Biomechanical and chemical behavior of various bioactive materials in class II restorations / Desempeño biomecánico y químico de diferentes materiales bioactivos en restauraciones clase II

The aim of this in vitro study was to evaluate the biomechanical and chemical behavior of various bioactive materials in class II MOD restorations. Forty- eight standardized class II MOD cavities were prepared in sound extracted human molar teeth. The specimens were divided into four groups according to the restorative material: Group 1 (Filtek™ Z350 XT), Group 2 (Biodentine™ as a liner, and then restored with Filtek™ Z350 XT), Group 3 (Cention N™), and Group 4 (Activa™ Bioactive-Restorative). The samples were tested for fracture resistance by subjecting them to a compressive load in a Universal testing Machine. The failure modes of each specimen were evaluated. The alkalinizing potential and calcium ion release of the materials were measured. SEM-EDAX analyses were also performed for all materials. Data were analyzed using ANOVA and post hoc Tukey test (p<0.05). Group 1 showed the higher fracture resistance (p<0.05). Group 3 had greater fracture resistance values but no statistical difference from Group 4. Biodentine™ showed greater biomineralization potential. Class II MOD restorations of Group 1 displayed the higher fracture resistance; however, it was highly associated with catastrophic failure. Conversely, Biodentine™ presented a more significant bioactivity potential, and its use, as in Group 2, promoted the most favorable failure mode.

El objetivo de este estudio, in vitro, fue evaluar el desempeño biomecánico y químico de varios materiales bioactivos en restauraciones clase II MOD. Se prepararon cuarenta y ocho cavidades clase II MOD estandarizadas en dientes molares humanos extraídos. Las muestras se dividieron en cuatro grupos según el material de restauración: Grupo 1 (Filtek™ Z350 XT), Grupo 2 (Biodentine™ como base y luego restaurado con Filtek™ Z350 XT), Grupo 3 (Cention N™) y Grupo 4 (Activa™ Bioactivo-Reparador). La prueba de resistencia a la fractura fue realizada en una máquina de ensayo universal Instron. Se evaluaron los modos de falla de cada espécimen. Se midió el pH y la liberación de iones de calcio de los materiales. Se realizaron análisis SEM-EDAX. Los datos se analizaron mediante ANOVA y la prueba post hoc de Tukey (p<0,05). El grupo 1 mostró la mayor resistencia a la fractura (p<0,05). El Grupo 3 tuvo mayores valores de resistencia a la fractura que el Grupo 4, pero sin diferencia estadística. Biodentine™ mostró un mayor potencial de biomineralización. Las restauraciones Clase II MOD del Grupo 1 mostraron la mayor resistencia a la fractura; sin embargo, estuvo altamente asociado con fallas irreparables. Por el contrario, Biodentine™ presentó un potencial de bioactividad más significativo y su uso, como en el Grupo 2, promovió el modo de falla más favorable.

Inhibition of ANGPT2 activates autophagy during hypertrophic scar formation via PI3K/AKT/mTOR pathway

Abstract Background Hypertrophic scar (HS), a fibroproliferative disorder caused by aberrant wound healing following skin injuries such as burns, lacerations and surgery, is characterized by invasive proliferation of fibroblasts and excessive extracellular matrix (ECM) accumulation. The dysregulation of autophagy is the pathological basis of HS formation. Previously, angiopoietin-2 (ANGPT2) was found to be overexpressed in HS fibroblasts (HSFs) compared with normal skin fibroblasts. However, whether ANGPT2 participates in the process of HS formation and the potential molecular mechanisms are not clear. Objective This study is intended to figure out the role of ANGPT2 and ANGPT2-mediated autophagy during the development of HS. Methods RT-qPCR was used to detect ANGPT2 expression in HS tissues and HSFs. HSFs were transfected with sh-ANGPT2 to knock down ANGPT2 expression and then treated with MHT1485, the mTOR agonist. The effects of sh-ANGPT2 or MHT1485 on the proliferation, migration, autophagy and ECM accumulation of HSFs were evaluated by CCK-8 assay, Transwell assay and western blotting. The expression of PI3K/Akt/mTOR pathway-related molecules (p-PI3K, p-Akt and p-mTOR) was assessed by western blotting. Results ANGPT2 expression was markedly upregulated in HS tissues and HSFs. ANGPT2 knockdown decreased the expression of p-PI3K, p-Akt and p-mTOR. ANGPT2 knockdown activated autophagy and inhibited the proliferation, migration, and ECM accumulation of HSFs. Additionally, the treatment of MHT1485, the mTOR agonist, on ANGPT2-downregulated HSFs, partially reversed the influence of ANGPT2 knockdown on HSFs. Study limitations The study lacks the establishment of more stable in vivo animal models of HS for investigating the effects of ANGPT2 on HS formation in experimental animals. Conclusions ANGPT2 downregulation represses growth, migration, and ECM accumulation of HSFs via autophagy activation by suppressing the PI3K/Akt/mTOR pathway. Our study provides a novel potential therapeutic target for HS.

Management of ankylosed teeth using the decoronation technique: integrative literature review and case report

ABSTRACT Introduction: The decoronation technique has been described in literature since 1984 and, based on the available results, it can lead to considerable benefits for the repair and rehabilitation of ankylosed teeth. Based on these reports, one could expect that this procedure would be well known by the dental community. However, this fact does not seem to be true, and this procedure is not widely used. Methods: The objective of this paper is to present appropriate literature that discusses decoronation and evaluate the perspectives of the procedure, both in relation to the technique and the long-term benefits for the patient. An integrative literature review at PubMed, ScieELO, and Lilacs databases was performed using the keywords "decoronation", "ridge preservation decoronation", "decoronation ankylosis". In addition, a case report will be presented to demonstrate the technique in a systematic and detailed manner. Results: Considering the inclusion criteria, 27 articles that present consistency regarding decoronation were selected. Conclusion: There is scarce availability of scientific works related to the topic, to corroborate and discuss the technique. The present paper reinforces the benefits of this procedure, and revisit decoronation, attempting to provide a possible treatment for ankylosed teeth in growing patients.

