Duración de la erupción dental prefuncional temporal y permanente en la población de Villa Clara / Duration of temporary and permanent prefunctional tooth eruption in Villa Clara population

Introducción: En Cuba ha sido poco estudiado el tiempo que demora el diente, desde que aflora a la cavidad bucal hasta que alcanza el plano oclusal. Objetivo: Determinar la duración de la erupción clínica prefuncional temporal y permanente en la población de Villa Clara. Métodos: Se realizó un estudio epidemiológico descriptivo entre los años 2014 a 2018. Mediante un muestreo polietápico aleatorio simple se obtuvo una muestra de 2 584 niños y adolescentes (520 entre tres meses y cuatro años para la dentición temporal, y 2 064 entre cuatro y 14 años para la permanente), nacidos en la provincia, sin alteraciones del crecimiento general y craneofacial; se observó el brote; se calcularon por medio de la regresión de probit, las edades medias para los dientes brotados sin contacto oclusal y las que habían alcanzado la oclusión. La duración de la erupción clínica prefuncional fue calculada restando las medianas de ambas variables. Resultados: En los dientes temporales demoró más la erupción clínica prefuncional en los 1ros molares (superiores, 0,63; inferiores, 0,62); en los permanentes, en los incisivos centrales inferiores de hombres y mujeres, 1 y 1,07, respectivamente. Conclusiones: La erupción clínica prefuncional para los dientes permanentes osciló entre cuatro meses y un año; para los temporales, entre cuatro y siete meses con diferencias dentarias. Se elaboró una tabla de duración de la erupción clínica prefuncional de los dientes temporales y permanentes ajustada a la población villaclareña.

Introduction: the time the tooth takes to emerge from the oral cavity until it reaches the occlusal plane has been little studied in Cuba. Objective: to determine the duration of temporary and permanent prefunctional clinical tooth eruption in Villa Clara population. Methods: a descriptive and epidemiological study was carried out from 2014 to 2018. A sample of 2,584 children and adolescents who were born in the province without alterations in general and craniofacial growth was obtained through simple random multistage sampling (520 between three months and four years for temporary dentition and 2,064 between four and 14 years for permanent one); the outbreak was observed; the mean ages for teeth eruption without occlusal contact and those that had reached occlusion were calculated by means of probit regression. The duration of the prefunctional clinical eruption was calculated by subtracting the medians of both variables. Results: prefunctional clinical eruption took longer in temporary (upper, 0.63 and lower, 0.62) 1st molars, as well as in permanent lower central incisors of men and women (1 and 1.07, respectively). Conclusions: prefunctional clinical eruption for permanent teeth ranged from four months to one year and for temporary ones between four and seven months presenting dental differences. A table of the duration of the prefunctional clinical eruption of temporary and permanent teeth was created according to Villa Clara population.

Prevalence and Associated Factors of Dental Trauma in Six-Year-Old School-Children

ABSTRACT Objective: To estimate the prevalence and associated factors of dental trauma in 6-year-old school children in the city of Palhoça, Brazil. Material and Methods: Cross-sectional study nested in a cohort study. It involved a representative sample of school children born in 2009, residing in the municipality and regularly enrolled in public and private schools (n = 1,102). Clinical data were obtained through oral exams. To evaluate the incisal overjet, the distance in millimeters was measured horizontally from the labial surface of the lower central incisor to the labial surface of the upper incisor. Bivariate analyses were performed using the Chi-square test, with a p-value <0.05 considered statistically significant. Multivariate analyses using Poisson Regression were performed to identify independent associations between the prevalence and the independent variables studied. Results: Prevalence of dental trauma was 4.2% (95% CI 3.0-5.4). Dental trauma was statistically associated with studying in a private school (PR = 1.03; 95% CI 1.01-1.06) (p=0.016) and with inadequate lip coverage (PR = 1.08; 95% CI 1.01-1.14) (p=0.016). Conclusion: The prevalence of 4.2% of dental trauma in six-year-old children, associated with inadequate and greater lip coverage in children from private schools should be taken into account, since most teeth at this stage are newly erupted.

