Cone-beam computed tomography-based analysis of maxillary sinus pneumatization extended into the alveolar process in different age groups.

OBJECTIVE: This study aimed to measure the amount of maxillary sinus pneumatization (MSP) extended into alveolar processes in different age groups via cone-beam computed tomography (CBCT) and its association with age. METHODS: The data of 293 adult patients (533 maxillary sinuses) who underwent CBCT at our hospital from January 2020 to October 2020 were analyzed and divided into the following age groups: group I (18-34 years old, youth group), group II (35-59 years old, middle-aged group) and group III (≥ 60 years old, elderly group). The distance between the lowest point of the maxillary sinus floor and nasal cavity floor in the central area of the maxillary posterior teeth was measured and recorded as the amount of MSP. Further, according to the positional relation between the maxillary posterior teeth and maxillary sinus floor, MSP was divided into type I (normal pneumatization) and type II (extensive pneumatization). The distribution of pneumatization types and degree and change of pneumatization for the different age groups were also analyzed. P < 0.05 was used as the threshold for statistical significance. RESULTS: The amount of MSP of group I [(3.75 ± 3.77) mm] was significantly higher than that of group II [(2.30 ± 4.48) mm] and group III [(2.09 ± 4.70) mm], but there was no significant difference between group II and group III. We also found that the amount decreased gradually with increasing age (rs = - 0.2), with the youth group showing a higher prevalence of extensive pneumatization (youth vs. middle-age vs. elderly: 66.44% vs. 36.81% vs. 22.28%, respectively). There was no statistically significant difference in the amount of MSP between males and females and between left and right maxillary sinus in each group (P > 0.05). CONCLUSION: The amount of MSP was significantly higher in the 18-34 years old group compared to older age groups, showed a decreasing trend with age and was not associated with sex and maxillary sinus sides.

Well-Aligned TiO2 Nanotube Arrays with Ag Nanoparticles for Highly Efficient Detection of Fe3+ Ion.

Nowadays, determination of the iron ions with high sensitivity and selectivity with novel methods becomes a matter of urgency for monitoring healthy body and environment. In this paper, for the first time, we present a set of high-performance TiO2 nanotube arrays which are quite sensitive to iron ions. Firstly, the anodic oxidation method was adopted to prepare ordered TiO2 nanotube arrays, followed by functionalized Ag nanoparticle deposition with the enhancement ability in iron ion sensing. Besides, the spectrum of the TiO2 nanotube with/without the Ag nanoparticles was analyzed with an X-ray photoelectron spectrometer, which shows that Ag nanoparticles can effectively reduce the recombination rate of electrons and holes, and increase the conductivity and the charge transfer rate of the electrodes. Further, when functionalized Ag nanoparticles on well-ordered TiO2 nanotube arrays were used, iron ion sensing performed with the anodic stripping voltammetry method was investigated to validate the great potential of TiO2 nanotube arrays with a sensitivity of approximately 30 µA/ug/L in becoming Fe3+ sensors. This method creates new possibilities for developing sensors for monitoring of Fe3+ in biological samples without any sample pretreatment procedure.

Preparation of Well-Aligned TiO2 Nanotubes with High Length-Diameter Aspect Ratio by Anodic Oxidation Method.

This paper focused on the influence of various oxidation parameters such as electrolyte composition, reaction time, calcination temperature and current change on the morphology and structure of TiO2 nanotube arrays. It was found that ammonium fluoride with a high viscosity reduced the diffusion rate of fluoride ions and significantly increased the length of TiO2 nanotubes, creating nanotubes with ordered arrays and uniform diameters. Meanwhile, the time of anodic oxidation determined the length of TiO2 nanotube arrays. Well-aligned nanotube arrays could be obtained after 0.5-2.5 h of oxidation. In addition, when the oxidation temperature was about 30 °C, the TiO2 nanotube arrays achieved the optimal uniformity and the maximum length-diameter aspect ratio. The morphology and quality of the TiO2 nanotubes fabricated were estimated through current as a function of reaction time. Consequently, formation mechanism of TiO2 nanotube arrays was investigated undergoing three major periods. The findings of this study can shed some light on the optimal conditions for preparing well-aligned TiO2 nanotube arrays with high length-diameter aspect ratio.