Improving dimensional stability of dental amalgam by using Nano Zinc Oxide.

Objective: To investigate the dimensional stability of dental amalgam after the incorporation of zinc oxide nano powder.

Methods: The experimental study was conducted at the Hamdard University Dental Hospital and the Pakistan Council of Scientific and Industrial Research laboratories, Karachi, from January to June, 2018. Direct precipitation method was used in which analytical grade sodium hydroxide and zinc nitrate hex hydrate were used without any further purification.

Analysis of bristle design of commercially available tooth brushes by using scanning electron microscope.

Objective: To compare the bristles of five toothbrushes types and to recommend the best design among them.

Methods: The study was conducted at Hamdard University Dental Hospital, Karachi, from June 2017 to February 2018, and comprised five different types of commercially available manual toothbrushes. Five toothbrushes from each of the selected brands were procured from a supermarket taking care that all brushes from similar brands had the same manufacturing batch number and date of manufacturing.