By Gordon J. Christensen, DDS, MSD, PhD
Crown lengthening — laser, electrosurgery, or bone removal?
You know the many times when there is not enough sound tooth structure to provide retention for a planned crown or fixed prosthesis abutment. When should you do crown lengthening and with what?
It is desirable to have at least 1 mm to 2 mm of tooth structure for a ferrule attachment for the planned crown. If 1 mm to 2 mm of sound tooth structure is not available, crown lengthening is necessary.
The following are desirable biologic width relationships:
- The gingival crevice = 1 mm
- The junctional epithelium = 1 mm
- The gingival fiber attachment = 1 mm.
On probing the gingival crevice, if you find 2 mm to 3 mm or more of unattached gingiva, simple gingival removal with a laser or electrosurgery is the preferred procedure, leaving about 1 mm of gingival sulcus and providing enough tooth structure for an adequate ferrule.If excess gingival sulcus is not present, bone removal is necessary. A gingival flap should be raised, some bone removed, the flap sutured, and healing time allowed before doing the tooth preparation.
Gordon J. Christensen Guide for Preferred Clients Jan./Feb. 2011, Vol. 16, Issue 1See our featured DVD V4346 — Easy Crown Lengthening with Dr. Jon Suzuki.Click here to read more clinical tips and current research from Dr. Gordon Christensen.Author bioDr. Gordon Christensen is a practicing prosthodontist in Provo, Utah, and a Diplomate for the American Board of Prosthodontics. He is the founder and director of Practical Clinical Courses, an international continuing education organization initiated in 1981 for dental professionals. Dr. Christensen is a cofounder (with his wife, Rella) and senior consultant of CLINICIANS REPORT (formerly Clinical Research Associates), which has conducted research in all areas of dentistry since 1976. Dr. Christensen is an adjunct professor for Brigham Young University and the University of Utah.
