INTRODUCTION Root canal anatomy and canal preparation instruments affect the outcome of endodontic treatment. The purpose of this study was to determine the root surface strain (SS) generated and the extent of canal center transportation during canal shaping using 3 different nickel-titanium instruments. METHODS Simulated root canals in resin blocks (n = 10 per group) were prepared using adap...

BACKGROUND Four infrared aural canal thermometers are currently available in Japan: Genius, Thermoscan, Quickthermo, and Thermopit. We therefore tested the hypothesis that each is sufficiently accurate and precise for clinical use. METHODS For the purpose of this investigation, we considered accuracy to be the mean difference between the test thermometers and the reference thermocouple. Preci...

The modified pressure with stored equalisation (MPSE) method of soundfield equalisation is universally recommended for use in clinical practice during the real-ear measurement (REM) verification of open-canal (OC) hearing aids. This is because the MPSE method deactivates the reference microphone for aided measurements and so is not susceptible to the leakage of amplified sound from the open ear...

BACKGROUND Vestibular inputs have been shown to play a critical role in spatial navigation. In this study, we sought to evaluate whether vestibular loss due to aging contributes to impaired spatial navigation as measured by the triangle completion task (TCT). MATERIALS AND METHODS We recruited three types of participants: young controls <55 years of age, older controls ≥55 years of age, and o...

The purpose of this study was to compare and evaluate the shaping ability of the three different Ni-Ti file systems used by undergraduate students. Fifty undergraduate students prepared 150 simulated curved root canals in resin blocks with three Ni-Ti file systems ProFile (PF), Manual ProTaper (MPT), Rotary ProTaper (RPT). Every student prepared 3 simulated root canals with each system respecti...

Introduction Studies a ssessing the d iametr ic dimensions of apical anatomy repeatedly demonstrate that the bucco-lingual diameter is greater than the mesio-distal diameter— canals are predominantly ovoid throughout, not round (Figs. 1a and 1b). The technical flaw most inherent—the use of a round file of any design to clean an ovoid canal configuration —manifests as the failure to debride a su...

UNLABELLED The three well recognized tympanoplasty approaches: permeatal, postaural, and endaural, each have advantages and disadvantages. The permeatal approach is suitable only for ears with adequate canal size. The postaural approach limits visualization of the posterior eardrum margin. The endaural approach limits the view of the eardrum's anterior margin. This study describes a modified en...