RESUMO Introdução: A técnica de decoronação é descrita na literatura desde 1984 e, com base nos resultados disponíveis, pode trazer benefícios consideráveis para o reparo e reabilitação de dentes anquilosados. Com base nesses relatos, seria esperado que esse procedimento fosse bem conhecido pela comunidade odontológica. No entanto, isto não parece ser verdadeiro e esse procedimento não é amplamente utilizado. Objetivo: O objetivo deste artigo é apresentar literatura adequada que discuta a decoronação e avalie as perspectivas do procedimento, tanto em relação à técnica quanto aos benefícios em longo prazo para o paciente. Métodos: Foi realizada revisão integrativa da literatura nas bases de dados PubMed, SciELO e Lilacs, utilizando as seguintes palavras-chave: "decoronation", "ridge preservation decoronation", "decoronation ankylosis". Além disso, um relato de caso demonstrará a técnica de maneira sistemática e detalhada. Resultados: Considerando os critérios de inclusão, foram selecionados 27 artigos que apresentam consistência quanto à decoronação. Conclusão: Há escassa disponibilidade de trabalhos científicos relacionados ao tema para corroborar e discutir a técnica. Esse artigo reforça os benefícios desse procedimento e revisa a decoronação na tentativa de fornecer um possível tratamento para dentes anquilosados em pacientes em crescimento.

Cephalometric comparison of mandibular growth in Brazilian children with Class II malocclusion and normal occlusion during the growth stages determined by the cervical vertebrae maturation

ABSTRACT Objective: This study compared mandibular growth in children, aged 7 to 12 years, with Class II malocclusion and normal occlusion, between the following stages of cervical vertebrae maturation: initiation (I), acceleration (A), transition (T). Material and Methods: A total of 148 lateral cephalograms (78 males, 70 females) of Class II malocclusion patients, and 60 lateral cephalograms (30 males, 30 females) of normal occlusion patients were included. The following linear cephalometric measurements were performed: Co-Gn (effective mandibular length), Co-Go (ramus height), and Go-Gn (length of mandibular body). Mean values of increments between stages (I-A, A-T, I-T) were obtained for each group and gender. Results were compared using the Student t-test, and a significance level of 0.05% was adopted. Results: Females group: A-T interval presented a greater increment in Co-Go in the Class II group, which was not significant for the I-T interval, with numerically smaller increments in Co-Gn and Go-Gn, without statistical significance. Males group: intervals I-A, A-T and I-T showed numerically smaller growth increments in the Class II group, with statistical significance for Co-Gn in I-A (p=0.001) and I-T (p=0.003). Comparing genders of the Class II group, Co-Go was higher in males (p=0.002) and I-T interval (p=0.031). In the Normal Occlusion group, the male gender had the greatest Co-Gn (p=0.038) for the I-A interval. In A-T and I-T, Co-Go in males was higher, with statistical significance (p=0.000 and p=0.002, respectively). Conclusion: Growth phenomenon affects the mandibular dimensions regardless of the character of the malocclusion, with a tendency to be smaller in the presence of Class II malocclusion.

RESUMO Objetivo: Esse estudo comparou o crescimento mandibular em crianças de 7 a 12 anos de idade, com má oclusão de Classe II ou Oclusão Normal, entre os seguintes estágios de maturação das vértebras cervicais: iniciação (I), aceleração (A), transição (T). Material e Métodos: No total, 148 telerradiografias laterais (78 meninos, 70 meninas) de pacientes com má oclusão de Classe II e 60 telerradiografias laterais (30 meninos, 30 meninas) de pacientes com Oclusão Normal foram avaliadas. As medidas cefalométricas lineares Co-Gn (comprimento mandibular efetivo), Co-Go (altura do ramo mandibular) e Go-Gn (comprimento do corpo mandibular) foram analisadas e os valores médios dos incrementos entre os estágios (I-A, A-T e I-T) foram obtidos para cada grupo e sexo. Resultados: Os resultados foram comparados pelo teste t de Student, e o nível de significância adotado foi de 0,05%. Sexo feminino: houve maior incremento na altura do ramo no grupo Classe II em A-T, que diminuiu em I-T, com menores incrementos no comprimento mandibular efetivo e no corpo mandibular, sem significância estatística. Para o sexo masculino, nos intervalos I-A, A-T, I-T, os incrementos de crescimento foram numericamente menores no grupo Classe II, com significância estatística para o comprimento efetivo da mandíbula em I-A (p= 0,001) e em I-T (p= 0,003). No grupo Classe II, a altura do ramo foi maior para o sexo masculino (p= 0,002) e no intervalo I-T (p= 0,031). No grupo Oclusão Normal, o sexo masculino apresentou o maior comprimento mandibular efetivo (p= 0,038) no intervalo I-A. Nos intervalos A-T e I-T, a altura do ramo mandibular no sexo masculino foi maior e com significância estatística de p= 0,000 e p= 0,002, respectivamente. Conclusão: O fenômeno do crescimento afeta as dimensões mandibulares independentemente do característica da má oclusão, com tendência a ser menor na presença da má oclusão de Classe II.

