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What is The secondary flare is necessary for several reasons. Which of the following statements is not true? and explain in detail?
The secondary flare is necessary for several reasons:

The secondary flaring of the proximal walls extends margins into the embrasures, making these margins more self-cleansing and more accessible to finishing procedures during the inlay insertion appointment and does so with conservation of dentin.
The direction of the flare results in 40o marginal metal. Metal with this angular design is burnishable; however, metal shaped at a larger angle is unsatisfactory for burnishing; metal with an angle less than 30o is too thin and weak, with a corresponding enamel margin that is too indefinite and ragged.
A more blunted and stronger enamel margin is produced because of the secondary flare.

Sturdevant operative dentistry 7th Edition, Page No:e107