Skeletal alterations associated with the use of bonded rapid maxillary expansion appliance

Bonded maxillary expansion appliances have been suggested to control increases in the vertical dimension of the face after rapid maxillary expansion (RME). However, there is still no consensus in the literature about its real skeletal effects. The purpose of this prospective study was to evaluate, longitudinally, the vertical and sagittal cephalometric alterations after RME performed with bonded maxillary expansion appliance. The sample consisted of 26 children, with a mean age of 8.7 years (range: 6.9-10.9 years), with posterior skeletal crossbite and indication for RME. After maxillary expansion, the bonded appliance was used as a fixed retention for 3.4 months, being replaced by a removable retention subsequently. The cephalometric study was performed onto lateral radiographs, taken before treatment was started, and again 6.3 months after removing the bonded appliance. Intra-group comparison was made using paired t test. The results showed that there were no significant sagittal skeletal changes at the end of treatment. There was a small vertical skeletal increase in five of the eleven evaluated cephalometric measures. The maxilla displaced downward, but it did not modify the facial growth patterns or the direction of the mandible growth. Under the specific conditions of this research, it may be concluded that RME with acrylic bonded maxillary expansion appliance did promote signifciant vertical or sagittal cephalometric alterations. The vertical changes found with the use of the bonded appliance were small and probably transitory, similar to those occurred with the use of banded expansion appliances.Os aparelhos disjuntores com cobertura oclusal de acrílico têm sido sugeridos para controlar o aumento da dimensão vertical da face após a expansão rápida da maxila (ERM). Entretanto, ainda não há consenso na literatura sobre seu real efeito esquelético. O objetivo desse estudo prospectivo foi avaliar longitudinalmente as alterações esqueléticas verticais e sagitais após a ERM realizada com o aparelho disjuntor com cobertura oclusal. A amostra consistiu de 26 crianças, com idade média de 8,7 anos (variação: 6.9-10,9 anos), apresentando mordida cruzada posterior esquelética e indicação para ERM. Após a expansão maxilar, o aparelho foi utilizado como contenção fixa por 3,4 meses, sendo posteriormente substituído por uma contenção removível. O estudo cefalométrico foi realizado em telerradiografias laterais tomadas antes do início do tratamento e novamente 6,3 meses após a remoção do disjuntor. A comparação intragrupo foi feita utilizando-se o teste t pareado. Os resultados mostraram que não houve alterações esqueléticas sagitais significantes ao fim do tratamento. Houve um pequeno aumento em cinco das onze medidas cefalométricas verticais analisadas. A maxila se moveu inferiormente, porém não modificou o padrão de crescimento facial, a inclinação ou direção de crescimento mandibular. Considerando-se as condições específicas deste trabalho, pode-se concluir que a ERM realizada com o aparelho disjuntor com cobertura oclusal de acrílico não promoveu alterações esqueléticas verticais ou sagitais prejudiciais. As alterações verticais encontradas com o uso do aparelho colado foram pequenas e provavelmente transitórias, similar ao que ocorre com o uso dos aparelhos expansores bandados

Management of a complex dentoalveolar trauma: a case report

This paper describes the case of a 12-year-old male patient who presented a severe lateral luxation of the maxillary central incisors due to a bicycle fall. Treatment involved suture of the soft tissues lacerations, and repositioning and splinting of the injured teeth, followed by endodontic treatment and periodontal surgery. After a 2-year follow-up, clinical and radiographic evaluation revealed that the incisors presented satisfactory esthetic and functional demands.Este artigo apresenta o caso de um paciente de 12 anos de idade que apresentou uma luxação lateral severa dos incisivos centrais superiores decorrente de uma queda de bicicleta. O tratamento envolveu a sutura dos tecidos moles dilacerados e reposicionamento e fixação dos dentes traumatizados, seguidos por tratamento endodôntico e cirurgia periodontal. Após um acompanhamento de 2 anos, a avaliação clinica e radiográfica revelou que os incisivos apresentavam exigências estéticas e funcionais satisfatórias