Evaluation of the maximum tongue and lip pressure in individuals with Class I, II, or III Angle malocclusions and different facial types / Avaliação da pressão máxima da língua e dos lábios em indivíduos com má oclusão Classe I, II e III de Angle e diferentes padrões faciais

ABSTRACT Purpose To compare the maximum anterior and posterior tongue pressure, tongue endurance, and lip pressure in Class I, II, and III malocclusions and different facial types. Methods A cross-sectional observational analytical study was carried out in 55 individuals (29 men and 26 women) aged between 18 and 55 years. The participants were divided into groups according to Angle malocclusion (Class I, II, and III) and facial type. The maximum anterior and posterior tongue pressure, tongue endurance, and maximum lip pressure were measured using the IOPI (Iowa Oral Performance Instrument). To determine the facial type, the cephalometric analysis was accomplished using Ricketts VERT analysis as a reference. Results There was no statistically significant difference when comparing the maximum pressure of the anterior and posterior regions of the tongue, the maximum pressure of the lips, or the endurance of the tongue in the different Angle malocclusion types. Maximum posterior tongue pressure was lower in vertical individuals than in mesofacial individuals. Conclusion Tongue and lips pressure, as well as tongue endurance in adults was not associated with the type of malocclusion. However, there is an association between facial type and the posterior pressure of the tongue.

RESUMO Objetivo comparar a pressão máxima anterior e posterior da língua, a resistência da língua e a pressão labial em indivíduos com más oclusões Classe I, II e III e diferentes tipos faciais. Método foi realizado um estudo analítico observacional transversal em 55 indivíduos (29 homens e 26 mulheres) com idades entre 18 e 55 anos. Os participantes foram divididos em grupos de acordo com a classificação de Angle para má oclusão (Classe I, II e III) e tipo facial. A pressão máxima anterior e posterior da língua, a resistência da língua e a pressão máxima dos lábios foram medidas usando o IOPI (Iowa Oral Performance Instrument). Para determinar o tipo facial, a análise cefalométrica foi realizada utilizando como referência a análise Ricketts VERT. Resultados não houve diferença estatisticamente significativa ao comparar a pressão máxima das regiões anterior e posterior da língua, a pressão máxima dos lábios ou a resistência da língua nos diferentes tipos de má oclusão. A pressão máxima posterior da língua foi menor em indivíduos com tipo facial vertical do que nos indivíduos mesofaciais. Conclusão a pressão de língua e lábios, assim como a resistência de língua em adultos não foi associada ao tipo de má oclusão. No entanto, existe uma associação entre o tipo facial e a pressão posterior da língua.

Orthodontic biomechanics with intermaxillary elastics

ABSTRACT Introduction: Intermaxillary elastics are orthodontic resources widely used in various malocclusions. Their main advantages are low cost, easy insertion and removal by patients, and application versatility. As main disadvantages, we can highlight the need for cooperation from patients and the side effects normally present in treatments with this resource. Knowledge of the biomechanics involved in the use of intermaxillary elastics is essential to take full advantage of the desired effects and avoid unwanted effects in their use. Objective: Therefore, the objective of this article is to describe the anchorage preparation, connection methods, time and force of use, and side effects involved in the use of intermaxillary elastics for the treatment of anteroposterior, vertical and transverse problems. For that, clinical cases and biomechanics schemes will be presented, in which all these details will be described.

RESUMO Introdução: Os elásticos intermaxilares são recursos ortodônticos amplamente utilizados nas diversas más oclusões. Possuem como principais vantagens o baixo custo, fácil inserção e remoção pelos pacientes, e versatilidade de aplicação. Como desvantagens podemos destacar a necessidade de cooperação dos pacientes e os efeitos colaterais normalmente presentes nos tratamentos com esse recurso. O conhecimento da biomecânica envolvida no uso dos elásticos intermaxilares é fundamental para se obter o máximo de efeitos desejados e evitar os efeitos indesejados na sua utilização. Objetivo: O objetivo desse artigo é descrever o preparo da ancoragem, as formas de conexão, o tempo e a força de uso, além dos efeitos colaterais envolvidos na utilização dos elásticos intermaxilares para tratamento de problemas anteroposteriores, verticais e transversais. Para isso, serão apresentados casos clínicos e esquemas de biomecânica em que todos esses detalhes serão descritos.

One-year clinical evaluation of class II bulk-fill restorations in primary molars: a randomized clinical trial

Abstract This double-blind, randomized clinical trial aimed to compare the clinical performance and clinical time to restore occluso-proximal cavities in primary molars withbulk-fillresin and conventional resin. A total of 140 class II restorations in primary molars of 65 participants (mean age of 6.7 + 1.5) were placed in two random groups:bulk-filland conventional resin. The restorations were evaluated using FDI criteria at the baseline, 6-month, and one year by a single calibrated examiner, and the clinical restorative time was measured with a digital timer. The success and survival of the restorations were evaluated with Kaplan-Meier graphs. The log-rank test compared the curves. Differences in restorative clinical time were compared using the Mann-Whitney U test. The level of significance was 5%. After one year, 115 restorations were evaluated. The success probability was 88.7% for Filtek Z350 XT and 85.9% for FiltekTM Bulk-fill, and for the survival probability, Filtek Z350 XT presented 90%, and FiltekTM Bulk-fill presented 93.7%. No significant difference was found between the success and survival curves (p=0.62), (p=0.51). The main reason for failure was marginal adaptation.Bulk-fillresinrequired 30% less time than the conventional resin (p<0.001).Bulk-fillresin presented similar clinical performance to the conventional resin and required less restorative clinical time. It is an option to restore class II lesions of primary molars.