Patterns of dental anomalies in patients with nonsyndromic oral cleft

Aim: To characterize the patterns of dental anomalies (DA) in the mixed and permanent dentitions of patients with nonsyndromic oral cleft (NSOC). Methods: This cross-sectional, observational, case-control study included 173 patients, 61 with mixed dentition (NSOC=29 and control=32) and 112 with permanent dentition (NSOC=57 and control=55). All subjected were submitted to clinical and radiographic examination. Dental anomalies of eruption, number, size and shape outside the cleft area were considered. Results: Although there was no statistical significance among patients with mixed dentition, dental agenesis was the anomaly more common in this group. In patients with permanent dentition, a higher prevalence of DA in NSOC group compared to control group was observed (p=0.02). Gyroversion and dental agenesis were the DA more frequently observed in the permanent dentition and the second premolar was the tooth more affected (p=0.003). Mandible and the left side were more involved, and dental agenesis was more frequently found in patients with unilateral cleft lip with or without cleft palate (NSCL±P). Conclusion: Our findings show a higher frequency of DA in NSOCs than in the control group in patients with permanent dentition, mainly due to a higher occurrence of agenesis of second premolars in patients with unilateral NSCL±P

MORDIDA CRUZADA ANTERIOR: POSSIBILIDADES DE TRATAMENTO NA DENTIÇÃO DECÍDUA E MISTA / ANTERIOR CROSSBITE: TREATMENT POSSIBILITIES IN DECIDUOUS AND MIXED DENTITION

A mordida cruzada anterior (MCA) refere-se a uma maloclusão cuja relação vestíbulo-lingual entre incisivos superiores e inferiores é anormal, com sobressaliência negativa. Esta alteração pode promover comprometimento da estética dento-facial e das funções do sistema estomatognático. A MCA pode ser classificada em 3 tipos: Dentária (MCAD), Funcional (MCAF) e esquelética (MCAE). O objetivo deste trabalho foi, por meio de uma revisão de literatura, apresentar as diferentes possibilidades de tratamento da MCA nas dentições decídua e mista. O tratamento da MCAD tem como objetivo a correção das inclinações anormais dos elementos envolvidos. O tratamento da MCAF pode ser realizado por movimentação dentária pelas pistas diretas preconizadas por Planas. A abordagem da MCAE tem como objetivo a correção esquelética e dependerá do grau de displasia óssea e da idade de início do tratamento. Concluiu- se que a MCA deve ser tratada tão logo seja diagnosticada, por meio das diferentes formas de tratamento apresentadas, de acordo com a etiologia e apresentação clínica. Todos os tratamentos propostos apresentam altos índices de sucesso se corretamente planejados e executados.

Anterior crossbite (MCA) refers to a malocclusion whose vestibular- lingual relationship between upper and lower incisors is abnormal, with a negative overjet. This alteration may promote impairment of dento-facial aesthetics and functions of the stomatognathic system. The MCA can be classified into 3 types: Dental (MCAD), Functional (MCAF) and skeletal (MCAE). The objective of this literature review was to present the different possibilities of MCA treatment in the deciduous and mixed dentitions. The treatment of MCAD aims at correcting the abnormal inclinations of the involved elements. The treatment of MCAF can be performed with composite as an inclined plane tracks recommended by Planas. The MCAE approach aims at skeletal correction and depends on the degree of bone dysplasia and the age at which treatment begins. According this study, we can conclude that the MCA should be treated as soon as diagnosed, by the different forms of treatment presented, according to etiology and clinical presentation. All the proposed treatments may have high success rates if correctly planned and executed.

Alternative of timely treatment of unilateral posterior cross-bite in primary and mixed early dentition. Case series / Tratamiento de la mordida cruzada posterior unilateral en dentición primaria y mixta temprana: Serie de casos

Introduction Unilateral posterior cross bites (UPCB) are one of the most frequent types of malocclusions found in both primary and early mixed dentitions. Due to its multifactorial origin, its treatment is focused not only on the correction of malocclusion, but also on long-term functional and occlusal stability that reduces alterations in the growth and development of the stomatognathic system at an early age. The objective of this series of cases is to present two alternatives of timely treatment for this malocclusion. Description of the cases The first case is an 8-year-old patient with left UPCB who receives controlled palatal expansion treatment with a Hyrax screw with acrylic splint, in which favorable results are obtained in a short time and with long-term stability. The second case, a 4-year-old patient with a right UPCB is presented with Planas' direct tracks, achieving a desired mandibular postural change. Discussion The treatment alternatives presented, several authors have reported a series of benefits obtained from the type of intervention that not only achieve the correction of malocclusion, but also achieve the improvement of structures that make up the craniofacial complex, within which highlights the desired long-term stability. These benefits are obtained through the selected treatment alternative, according to the diagnosis and clinical characteristics presented in each patient and justifies the decision to perform an early intervention especially in this type of malocclusion. Conclusion The early treatment of the unilateral posterior crossbite should be selected according to the type of dentition and the patient's need, which favors the proper growth and development of the stomatognathic system.

