It is necessary when designing removable partial dentures to be fixed,
stable and well supported for improving patient comfort, and decreasing
damages on soft tissues and dental abutments, the alveolar ridge has a
strong influence in planning for
treatment and interpretations
biomechanical when treated with removable partial dentures, and have
four shapes in the sagittal plane which are horizontal shape, concave
shape, distal ascending shape and descending shape.