Resumo Este ensaio clínico randomizado, duplo-cego objetivou comparar a performance clínica e tempo clínico para restaurar cavidades ocluso-proximais em molares decíduos, restauradas com resina bulk-fill e resina convencional. Um total de 140 restaurações classe II em molares decíduos de 65 participantes (média de idade 6.7 + 1.5) foram realizadas dividas em dois grupos randomizados: resina bulk-fill e resina convencional. As restaurações foram avaliadas conforme o critério da FDI no baseline, após 6 meses e 1 ano, por um único examinador calibrado e o tempo clínico restaurador foi mensurado por um cronômetro digital. O sucesso e a sobrevida das restaurações foram avaliados através dos gráficos de Kaplan-Meier. O teste de log-rank comparou as curvas. A diferença no tempo clínico restaurador foi comparada usando o teste U de Mann-Whitney. O nível de significância foi de 5%. Após 1 ano, 115 restaurações foram avaliadas. A probabilidade de sucesso foi de 88,7% para Filtek Z350 XT e 85.9% para FiltekTM Bulk-fill e quanto a probabilidade de sobrevivência, Filtek Z350 XT apresentou 90% e FiltekTM Bulk-fill apresentou 93,7%. Não foi encontrada diferença significativa entre as curvas de sucesso e sobrevida (p=0,62), (p=0,51). A principal causa de falha foi a adaptação marginal. A resina bulk-fill exigiu 30% menos tempo do que a resina convencional (p<0,001). A resina bulk-fill apresentou desempenho clínico semelhante ao da resina convencional e necessitou menor tempo clínico restaurador. Dessa forma, é uma opção para restaurar lesões classe II em molares decíduos.

Human leukocyte antigen Class II alleles associated with acral lentiginous melanoma in Mexican Mestizo patients: A case-control study

Background: Melanoma is an aggressive cutaneous cancer. Acral lentiginous melanoma is a melanoma subtype arising on palms, soles, and nail-units. The incidence, prevalence and prognosis differ among populations. The link between expression of major histocompatibility complex Class II alleles and melanoma progression is known. However, available studies report variable results regarding the association of melanoma with specific HLA Class II loci. Aims: The aim of the study was to determine HLA Class II allele frequencies in acral lentiginous melanoma patients and healthy Mexican Mestizo individuals. Methods: Eighteen patients with acral lentiginous melanoma and 99 healthy controls were recruited. HLA Class II typing was performed based on the sequence-specific oligonucleotide method. Results: Three alleles were associated with increased susceptibility to develop acral lentiginous melanoma, namely: HLA-DRB1*13:01; pC = 0.02, odds ratio = 6.1, IC95% = 1.4–25.5, HLA-DQA1*01:03; pC = 0.001, odds ratio = 9.3, IC95% = 2.7–31.3 and HLA-DQB1*02:02; pC = 0.01, odds ratio = 3.7, IC95% = 1.4–10.3. Limitations: The small sample size was a major limitation, although it included all acral lentiginous melanoma patients seen at the dermatology department of Dr. Manuel Gea González General Hospital during the study period. Conclusion: HLA-DRB1*13:01, HLA-DQB1*02:02 and HLA-DQA*01:03 alleles are associated with increased susceptibility to develop acral lentiginous melanoma in Mexican Mestizo patients.

Orthodontists' preferences in the use and timing of appliances for the correction of malocclusions in growing patients / Preferencias de los ortodoncistas en el uso y momento oportuno de uso de aparatos para la corrección de maloclusiones en pacientes en crecimiento

Objective: To evaluate orthodontists' preferences in the use and timing of appliances for the correction of Class II and Class III malocclusions in growing patients and the sociodemographic factors that influence these preferences. Material and Methods: Active members of the Colombian Orthodontics Society (SCO) were invited to complete a previously validated survey on the use of Class II and Class III correctors in growing patients. Results: 180 orthodontists responded (80 male, 100 female). The appliances used most frequently in the treatment of Class II malocclusion were Planas indirect tracks (32.78%) and Twin-blocks (30.56%). Facemasks (62.22%) and Progenie plates (25%) were the most prevalent appliances used in the treatment of Class III malocclusions. Regarding treatment timing, 52% of the orthodontists stated that Class II malocclusions must be treated during late mixed dentition or early permanent dentition, 42% stated that treatment for Class III malocclusions should occur during early mixed dentition. Appliance use and treatment timing were significantly associated with sex (p= 0.034), years of practice (p= 0.025), and area of work (private clinics or public institutions), (p= 0.039). Conclusion: Twin-blocks and Facemask appliances were the preferred appliances for Class II and Class III treatment, respectively, in growing patients. Most of the orthodontists believed that Class II malocclusions must be treated during late mixed dentition and that Class III malocclusions must be treated during early mixed dentition. Sociodemographic variables are related factors that influence orthodontists' preferences in the use of these appliances.

Objetivo: Evaluar las preferencias de los ortodoncistas en el uso y momento oportuno de uso de aparatología para la corrección de maloclusiones Clase II y Clase III en pacientes en crecimiento y los factores sociodemográficos que influyen en estas preferencias. Material y Métodos: Se invitó a miembros activos de la Sociedad Colombiana de Ortodoncia (SCO) a completar una encuesta previamente validada, sobre el uso de correctores para Clase II y Clase III en pacientes en crecimiento. Resultados: Respondieron un total de 180 ortodoncistas (80 hombres, 100 mujeres). La aparatología más utilizada en el tratamiento de las maloclusiones de Clase II fueron pistas indirectas de Planas (32,78%) y bloques gemelos (30,56%). La máscara facial (62,22%) y las placas progenie (25%) fueron los aparatos más utilizados en el tratamiento de las maloclusiones de Clase III. En cuanto al momento oportuno del tratamiento, el 52% de los ortodoncistas afirmó que las maloclusiones de Clase II deben tratarse durante la dentición mixta tardía o la dentición permanente temprana, el 42% afirmó que el tratamiento para las maloclusiones de Clase III debe ocurrir durante la dentición mixta temprana. El uso de aparatos y el momento oportuno del tratamiento se asociaron significativamente con el sexo (p= 0,034), los años de práctica (p= 0,025) y el área de trabajo (clínicas privadas o instituciones públicas) (p= 0,039). Conclusión: Los aparatos bloques gemelos y la máscara facial fueron los preferidos para el tratamiento de Clase II y Clase III, respectivamente, en pacientes en crecimiento. La mayoría de los ortodoncistas consideran que las maloclusiones de Clase II deben tratarse durante la dentición mixta tardía y que las maloclusiones de Clase III deben tratarse durante la dentición mixta temprana. Las variables sociodemográficas son factores relacionados que influyen en las preferencias de los ortodoncistas en el uso de estos aparatos.

