Digital morphometric analysis of root changes in upper incisors of young patients during eighteen months of orthodontic treatment

ABSTRACT: Orthodontically induced external root resorption is not a well understood phenomenon, and although it has been widely studied in the orthodontic literature, its nature, causes and effects are still controversial. Since there is no clarity about the apical root changes that take place during the orthodontic treatment, the aim of this study was to determine quantitative changes in root morphology during fixed periods of time (0, 6, 12, 18 months) based on a radiographic assessment. Methods: the dependent variables analysed were: area and root length, the independent variables were. treatment time, gender, age, root form, type of wire, diagnosis, oral habits, trauma, extractions, medical history, maxillary expansion and use of elastics. The method used to evaluate and calculate the root changes was the digital morphometric analysis of periapical radiographs. The sample consisted of 26 young patients (14 males- 12 females) between 11-21 years of age that were going to be treated at the Dental School of the University of Antioquia by students of the postgraduate Orthodontic program. Results and conclusions: the results had a statistical significance of 95% and led to the following conclusions: 1) root integrity was affected in the upper incisors of all patients during the 18 months of treatment. 2) The greatest changes occurred during the first six months and were significant after 18 months of treatment. 3) Upper lateral incisors were more susceptible to root resorption than upper central incisors. 4) The conditions that favored root resorption in this sample were: male gender, medical history of respiratory allergies, maxillary expansion prior to orthodontic therapy, orthodontic treatment with extractions of first upper bicuspids, and standard edgewise brackets. 5) These results are applicable to the sample analyzed and should not be extrapolated to the general population, but the information is valid to be considered in future studies with a larger sample.RESUMEN: La reabsorción radicular asociada al tratamiento ortodóncico es un fenómeno, que aunque ha sido bastante debatido en la literatura, su naturaleza, causa y efectos son aún controvertidos. Debido a la discusión que se presenta en la literatura acerca del comportamiento radicular durante el tiempo del tratamiento de ortodoncia, se realizó un estudio de seguimiento radiográfico con el propósito de determinar cuantitativamente los cambios en la anatomía radicular considerando intervalos fijos de tiempo (0, 6, 12, 18 meses). Métodos: el análisis se centró en la evaluación de variables relacionadas con la reabsorción radicular, incluyendo variables dependientes como: área y longitud radicular e independientes como: tiempo de tratamiento, género, edad, forma radicular, tipo de alambre utilizado, diagnóstico, hábitos, trauma, exodoncias, antecedentes médicos, expansión maxilar, uso de elásticos y tipo de brackets. La técnica usada para evaluar los cambios radiculares radiográficos fue la morfometría digital. Se tomó una muestra de 26 pacientes (14 hombres y 12 mujeres) entre los 11 y 21 años, atendidos por estudiantes del posgrado de Odontología Integral del Adolescente y Ortodoncia de la Facultad de Odontología de la Universidad de Antioquia. Resultados y conclusiones: los resultados obtenidos con significancia estadística a un nivel de confianza del 95% permitieron las siguientes conclusiones: 1) Se observaron cambios en la integridad radicular en todos los incisivos superiores durante los 18 meses de tratamiento. 2) Los mayores cambios se presentaron durante los primeros seis meses de tratamiento y fueron significativos a los 18 meses. 3) Los incisivos laterales superiores fueron más susceptibles a la reabsorción radicular que los incisivos centrales superiores. 4) Las condiciones que favorecieron la reabsorción radicular en esta muestra fueron: género masculino, antecedente médico de rinitis, expansión maxilar previa a la terapia ortodóncica, tratamiento ortodóncico con exodoncias de primeros bicúspides superiores y aparatología con prescripción estándar. 5) Los resultados discutidos son aplicables a la muestra estudiada y no se deberán extraplolar a todo el universo, pero la información si es muy valiosa para considerarse en futuros estudios con muestra mayor

Evaluación del efecto del rofecoxib en los cambios dentino-pulpares, el movimiento dental y la inhibición de la reabsorción radicular durante la aplicación de fuerzas ortodóncicas intrusivas

