Panels for a suspended ceiling of the torsional spring type are disclosed. Such panels can include: a circumferential edge configuration that preserves a very tight tolerance between a surface bearing against a foot portion of a T-bar and a face of the panel; and/or reinforcing ribs in the form of T-bars whose foot portions are inserted between the laminae of a typical ceiling panel. Each circumferential side edge configuration is multifaceted and includes: a first surface intersecting the back surface; a second surface intersecting the first surface and substantially parallel to the face surface; a third surface intersecting the second surface and substantially orthogonal to the face surface; and a fourth surface intersecting, and being beveled relative to, the third surface. The length of the first surface will vary in close proportion to the variations in the thickness of a new panel, which makes the machined back-to-face distance very uniform.