J Periodontol • April 2005 503 P resurgical planning is essential to obtain esthetic and functional implants, and a variety of tech- niques is presently available. 1 In cases of compromised host bone or increased esthetic demand, more detailed infor- mation is required, which in turn, justi- fies the use of more elaborate planning techniques. Multiplanar computerized tomography (CT) is the most frequently used aid in treatment planning, and various software programs enable precise, preoperative evaluation of the patient’s 3-dimensional anatomy for implant placement. Several methods have been proposed to transfer the planning stage to surgery. Computer- aided rapid prototyping of surgical guides apparently transfers the 3-dimensional image accurately to the surgical site, translating a sophisticated plan to the surgical field. 2-6 However, no definitive evidence is available. Sarment et al. compared the traditional surgical guide with the stereolithographic surgical guide in vitro, and reported that implant place- ment was improved by using a stereo- lithographic surgical guide. 5 These authors also demonstrated in two clini- cal cases that the use of a stereolitho- graphic surgical guide allowed precise translation of the treatment plan directly to the surgical field. 3 van Steenberghe et al. reported a nearly perfect match between the positions and axes of the planned and placed implants, when a stereolithographic surgical template was used in two cadavers and eight patients (15 implants). 4 Tardieu et al. presented Clinical Application of Stereolithographic Surgical Guides for Implant Placement: Preliminary Results Giovanni A.P. Di Giacomo,* Patricia R. Cury, † Ney Soares de Araujo, † Wilson R. Sendyk,* and Claudio L. Sendyk* Background: The success of implant-supported restorations requires detailed treatment planning, which includes the con- struction of a surgical guide. Recently, computer-aided rapid prototyping has been developed to construct surgical guides in an attempt to improve the precision of implant placement. The aim of the present study was to evaluate the match between the positions and axes of the planned and placed implants when a stereolithographic surgical guide is employed. Methods: Six surgical guides used in four patients (three women, one man; age from 23 to 65 years old) were included in the study and 21 implants were placed. A radiographic template was fabricated and computer-assisted tomography (CT) was performed. The virtual implants were placed in the resulting 3-dimensional image. Using a stereolithographic machine, liquid polymer was injected and laser-cured according to the CT image data with the planned implants, generating three surgical guides, with increasing tube diameters corresponding to each twist drill diameter (2.2, 3.2, and 4.0 mm), for each surgical area. During the implant operation, the surgical guide was placed on the jaw- bone and/or the teeth. After surgery, a new CT scan was taken. Software was used to fuse the images of planned and placed implants, and the locations and axes were compared. Results: On average, the match between the planned and the placed implant axes was within 7.25° ± 2.67°; the differ- ences in distance between the planned and placed positions at the implant shoulder were 1.45 ± 1.42 mm, and 2.99 ± 1.77 mm at the implant apex. In all patients, a greater distance was found between the planned and placed positions at the implant apex than at the implant head. Conclusions: Clinical data suggest that computer-aided rapid prototyping of surgical guides may be useful in implant place- ment. However, the technique requires improvement to provide better stability of the guide during the surgery, in cases of uni- lateral bone-supported and non-tooth-supported guides. Further clinical studies, using greater number of patients, are necessary to evaluate the real impact of the stereolithographic surgical guide on implant therapy. J Periodontol 2005;76:503-507. KEY WORDS Dental implantation; dental implants; patient care planning; surgery, computer-assisted; tomography, computer-assisted. * Department of Periodontics and Implantology, School of Dentistry, University of Santo Amaro, São Paulo, Brazil. † Department of Oral Pathology, School of Dentistry, University of São Paulo, São Paulo, Brazil.