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What is In order to maintain the health of the tissue, beneath a pontic it is desirable to : and explain in detail?
Gingival surface of pontic: 
• In order to maintain the health of the tissue beneath a pontic it is desirable to
— Have passive contact with ridge without blanching of the tissue.
— Have minimal tissue contact
• The gingival surface of a pontic should be concave buccolingually and convex mesiodistally.
• Highly glazed porcelain is the material of choice to contact with the ridge.
• Rough gingival surfaces accumulate plaque and cause irritation.
• Patients maintenance (flossing) is more important than the pontic design itself.