Evaluation of sexual dimorphism and the relationship between craniofacial, dental arch and masseter muscle characteristics in mixed dentition

Purposeto evaluate sexual dimorphism and the relationship between craniofacial characteristics, dental arch morphology and masseter muscle thickness in children in the mixed dentition stage. Methodthe study sample comprised 32 children, aged 6-10 years (14♀/18♂) with normal occlusion. Craniofacial characteristics, dental morphology and masseter muscle thickness were evaluated by means of posteroanterior cephalometric radiographs, dental cast evaluation and ultrasound exam, respectively. The results were analyzed using Shapiro-Wilk test, Mann-Whitney/t-test and stepwise linear regression to assess the relation between face width and age, gender, body mass index, masseter thickness, distances between first molars and canines on dental casts (between cusps/cervical points), nasal, maxillary, mandibular and intermolar widths. Resultmasseter thickness showed no significant difference between the sides left/right. The comparison between genders showed significant difference only in face width, being larger in boys. The regression model showed that face width was positively related with body mass index, masseter thickness, mandibular first molar distances (cusps), mandibular canine distances (cervical points), and maxillary intermolar width; and negatively with maxillary (cusps) and mandibular molar distances (cervical points) and mandibular canine distances (cusps). That is, when the other studied variables were considered, the explanatory variable gender did not reach a significant value. Conclusionin the studied sample, the dimensions of the dental arches and masseter thickness did not differ between boys and girls; moreover, face width showed significant relationship with body mass index, masseter thickness, and dimensions of dental arches; but gender did not contribute significantly to face width variation.Objetivoavaliar o dimorfismo sexual e a relação entre as características morfológicas craniofaciais, dos arcos dentários e do músculo masseter na fase de dentição mista. Método32 crianças, com idade entre 6-10 anos (14♀/18♂) com oclusão normal, compuseram a amostra. Características morfológicas craniofaciais, dos arcos dentários e espessura do masseter foram avaliadas por meio de radiografia cefalométrica posteroanterior, modelos em gesso e ultrassonografia, respectivamente. Os resultados foram analisados utilizando testes Shapiro-Wilk, Mann-Whitney/teste “t” e regressão linear múltipla para avaliar a relação entre a largura da face e idade, gênero, índice de massa corporal, espessura do masseter, distâncias intermolares e intercaninos (entre cúspides e pontos cervicais) e larguras nasal, maxilar, mandibular e intermolar. Resultadoa espessura do masseter não diferiu significativamente entre os lados esquerdo e direito. A comparação entre os gêneros mostrou diferença significativa apenas na largura da face (maior em meninos). O modelo de regressão mostrou que a largura da face relacionou-se positivamente com o índice de massa corporal, espessura do masseter, distâncias intermolares (cúspides) e intercaninos (cervicais) inferiores e largura intermolar maxilar; e negativamente com a distância intermolares superiores (cúspides) e inferiores (cervicais) e intercaninos inferiores (cervicais). Ou seja, quando as demais variáveis foram adicionadas ao modelo, a variável explanatória gênero não alcançou valor significativo. Conclusãona amostra avaliada, a espessura do masseter e dimensões dos arcos dentários não diferiram entre gêneros; além disso, a largura da face mostrou relação significativa com o índice de massa corporal, espessura do masseter e dimensões dos arcos dentários, mas o gênero não contribuiu significativamente para sua variação.Universidade Estadual de Campinas Faculdade de Odontologia de Piracicaba Departamento de Odontologia InfantilUniversidade Federal do Rio Grande do Sul Departamento de FisiologiaUniversidade Estadual de Campinas Faculdade de Odontologia de Piracicaba Departamento de Odontologia infantilUniversidade Federal de São Paulo (UNIFESP) Departamento de Ciências BiológicasUNIFESP, Depto. de Ciências BiológicasSciEL

Masticatory muscle activity evaluation by electromyography in subjects with zygomatic implants