Introducción: Las mordidas cruzadas posteriores unilaterales (MCPU) constituyen uno de los tipos de maloclusiones más frecuentes encontrados tanto en dentición primaria como en dentición mixta temprana. Debido a su origen multifactorial su tratamiento se encuentra enfocado no solo en la corrección de la maloclusión, sino en obtener una estabilidad oclusal y funcional a largo plazo que disminuya las alteraciones en el crecimiento y desarrollo del sistema estomatognático en edades tempranas. El objetivo de esta serie de casos es presentar dos alternativas de tratamiento oportuno para esta maloclusión. Descripción de los casos: El primer caso es un paciente de 8 años de edad con MCPU izquierda quien recibe tratamiento de expansión palatina controlada con un tornillo tipo Hyrax con férula acrílica, en el cual se obtienen resultados favorables en corto tiempo y con estabilidad a largo plazo. El segundo caso es una paciente de 4 años de edad con MCPU derecha a la cual se le realizan Pistas Directas Planas logrando un cambio postural mandibular deseado. Discusión: En las alternativas de tratamiento presentadas, varios autores han reportado una serie de beneficios obtenidos a partir del tipo de intervención que no solo logran la corrección de la maloclusión, sino que a su vez alcanzan la mejoría de estructuras que componen el complejo craneofacial, dentro de los cuales se destaca la estabilidad a largo plazo deseada. Estos beneficios se obtienen a través de la alternativa de tratamiento seleccionada, según el diagnóstico y las características clínicas presentadas en cada paciente y justifica la decisión de realizar una intervención temprana especialmente en este tipo de maloclusión. Conclusión: El tratamiento temprano de la mordida cruzada posterior unilateral debe ser seleccionado según el tipo de dentición y necesidad del paciente, lo que favorece el adecuado crecimiento y desarrollo del sistema estomatognático.

A Newly Proposed Regression Equation for Mixed Dentition Analysis Using the Sum of the Width of Permanent Mandibular Central Incisors and Permanent Mandibular First Molars as a Predictor of Width of Unerupted Canine and Premolars

Objective: To determine linear regression equation to predict the mesiodistal widths of the permanent canines and premolars based on the sum of the widths of the two permanent mandibular first molars and two mandibular central incisors. Material and Methods: The sample consisted of 800 (400 males and 400 females) permanent dentition casts of Chhattisgarh population. Mesiodistal crown widths of teeth were measured with digital caliper. The correlation and linear regression equations between the calculated four teeth (two permanent mandibular first molars and two central incisors) and the canine-premolars segments of both the arches were developed. Results: No significant differences were found in right and left side of the arch. Sexual dimorphism was significant in teeth sizes with higher mesiodistal dimension in males. A good correlation values varying from 0.51 to 0.67 was found. New standardized regression equations were formulated for the prediction of the mesiodistal widths of unerupted canines and premolars for Chhattisgarh population. Conclusion: Calculating mesiodistal widths of unerupted canine and premolars with help of two permanent mandibular molars and two mandibular central incisors, which erupt early in the oral cavity, can be an alternative and best predictor for the mixed dentition analysis.

Comparison of Two Different Non-Radiographic Mixed Dentition Analysis

Objective: To evaluate the applicability of two different non-radiographic mixed dentition analysis in school going children of Aligarh district, India. Material and Methods: Mesiodistal dimension was measured on the dental casts of 120 school going children with electronic digital vernier caliper. The following inclusion criteria were adopted: presence of all fully erupted permanent teeth; no congenital craniofacial anomalies; no previous history of orthodontic treatment; and presence of intact dentition with no proximal caries, restoration, or age related attrition. Predicted values of canines and premolars were obtained from Moyer's at 75th percentile and Tanaka and Johnston mixed dentition analysis. Descriptive statistics were used to calculate the mean and standard deviation. Paired observations were compared by t­test. The level of significance was at p<0.001. Results: The mean difference between the predicted and the actual value of canines and premolars using Moyer's probability table at 75th percentile and Tanaka and Johnston regression equation were statistically significant. No significant differences were found between Moyer's analysis 75th percentile and Tanaka and Johnston mixed dentition analysis in both arch and sexes. Conclusion: These two non-radiographic mixed dentition analysis overestimated the mesiodistal width of canines and premolars.

A New Regression Equation Proposed For Mixed Dentition Analysis in Chhattisgarh, Central India Population

Objective: To develop and propose a new regression for mixed dentition analysis in Chhattisgarh, Central India population. Material and Methods: The permanent dentition dental casts of 800 (400 males and 400 females) Chhattisgarh subjects were selected. Digital caliper was used to measure the mesiodistal crown widths of teeth. The linear regression equations and correlation between four mandibular incisors and the canine-premolars segments of maxillary and mandibular arches were developed (modified Tanaka-Johnston equation) and proposed for Chhattisgarh population. Results: New standardized regression equations were formulated to predict the mesiodistal widths of unerupted canines and premolars especially for Chhattisgarh, Central India population. The equation in males for maxillary arch was Y = 11.90 + 0.39 (X) and for mandibular arch was Y = 12.23 + 0.36 (X). Similarly, the equation in females for maxillary arch was Y = 14.40 + 0.26 (X) and for mandibular arch was Y= 10.26 + 0.43 (X). A significant sexual dimorphism in teeth sizes was seen with higher mesio distal dimension in males in Chhattisgarh population. Conclusion: Sum of the mesiodistal diameter of permanent mandibular incisors can be used reliably to predict/estimate the sum of mesiodistal diameters of unerupted canines and premolars with the new regression equations.

