RESUMEN
OBJECTIVES: The aim of this research was to develop a sensor of approximation by reflectance for guided surgery with dental implants without flap detachment, and verify the effectiveness of this system. MATERIALS AND METHODS: Ten models of total edentulous arches were divided into two groups. Two implants of 3.5 × 11.5 mm (NeoDent) were inserted in each model; in Group 1 (G1), a stereolithographic guide NeoGuide system was used. In Group 2 (G2), the experimental approximation sensor was used for the insertion of the implants. The evaluation of the results was performed by overlapping the virtual planning images with the tomographies of the models of the implants inserted. RESULTS: There were no statistically significant differences between the guide and the sensor groups. The averages and standard deviations observed at the angulation of the guide was 4.15 (2.65 degrees) and 5.48 (2.85 degrees) at the sensor. The linear deviations at the cervical level were 0.002 (1.37) and 0.11 (1.47) mm and at the apical level 0.19 (1.28) and 0.21 (1.42) mm, respectively. CONCLUSIONS: The use of a guide is important for the stabilization of the drills; the greatest challenge is to control the apical position of the implants, especially in highly reabsorbed edges. The experimental sensor can become an auxiliary tool to the stereolithographic guides; however, several difficulties must still be overcome to recommend the use of a sensor.
RESUMEN
The chemical composition of biomaterials can drive their biological responses; therefore, this in vitro study aimed to evaluate the proteomic profile of the salivary pellicle formed on titanium (Ti) alloys containing niobium (Nb) and zirconium (Zr). The experimental groups consisted of Ti35NbxZr (x = 5 and 10 wt%) alloys, and commercially pure titanium (cpTi); titanium aluminium vanadium (Ti6Al4V) alloys were used as controls. The physical and chemical characteristics of the Ti materials were analysed. The proteomic profile was evaluated by liquid chromatography coupled with tandem mass spectrometry. Bacterial adhesion (2 h) of mixed species (Streptococcus sanguinis and Actinomyces naeslundii) was investigated as colony-forming units (n = 6). This paper reports the finding that salivary pellicle composition can be modulated by the composition of the Ti material. The Ti35NbxZr group showed a significant ability to adsorb proteins from saliva, which can favour interactions with cells and compatibility with the body.
Asunto(s)
Aleaciones/química , Película Dental/química , Niobio/química , Proteoma/análisis , Proteínas y Péptidos Salivales/análisis , Titanio/química , Circonio/química , Adsorción , Adhesión Bacteriana , Materiales Biocompatibles/química , ProteómicaRESUMEN
OBJECTIVE: The aim of this study was to evaluate the reliability of different dynamometric variables of the pelvic floor muscles (PFM) in healthy women during different periods of menstrual cycle. MATERIALS AND METHODS: Vaginal dynamometric equipment was developed by the authors and its reproducibility was tested. The PFM contractions of 20 healthy women were collected by two independent examiners over three consecutive weeks, always on the same day, with a seven-day interval between readings, starting from the first day after the end of the menstrual period. For the measurements, the branch of the dynamometer was positioned first on the sagittal plane and then on the frontal plane. Baseline, peak time, maximum PFM strength, impulse contraction, and average contraction force were calculated. Reproducibility was tested using the intra-class correlation coefficient (ICC) and standard error of measurement. Repeated-measures ANOVA was used to compare the data from different days. RESULTS: For intra-day and inter-day reliability between examiners, all the parameters collected on the sagittal plane presented good and excellent reproducibility (ICC2,1 = 0.60 to 0.98), whereas reproducibility on the frontal plane was respectively poor and excellent (ICC2,1 = 0.23 to 0.97). The ANOVA revealed significant differences between sessions only for the impulse of contraction for the sagittal (P = 0.005) and frontal (P = 0.03) planes. CONCLUSIONS: Time and contraction force parameters of the PFM are not influenced by hormonal alterations that occur during the menstrual cycle. The impulse of contraction was the only variable to demonstrate a significant difference between the first and second week of the data collection protocol. The baseline, maximum strength value, impulse of contraction, and average contraction force variables presented good to excellent reproducibility and can be safely used as a method of PFM evaluation.