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The conventional investing technique is used most commonly for casting. Inspite of the popularity of this technique, it is very time consuming. To save time of the patient, dentist and dental laboratory technician, accelerated casting technique can be used. This study uses different bench set and different burnout temperatures and has been carried to investigate their effects on marginal fit and surface roughness. A total of 40 wax patterns were made simulating the artificial crown from the first master die and 20 rectangular wax patterns were made from the second master die. Twenty castings simulating the crown and 10 castings of rectangular plates were obtained by short protocol represented as Group A and C, similarly the remaining castings were obtained by standard protocol and represented as Group B and D. Marginal discrepancy of both Group A and B were determined by using Travelling microscope, whereas Perthometer was used for quantitative evaluation of average surface roughness of both Group C and D. Scanning electron microscope evaluated the surface roughness qualitatively for the specimens of both Groups C and D. The obtained values of Group A and C and Group C and D were subjected to statistical analysis. Qualitative analysis of Group C and D were done. Accelerated/short protocol gives similar results in terms of marginal fit and surface roughness as compared to the conventional/standard protocol and is definitely a time saving procedure.

Tongue-palate contact is necessary for the production of normal speech, and the proper location of the tongue on the palate during certain sounds is important. Partial glossectomy leads to difficulty in tongue-palate articulation during speech, and it becomes difficult for a patient to reach the palate with the tongue to form certain sounds. In-depth knowledge of the production of different sounds can be used as a diagnostic aid in determining the thickness of the palatal augmentation prosthesis fabricated to rehabilitate such patients. A functional wax technique is used to make a functional impression of tongue-palate contact during the speech.

BACKGROUND Human teeth and bones consist of hard and soft tissues. Preparing calcified tissues for histological analysis by decalcification is a time-consuming procedure, and the quality of the sections thus obtained is dependent on the speed with which decalcification occurs, as well as the chemistry of the decalcification agent. The present study was intended to identify the method that combines the highest quality of stained sections with a short period of time. METHODS 50 extracted premolars were subjected to decalcification using 10 % Formic acid and 5 % Trichloroacetic acid (TCA). The efficacy of decalcifying agents was evaluated by recording the time taken by particular acid to decalcify the tooth completely. The preservation of morphological characteristics was assessed on the basis of ease of sectioning, uniformity of staining, damage to odontoblast layer, retraction of pulp and fraying of dentinal tubules. RESULTS Comparatively decalcification was faster with 5 % TCA than 10 % Formic acid. Whereas, 10 % formic acid was more considerate on soft tissues than 5 % TCA. All the results were statistically significant. CONCLUSIONS Samples decalcified with 10 % formic acid gave fairly good results, so it can be used in cases of diagnostic urgencies. KEY WORDS Teeth, Decalcification, Acids, Histopathology

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