Enhancement of Hydrophilicity of Nano-Pitted TiO2 Surface Using Phosphoric Acid Etching.

Our research group developed a novel nano-pitted (NP) TiO2 surface on grade 2 titanium that showed good mechanical, osteogenic, and antibacterial properties; however, it showed weak hydrophilicity. Our objective was to develop a surface treatment method to enhance the hydrophilicity of the NP TiO2 surface without the destruction of the nano-topography. The effects of dilute and concentrated orthophosphoric (H3PO4) and nitric acids were investigated on wettability using contact angle measurement. Optical profilometry and atomic force microscopy were used for surface roughness measurement. The chemical composition of the TiO2 surface and the oxidation state of Ti was investigated using X-ray photoelectron spectroscopy. The ccH3PO4 treatment significantly increased the wettability of the NP TiO2 surfaces (30°) compared to the untreated control (88°). The quantity of the absorbed phosphorus significantly increased following ccH3PO4 treatment compared to the control and caused the oxidation state of titanium to decrease (Ti4+ → Ti3+). Owing to its simplicity and robustness the presented surface treatment method may be utilized in the industrial-scale manufacturing of titanium implants.

Risk assessment of bisphosphonate-related osteonecrosis of the jaw based on CBCT scans / A biszfoszfonátkezelés állcsontnekrózist eloidézo kockázatának megítélése CBCT-felvételek alapján.

INTRODUCTION: Bisphosphonate-related osteonecrosis of the jaw is a condition that severely affects the quality of life, therefore an early diagnosis is of utmost importance (both from a general and a surgical point of view), alongside with an accurate assessment of the risk of emergence of the disease. AIM: Estimation of the prognosis is not resolved; among several radiological options those used in dentistry seem the most fit for the purpose, with cone-beam computed tomography (CBCT) being superior in this task. Assessment of the risk of BRONJ developed following orally applied bisphosphonate is unemphatic in most case studies - these focus more on the intravenous application carrying a greater risk of BRONJ. METHOD: In contrast with the studies published so far, we performed our measurements on preoperative CBCT scans, thereby directly studying the possibility of risk assessment. Our measurements were conducted through evaluating CBCT scans. We chose the frontal section in the midline of the mental foramen as the representative area. We measured density and thickness of the cortical bone on several given points; the diameter of the mental foramen was also measured. In the first group, we examined patients suffering from osteoporosis who had developed BRONJ following oral bisphosphonate treatment. In the second group, we looked at patients suffering from osteoporosis, who had received oral bisphosphonate therapy for this condition but did not develop BRONJ after oral surgery. As control group, we chose patients suffering from osteoporosis who had not received any of the medications known to cause BRONJ. RESULTS: Based on our results, it is clear that there is no significant difference in the bone density of those patients who developed BRONJ and those who did not, examining the preoperative CBCT scans. CONCLUSIONS: Using CBCT scans (and thereby submitting the patient to radiation exposure) in order to estimate the possibility of BRONJ following oral bisphosphonate treatment for osteoporosis is not recommended. It is important not to expose patients to more radiation than strictly necessary to predict BRONJ following oral bisphosphonate treatment in accordance with the ALARA (as low as reasonably achievable) principle. Orv Hetil. 2020; 161(21): 867-872.

Pravastatin induces NO synthesis by enhancing microsomal arginine uptake in healthy and preeclamptic placentas.

BACKGROUND: Pravastatin, a known inducer of endothelial nitric-oxide synthase (eNOS) was demonstrated in human placenta, however the exact mechanism of it's action is not fully understood. Since placental NO (nitric oxide) synthesis is of primary importance in the regulation of placental blood flow, we aimed to clarify the effects of pravastatin on healthy (n = 6) and preeclamptic (n = 6) placentas (Caucasian participants). METHODS: The eNOS activity of human placental microsomes was determined by the conversion rate of C14 L-arginine into C14 L-citrulline with or without pravastatin and Geldanamycin. Phosphorylation of eNOS (Ser1177) was investigated by Western blot. Microsomal arginine uptake was measured by a rapid filtration method. RESULTS: Pravastatin significantly increased total eNOS activity in healthy (28%, p<0.05) and preeclamptic placentas (32%, p<0.05) using 1 mM Ca2+ promoting the dissociation of a eNOS from it's inhibitor caveolin. Pravastatin and Geldanamycin (Hsp90 inhibitor) cotreatment increased microsomal eNOS activity. Pravastatin treatment had no significant effects on Ser1177 phosphorylation of eNOS in either healthy or preeclamptic placentas. Pravastatin induced arginine uptake of placental microsomes in both healthy (38%, p < 0.05) and preeclamptic pregnancies (34%, p < 0.05). CONCLUSIONS: This study provides a novel mechanism of pravastatin action on placental NO metabolism. Pravastatin induces the placental microsomal arginine uptake leading to the rapid activation of eNOS independently of Ser1177 phosphorylation. These new findings may contribute to better understanding of preeclampsia and may also have a clinical relevance.

[Intra-articular steroid and hyaluronic acid treatment of internal derangement of the temporomandibular joint]. / Az állkapocsízületi károsodás kezelése szteroiddal, illetve hialuronsavval.

INTRODUCTION: Derangement of the temporomandibular joint complicates everyday life, due to the masticatory malfunction and the continuous pain sensation of the head and facial region. The therapy is multidisciplinary and varying. In case of the inefficiency of conservative therapy, minimally invasive intervention is needed with intraarticular injection. AIM: The aim of our study was to examine whether hyaluronic acid injection is more beneficial compared to corticosteroid in 37 joints. We also examined whether the efficacy of the therapy is influenced by hyaluronic acid molecular weight and the used protocol. METHOD: Wilkes stage, maximal mouth opening and the Visual Analogue Scale were determined pre-operatively and 6 months later. Corticosteroid application was performed once, hyaluronic acid was injected on a weekly bases 3 times in a row, by use of low (6-10 × 105 dalton) or high molecular weight (24-36 × 105 dalton) preparations. RESULTS: The medical state of the patients treated with corticosteroid temporarily improved, but the symptoms returned. Due to hyaluronic acid treatment, significant improvement was revealed in all parameters (pwilkes<0.0001; pmouth-opening = 0.0002; pVAS<0.0001). There was no significant relapse (T = 2.05). The third administration of hyaluronic acid resulted in a significant improvement of the Visual Analogue Scale compared to the first and second injection (T3.-1. = 20.37; T3.-2. = 9.57). CONCLUSIONS: Comparing the two agents we can state that hyaluronic acid was significantly more effective and its application for three times seems to be the most effective treatment decreasing the symptoms. The high molecular weight solution was more effective in increasing mouth opening. In contrast to hyaluronic acid, corticosteroid had no prolonged effect in higher Wilkes stages. Orv Hetil. 2018; 159(36): 1475-1482.