ABSTRACT: Root resorption associated to dental movement is an undesired side effect during orthodontic therapy. The purpose of this study was to identify the changes in the pulp-dentine organ, the degree of external root resorption, and the amount of dental movement in patients under Rofecoxib treatment, during the application of 2 ounce-intrusive orthodontic forces. The sample consisted of 6 subjects (12 teeth) on whom 8 teeth were evaluated as the experimental group (Rofecoxib) and 4 teeth as the control group (placebo). A fixed device (transpalatal bar) was used and a bracket was attached to the middle third of the buccal surface of the first upper premolar. On each segment a TMA wire with intrusive bends was set and activated every 6 weeks. The protocol of drug and placebo intake was determined by taking into account the stabilization of their concentration after regular administration. As part of the treatment, the premolars were extracted and prepared for histological examination. These cuts were dyed with Hematoxilin-Eosin colorants and Masson’s Trichoromic in order to observe them under the light microscope. The histological cuts showed more morphological changes at the odontoblastic layer, with increase in the number of collagen fibers and angiogenesis for the experimental group. In contrast, the control group presented more root damage than the experimental group. The range of dental movement under Rofecoxib was greater than the range under placebo after measuring the degree of dental movement. The rofecoxib showed to be effective in the inhibition of the RRE, compared with a medication placebo in this sample. With the current limitations to the rofecoxib use, one can say that the preferential inhibitors of the COX-2 present a better control that the specific inhibitors of the COX-2 in the dentinopulpar deleterious changes that are presented after the intrusive movement.RESUMEN: La reabsorción radicular asociada al movimiento dental es un efecto indeseado durante la terapia ortodóncica. El propósito de este estudio fue el de identificar los cambios dentinopulpares, el grado de reabsorción radicular externa (RRE) y la cantidad de movimiento dental en pacientes medicados con rofecoxib durante la aplicación de fuerzas ortodóncicas intrusivas de 2 onzas. La muestra la constituyeron 6 sujetos (12 dientes) en quienes se evaluaron 8 dientes para el grupo experimental (rofecoxib) y 4 dientes para el grupo control (placebo). Se utilizó un aparato fijo tipo barra transpalatina y un bracket adherido a tercio medio de la cara vestibular de los primeros bicúspides superiores, en cada segmento se instaló un alambre TMA con dobleces intrusivos que fueron activados cada seis semanas. El protocolo de administración del medicamento y del placebo se planteó teniendo en cuenta la estabilización de su concentración tras su administración en forma regular. Como parte del tratamiento los premolares fueron extraídos y se realizaron los cortes respectivos, se utilizó coloración de hematoxilina-eosina y tricrómica de Masson para observar los cortes al microscopio de luz. En los cortes histológicos se observó en la capa odontoblástica mayores cambios morfológicos, aumento de las fibras colágenas y angiogénesis en el grupo experimental. Se encontró que el grupo control presentó mayor cantidad de lesiones radiculares que el grupo experimental. Al medir la cantidad de movimiento dental, se observó que los rangos de movimiento bajo el rofecoxib fueron mayores que con el placebo. El rofecoxib mostró ser eficaz en la inhibición de la RRE, comparado con un medicamento placebo en esta muestra. Con las actuales limitaciones del uso del rofecoxib, se puede decir que los inhibidores preferenciales de la ciclooxigenasa-2 (COX -2) presentan mejor control que los inhibidores específicos de la COX-2 en los cambios dentinopulpares deletéreos que se presentan luego del movimiento intrusivo

Omecamtiv mecarbil in chronic heart failure with reduced ejection fraction, GALACTIC‐HF: baseline characteristics and comparison with contemporary clinical trials

Aims: The safety and efficacy of the novel selective cardiac myosin activator, omecamtiv mecarbil, in patients with heart failure with reduced ejection fraction (HFrEF) is tested in the Global Approach to Lowering Adverse Cardiac outcomes Through Improving Contractility in Heart Failure (GALACTIC‐HF) trial. Here we describe the baseline characteristics of participants in GALACTIC‐HF and how these compare with other contemporary trials. Methods and Results: Adults with established HFrEF, New York Heart Association functional class (NYHA) ≥ II, EF ≤35%, elevated natriuretic peptides and either current hospitalization for HF or history of hospitalization/ emergency department visit for HF within a year were randomized to either placebo or omecamtiv mecarbil (pharmacokinetic‐guided dosing: 25, 37.5 or 50 mg bid). 8256 patients [male (79%), non‐white (22%), mean age 65 years] were enrolled with a mean EF 27%, ischemic etiology in 54%, NYHA II 53% and III/IV 47%, and median NT‐proBNP 1971 pg/mL. HF therapies at baseline were among the most effectively employed in contemporary HF trials. GALACTIC‐HF randomized patients representative of recent HF registries and trials with substantial numbers of patients also having characteristics understudied in previous trials including more from North America (n = 1386), enrolled as inpatients (n = 2084), systolic blood pressure < 100 mmHg (n = 1127), estimated glomerular filtration rate < 30 mL/min/1.73 m2 (n = 528), and treated with sacubitril‐valsartan at baseline (n = 1594). Conclusions: GALACTIC‐HF enrolled a well‐treated, high‐risk population from both inpatient and outpatient settings, which will provide a definitive evaluation of the efficacy and safety of this novel therapy, as well as informing its potential future implementation

Cardiac myosin activation with omecamtiv mecarbil in systolic heart failure

BACKGROUND The selective cardiac myosin activator omecamtiv mecarbil has been shown to improve cardiac function in patients with heart failure with a reduced ejection fraction. Its effect on cardiovascular outcomes is unknown. METHODS We randomly assigned 8256 patients (inpatients and outpatients) with symptomatic chronic heart failure and an ejection fraction of 35% or less to receive omecamtiv mecarbil (using pharmacokinetic-guided doses of 25 mg, 37.5 mg, or 50 mg twice daily) or placebo, in addition to standard heart-failure therapy. The primary outcome was a composite of a first heart-failure event (hospitalization or urgent visit for heart failure) or death from cardiovascular causes. RESULTS During a median of 21.8 months, a primary-outcome event occurred in 1523 of 4120 patients (37.0%) in the omecamtiv mecarbil group and in 1607 of 4112 patients (39.1%) in the placebo group (hazard ratio, 0.92; 95% confidence interval [CI], 0.86 to 0.99; P = 0.03). A total of 808 patients (19.6%) and 798 patients (19.4%), respectively, died from cardiovascular causes (hazard ratio, 1.01; 95% CI, 0.92 to 1.11). There was no significant difference between groups in the change from baseline on the Kansas City Cardiomyopathy Questionnaire total symptom score. At week 24, the change from baseline for the median N-terminal pro-B-type natriuretic peptide level was 10% lower in the omecamtiv mecarbil group than in the placebo group; the median cardiac troponin I level was 4 ng per liter higher. The frequency of cardiac ischemic and ventricular arrhythmia events was similar in the two groups. CONCLUSIONS Among patients with heart failure and a reduced ejection, those who received omecamtiv mecarbil had a lower incidence of a composite of a heart-failure event or death from cardiovascular causes than those who received placebo. (Funded by Amgen and others; GALACTIC-HF ClinicalTrials.gov number, NCT02929329; EudraCT number, 2016 -002299-28.)