Zygomatic implants are an alternative treatment in the rehabilitation of atrophic maxilla to promote stability in the stomatognathic system. The aim of this study was to compare the electromyographic (EMG) activity of masseter and temporalis muscles in controls and in individuals with complete implant-supported dentures anchored in the zygomatic bone. Fifty-four volunteers of both genders (mean age 52.5 years) were selected and distributed into two groups: Individuals with zygomatic implant (ZIG; n=27) and fully dentate patients (CG; n=27). MyoSystem-BR1 was used to assess masseter and temporalis muscles EMG activity in different mandibular movements: protrusion, clenching, maximal voluntary contraction (MVC) with Parafilm M®, right and left laterality and chewing (peanuts and raisins). Data was processed, normalized (MVC) and analyzed using the SPSS 21.0. Student t-test (P ? 0.05) was used for group comparison. The results were statistically significant (P ? 0.05) for protrusion, clenching, right and left laterality and raisin chewing. For the mandibular posture conditions, the ZIG obtained higher EMG activity patterns when compared to CG. For the masticatory performance during chewing of peanuts and raisins, the ZIG showed higher EMG mean values when compared to CG. The zygomatic implant promoted an active response of the muscle fibers (hyperactivity) during both mandibular posture and chewing conditions, probably due to the absence of periodontal receptors, which play a significant role for preparing a bolus for swallowing

Effects of bonded rapid maxillary expansion appliance (brmea) in vertical and sagittal dimensions: a systematic review

Aim: The aim of this systematic review was to evaluate the existing literature about the effects of bonded rapid maxillary expansion appliance (BRMEA) on vertical and sagittal dimensions, and the possible advantages of its use. Methods: A comprehensive search was performed in Medline, Pubmed, and Web of Science full-text electronic journal databases to retrieve English-language articles referring to BRMA. The inclusion criteria to initially select abstracts were: human clinical trials involving the use of BRMEA, measurements made from lateral cephalometric radiographs, no surgical treatments or clinical reports. From a total of 24 abstracts dealing BRMEA, only 7 fulfilled all inclusion criteria. After reading the full text articles, 4 remained. Results: Critical review of these papers revealed a great heterogeneity in the methodologies regarding the evaluation periods, sample characteristics, linear and angular cephalometric measurements. The studies presented on this review showed that the vertical effects are only partially controlled with bonded devices. Conclusion: There is not sufficient evidence to support the use of BRMEA to control the undesirable effects of rapid maxillary expansion (RME). There is a need to study RME with BRMEA considering the patient s facial patterns in order to determine whether this appliance is actually efficient in controlling the undesirable effects of RME

Cephalometric evaluation of vertical and anteroposterior changes associated with the use of bonded rapid maxillary expansion appliance

INTRODUÇÃO: os aparelhos expansores maxilares com cobertura oclusal têm sido sugeridos para controlar o aumento na dimensão vertical da face após a expansão rápida da maxila, porém ainda não há um consenso na literatura sobre seus reais efeitos. OBJETIVO: o objetivo deste trabalho foi avaliar as alterações cefalométricas verticais e anteroposteriores associadas à expansão da maxila realizada com o aparelho expansor com cobertura oclusal. MÉTODOS: a amostra foi composta por 25 crianças, de ambos os gêneros, com idades entre 6 e 10 anos, portadoras de mordida cruzada posterior esquelética. Após a expansão maxilar, o próprio aparelho expansor foi utilizado como contenção fixa. Foram analisadas telerradiografias em norma lateral tomadas antes do início do tratamento e após a remoção do aparelho expansor. CONCLUSÃO: com base nos resultados, pôde-se concluir que o uso do aparelho expansor com cobertura oclusal não alterou significativamente as medidas cefalométricas verticais e anteroposteriores das crianças.INTRODUCTION: Bonded rapid maxillary expansion appliances have been suggested to control increases in the vertical dimension of the face after rapid maxillary expansion but there is still no consensus in the literature concerning its actual effectiveness. OBJECTIVE: The purpose of this study was to evaluate the vertical and anteroposterior cephalometric changes associated with maxillary expansion performed using bonded rapid maxillary expansion appliances. METHODS: The sample consisted of 25 children of both genders, aged between 6 and 10 years old, with skeletal posterior crossbite. After maxillary expansion, the expansion appliance itself was used for fixed retention. Were analyzed lateral teleradiographs taken prior to treatment onset and after removal of the expansion appliance. CONCLUSION: Based on the results, it can be concluded that the use of bonded rapid maxillary expansion appliance did not significantly alter the children's vertical and anteroposterior cephalometric measurements

