with and without extractions

A extração de pré-molares em Ortodontia tem sido questionada por eventuais riscos a estética do perfil. Este estudo se propôs a avaliar se há influência de três formas de tratamento da Classe II divisão 1 na atratividade do perfil ao final do tratamento e em longo prazo. Medidas cefalométricas foram obtidas das radiografias cefalométricas através do programa Dolphin Imaging 11.5 e comparações foram realizadas entre os grupos nos dois tempos. Os grupos foram divididos em tratamentos sem extração (XP0), com extração de dois pré-molares superiores (XP2) ou extração de quatro pré-molares (XP4). Foram avaliados 68 indivíduos com Classe II divisão 1 completa, tratados ortodonticamente há quinze anos, em média, compatíveis quanto ao sexo, idade ao final do tratamento e em longo prazo, tempo pós-tratamento, qualidade de finalização oclusal do tratamento (índice Objective Grading System) e sobressaliência (final e em longo prazo). O grupo XP0 foi composto de 20 indivíduos, com média de 29,94 (± 7,35) anos de idade e 15,62 (± 7,22) anos pós-tratamento. O grupo XP2 foi composto de 27 indivíduos com 30,56 (±5,74) anos de idade e 15,09 (± 4,79) anos pós-tratamento. O grupo XP4 foi composto por 21 indivíduos com 32,29 (± 5,70) anos de idade e 17,20 (± 5,76) anos pós-tratamento. As telerradiografias em norma lateral tomadas ao final dos tratamentos e nas consultas de reavaliação clínica deram origem a duas silhuetas de perfil de cada indivíduo. Leigos (77) e ortodontistas (77) avaliaram as silhuetas segundo seus critérios pessoais através de um site na internet, atribuindo notas de 1 a 10 à atratividade de cada uma. Leigos foram mais críticos em relação aos ortodontistas. A Análise de Covariância revelou que a idade ou o sexo dos avaliadores não interferiram sobre suas opiniões. A Análise de Variância revelou que o padrão facial foi suavemente mais vertical no grupo XP4 em relação ao XP2. Análises de Variância a dois critérios revelaram que a atratividade do perfil...

The assumption that extraction treatment can impair the facial profile has discouraged this treatment protocol in Class II malocclusion. This study aimed to assess whether there is influence of three different treatment protocols for Class II division 1 in the profile attractiveness by the end of treatment and in the long-term. Cephalometric measurements were obtained from the radiographs through the software Dolphin Imaging 11.5 and comparisons were made among the three groups for the two times. The groups were divided according to the treatment protocol: without extraction (XP0), with extraction of 2 maxillary premolars (XP2) or extraction of 4 premolars (XP4). Sixty-eight full Class II division 1 treated patients, matched by sex, end of treatment age, long-term posttreatment age, occlusal outcomes (index Objective Grading System) and overjet (final and in the long-term) were evaluated. The group XP0 consisted of 20 subjects, on average 29.94 (± 7.35) years old and 15.62 (± 7.22) years posttreatment. The group XP2 was composed of 27 individuals on average 30.56 (± 5.74) years old and 15.09 (± 4.79) years posttreatment. The XP4 group comprised 21 individuals on average 32.29 (± 5.70) years old and 17.20 (± 5.76) years post-treatment. The lateral radiographs taken by the end of treatments and in the long-term resulted in two profile black silhouettes of each patient. Through a website, laymen (77) and orthodontists (77) assigned scores from 1 to 10 to the each silhouettes attractiveness, according to their personal criteria. Laypeople were more critical than orthodontists. Analysis of covariance revealed that the age or sex of the evaluators did not interfere on their opinions. Analysis of variance revealed that the facial pattern was slightly more vertical in the group XP4 compared to XP2. Twoway Analysis of Variance revealed that the profile attractiveness in XP2 was significantly higher than in XP4 by the end of treatments and in XP0 were similar to both.