This study investigates the retention load (RL) between ZrO₂ primary crowns and secondary polyetheretherketone (PEEK) crowns made by different fabrication methods with three different tapers. Standardized primary ZrO₂ crowns were fabricated with three different tapers: 0°, 1°, and 2° (n = 10/group). Ten secondary crowns were fabricated (i) milled from breCam BioHPP blanks (PM); (ii) pressed fro...

To investigate the effects of abutment taper angles on the fracture strength of dental implants with TIS (taper integrated screwed-in) connection. Thirty prototype cylindrical titanium alloy 5.0mm-diameter dental implants with different TIS-connection designs were divided into six groups and tested for their fracture strength, using a universal testing machine. These groups consisted of combina...

The current investigation examines periodic vortex shedding from surface mounted pyramids with taper ratios (2*height/base diameter) of 7.6 to 14.3 in a thin boundary layer using surface pressure measurements along the obstacle faces. Over the lower portion of the pyramids (y/h<~0.5) regular periodic vortex shedding was observed. Near the tip, a large time-scale structure was observed. This str...

The present study compared changes in cuff pressure by head and neck position between high-volume low-pressure (HVLP) and taper-shaped (taper) cuffs in a prospective randomized clinical trial. Methods. Forty patients were intubated using tracheal tubes with either HVLP (n = 20; HVLP group) or taper-shaped (n = 20; Taper group) cuffs. Initial cuff pressure was adjusted to 15, 20, or 25 cmH2O in ...

Light propagation is analyzed in thermally expanded core (TEC) fibers with graded-index profile. Used as power mixers among others, their core structure at the boundary between the heated and non-heated regions is represented by linear taper. Ray optics is used as the transverse taper dimensions are large relative to the wavelength of propagating light. Trajectories of meridian rays are derived...

Assessment of the head-stem taper junction requires the estimation of material loss from the taper surfaces of both femoral head and stem. This paper describes a method for the measurement and analysis of material loss from the modular taper junction of hip replacements, in particular femoral stem tapers where generally the entire taper surface has been engaged. In such cases no direct unengage...

BACKGROUND No documentation in the literature about taper of cast posts. This study was conducted to measure the degree of cast posts taper, and to evaluate its suitability based on the anatomy aspects of the common candidate teeth for post reconstruction. METHODS Working casts for cast posts, prepared using Gates Glidden drills, were collected. Impressions of post spaces were made using poly...

OBJECTIVES Dependence on prescription opioids (PO) is a growing problem. Although most research with buprenorphine has focused on heroin-dependent populations, we hypothesize that individuals dependent on PO display characteristics that may predict different outcomes in treatment, particularly in short-term taper procedures in which comorbidities such as pain conditions may complicate taper. ...

OBJECTIVES An ongoing prospective study to investigate failing metal-on-metal hip prostheses was commenced at our centre in 2008. We report on the results of the analysis of the first consecutive 126 failed mated total hip prostheses from a single manufacturer. METHODS Analysis was carried out using highly accurate coordinate measuring to calculate volumetric and linear rates of the articular...

A modular femoral head-neck junction has practical advantages in total hip replacement. Taper fretting and corrosion have so far been an infrequent cause of revision. The role of design and manufacturing variables continues to be debated. Over the past decade several changes in technology and clinical practice might result in an increase in clinically significant taper fretting and corrosion. T...