Influence of implant/abutment joint designs on abutment screw loosening in a dental implant system.

J Biomed Mater Res B Appl Biomater

Department of Crown Bridge Prosthodontics, Nihon University School of Dentistry at Matsudo, 2-870-1 Sakaecho Nishi, Matsudo, Chiba 271-8587 Japan.

Published: November 2005

The objective of this study was to investigate the influence of implant/abutment joint designs on abutment screw loosening in a dental implant system, using nonlinear dynamic analysis of the finite element method (FEM). This finite element simulation study used two dental implant systems: the Ankylos implant system (Degusa Dental, Hanau, German) with a taper joint (taper joint-type model), and the Bränemark implant system (Nobel Biocare, Gothenburg, Sweden) with an external hex joint (external hex joint-type model). The nonlinear dynamic analysis was performed using three-dimensional finite element analysis. In comparing the movement of the taper type-joint model and external hex type-joint model, it was found that the external hex type-joint model had greater movement than the taper type-joint model. The external hex joint-type model showed rotation movement, whereas the movement of the taper joint-type model showed no rotation. It was concluded that the nonlinear dynamic analysis used in this study clearly demonstrated the differences in rotation of components in dental implant systems with taper or external hex joints.

Download full-text PDF

Source
http://dx.doi.org/10.1002/jbm.b.30328DOI Listing

Publication Analysis

Top Keywords

external hex
24
dental implant
16
implant system
16
joint-type model
16
type-joint model
16
nonlinear dynamic
12
dynamic analysis
12
finite element
12
movement taper
12
model external
12

Similar Publications

Article Synopsis
  • Higher olefins (HO) are important chemicals used to make various products including plastics, lubricants, and detergents, and their developmental toxicity was studied for regulatory purposes.
  • Five specific HO were tested on pregnant Sprague-Dawley rats at different doses (0, 100, 300, and 1000 mg/kg bw/day) to assess their effects from Day 3 to Day 19 of gestation.
  • The studies found no significant maternal or fetal toxicity from HO, with a No-Observed-Adverse-Effect Level (NOAEL) of 1000 mg/kg bw/day, indicating safety for both mother and fetus at this dose.
View Article and Find Full Text PDF

Radioactivity Levels and Heavy Metal Concentration in Mining Areas in Zacatecas, Mexico.

Toxics

November 2024

División de Química, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Avda. Complutense 40, 28040 Madrid, Spain.

The state of Zacatecas (Mexico) is one of the places most affected by pollution from the mining industry. A total of 21 samples from two areas were collected (6 samples from zone A and 15 samples from zone B) to evaluate the level of radioactivity and the degree of contamination with heavy metals. The activity concentration for U and Th was within typical values but that of Ra exceeded the value of 60 Bq kg in both areas.

View Article and Find Full Text PDF

This study was conducted in Lahij city, Yemen, to evaluate the concentrations and potential health risks of natural radioactive nuclides and heavy metals in soil and drinking water. A total of 21 soil samples and 17 water samples were collected from various locations. A high-purity germanium gamma detector HPGe was used to measure the concentrations of K, Th, and Ra in all samples, along with the concentrations of heavy metals.

View Article and Find Full Text PDF

This study investigates the levels of natural and artificial radioactivity in rice samples collected from various local markets in Islamabad, Pakistan. The Ra, Th, and K activity concentrations were measured through gamma-ray spectrometry with a NaI(Tl) detector. The average activity concentrations were 1.

View Article and Find Full Text PDF

The purpose of this study was to examine the impact of abutment screw head sizes on preload stability when secured to a standard external hex implant under oblique compressive forces. Fifteen metal crowns were divided into 3 equal groups. The first group had 5 angulated cemented crowns connected to a 3-mm-tall straight hexagonal abutment with an external hex abutment screw.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!