Electromyographic evaluation in children having rapid maxillary expansion

Introduction: The aim of this study was to analyze the electromyographic activity of the masseter and temporalis muscles of children having rapid maxillary expansion (RME) with a bonded rapid maxillary expansion appliance. Methods: The sample consisted of 27 children (mean age, 8.6 years) with posterior crossbite who required RME treatment. Electromyographic activity of the masseter and temporalis muscles was analyzed before treatment and after the appliance was removed. The mean interval between the 2 analyses was 5 months. Muscular activity was electromyographically analyzed in rest position, and with maximum voluntary dental clenching and chewing. Differences in the 2 measurements were evaluated by using paired t tests. Results and Conclusions: Electromyographic analysis showed that activity of the masseter and temporalis muscles increased significantly after the expansion appliance was removed during rest, dental clenching, and habitual chewing. (Am J Orthod Dentofacial Orthop 2009;136:355-60

Effects of bonded rapid maxillary expansion appliance (BRMEA) in vertical and sagittal dimensions: a systematic review

e aim of this systematic review was to evaluate the existing literature about the effects of bonded rapid maxillary expansion appliance (BRMEA) on vertical and sagittal dimensions, and the possible advantages of its use. Methods: A comprehensive search was performed in Medline, Pubmed, and Web of Science full-text electronic journal databases to retrieve English-language articles referring to BRMA. The inclusion criteria to initially select abstracts were: human clinical trials involving the use of BRMEA, measurements made from lateral cephalometric radiographs, no surgical treatments or clinical reports. From a total of 24 abstracts dealing BRMEA, only 7 fulfilled all inclusion criteria. After reading the full text articles, 4 remained. Results: Critical review of these papers revealed a great heterogeneity in the methodologies regarding the evaluation periods, sample characteristics, linear and angular cephalometric measurements. The studies presented on this review showed that the vertical effects are only partially controlled with bonded devices. Conclusion: There is not sufficient evidence to support the use of BRMEA to control the undesirable effects of rapid maxillary expansion (RME). There is a need to study RME with BRMEA considering the patients facial patterns in order to determine whether this appliance is actually efficient in controlling the undesirable effects of RME

Characteristics of masticatory muscles in children with unilateral posterior crossbite

The aim of this study was to detect possible differences in the EMG (electromiography) activity, chewing rate (CR), cycle duration (CD) and preferred chewing side (PCS) between children with and without unilateral posterior crossbite. Thirty-seven children aged from 7 to 10 years were selected from the clinic of the Department of Pediatric Dentistry, Piracicaba Dental School, Brazil, and divided into two groups: unilateral posterior crossbite (UPCB group, n = 17), and normal occlusion (NOccl group, n = 20). The PCS was determined using a visual spot-checking method. The EMG activity was recorded during mastication, and two chewing sequences of 20 s were evaluated to establish each subject’s CR (cycles/sec) and CD. UPCB and NOccl groups did not have a PCS. The EMG activity and the cycle characteristics did not differ between the groups. The correlations between CD, CR and EMG activity were statistically significant for the masseter and anterior temporalis muscles only in the NOccl group, in which there was also a significant correlation between the EMG activity of masseter and anterior temporalis. In conclusion, these findings suggest that although children with and without UPCB presented a bilateral masticatory pattern with similar CR and CD, balanced EMG activity of masseter and anterior temporalis muscles was observed only in the NOccl group. These results indicate that in children, UPCB can alter the coordination of masticatory muscles during mastication