RESUMEN
This observational, cross-sectional study with retrospective collection was aimed to evaluate the prevalence of morphological changes in mandibular condyles in individuals with class II malocclusion, classified according to different vertical growth patterns (brachyfacial, mesofacial, and dolichofacial), through cone beam computed tomography (CBCT). Seventy CBCT images (140 mandibular condyles) were selected from individuals without orthodontic treatment, of both sexes, aged between 25 and 50 years. No statistically significant differences were found between facial patterns; however, there was a higher relative prevalence of bone changes in dolichofacial individuals with flattening (62%), sclerosis (44%), and subchondral bone cyst (20%). Erosion and osteophytes prevailed in mesofacial (39%), and brachyfacial individuals (32%), respectively. Thus, there was no statistically significant difference in the prevalence of degenerative changes between the vertical skeletal patterns. Flattening was the most prevalent change, whereas subchondral bone cyst was the least prevalent among the three groups studied. The observational design of this study makes it possible to analyze image banks to verify the correlation of morphological changes in the temporomandibular joint in different facial patterns in patients with class II malocclusion. A limitation of the study is that clinical characteristics were not evaluated.
Asunto(s)
Tomografía Computarizada de Haz Cónico , Maloclusión Clase II de Angle , Cóndilo Mandibular , Humanos , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/patología , Maloclusión Clase II de Angle/epidemiología , Femenino , Masculino , Adulto , Estudios Transversales , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/patología , Estudios Retrospectivos , Persona de Mediana Edad , Prevalencia , Valores de Referencia , Articulación Temporomandibular/diagnóstico por imagen , Articulación Temporomandibular/patologíaRESUMEN
Abstract This observational, cross-sectional study with retrospective collection was aimed to evaluate the prevalence of morphological changes in mandibular condyles in individuals with class II malocclusion, classified according to different vertical growth patterns (brachyfacial, mesofacial, and dolichofacial), through cone beam computed tomography (CBCT). Seventy CBCT images (140 mandibular condyles) were selected from individuals without orthodontic treatment, of both sexes, aged between 25 and 50 years. No statistically significant differences were found between facial patterns; however, there was a higher relative prevalence of bone changes in dolichofacial individuals with flattening (62%), sclerosis (44%), and subchondral bone cyst (20%). Erosion and osteophytes prevailed in mesofacial (39%), and brachyfacial individuals (32%), respectively. Thus, there was no statistically significant difference in the prevalence of degenerative changes between the vertical skeletal patterns. Flattening was the most prevalent change, whereas subchondral bone cyst was the least prevalent among the three groups studied. The observational design of this study makes it possible to analyze image banks to verify the correlation of morphological changes in the temporomandibular joint in different facial patterns in patients with class II malocclusion. A limitation of the study is that clinical characteristics were not evaluated.
RESUMEN
Objective: in this study, biofilm formation by Candida albicans in fixed orthodontic appliances was evaluated. Material and Methods: a total of 300 conventional metal brackets (MC), ceramic (CB), self-ligation (SLB), nickel-titanium (NiTi), and nickel-chromium (NiCr) wires, and ligatures types were organized into thirty groups (n=10). To induce biofilm formation, brackets, wires, and ligatures were joined, sterilized, placed in 24-well plates, contaminated with standardized suspensions of C. albicans (107 cells/mL), and incubated at 37 °C for 48 h with shaking. The biofilms formed were detached using an ultrasonic homogenizer, and suspensions were serially diluted and plated on Sabouraud dextrose agar to determine colony-forming units per mL. Scanning electron microscopy was performed before and after the biofilm formation. Results: lower amount of biofilm formation was observed in the MC group than in the CB and SLB groups (p<0.0001). SLB and CB showed similar biofilm formation rates (p=0.855). In general, the cross-sectional wires .018"x.025" showed higher biofilm formation when associated with the three types of brackets. When brackets, wires, and ligatures were associated, the sets with NiCr wires and SSL ligatures with MC brackets (p=0.0008) and CB (p=0.0003) showed higher biofilm formation. Conclusion: thus, brackets of MC with NiTi and NiCr wires showed lower biofilm formation, regardless of the ligature and cross-sectional or gauge of the wire and, MC and CB brackets with NiCr wires and SSL ligatures were more likely to accumulate biofilms (AU)
Objetivo: neste estudo, a formação de biofilme por Candida albicans em aparelhos ortodônticos fixos foi avaliada. Material e Métodos: um total de 300 bráquetes metálicos convencionais (MC), cerâmicos (CB), autoligados (SLB), com fios de níquel-titânio (NiTi) e níquel-cromo (NiCr) e tipos de ligaduras foram organizados em trinta grupos (n=10). Bráquetes, fios e ligaduras foram unidos, esterilizados, colocados em placas de 24 poços, contaminados com suspensões padronizadas de C. albicans (107 células/mL) e incubados a 37°C por 48 h para a formação de biofilmes. Os biofilmes formados foram rompidos por meio de um homogeneizador ultrassônico e suspensões foram diluídas e semeadas em ágar Sabouraud-dextrose para determinar as unidades formadoras de colônias por mL. A microscopia eletrônica de varredura foi realizada antes e após a formação do biofilme. Resultados: foi observada menor formação de biofilme no grupo MC em comparação aos grupos CB e SLB (p<0,0001). A formação de biofilme foi semelhante nos grupos SLB e CB (p=0,855). Em geral, os fios de seção transversal .018"x.025" apresentaram maior formação de biofilme quando associados aos três tipos de bráquetes. Os conjuntos com fios de NiCr e ligaduras SSL com bráquetes MC (p=0,0008) e CB (p=0,0003) apresentaram maior formação de biofilme. Conclusão: bráquetes MC com fios de NiTi e NiCr apresentaram menor formação de biofilme, independente da ligadura e secção transversal ou bitola do fio e, braquetes MC e CB com fios de NiCr e ligaduras SSL foram mais propensos a acumular biofilmes.(AU)