Cambios en incisivos y su relación con el punto A y el ángulo nasolabial en pacientes Clase II división 2 tratados con y sin extracciones en el Centro Dental Docente UPCH / Changes in incisors and their relationship with point A and nasolabial angle in Class II division 2 patients treated with and without extractions at the UPCH Teaching Dental Center

RESUMEN Antecedentes : Diversos estudios describen las características de la maloclusión clase II-2, sin embargo, son escasos los estudios que evalúan las repercusiones del tratamiento sobre tejidos blandos y esqueléticos. Objetivo : Evaluar los cambios post tratamiento en inclinación y posición incisiva y su relación con el ángulo nasolabial (ANL) y el punto A (PA) en pacientes Clase II división 2, con y sin extracciones en casos de la especialidad de Ortodoncia de la Universidad Peruana Cayetano Heredia. Material y métodos: se realizaron trazados manuales y mediciones de 62 radiografías cefalométricas laterales (31 pre y 31 post-tratamiento), de pacientes con maloclusión de Clase II división 2. El análisis estadístico se realizó con SPSS 21.0 para Windows. Resultados : Se observan proinclinación y protrusión incisiva en todos los pacientes. En pacientes con exodoncias el ANL presentó cambios no significativos, pero correlaciones significativas: cuando aumentó la inclinación incisiva inferior disminuyó el ANL; cuando aumentó el ANL, aumentó el ángulo interincisal (AII). El punto A (PA) experimentó cambios y correlaciones, pero no significativas. En pacientes sin exodoncias no se encontraron correlaciones ni cambios significativos en PA ni en ANL. Las mujeres tratadas sin exodoncia no presentaron cambios significativos, en los hombres los cambios más significativos fueron la inclinación y protrusión incisiva inferior. En los casos con exodoncias en hombres fue el AII; y en las mujeres el AII y el ángulo incisivo superior/ plano palatino. Conclusiones: Existe una relación entre los cambios que se producen en los incisivos y el ANL y PA, aunque la mayoría no son estadísticamente significativos.

ABSTRACT Background : There are studies evaluating cephalometric parameters in Class II division 2 patients. There are no similar investigations in Peru. Objective : To evaluate post-treatment changes in incisor inclination and position and their relationship with the nasolabial angle (ANL) and point A (PA) in Class II division 2 patients, with and without extractions in cases of the Orthodontic specialty program of the Universidad Peruana Cayetano Heredia. Material and methods : manual tracing and measurements of 62 lateral cephalometric radiographs (31 pre and 31 post-treatment) were performed, of patients with Malocclusion Class II division 2. Statistical analysis was performed with SPSS 21.0 for Windows. Results : There was proinclination and incisive protrusion in all patients. In patients with extractions, the ANL presented non-significant changes, but significant correlations: when the lower incisor inclination increased, the ANL decreased; when ANL increased, the interincisal angle (AII) increased. Point A (PA) experienced changes and correlations, but not significant. In patients without extractions, no correlations or significant changes were found in BP or ANL. Women treated without extraction did not show significant changes, in men the most significant changes were lower incisor inclination and protrusion. In the cases with extractions in men it was AII; and in women the AII and the upper incisor angle / palatal plane. Conclusions: There is a relationship between the changes that occur in the incisors and the ANL and PA, although most are not statistically significant.

Status Analysis and Improvement Suggestions on Filing Review Trial Implementation of Shanghai's Class II Passive Medical Device Registration / 中国医疗器械杂志

This article collected the statistics of Shanghai's class II passive medical device registration filing review trial implementation. It summarized and analyzed the common issues in the filing review stage, and gave suggestions for registration applicants and reviewers in order to further improve the quality of application materials and improve the efficiency of review.

Utilización del botón de Nance modificado para la propulsión mandibular / Utilization of the modified Nance button for mandibular propulsion

RESUMEN Introducción: En sus inicios la mayoría de los aparatos funcionales fueron removibles, pero cada día más se incrementan los fijos. Su combinación puede incrementar la eficacia en el tratamiento del retrognatimo mandibular. Objetivo: Presentar los resultados del tratamiento con el botón de Nance modificado en una paciente con retrognatismo mandibular. Caso clínico: Paciente femenina de 13 años de edad, que presenta perfil convexo, disfunción neuromuscular, dentición permanente en ambos maxilares con presencia de ligero apiñamiento anterior, relación molar bilateral de distoclusión de ½ unidad, resalte y sobrepase incisivos de 6 mm, mala relación intermaxilar causada por retrognatismo de la mandíbula y escaso remanente de crecimiento mandibular activo. La primera etapa del tratamiento, incluyó psicoterapia, mioterapia y avance mandibular con un aparato funcional fijo (botón de Nance modificado para la propulsión mandibular). A los nueve meses de iniciar el tratamiento se comprobó el cambio en las relaciones intermaxilares en sentido antero-posterior, con disminución del ángulo ANB hasta 20 e incremento del SNB a 78, como reflejo de una buena relación de las bases ósea por crecimiento mandibular. Conclusiones: El tratamiento realizado a la paciente con el botón de Nance modificado para la propulsión mandibular, permitió la obtención de relaciones intermaxilares favorables.

