Purpose: Surface characteristics of orthodontic miniscrews might affect survival rates and removal torque values (RTVs). This experimental study aimed to clarify whether and why a microporous or nanoporous surface promotes higher survival rates and RTVs for orthodontic miniscrews.
Methods: Using a split-leg design, one set each of nonporous (sham control, n = 24) and microporous (control, n = 6), and three sets of nanoporous (experimental, n = 6 per set) miniscrews were implanted in the tibias of 12 New Zealand rabbits and immediately loaded with 1.5 N nickel-titanium coil springs for 12 weeks. The surface morphology, micropores, and nanotube diameters of the miniscrews were examined using scanning electron microscopy and field-emission scanning electron microscopy. The surface composition and thickness were determined using Auger electron spectroscopy. The survival rates and RTVs of each set were assessed.
Results: The nanoporous miniscrews had higher survival rates, RTVs (p < 0.001), and thicker nanotube oxide thicknesses (p < 0.001) than the nonporous and microporous miniscrews. The nonporous and microporous miniscrews had no nanotube structures. The surface oxide composition was titanium dioxide (TiO). The threshold RTV, TiO thickness, and nanotube diameter of nanoporous miniscrews needed to promote the experimental survival rate to 100% was determined to be 6.6 ± 0.8 N-cm (p < 0.05), 22.5 ± 4.8 nm (p < 0.05), and 17.6 ± 2.3 nm or above, respectively.
Conclusion: Nanoporous surfaces promoted higher survival rates and RTVs than microporous miniscrews. This could be due to TiO nanotube structures with thicker oxide layers in nanoporous miniscrews.
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http://dx.doi.org/10.1007/s00056-022-00398-3 | DOI Listing |
Acta Orthop
January 2025
Department of Surgical Sciences, Section for Orthopaedics, Uppsala University, Uppsala, Sweden.
Background And Purpose: Evidence for long-term outcomes following acetabular fractures in older adults is limited. We aimed to evaluate mortality, complications, and need for subsequent surgical procedures in operatively and nonoperatively treated older patients with acetabular fractures.
Methods: Patients aged ≥ 70 years with acetabular fractures treated at Uppsala University Hospital between 2010 and 2020 were included.
J Invasive Cardiol
January 2025
Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Cardiovascular Diseases, China; State Key Laboratory of Cardiovascular Diseases, Zhongshan Hospital, Fudan University; NHC Key Laboratory of Ischemic Heart Diseases; Key Laboratory of Viral Heart Diseases, Chinese Academy of Medical Sciences; National Clinical Research Center for Interventional Medicine, Shanghai, China.
Objectives: The ValveClamp system (Hanyu Medical Technology) is a novel transcatheter edge-to-edge repair (TEER) system designed for ease of operation; however, there is a lack of data on its application in secondary mitral regurgitation (SMR). The authors report the mid-term outcomes of TEER using the ValveClamp system in SMR.
Methods: The study prospectively analyzed consecutive severe SMR patients who underwent transapical ValveClamp implantation at 10 Chinese centers.
Eur J Cardiothorac Surg
January 2025
Division of Cardiovascular Surgery, Department of Surgery, University of Pennsylvania, Philadelphia, PA, USA.
Objectives: The aim of this study was to determine the indication and optimal timing for performing a hemiarch procedure in patients undergoing valve-sparing root replacement (VSRR).
Methods: We conducted a retrospective study on 986 patients undergoing VSRR at three tertiary care centres. Inclusion criteria were all patients undergoing elective VSRR.
J Infect Dev Ctries
December 2024
Department of Neurosurgery, The third affiliated hospital, Sun Yat-Sen University, Guangzhou, China.
Introduction: Cryptococcal meningitis (CM) combined with intracranial hypertension is associated with a poor prognosis. This study aimed to investigate the therapeutic efficacy and prognostic factors of ventriculoperitoneal (VP) shunt in non-human immunodeficiency virus (HIV) CM patients with intracranial hypertension.
Methodology: A total of 136 non-HIV CM patients with intracranial hypertension treated in our hospital from July 2010 to December 2019 were retrospectively included.
Neoplasma
December 2024
Department of Pediatric Hematology and Oncology, National Institute of Children's Diseases, Faculty of Medicine Comenius University, Bratislava, Slovakia.
Pediatric central nervous system (CNS) tumors represent 20-25% of childhood malignancies, with 35-40 new cases annually in Slovakia. Despite treatment advances, high mortality and poor quality of life in a lot of cases persist. This study assesses the clinical features, treatment modalities, and survival rates of pediatric CNS tumor patients in the single largest center in Slovakia.
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