Image quality assessment of pre-processed and post-processed digital panoramic radiographs in paediatric patients with mixed dentition

PURPOSE: To determine the impact of an image processing technique on diagnostic accuracy of digital panoramic radiographs for the assessment of anatomical structures in paediatric patients with mixed dentition. MATERIALS AND METHODS: The study consisted of 50 digital panoramic radiographs of children aged from 6 to 12 years, which were later on processed using a dedicated image processing method. A modified clinical image quality evaluation chart was used to evaluate the diagnostic accuracy of anatomical structures in maxillary and mandibular anterior and maxillary premolar region of processed images. RESULTS: A statistically significant difference was observed between pre and post-processed evaluation of anatomical structures (P 0.05). The Inter-observer and intra-observer reliability of both pre and post processed images were excellent (>0.82) for anterior region and good (>0.63) for premolar region. CONCLUSION: The application of image processing technique in digital panoramic radiography can be considered a reliable method for improving the quality of anatomical structures in paediatric patients with mixed dentition.

Prevalence and etiology of dental trauma in schoolchildren aged 6 to 12 years

Aim: To investigate the prevalence and etiological factors of dental trauma in school-age children aged 6 to 12 years. Methods: A study was developed in children and adolescents between the ages of 6 and 12 of both genders enrolled in 3 municipal public schools. An oral examination of the permanent or deciduous incisors was performed, if they were still present in the oral cavity, to evaluate the presence of dental trauma, need for treatment and sequels, and the method of examination and classification of dental trauma of O'Brien. Results: The prevalence of dental trauma was 4.03% (n=29). The most verified traumas were enamel crack / enamel fracture and enamel / dentin fracture without pulp exposure. It was observed that the most affected teeth were the permanent upper central incisors and the age at which trauma was most observed was 11 years, the main etiological factor was fall from a height, in 65.3% of schoolchildren (n=19). Conclusion: The prevalence of dental trauma was 4.03%, with no statistically significant difference between genders. The permanent right upper central incisor was the most affected, occurring predominantly at home and at school. The dissemination of information about dental trauma and emergency protocols to parents and teachers need to be encouraged

Mordida cruzada posterior em dentição mista / Posterior cross bite in mixed dentition

A mordida cruzada posterior é definida como a relação anormal vestíbulo-lingual de um ou mais dentes da maxila, com um ou mais dentes da mandíbula, quando os arcos dentários estão em relação cêntrica, podendo ser uni ou bilateral. Dentre as más oclusões de maior frequência destacam-se as mordidas cruzadas. O presente estudo tem como objetivo, com base numa revisão da literatura, elucidar conceitos sobre: a mordida cruzada posterior; prevalência, etiologia; classificação; diagnóstico e tratamento; e aparelhos utilizados para a correção. O presente estudo mostrou que a maioria dos autores afirma que o aparelho Quadrihélice é muito eficaz e possui baixo custo, principalmente quando usado precocemente. Já outros autores consideram que, na mordida cruzada posterior tratada com expansão rápida da maxila, o disjuntor Haas e o Hyrax foram considerados como melhor tratamento devido à boa estabilidade.

Posterior cross bite is defined as the abnormal relationship lingual-vestibule of one or more teeth of the maxilla, with one or more teeth of the mandible when the dental arches are in centric relation, and it may be unilateral or bilateral. Among the most malocclusions often there is the cross bite. The aim of this study, based on a literature review, is to clarify concepts about: posterior cross bite; prevalence, etiology; classification; diagnosis and treatment; and apparatus for correction. The present study showed that the majority of authors states that the Quad-helix appliance is very effective because it is more affordable, especially if the malocclusion is treated early. Already, other authors consider that the posterior cross bite treated with rapid maxillary expansion with Haas and Hyrax were considered as best treatment because of good stability.

Evaluation of Three Different Regression Equations Based Mixed Dentition Analysis in Children of Moradabad City, India

Objective: To assess the accuracy and applicability of three regression equations based mixed dentition analysis in children of Moradabad city, India. Material and Methods: Actual mesiodistal width of maxillary and madibular incisors, canines and premolars of 100 children (50 male and 50 female) aged 11-14 years were measured on dental cast with electronic digital vernier caliper. The analysis of Tanaka- Johnston, Ling-Wong and Jaroontham-Godfrey regression equations were tested on the dental casts. All analyses were performed on SPSS software. Data were summarized as Mean ± standard deviation (SD) paired observations were compared by paired t-test (two-tailed test) while independent groups were compared by independent Student's t-test. The level of significance was at P < 0.001. Results: The analysis of Tanaka-Johnston, Ling-Wong, Jaroontham-Godfrey regression equations tended to overestimate the mesiodistal width of the canines and premolars with the actual measured values. Conclusion: All the three regression equations based mixed dentition overestimated the mesiodistal width of canines and premolars in Moradabad population.

