Optimization of materials for a user-formed mouthguard
A mouthguard that can be custom formed by the user at the time of need to achieve optimum fit and protection is required for sports and clinical applications. This study has evaluated two silicone-based polymer systems found sufficiently workable to be molded to the user's mouth. Compositions were optimized for setting time and mechanical properties by varying the proportions of catalyst, cross-linking agent, and filler. Mechanical tests showed the optimized silicones to have lower tensile and tear strengths and higher penetration and rebound than most present mouthguard materials. Detailed measurements of compressive stress-strain, coupled with a stress analysis of conditions in actual mouthguard use, indicate that the optimized silicone polymers possess more than adequate strength and durability for a user-formed mouthguard.
Comparison of the Hardness, Energy Absorption and Water Absorbability of Polymeric Materials Used in the Manufacture of Mouthguards
Background. Mouthguards constitute an inseparable feature of injury prevention for the head and mouth area. Due to growing expectations regarding comfort of usage and resistance parameters strictly determined quality standards must be established for such equipment. These resistance parameters are usually dependent on the type of the material they were made of and the technology applied. Objectives. The aim of the present study was to compare the hardness, elasticity and absorbability of polymeric materials used to produce mouthguards as well as to identify which materials have the most favourable resistance and functional properties. Material and Methods. Samples of polymeric material obtained during deep moulding, canning and thermal injection were utilised to measure hardness, resilience and absorbability. Results. On the basis on the researched material, it is recommended that the following be used in the production of mouthguards: Impak® in 1 : 1 and 1.5 : 1 proportions, Elastosil®, double-laminated Erkoflex® and Corflex®, as these materials ensure optimal hardness and energy absorption. The studied material was shown to have an acceptable level of absorbability (up to 0.5% in mouthguards), but it was the Corflex Orthodontic material that exhibited the lowest values in this respect. Conclusions. Corflex Orthodontic process using the thermal injection technique is the most suitable material for preparing mouthguards (Dent. Med. Probl. 2015, 52, 1, 78–85).
Antimicrobial activity in pulp extract of Neem(Azadirachta indica Linn.)
Antimicrobialactivityin leaf extract of neem ( Azadirachta indica ) against human pathogenic bacteria. E.coli, Staphylococcus aureus, Pseudomonas aeruginosa , Salmonella typhimurium, Bacillus pumilus. Antimicrobia l activities of alcoholic extracts of neem leaves were used. Varying concent ration of each extracts 200mg/ml, 150 mg/ ml,100mg/ml, 50mg/ml, 25mg/ml prepared by using disc diffusion method. When compared with gentamycin 200mg and gentamycin 10mg, the methanol and ethanol extract shows maximum inhibition on Bacillus pumillus, Pseudomonas aeruginosa and Staphylococcus aureusin an asending order.