Effect of titanium dioxide and zirconium dioxide nanoparticle incorporation on the thermal conductivity of heat-activated polymethylmethacrylate denture base resins: An in vitro experimental study.

Aim: The aim is to determine thermal conduction by heat-activated polymethylmethacrylate (PMMA) infiltrated with 1 weight% Titanium Dioxide (TiO2) and 1 weight% Zirconium Dioxide (ZrO2) nanoparticles and to compare with that of conventional PMMA.

Study Setting And Design: In vitro experimental study.

Materials And Methods: Eighteen disc shaped specimens with a thickness of 5 mm and diameter of 50 mm, were fabricated and grouped according to the material used: Group B1 (resin infiltrated with 1 weight% TiO2), Group B2 (resin infiltrated with 1 weight% ZrO2), and Control Group B3 (heat-activated conventional PMMA resin).

Prosthetic management of posttraumatic external auditory canal atresia: A rare cause of conductive hearing loss.

Acquired external auditory canal (EAC) atresia is an infrequent entity which can originate from a number of different causes including trauma, infection, neoplasia, inflammation, and radiotherapy. Posttraumatic atresias are exceptionally rare, only 10% of atresias are attributed to trauma in most of the series. The management of stenosis of the EAC is challenging as it is associated with residual hearing loss and late recurrence.