Força de mordida em crianças com mordida cruzada posterior / Bite force in children with posterior crossbite

RESUMO Introdução A força de mordida é influenciada pela condição oclusal. Em crianças com mordida cruzada posterior, os resultados são controversos. Objetivo Investigar a influência da mordida cruzada posterior na força isométrica máxima de mordida, em crianças na fase de dentição mista. Métodos Participaram deste estudo transversal 32 crianças, sendo 21 do grupo mordida cruzada posterior (10 meninas e 11 meninos, média de idade 9,2 anos) e 11 do grupo controle, sem alterações oclusais (seis meninas, cinco meninos, média de idade 9,3 anos). As crianças foram avaliadas por um ortodontista, para diagnóstico oclusal e caracterização dos grupos, pela equipe de otorrinolaringologia, para avaliação do quadro respiratório, e por uma fonoaudióloga. O dinamômetro foi posicionado na região dos molares e as crianças foram instruídas a mordê-lo o mais forte possível, por três vezes, alternadamente. Para análise dos dados foi utilizado o teste t de Student para amostras independentes e dependentes. O nível de significância estabelecido foi de 5%. Resultados Na comparação entre os grupos mordida cruzada e controle não foi encontrada diferença significativa e no grupo mordida cruzada, não houve diferença entre o lado cruzado e o não cruzado. Conclusão A presença de mordida cruzada posterior não esteve relacionada à força de mordida em crianças na fase de dentição mista.

ABSTRACT Introduction The bite force is influenced by the occlusal condition. In children with posterior crossbite the results are controversial. Purpose To investigate the influence of posterior crossbite in maximal isometric bite force (MIBF) in children with mixed dentition. Methods In this cross-sectional study, 32 children participated, 21 of them belonging to the posterior cross-bite group (10 girls and 11 boys, mean age 9.2 years) and 11 to the control group (6 girls, 5 boys, mean age 9.3 years). The children were evaluated by an orthodontist for occlusal diagnosis and characterization of the groups, by otorhinolaryngologists for evaluation of respiratory symptoms and by a speech therapist to identify the clinical and MIBF myofunctional orofacial condition. The dynamometer was placed in the molar region and the children were instructed to bite it as hard as possible three times alternately. For data analysis, Student’s t-test for independent samples was used. The level of significance was set at 5%. Results While comparing the groups crossbite vs. control, there was no significantly difference; also, among only children belonging to the crossbite group, there was no difference between the sides (crossed bite vs. Noncrossed one). Conclusion The presence of posterior crossbite did not influence the maximal isometric bite force in children with mixed dentition.

Malocclusion in schoolhildren aged 7-12 years old in Minas Gerais, Brazil / Má Oclusão em escolares de 7 a 12 anos de idade em Minas Gerais, Brasil

ABSTRACT Objective The aim of the study was to determine prevalence of malocclusion and the inter- and intra-arch relations in schoolchildren of 7-12 years of Vazante, Minas Gerais, Brazil. Methods In the inter-arch relations the sagittal, vertical and transverse aspects were evaluated, and in the intra-arch relations, diastemas, crowding and tooth losses were determined in 670 children. The maloclussion was classified as Class I , II and III according to Angle, based on the position of the first molars. For this study, the sample was divided into two age groups: children from 7 to 9 years and children from 10 to 12 years old. Results A similar percentage of individuals with Class I and II was found in the two age groups evaluated. A higher percentage of Class III individuals was observed in the age group from 10 to 12 years. The presence of cross bite, anterior open bite, diastemas, crowding and early primary tooth loss was prevalent in the age groups of 7 and 9 years. Deep bite, posterior cross bite and early loss of permanent teeth prevailed in the age from 10 to 12 years. Conclusion It could be concluded that there was a high rate of malocclusion in children and the sagittal relation was maintained in the two periods evaluated. A larger number of manifestations of anterior open bite were observed in the age group of 7 to 9 years, and overbite in the Group from 10 to 12 years. In the transverse relation there was an increase in cross bite from the first to second transitory period.

