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Classification of molar extraction sites for immediate dental implant placement: technical note
Richard B Smith1, Dennis P Tarnow
1Department of Prosthodontics, Columbia University College of Dental Medicine, New York, New York 10155, USA. RSmith@SDNonline.com
Abstract:
Dental implants may be successfully placed immediately into fresh extraction sockets when primary implant stability can be attained. This article presents a new classification system for molar extraction sites that describes extraction sockets based upon the bone available within the socket for stabilization of an immediately placed implant. Three categories--types A, B, and C--are employed: the type A socket, which allows for the implant to be placed completely within the septal bone, leaving no gaps between the implant and the socket walls; the type B socket, which has enough septal bone to stabilize but not completely surround the implant, leaving gaps between one or more surfaces of the implant and the socket walls; and the type C socket, which has little to no septal bone, thus requiring that the implant engage the periphery of the socket. Treatment protocols and relevant clinical examples are presented based upon the characterization of the socket according to this classification system.