Partially stabilized zirconia (PSZ) exhibits excellent physical, mechanical, electrical, chemical, thermal, and bioactive properties. Therefore, it is frequently used as a material for thermal barrier coatings, refractories, oxygen-permeating membranes, dental and bone implants. In this study, magnesia-partially stabilized zirconia nanoparticles were successfully prepared from zirconium silicates and MgSO4 assisted with PEG-6000 via a facile templating method. The MgO concentration was varied from 1%–10% in wt% of ZrO2. Zirconium silicates were initially converted to Zr-precursor solution, exhibiting pH 3. Then, the appropriate amount of the Mg-precursor was mixed with the proper amount of the Zr-precursor solution. A 10%(w/v) PEG-6000 solution was added into the PSZ precursor solution at a ratio of the precursor-to-PEG volumes of about 15:1 under stirring and heating, resulting in a very fine white gel. The gel was filtered, dried, and then calcined at elevated temperatures of 600, 800, and 1000 °C. The characteristics of the final product were then evaluated. According to the experimental results, the MgO concentration influences the ZrO2 phase transformation at elevated calcination temperatures. In this study, the lower the MgO dopant concentration added into ZrO2, the more stable the t- ZrO2 phase in PSZ samples at high temperatures. However, the MgO presence is detected as periclase in all samples with a very low peak intensity at elevated calcination temperatures. The obtained PSZ samples consist of nanoparticles and high agglomeration, some of particles exhibit elongated and rod-like shapes. The PEG existence during the PSZ preparation has restrained particle interaction and aggregation of the as-synthesized PSZ samples, leading to PSZ nanoparticles evolution.

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Chronic otitis media (COM) is still highly prevalent in developing countries and often become main cause of deafness and morbid complication. Appropriate management may decrease the morbidity and mortality rate. The aim of the study are to evaluate preoperative and intraoperative finding among COM patients. A descriptive study was conducted at Mohammad Hoesin Hospital Palembang from April 2015 to April 2018. A secondary data was taken from medical records. A total of 252 patients were included in this study with the highest incidence was at 21-30 years old group (29,36 %) with male predominance. The most frequent preoperative assessment were total perforation of tympanic membrane in 104 patients (41.26 %), moderately severe mixed hearing loss in 61 patients (24,2%), and mastoiditis with cholesteatoma in computed tomography (CT) finding in 158 patients (62,69 %). In intraoperative finding, there were 202 patients (80,15%) with cholesteatoma whereas 103 patients (40,87 %) with granulation tissue. Ossicular chain destruction were found in 141 patients (55,95 %). Canal Wall Down Mastoidectomy (CWD) were performed in 190 patients (75,39 %). The prevalence of COM with cholesteatoma at Mohammad Hoesin hospital is still high. Operative management using CWD technique is preferred in cases of COM with cholesteatoma.

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