RESUMO Objetivo Determinar a prevalência de má oclusão e as relações inter e intra-arco em escolares de 7 a 12 anos de Vazante, Minas Gerais, Brasil. Métodos Nas relações inter-arco os aspectos no plano sagital, verticais e transversais foram avaliados e, no intra-arco, as relações de diastemas, apinhamento e perdas dentárias foram determinadas em 670 escolares. A má oclusão foi classificada em classe I, II e III de acordo com Angle, baseada na posição dos primeiros molares. Para este estudo, a amostra foi dividida em dois grupos etários: crianças 7-9 anos e crianças dos 10 aos 12 anos de idade. Resultados Uma percentagem semelhante de indivíduos com má oclusão de Classe I e II foi encontrado nos dois grupos etários avaliados. A maior percentagem de indivíduos com má oclusão de Classe III foi observada na faixa etária dos 10 aos 12 anos. A presença de mordida cruzada, mordida aberta anterior, diastemas, apinhamento e perda dentária precoce primária foi prevalente nas faixas etárias de 7 e 9 anos. Sobremordida profunda, mordida cruzada posterior e perda precoce dos dentes permanentes prevaleceram na faixa etária de 10-12 anos. Conclusão Pode-se concluir que houve uma alta taxa de má oclusão em crianças e a relação sagital foi mantido nos dois períodos avaliados. Foi observado um maior número de mordida aberta anterior na faixa etária de 7 a 9 anos, e sobremordida profunda no grupo dos 10 aos 12 anos. Na relação transversal, houve um aumento da mordida cruzada do primeiro para o segundo período de transição.

Força de mordida em respiradores bucais / The magnitude of the bite force in mouth breathers

RESUMO Objetivo Investigar a influência da respiração bucal na força de mordida máxima de dentes molares em crianças. Métodos Cento e cinco crianças foram divididas em dois grupos: grupo controle (GC), sem queixas respiratórias e com padrão clínico de vedamento labial e grupo de respiradores bucais (GRB), com queixas respiratórias e diagnóstico otorrinolaringológico de obstrução nasal. Todos os participantes realizaram a avaliação da força de mordida isométrica máxima (FMIM), de ambos os lados da arcada dentária, por meio de um gnatodinamômetro posicionado na região dos primeiros molares. Os testes estatísticos t de Student pareado e não pareado foram usados nas comparações da FMIM entre os lados, de cada grupo, e entre os grupos (GC e GRB). O grau de obstrução foi correlacionado à FMIM (GRB), por meio do teste de correlação de Spearman. Foram considerados significativos resultados com p≤0,05. Resultados Não houve diferença nos valores de FMIM entre os lados direito e esquerdo da arcada dentária. Quando comparados os valores de FMIM dos participantes do GC e do GRB não foi observada diferença, de um modo geral. Entretanto, quando correlacionada a FMIM com a idade dos participantes da pesquisa, notou-se que no GC houve aumento no valor da FMIM, de acordo com a idade. Conclusão A obstrução nasal não influenciou na força de mordida isométrica máxima em crianças de 3 a 12 anos de idade. Não houve correlação entre o grau de obstrução e a força de mordida. No GC a força de mordida foi maior em crianças mais velhas, porém, essa correlação com a idade não foi observada no GRB.

ABSTRACT Purpose To investigate the influence of mouth breathing on the maximum molar bite force in children. Methods One hundred and five children were divided into two groups: the control group (CG) without respiratory symptoms and the clinical pattern of a competent lip seal, and the mouth breathers (MB) who had respiratory complaints and an otorhinolaryngological diagnosis of nasal obstruction. All participants were assessed for their maximum isometric bite force (MIBF), on both sides of the dental arch, with a gnathodynamometer positioned in the region of the first molars. Paired and unpaired Student's t-tests were used in the comparisons of the MIBF of both sides from each group and between each group (CG and MB). The degree of obstruction was correlated with MIBF (MB), using the Spearman correlation test. Results with p≤0.05 were considered significant. Results There were no significant differences in the MIBF values between the right and left sides of the dental arch. In a comparison of the MIBF values of the CG and MB participants, no difference between the groups were found in general. However, when the age of the survey participants was correlated against MIBF, an increase in MIBF value according to age was evident for the CG participants. Conclusion Nasal obstruction did not influence maximum isometric bite force in children between three and 12 years old. There was no correlation between the degree of obstruction and the bite force. The CG bite force was higher for older children, however, this correlation was not observed in MB.

