98%
921
2 minutes
20
Background: The primary issue in managing edentulous patients is the severely resorbed mandibular ridge, particularly in older individuals with diminished adaptive capacities. This compromised situation leads to the fabrication of inadequate dentures that lack retention and stability, potentially causing psychosocial issues.
Aim: To determine the difference in retentive capacity between three attachment systems in implant-retained overdentures.
Methods: Three edentulous mandibular models were fabricated using heat-cured polymethacrylate resin, with two implant replicas placed in the intra-foraminal region of each model. 30 acrylic resin mandibular overdentures were fabricated with provisions for three different overdenture attachment systems: A prefabricated ball/O-ring attachment, a locator attachment system, and an equator attachment system. Each model was subjected to 15000 pulls using a universal testing machine to remove the overdenture from the acrylic model and the force data were recorded.
Results: The ball/O-ring attachment system demonstrated superior retentive capacity for 15 years, while the locator and equator attachment systems maintained excellent retentive capacity for 5 years.
Conclusion: The ball/O-ring attachment system outperformed better than the other two attachment systems regarding retentive capacity. The locator and equator attachment systems presented sufficient retentive abilities until 15000 cycles. After 7500 cycles, significant differences in retentive force between the systems evolved.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11948192 | PMC |
http://dx.doi.org/10.5662/wjm.v15.i3.101057 | DOI Listing |
Cureus
August 2025
Department of Orthodontic Science, Graduate School of Medical and Dental Sciences, Institute of Science Tokyo, Tokyo, JPN.
Purpose Improved superelastic nickel-titanium (Ni-Ti) alloy wires (ISWs) can be used not only for aligning but also for closing the extraction space. The objective of this study was to measure and compare the force and moment generated during mandibular molar protraction using an ISW combined with either short or long hooks under simulated crowded dentition conditions. Materials and methods Assuming crowded dentition following mandibular first premolar extraction, we designed a three-tooth model simulating the canine, the second premolar, and the first molar.
View Article and Find Full Text PDFChem Sci
August 2025
Department of Chemistry, University of Houston Houston Texas 77204 USA
Quantum mechanical tunnelling significantly influences the reactivity of strained ring systems, yet strategies for controlling such reactivity remain largely unexplored. Here, we identify geminal hyperconjugation, , electron delocalization between σ-bonds attached to a common atom, as a decisive electronic factor in governing heavy-atom tunnelling reactions involving three-membered rings. We illustrate this through a case study of the oxepin (1') ⇌ benzene oxide (1) equilibrium, recently shown to undergo solvent-controlled tunnelling at 3 K (, 2020, , 20318).
View Article and Find Full Text PDFFront Bioeng Biotechnol
August 2025
Department of Sports Medicine, The First Affiliated Hospital, Guangdong Provincial Key Laboratory of Speed Capability, The Guangzhou Key Laboratory of Precision Orthopedics and Regenerative Medicine, Jinan University, Guangzhou, Guangdong, China.
Introduction: During the healing process, the functional gradient attachment of the rotator cuff (RC) tendon-bone interface fails to regenerate, which severely impedes load transfer and stress dissipation, thereby increasing the risk of retears. As a result, the treatment of rotator cuff tears remains a significant clinical challenge.
Methods: In this study, a dual-crosslinked hyaluronic acid/polyethylene glycol (HA/PEG) hydrogel scaffold was synthesized using hyaluronic acid and polyethylene glycol as base materials.
Child Prot Pract
April 2025
Department of Criminal Justice & Legal Studies, University of Mississippi, Oxford, MS, USA.
Fetal exposure laws mandate child welfare system referral for infants exposed to substances. Though these laws are relatively common, examinations of the consequences of child welfare system involvement for infants exposed to substances are less frequent. The purpose of this paper was to examine the impact of out-of-home placement at 18 and 36 months for substance-exposed infants.
View Article and Find Full Text PDFBiosens Bioelectron
September 2025
Tianjin Key Laboratory of Life and Health Detection, Life and Health Intelligent Research Institute, Tianjin University of Technology, Tianjin, 300384, PR China. Electronic address:
Wearable sweat sensors offer noninvasive health monitoring through multiplexed biomarker analysis, delivering real-time diagnostics with continuous operational capability. However, chronic cutaneous interface hydration during prolonged monitoring induces adhesive delamination phenomena that manifest as signal attenuation, which fundamentally limits their clinical reliability. To address this challenge, we developed a thermodynamically adaptive polymer interface combining three functional components: mussel-inspired catechol moieties for moisture-tolerant adhesion, hydrophobic acrylates ensuring mechanical stability, and N-isopropylacrylamide enabling thermal responsiveness.
View Article and Find Full Text PDF