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Children with a tongue-thrust habit in an experimental group used circumoral myofunctional exercise for three to six months to determine the effect of the exercise on the position of anterior teeth.

Silver amalgam restorations have been placed for more than a century, with excellent and with unsatisfactory results. The appearance of an amalgam restoration is dependent on cavity design and preparation, selection of alloy, manipulation of alloy and mercury, contouring and finishing procedures, and age and environment of the restoration. Changes have occurred in amalgam during the years. A recent available dental alloy addition is a dispersion strengthened system. Another system being studied experimentally substitutes about 10 weight percent of gold for silver in the alloy. It is hoped that these new systems will provide dental amalgam with improved clinical quality

Today’s emphasis on preventive dentistry is an attempt to improve our national dental health. In what better area can we practice prevention than with our child population?

A large collection of avian Mycoplasmacultures was used in studies to improve and develop biological and biochemical characterization techniques. Differential patterns among 11 avian serotypes were shown by carbohydrate fermentation, tetrazolium- and methylene blue-reduction reactions, breakdown of arginine, and the formation of film on egg yolk-agar. Some cultures fermented as many as 14 carbohydrates. Polyhydric alcohols and pentoses were among the compounds fermented. An improved procedure for determining methylene blue reduction by Mycoplasmawas developed. These simple, rapid procedures are reproducible and should be useful in grouping Mycoplasmaisolates prior to definitive identification by serological or other means.

Procedures with potential value for identification and purification of Mycoplasmawere applied to over 240 cultures representing 11 of the 12 known avian serotypes. Growth was tested at pH 5.5 and 9.5, at 25 and 42 C, in serum-free media, and in the presence of (i) 1% bile salts, (ii) 3% NaCl, and (iii) 0.02% methylene blue. One avian Mycoplasmaserotype grew in broth containing 1% bile salts. Two of 11 avian serotypes were resistant to 0.02% methylene blue. A number of Mycoplasmastrains grew at 42 C or in a pH 9.5 medium. Usefulness of these procedures for purifying cultures of Mycoplasmais discussed.