Breastfeeding, bottle feeding and risk of malocclusion in mixed and permanent dentitions: a systematic review

Abstract The aim of the present study was to search for scientific evidence concerning the association between breastfeeding and bottle feeding and risk of malocclusion in mixed and permanent dentitions. An electronic search was performed in eight databases up to February 2015. Additionally, a gray literature search and hand searches of the reference lists of the selected studies were also carried out. There were no restrictions on language or on year of publication. The methodology of the included articles was evaluated using the Newcastle Ottawa scale. Out of the 817 identified citations, six studies fulfilled the eligibility criteria and were included in the systematic review. One study showed that children with mixed and permanent dentitions breastfed for more than 6 months presented greater mean protrusion of mandibular incisors and inclination of maxillary incisors compared with those breastfed for less than 6 months or those who were bottle-fed (p < 0.05). One study revealed that breastfeeding and bruxism were associated with Class II [OR = 3.14 (1.28 - 7.66)] and Class III [OR = 2.78 (1.21 - 6.36)] malocclusion in children with permanent dentition, while another study showed that an increase in breastfeeding duration was associated with a lower risk of malocclusion in children with both mixed and permanent dentitions (p < 0.001). Three studies did not report any significant association. Risk of bias was high in most selected articles. These findings do not support an association between breastfeeding and bottle feeding and the occurrence of malocclusion in mixed and permanent dentitions.

OrthoSystem: aplicativo de cálculo da análise da dentadura mista / Orthosystem: software for the mixed dentition analysis

Introdução: A análise da dentadura mista é essencial no diagnóstico em Ortodontia, uma vez que estima o tamanho dos dentes permanentes não irrompidos e verifica se o volume dentário estará de acordo com o tamanho da base óssea. Atualmente, existem softwares que realizam análise de modelos em 2D e 3D. Entretanto, esses programas ainda possuem um custo elevado. Objetivo: O objetivo deste estudo foi desenvolver um software (OrthoSystem), voltado para alunos de graduação e pós-graduação em Ortodontia, para efetuar a Análise de Modelos de Moyers. Método: Para avaliação da acurácia e do tempo despendido, utilizaram-se 60 pares de modelos de estudo que foram submetidos à Análise de Moyers manual e com o software. Para testar a usabilidade do programa, foram aplicados questionários a 72 graduandos de Odontologia da Universidade Federal do Rio Grande do Norte (UFRN). Resultado: O programa teve a acurácia validada, apresentando uma concordância perfeita (p=1) e um tempo de 4,20 minutos a menos para aferir a discrepância dos modelos em comparação com o método manual. Além disso, o OrthoSystem foi considerado de excelente usabilidade e melhor que o método convencional pelos alunos. Conclusão: Pode-se inferir que o software OrthoSystem realiza o que se propõe a fazer de forma correta e foi considerado um programa de excelente usabilidade pelos graduandos em odontologia da UFRN. .

Introduction: The analysis of mixed dentition is essential for diagnosis in Orthodontics to estimate size of unerupted permanent teeth and evaluate if the dental volume is in accordance with the arch lenght. Currently, there are softwares that perform the analysis of dental casts in 2D and 3D. However, these programs are still very expensive. Aim: The aim of this study was to develop a software (OrthoSystem) to be used by undergraduate and postgraduate orthodontics students to perform the mixed dentition analysis of Moyers. Method: To evaluate the accuracy and the time consumption, 60 pairs of dental casts were evaluated according Moyers analysis both manually and through the use of the software. Questionnaires were administered to 72 undergraduate Dentistry students to test the usability of the program. Result: The program had the accuracy validated, showing a perfect agreement (p = 1) and a time consuption of 4.2 minutes less when compared with the manual method to do the mixed dentition analysis. In addition, the OrthoSystem was considered excellent in usability and better than the conventional method by the students. Conclusion: The OrthoSystem software is efficient and was considered excellent for undergraduate Dentistry students. .

Prevalencia de trastornos temporomandibulares en niños mexicanos con dentición mixta / Prevalence of temporomandibular disorders in Mexican children with mixed dentition

Objetivo Determinar y contrastar con la bibliografía reportada, la prevalencia de trastornos temporomandibulares con un instrumento validado en dentición mixta de niños mexicanos. Métodos Se incluyeron 150 niños de 8 a 12 años de edad, de cualquier sexo que asistieron a la clínica de estomatología pediátrica de la BUAP, evaluados con los criterios diagnósticos para la Investigación de los TTM (CDI/TTM) por investigador previamente estandarizado (kappa=0,93). Los resultados se contrastaron con lo reportado en la bibliografía. Resultados La prevalencia de TTM fue del 20,7%, predominantemente de tipo muscular (77,4%), el 33,3% presentó alteración del patrón de apertura bucal, el 34% presentó ruidos articulares (chasquido), la función mandibular más comprometida fue el masticar (6%). Estos resultados contrastan con lo reportado en la bibliografía, específicamente en los sitios musculares doloridos y las cefaleas, probablemente explicado por los diferentes instrumentos utilizados. Conclusión La prevalencia de TTM es contrastante entre diversos estudios, es necesario enfatizar la necesidad de evaluar éstos durante la niñez y la juventud con instrumentos validados.(AU)

