The precision of surgical guides in CAD-CAM implant surgery. - ROS - 2013 - Tome 42 - N°4

PURPOSE:
This article aims at analyzing clinical trials to determine the accuracy of stereolithographic surgical guides in their various configurations and in the various clinical situations.
METHOD:
A research for articles written in English in the database PUBMED has been conducted since June, 2005 until June, 2012 according to the following criteria: "guided surgery and computed-aided surgery", "stereolithographic surgical template".
OUTCOME:
Twenty six articles were identified as relevant with regard to the subject. Ten studies feature quantitative results.
Four studies (Ozan et al. 2009 ; Cassetta et al. 2011 ; Arisan et al. 2010 , Ersoy et al. 2008 compare the precision of implants placement according to the nature of the support of the chosen stereolithographic guide. To Ozan et al. and to Cassetta et al., tooth-supported guides aremore accurate than the other guides. According to Arisan et al.,mucosa-supported guides aremore precise than the other guides while to Ersoy et al., there are no accuracy differences among the various guides.
In the six other studies, only one type of guide is used to place the implants but these studies provide us qualitative results on other parameters which could have an influence on the precision of the positioning of implants: to D'Haese et al. (2012), implants placed in the posterior maxillary region seem to deviate more than those placed in the anterior region. Same thing about long implants compared with short implants.
To the same authors as well as to Vasak et al. (2011), the thicker the mucosa is (in relation or not with the patients' smoking habits), the greater the deviations are. Besides, to Pettersson et al. (2010), the patient's movements during the preoperative and/or post-operative scanners could also have a negative influence on the precision of implants placed by guided surgery.
CONCLUSION:
Considering the large number of stages required by the guided surgery, from the making of the prosthetic project to the positioning of the stereo lithographic guide, as well as the patient's anatomy and habits and the requirements of certain protocols such as the immediate loading, a great number of unclear elements may arise.
The practitioner who would like to use this technique has to know all the ins and outs in order to limit the negative effects on the final result. He must also perfectly master the IT planning as well as the surgical technique that is sometimes different from conventional techniques. A learning curve is often necessary.