ABSTRACT Introduction: In the beginning, most of the functional appliances were removable, but the fixed ones are increasing every day. Their combination can increase the effectiveness in the treatment of mandibular retrognathymus. Objective: To present the results of the treatment of a patient with mandibular retrognathism treated with the modified Nance button. Case report: A 13-year-old female patient with convex profile, neuromuscular dysfunction, permanent dentition in both jaws with the presence of slight anterior crowding, bilateral distoclusion molar ratio of ½ unit, incisor protrusion and overhang of 6 mm, poor intermaxillary relationship caused by retrognathism of the mandible and little remnant of active mandibular growth. The first stage of treatment included psychotherapy, myotherapy and mandibular advancement with a fixed functional appliance (modified Nance button for mandibular propulsion). Nine months after starting the treatment, the change in the intermaxillary relationships in the anteroposterior direction was verified, with a decrease in the ANB angle to 20 and an increase in the SNB to 78, as a reflection of a good relationship of the bone bases due to mandibular growth. Conclusions: One year after treatment with the modified Nance button for mandibular propulsion, a correct relationship of the patient's bone bases was achieved.

Long term dental transversal stability of Class II division 1 treated with cervical headgear

ABSTRACT Introduction: In several conditions, outcome stability is a great challenge for Orthodontics. Previous studies have reported that relapse commonly occurs along the years after orthodontic treatment finishing. Objective: The aim of the present study was to evaluate in the long-term transversal dental arch changes of Class II division 1 patients treated with cervical headgear and fixed appliance. Methods: Plaster study casts of 20 patients treated with cervical headgear without dental extractions were 3D-scanned and evaluated in three distinct times: initial (T1), immediate post-treatment (T2) and long-term retention (T3 - minimum 20 years). Transversal teeth distance of maxillary and mandibular canines, premolars and first molars were measured. Results: A statistically significant increase during treatment was observed for all maxillary teeth transversal distances (p< 0.05). In turn, a significant reduction was observed in the long term (p<0.05). For the mandibular teeth, canine transversal distance presented statistically significant constriction in the retention period (p<0.05). Mandibular first molars distance was significantly expanded by treatment (p<0.05) and remained stable in the long term. The changes observed for the other teeth or other times were considered not statistically relevant. Conclusions: For the accessed sample, transversal changes occurred during treatment and retention phases in Class II division 1 patients treated with cervical headgear and fixed appliance. Relapse was considered statistically relevant, even with the institution of a retention protocol.

RESUMO Introdução: Em várias condições, a estabilidade dos resultados é um grande desafio para a Ortodontia. Estudos prévios relataram que a recidiva ocorre, comumente, ao longo dos anos, após o término do tratamento ortodôntico. Objetivo: O objetivo da presente pesquisa foi avaliar as alterações transversais da arcada dentária em longo prazo de pacientes Classe II, divisão 1, tratados com aparelho extrabucal cervical e aparelho fixo. Métodos: Modelos de gesso de 20 pacientes tratados com AEB cervical, sem extrações dentárias, foram escaneados e avaliados em três momentos distintos: inicial (T1), pós-tratamento imediato (T2) e acompanhamento de longo prazo (T3, mínimo de 20 anos). A distância transversal entre os caninos superiores e inferiores, pré-molares e primeiros molares foi medida. Resultados: Foi observado aumento estatisticamente significativo durante o tratamento para todas as distâncias transversais dos dentes superiores (p < 0,05). Por sua vez, foi observada redução significativa em longo prazo (p < 0,05). Para os dentes inferiores, a distância transversal intercaninos apresentou constrição estatisticamente significativa no período de contenção (p < 0,05). A distância dos primeiros molares inferiores aumentou significativamente com o tratamento (p < 0,05) e permaneceu estável em longo prazo. As alterações observadas para os outros dentes ou outros tempos foram consideradas sem significância estatística. Conclusões: Para a amostra estudada, as alterações transversais ocorreram durante as fases de tratamento e contenção em pacientes Classe II, divisão 1, tratados com aparelho extrabucal de tração cervical e aparelho fixo. A recidiva foi considerada estatisticamente significativa, mesmo com a instituição de um protocolo de contenção.

Nuevas opciones de aparatos funcionales para tratar pacientes con retrognatismo mandibular / New functional appliance options for treating patients with mandibular retrognathia

RESUMEN Fundamento: El estudio sobre los aparatos actuales de la ortopedia funcional de los maxilares puede aportar nuevos conocimientos para el perfeccionamiento del tratamiento de pacientes con retrognatismo mandibular. Objetivo: Profundizar en los nuevos aparatos de la ortopedia funcional de los maxilares para el tratamiento de pacientes con retrognatismo mandibular. Desarrollo: Se realizó una revisión bibliográfica en las bases de datos SciELO, PubMed, Ebsco, Cumed y Lilacs. En la búsqueda se revisaron 37 artículos, de ellos más del 80 % son de los últimos cinco años. Se identificaron bases teóricas de la ortopedia funcional de los maxilares en el tratamiento de pacientes con retrognatismo mandibular y los aparatos que se utilizan en la actualidad. Conclusiones: Existen nuevas opciones de aparatos funcionales, en su mayoría fijos y clasificados como dentosoportados pasivos, para el tratamiento de pacientes con retrognatismo mandibular.

ABSTRACT Background: The study of the current jaw functional orthopedic appliances can provide new knowledge for the improvement of the patients' treatment with mandibular retrognathia. Objective: To study deeply the current jaw functional orthopedic appliances for the patients' treatment with mandibular retrognathia. Development: A bibliographic review was conducted in the SciELO, PubMed, Ebsco, Cumed and Lilacs databases. A total of 37 articles were reviewed, more than 80 % from the last five years. Theoretical bases on the jaw functional orthopedics in the patients' treatment with mandibular retrognathia and current appliances in use were identified. Conclusions: New functional appliance options, mostly fixed and classified as passive dent supportive, are available for the patients' treatment with mandibular retrognathia.