Objective To determine and compare with reports in the bibliography, the prevalence of temporomandibular disorders with an instrument validated for Mexican children with mixed dentition. Methods 150 children, from 8 to 12 years of age and of any sex who attended the pediatric stomatology clinic of the BUAP (Meritorious Autonomous University of Puebla) were included and evaluated with the diagnostic criteria for research on TTM (CDI/TTM) by a researcher who had been previously standardized (kappa=0.93). The results contrasted with reports in the bibliography. Results The prevalence of TTM was 20.7%. It was predominantly muscular (77.4%), though 33.3% showed alteration of the mouth-opening pattern, 34% showed joint noises (clicks). The most compromised mandibular function was chewing (6%). These results contrast with reports in the bibliography, specifically in terms of muscle pain sites and headaches, probably explained by different instruments used. Conclusion The prevalence of TTM is in contrast among different studies. It is necessary to place emphasis on the need to evaluate these factors during the childhood and adolescence with validated instruments.(AU)

Evaluation of two methods for mixed dentition analysis using the method error

AIM: In order to determine the reliability between two of these methodologically different method, this study evaluated the systematic and random errors of the method proposed by Tanaka and Johnston, which is based on the sum of mandibular permanent incisors, and the Huckaba method, which uses radiographs. METHODS: In a random sample of 28 plaster models of mandibular dental arches belonging to individuals of both genders, aged six to eleven years old, a single investigator performed the measurement of required space, according to the two methods evaluated. After 15 days, the measurements were repeated, and each of them was performed twice in sequence to calculate the repeatability and reproducibility conditions, and the systematic and random errors for each method. RESULTS: The random error of the method proposed by Huckaba was larger in terms of reproducibility (1.53 mm) and repeatability (0.57 mm) compared with the analysis proposed by Tanaka and Johnston (0.20 mm and 0.12 mm, respectively). CONCLUSIONS: The method proposed by Huckaba was proved to be inadequate in relation to reproducibility, with respect to the random error, and should be used with caution to measure the required space in the mandibular arch...

Condições socioeconômicas estão associadas ao overbite e overjet? Uma avaliação utilizando fotografias digitais / Are socioeconomic factors associated with overbite and overjet? An evaluation using digital photographs

OBJETIVO: estimar a associação entre fatores socioeconômicos e más oclusões do tipo overbite e overjet em escolares em fase de dentição permanente jovem. MÉTODO: trata-se de um estudo transversal realizado em 251 escolares de sete a 15 anos, de ambos os sexos, regularmente matriculadas no ensino fundamental de escolas públicas e privadas do município de São Luís, Maranhão, Brasil. Todos os sujeitos da amostra realizaram fotografias extrabucais padronizadas de face (frontal em repouso, frontal sorrindo e perfil) e intrabucais (frontal, lateral direita e lateral esquerda em oclusão, oclusal superior e oclusal inferior), para o diagnóstico das alterações. As fotografias foram avaliadas por três examinadores em regime cego e as discordâncias foram discutidas até a obtenção de consenso. Overbite e overjet foram diagnosticados segundo critérios de Angle. RESULTADOS: constatou-se que 35,4% das crianças apresentaram overbite e 18,3%, overjet. Houve associação estatisticamente significante entre a renda familiar com overbite (p=0.003) e com overjet (p=0.029), observando-se que a maioria das crianças que não possuíam overbite (69,4%) era de famílias com baixa renda (até 2 salários mínimos). De modo semelhante, a maioria dos portadores de overjet era de famílias com renda mais elevada, ao passo que a maioria daqueles sem overjet tinha renda familiar baixa. Para as demais variáveis não houve diferenças estatisticamente significante na distribuição de frequência de overjet e overbite. CONCLUSÃO: a prevalência de overbite e overjet nos escolares estudados é alta, especialmente entre aqueles com maior renda familiar.

PURPOSE: to estimate the association between socioeconomic factors and occlusal changes like overbite and overjet in students aged 7 to 15 years. METHOD: this is a cross-sectional study in 251 students of both gender regularly enrolled in the school of public and private schools in São Luís, Maranhão, Brazil. All subjects carried out the sample photos extra-oral standardized face (front resting, smiling front and profile) and intraoral (front, right side and left side in occlusion, occlusal upper and lower occlusal) for the diagnosis of changes. The photographs were evaluated by three observers under blind and disagreements were discussed to achieve consensus. Overbite and overjet were diagnosed according to criteria of Angle. RESULTS: it was found that 35.4% of the children were 18.3% and overbite, overjet. There was a statistically significant association between family income and overbite (p = 0.003) and overjet (p = 0.029), noting that most children who had no overbite (69.4%) were low-income families (up to 2 minimum wage). Similarly, most people with overjet were families with higher incomes, while the majority of those without overjet had low family income. For other variables there was no statistically significant difference in frequency distribution of overjet and overbite. CONCLUSION: the prevalence of overbite and overjet among the studied population is high, especially among those with higher family income.