nitinol and Gingivitis

Without a phase of retention after successful orthodontic treatment, teeth tend to 'relapse', that is, to return to their initial position. Retention is achieved by fitting fixed or removable retainers to provide stability to the teeth while avoiding damage to teeth and gums. Removable retainers can be worn full- or part-time. Retainers vary in shape, material, and the way they are made. Adjunctive procedures are sometimes used to try to improve retention, for example, reshaping teeth where they contact ('interproximal reduction'), or cutting fibres around teeth ('percision'). This review is an update of one originally published in 2004 and last updated in 2016.. To evaluate the effects of different retainers and retention strategies used to stabilise tooth position after orthodontic braces.. An information specialist searched Cochrane Oral Health Trials Register, CENTRAL, MEDLINE, Embase and OpenGrey up to 27 April 2022 and used additional search methods to identify published, unpublished and ongoing studies.  SELECTION CRITERIA: Randomised controlled trials (RCTs) involving children and adults who had retainers fitted or adjunctive procedures undertaken to prevent relapse following orthodontic treatment with braces. We excluded studies with aligners.. Two review authors independently screened eligible studies, assessed risk of bias and extracted data. Outcomes were stability or relapse of tooth position, retainer failure (i.e. broken, detached, worn out, ill-fitting or lost), adverse effects on teeth and gums (i.e. plaque, gingival and bleeding indices), and participant satisfaction. We calculated mean differences (MD) for continuous data, risk ratios (RR) or risk differences (RD) for dichotomous data, and hazard ratios (HR) for survival data, all with 95% confidence intervals (CI). We conducted meta-analyses when similar studies reported outcomes at the same time point; otherwise results were reported as mean ranges. We prioritised reporting of Little's Irregularity Index (crookedness of anterior teeth) to measure relapse, judging the minimum important difference to be 1 mm.. We included 47 studies, with 4377 participants. The studies evaluated: removable versus fixed retainers (8 studies); different types of fixed retainers (22 studies) or bonding materials (3 studies); and different types of removable retainers (16 studies). Four studies evaluated more than one comparison. We judged 28 studies to have high risk of bias, 11 to have low risk, and eight studies as unclear.  We focused on 12-month follow-up.  The evidence is low or very low certainty. Most comparisons and outcomes were evaluated in only one study at high risk of bias, and most studies measured outcomes after less than a year. Removable versus fixed retainers Removable (part-time) versus fixed   One study reported that participants wearing clear plastic retainers part-time in the lower arch had more relapse than participants with multistrand fixed retainers, but the amount was not clinically significant (Little's Irregularity Index (LII) MD 0.92 mm, 95% CI 0.23 to 1.61; 56 participants). Removable retainers were more likely to cause discomfort (RR 12.22; 95% CI 1.69 to 88.52; 57 participants), but were associated with less retainer failure (RR 0.44, 95% CI 0.20 to 0.98; 57 participants) and better periodontal health (Gingival Index (GI) MD -0.34, 95% CI -0.66 to -0.02; 59 participants). Removable (full-time) versus fixed   One study reported that removable clear plastic retainers worn full-time in the lower arch did not provide any clinically significant benefit for tooth stability over fixed retainers (LII MD 0.60 mm, 95% CI 0.17 to 1.03; 84 participants). Participants with clear plastic retainers had better periodontal health (gingival bleeding RR 0.53, 95% CI 0.31 to 0.88; 84 participants), but higher risk of retainer failure (RR 3.42, 95% CI 1.38 to 8.47; 77 participants). The study found no difference between retainers for caries.  Different types of fixed retainers Computer-aided design/computer-aided manufacturing (CAD/CAM) nitinol versus conventional/analogue multistrand One study reported that CAD/CAM nitinol fixed retainers were better for tooth stability, but the difference was not clinically significant (LII MD -0.46 mm, 95% CI -0.72 to -0.21; 66 participants). There was no evidence of a difference between retainers for periodontal health (GI MD 0.00, 95% CI -0.16 to 0.16; 2 studies, 107 participants), or retainer survival (RR 1.29, 95% CI 0.67 to 2.49; 1 study, 41 participants). Fibre-reinforced composite versus conventional multistrand/spiral wire . The evidence is low to very low certainty, so we cannot draw firm conclusions about any one approach to retention over another. More high-quality studies are needed that measure tooth stability over at least two years, and measure how long retainers last, patient satisfaction and negative side effects from wearing retainers, such as tooth decay and gum disease.. Sin una fase de retención tras un tratamiento de ortodoncia exitoso, los dientes tienden a "recaer", es decir, a volver a su posición inicial. La retención se consigue colocando retenedores fijos o removibles para proporcionar estabilidad a los dientes y evitar al mismo tiempo daños en dientes y encías. Los retenedores removibles pueden