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TYPES AND DESIGN FEATURES OF FACIAL AND LINGUAL FLARES: Flares are the flat or concave peripheral portions of the facial and lingual walls. There are two types of flares: 1. Primary flare 2. Secondary flare PRIMARY FLARE: It is the conventional and basic part of circumferential tie facially and lingually for an intra coronal preparation. It is very similar to long bevel formed of enamel and dentin on the facial or lingual wall, primary flares always have a specific angulation, i.e., 45° to the inner dentinal wall proper. Main function of flare is to bring the facial and lingual margins of the cavity preparations to cleansable – finishable areas. SECONDARY FLARE: Flat – plane super imposed peripherally to a primary flare Sometimes it is prepared in a hollow ground form to accommodate materials with low castability. Secondary flares may have different angulations; involvement and extent depend on their function. Indicated in very widely extended lesions bucco-lingually, results in primary flare ends with an acute angle marginal tooth structure. A secondary flare with correct angulation can create the needs obtuse angulation of marginal tooth structure. In very broad contact areas or malposed contact area.