Differential Diagnosis of Skeletal Class II: Orthodontic-Surgical Approach with Surgery First / Diagnóstico Diferencial da Classe II esquelética: Abordagem Ortodôntico-Cirúrgica com Benefício Antecipado

Abstract Orthodontic-surgical treatment with the "Surgery First Approach" provides immediate facial aesthetic improvements and significantly reduces the patient's orthodontic treatment time, avoiding the transient worsening of the facial profile due to dental decompensation that occurs in surgical cases. Thus, this clinical case describes the retreatment of a 22-year-old female leukoderma patient, whose main complaint was related to the proclination of upper and lower incisors. The patient used a mio-relaxing plate for 30 days, which evidenced the skeletal mandibular deficiency and the ½ bilateral Class II malocclusion. Orthognathic surgery first approach associated with the extraction of the 4 premolars was chosen considering the patient's aesthetic demand. The use of a mio-relaxing plate in the diagnostic stage was essential for the real diagnosis of mandibular deficiency and the technique employed made it possible to conclude the treatment avoiding aesthetic commitment, with excellent results. (AU)

Resumo O tratamento ortodôntico-cirúrgico por meio do benefício antecipado proporciona melhorias estéticas faciais imediatas e reduz de maneira significativa o tempo de tratamento ortodôntico do paciente, evitando a piora transitória do perfil facial devido à descompensação dentária que ocorre em casos cirúrgicos. Assim, este caso clínico descreve o retratamento de uma paciente com 22 anos de idade, leucoderma, sexo feminino, que apresentava queixa principal relacionada à inclinação vestibular dos dentes anteriores. Após uso de placa miorrelaxante por 30 dias, verificou-se a presença de Classe II esquelética com deficiência mandibular e ½ Classe II dentária bilateral. Considerando a demanda estética da paciente, optou-se pela abordagem ortodôntico-cirúrgica com Benefício Antecipado associada à extração de 4 pré-molares para correção da inclinação dentária anterior. O uso da placa miorrelaxante foi fundamental para o diagnóstico real da deficiência mandibular e a técnica empregada possibilitou concluir o tratamento evitando o comprometimento estético pré-cirúrgico, com obtenção de excelentes resultados. (AU)

Evaluation of the clinical effectiveness of miniscrews in class i and ii malocclusion patients: a systematic review and meta-analysis

Aim: The present systematic review and meta-analysis aimed to evaluate the clinical effectiveness of miniscrews in Class I and II Malocclusion Patients. Methods: From electronic databases, between 2010 and 2020, PubMed, Embase, Cochrane Library, ISI were used to conduct systematic literature. Two reviewers extracted data blindly and independently from the abstract and full text of the studies they used for data extraction. The mean differences between the two groups (miniscrews vs. conventional anchorage) with a 95 % confidence interval (CI), the Inverse-variance method, and the fixed-effect model were calculated. The Meta-analysis was evaluated using the statistical software Stata/MP v.16 (The fastest version of Stata). Results: A total of 186 potentially relevant titles and abstracts were found during the electronic and manual search. Finally, the inclusion criteria required for this systematic review were met by a total of seven publications. The mean difference of molar mesiodistal movement among seven studies and heterogeneity was -0.53 mm (MD, -0.53 95 % CI -0.69, -0.38. P= 0.00) (I2 = 96.52 %). This result showed maximum reinforcement in miniscrews with fewer mesial movements. Conclusion: The result of the current systematic review and meta-analysis shows that miniscrews in patients with class II and I malocclusion help maintain better anchorage preservation than traditional anchorage devices

Treatment of Class II division I malocclusion having severe crowding, proclination with noncomplaint fixed functional appliance therapy, and frictionless mechanics

Our Objective was to treat a patient having proclined, protruded teeth along with a Class II Skeletal malocclusion. 0.022 × 0.028 inch MBT Brackets were placed, and leveling alignment was commenced. Individual canine retraction was carried out in both arches, followed by retraction of the incisors in the upper arch with a Burrstone's T Loop. E2Z Forsus fatigue resistance appliance was given for the correction of Class II malocclusion. Proclination, protrusion, and crowding were corrected along with Class II Skeletal base. Individual canine retraction along with frictionless mechanics and noncompliant functional correction has sufficient potential to prevent anchor loss and correct a Class II skeletal base.

Fracture Resistance of Teeth Restored with Bulk-Fill and Fiber-Reinforced Composites in Class II Cavities / Resistencia a la fractura de dientes restaurados con resinas de relleno y resinas reforzadas con fibra en cavidades clase II

ABSTRACT: This study aimed to evaluate the fracture resistance of teeth restored with conventional, bulk-fill, and fiber-reinforced composite materials regarding intact teeth. Standard cavities were prepared on 70 sound third molar teeth. The teeth were randomly divided into six groups: intact teeth, conventional Bis-GMA based composite, fiber-reinforced composite, Bis-GMA based bulk-fill composite, ormocer based bulk-fill composite, glass containing resin-based bulk-fill composite. The data was obtained by a Universal Testing Machine and analyzed statistically. Fracture resistance of the teeth restored with conventional composite was significantly lower than the other groups (p0.05). The obtained data showed that restoring teeth with bulk-fill and fiber-reinforced composites could be recommended in Class II cavities.

RESUMEN: El objetivo del presente estudio fue evaluar la resistencia a la fractura de los dientes restaurados con materiales compuestos convencionales, de relleno y reforzados con fibras, en relación con los dientes intactos. Se prepararon cavidades estándar en 70 dientes de terceros molares sanos. Los dientes se dividieron al azar en seis grupos: dientes intactos, compuesto convencional basado en Bis-GMA, compuesto reforzado con fibra, compuesto de relleno a base de Bis-GMA, compuesto de relleno a base de ormocer, compuesto de relleno a base de vidrio que contiene resina. Los resultados fueron obtenidos utilizando una máquina universal de pruebas y analizados estadísticamente. La resistencia a la fractura de los dientes restaurados con el composite convencional fue significativamente menor que la de los otros grupos (p0,05). Los datos obtenidos mostraron que la restauración de dientes con composites de relleno y reforzados con fibra podría ser recomendada en cavidades de Clase II.