llevarse a tiempo completo o parcial. Los retenedores varían en la forma, el material y el modo de fabricación. A veces se utilizan procedimientos complementarios para intentar mejorar la retención, por ejemplo, remodelando los dientes en la zona de contacto ("reducción interproximal") o cortando fibras alrededor de los dientes ("pericisión"). Esta revisión es una actualización de una publicada originalmente en 2004 y actualizada por última vez en 2016.. Evaluar los efectos de los diferentes retenedores y estrategias de retención utilizados para estabilizar la posición de los dientes después del tratamiento con aparatos de ortodoncia. MÉTODOS DE BÚSQUEDA: Un documentalista realizó búsquedas en el Registro de ensayos del Grupo Cochrane de Salud oral (Cochrane Oral Health), en CENTRAL, MEDLINE, Embase y OpenGrey hasta el 27 de abril de 2022 y utilizó métodos de búsqueda adicionales para identificar estudios publicados, no publicados y en curso. CRITERIOS DE SELECCIÓN: Ensayos controlados aleatorizados (ECA) con niños y adultos a los que se les colocaron retenedores o se les realizaron procedimientos complementarios para prevenir la recaída tras el tratamiento con aparatos de ortodoncia. Se excluyeron los estudios con alineadores. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Dos autores de la revisión realizaron de forma independiente la revisión de los estudios elegibles, evaluaron el riesgo de sesgo y extrajeron los datos. Los desenlaces fueron la estabilidad o recaída de la posición dental, el fracaso del retenedor (es decir, roto, desprendido, desgastado, mal ajustado o perdido), los efectos adversos en dientes y encías (es decir, índices de placa, gingivales y de sangrado) y la satisfacción de los participantes. Se calcularon las diferencias de medias (DM) para los datos continuos, las razones de riesgos (RR) o las diferencias de riesgos (DR) para los datos dicotómicos, y los cociente de riesgos instantáneos (CRI) para los datos de supervivencia, todos ellos con intervalos de confianza (IC) del 95%. Se realizaron metanálisis cuando estudios similares informaron desenlaces en el mismo punto temporal; de lo contrario, los resultados se informaron como rangos medios. Se dio prioridad a la notificación del Little's Irregularity Index (torcedura de los dientes anteriores) para medir la recaída, considerando que la diferencia mínima importante era de 1 mm.. Se incluyeron 47 estudios con 4377 participantes. Los estudios evaluaron: retenedores removibles versus fijos (ocho estudios); diferentes tipos de retenedores fijos (22 estudios) o materiales adhesivos (tres estudios); y diferentes tipos de retenedores removibles (16 estudios). Cuatro estudios evaluaron más de una comparación. Se consideró que 28 estudios tenían un alto riesgo de sesgo, 11 un riesgo bajo y en ocho estudios fue incierto. El centro de atención de esta revisión fue el seguimiento a los 12 meses. La evidencia es de certeza baja a muy baja. La mayoría de las comparaciones y los desenlaces se evaluaron en un solo estudio con alto riesgo de sesgo, y la mayoría de los estudios midieron los desenlaces después de menos de un año. Retenedores removibles versus fijos Removible (a tiempo parcial) versus fijo Un estudio informó que los participantes que llevaban retenedores de plástico transparente a tiempo parcial en la arcada inferior presentaron más recaídas que los participantes con retenedores fijos de múltiples barras, pero la cantidad no fue clínicamente significativa (Little's Irregularity Index [IIL] DM 0,92 mm; IC del 95%: 0,23 a 1,61; 56 participantes). Los retenedores removibles tuvieron más probabilidades de causar molestias (RR 12,22; IC del 95%: 1,69 a 88,52; 57 participantes), pero se asociaron con menos fracaso del retenedor (RR 0,44; IC del 95%: 0,20 a 0,98; 57 participantes) y mejor salud periodontal (Gingival Index [IG] DM ‐0,34; IC del 95%: ‐0,66 a ‐0,02; 59 participantes). Removible (a tiempo completo) versus fijo Un estudio informó que los retenedores removibles de plástico transparente utilizados a tiempo completo en la arcada inferior no proporcionaron efectos beneficiosos clínicamente significativos en la estabilidad dental en comparación con los retenedores fijos (LII DM 0,60 mm; IC del 95%: 0,17 a 1,03; 84 participantes). Los participantes con retenedores de plástico transparente tenían mejor salud periodontal (sangrado gingival RR 0,53; IC del 95%: 0,31 a 0,88; 84 participantes), pero mayor riesgo de fracaso del retenedor (RR 3,42; IC del 95%: 1,38 a 8,47; 77 participantes). El estudio no encontró diferencias entre los retenedores en las caries. Diferentes tipos de retenedores fijos De nitinol con diseño asistido por ordenador/fabricación asistida por ordenador (DAO/FAO) versus de múltiples barras convencional/analógico Un estudio informó que los retenedores fijos de nitinol con DAO/FAO fueron mejores para la estabilidad de. La evidencia es de certeza baja a muy baja, por lo que no fue posible establecer conclusiones firmes sobre un método de retención en detrimento de otro. Se necesitan más estudios de alta calidad que midan la estabilidad de los dientes durante al menos dos años, así como la duración de los retenedores, la satisfacción de los pacientes y los efectos secundarios negativos del uso de retenedores, como caries y enfermedades de las encías.

Topics: Adult; Child; Dental Care; Drug-Related Side Effects and Adverse Reactions; Gingivitis; Humans; Orthodontic Brackets; Periodontal Diseases

This study provides a vital insight in assessing the clinical and biochemical changes in interleukin (IL)-1β levels in peri-miniscrew crevicular fluid (PMCF) during the course of orthodontic tooth movement.. The study comprised the analysis of IL-1β in peri-miniscrew crevicular fluid obtained from crevices around the miniscrews inserted in 11 patients (eight females and three males, mean age 17.3 ± 4.64 years) with all first premolar extraction and maximum anchorage requirement using miniscrew-supported anchorage. Miniscrews were loaded at 3 weeks after placement by 200-g nitinol closed coil springs of 9-mm length for en masse retraction. Peri-miniscrew crevicular fluid was collected at miniscrew placement (T1), at 3 weeks (T2/baseline) and on loading at 0 (T3) and 1 day (T4), 21 (T5), 72 (T6), 120 (T7), 180 (T8) and 300 (T9) days. IL-1β levels were estimated by enzyme-linked immunosorbent assay (ELISA). Peri-miniscrew tissue was examined for signs of inflammation, and also, miniscrew mobility was assessed with Periotest and handles of two mouth mirrors.. IL-1β levels in all miniscrews were significantly higher at T1 and peaked again at T4 showing a bimodal peak. However, there was a gradual and statistically significant decrease in IL-1β till T5, while further changes till the end of the study were statistically not significant.. The changing levels of IL-1β levels in PMCF over a duration of 300 days are suggestive of the underlying inflammatory process. IL-1β levels in PMCF show a significant rise during miniscrew insertion and on immediate loading. The trend of gradually reducing IL-1β levels around the miniscrew over the period after loading towards baseline is suggestive of adaptive bone response to stimulus.

Topics: Adaptation, Physiological; Adolescent; Alloys; Bone Screws; Dental Alloys; Female; Follow-Up Studies; Gingival Crevicular Fluid; Gingivitis; Humans; Interleukin-1beta; Male; Mucositis; Orthodontic Anchorage Procedures; Orthodontic Wires; Osseointegration; Peri-Implantitis; Tooth Movement Techniques

To determine the influence of chromium and nickel concentrations in saliva and their effects on gingival tissues during orthodontic treatment.. Twenty orthodontic patients (10 males and 10 females), 17 to 20 years of age, were treated with fixed orthodontic appliances in the maxillary arch. Using atomic absorption spectrophotometer, the concentration of both metals was recorded during pretreatment, at 3 and 12 months into treatment, and 1 month after debonding. The depth of gingival crevice was recorded as well.. After 3 months, 20% of females and 10% of males in this study showed allergic reaction in a form of gingivitis. This had disappeared by 1 month after appliance removal.. While allergy to either nickel or chromium is not a serious medical problem, oral hygiene measures in at-risk patients should be optimal, with use of fluoride-free toothpaste and mouthrinse.

Topics: Adolescent; Adult; Alloys; Chromium; Dental Alloys; Dental Debonding; Female; Follow-Up Studies; Gingiva; Gingivitis; Humans; Hypersensitivity; Longitudinal Studies; Male; Nickel; Orthodontic Appliances; Periodontal Index; Saliva; Spectrophotometry, Atomic; Stainless Steel