Estabilidad del tratamiento ortodóncico-quirúrgico de avance mandibular mediante osteotomía sagital bilateral de rama mandibular en pacientes clase II. Revisión narrativa / Stability of the orthodontic-surgical treatment of mandibular advancement through bilateral sagittal split osteotomy in class II patients. Narrative review

RESUMEN: Introducción: La anomalía esqueletal clase II posee un 16 a 22,5% de prevalencia mundial. Cuando estos pacientes se someten al avance mandibular mediante osteotomía sagital de rama mandibular pueden presentar un grado de inestabilidad postoperatoria evidenciándose como recidiva de éste. Objetivo: Describir la estabilidad del avance mandibular mediante osteotomía sagital bilateral de rama mandibular en pacientes clase II esqueletal. Material y método: Se realizó una búsqueda electrónica en las bases de datos PubMed, EBSCO, The Cochrane Library, Tripdatabase y Scopus mediante las palabras clave "mandibular stability", "skeletal stability", "mandibular advancement", "sagittal split osteotomy", "sagittal split ramus osteotomy", "class II", "class III" y "distraction osteogenesis", relacionadas entre sí con los términos booleanos AND, OR y NOT. También se incluyeron los términos MeSH "mandibular advancement" y "Sagittal Split Ramus Osteotomy". Paralelamente se realizó una búsqueda manual en las revistas AJODO, BJOMS, JOMS y EJO. Resultados y discusión: Se seleccionaron 29 artículos: 24 estudios observacionales analíticos, 2 revisiones sistemáticas y 3 ensayos clínicos aleatorizados. El avance mandibular mediante osteotomía sagital de rama mandibular es estable. No obstante, se debe tener en cuenta la existencia de múltiples factores pre e intraquirúrgicos que podrían generar recidiva del tratamiento.

ABSTRACT: Introduction: The class II skeletal anomaly has a 16-22,5% prevalence worldwide. When class II patients undergo mandibular advancement through Bilateral Sagittal Split Osteotomy (BSSO), they can present a postoperative instability, evidenced as a relapse. Objective: To describe the stability of mandibular advancement through BSSO in skeletal class II patients. Materials and method: An electronic search was performed in the databases PubMed, EBSCO, The Cochrane Library, Tripdatabase and Scopus using the keywords "mandibular stability", "skeletal stability", "mandibular advancement", "sagittal split osteotomy", "sagittal split ramus osteotomy", "class II", "class III" and "distraction osteogenesis", related to each other with the Boolean terms AND, OR and NOT. Also "mandibular advancement" and "Sagittal Split Ramus Osteotomy" MeSH terms were included. In parallel, a manual search in the journals AJODO, BJOMS, JOMS and EJO was performed. Results and discussion: 29 articles were selected: 24 analytic observational studies, 2 systematic reviews and 3 randomized clinical trials. Mandibular advancement through BSSO is stable. However, multiple pre and intraoperative factors that could cause a treatment relapse must be taken into account.

Esfuerzos generados en la ATM en maloclusión clase II, tratada con exodoncias de premolares y ortodoncia: análisis mediante el método de elementos finitos / Strain generated in the TMJ with class II malocclusions, treated with extraction of premolars and orthodontics: analysis with the finite element method

RESUMEN Introducción: la exodoncia de premolares es una alternativa para el tratamiento de la maloclusión clase II. Un cambio en la biomecánica puede generar alteraciones en la Articulación Temporomandibular (ATM) lo que produce mayor desgaste dental y aparición de patologías articulares. El objetivo fue analizar mediante el método de elementos finitos la concentración de esfuerzos en la ATM, en maloclusión clase II, tratados con exodoncia de premolares y Ortodoncia. Métodos: dos modelos de simulación en 3D cada uno con estructuras óseas de los 2 maxilares, dentición completa y disco en la ATM. Uno corresponde al paciente sin recidiva (SR) tratado con exodoncia de primeros premolares y ortodoncia, donde se mantiene la estabilidad dental clase I. El otro modelo con recidiva (CR) tratada con exodoncia de primeros premolares y ortodoncia, aumento de overjet y overbite y clase II canina; la carga se aplicó sobre la rama mandibular. Resultados: con una carga de 900N los esfuerzos se triplicaron en todas las estructuras de los dos modelos al ser comparados con una carga de 300N; sin embargo, se dieron diferencias considerables en el modelo CR entre las cavidades glenoideas, a 300N de 19.9 MPa y a 900N de 59.3 MPa. La mayor concentración del disco se da en la parte lateral. Conclusiones: dada la asimetría en las estructuras de la ATM, los esfuerzos y la concentración de tensiones difieren entre el lado derecho e izquierdo en los dos modelos.

Abstract Introduction: premolar extraction is an alternative for the treatment of class II malocclusion. A change in biomechanics can generate alterations in the Temporomandibular Joint (TMJ), which produces greater dental wear and the appearance of joint dysfunctions. The objective was to assess the effort concentration in the TMJ by means of finite element analysis in class II malocclusions treated with premolar extraction and orthodontics. Method: two 3D simulation models each with bone structures of the 2 jaws, complete dentition and disc in the TMJ. One corresponds to the patient without recurrence (WR) treated with extraction of first premolars and orthodontics, where class I dental stability is maintained. The other model with recurrence (R) treated with extraction of first premolars and orthodontics, increased overjet and overbite and canine class II; the load was applied to the mandibular ramus. Results: loads of 900N triplicated on all structures compared to 300N in both models. However, there were considerable differences between the left and right glenoid cavities in the WR model, at 300N of 19.9 MPa and 900N at 59.3 MPa. Most tensions of the disc occur in the lateral part. Conclusions: due to the asymmetry in the TMJ structures, the stresses and stress concentration differ between the right and left sides in the two models.