Remaining Time

Guido Schiroli

Guido Schiroli graduated from University of Genoa, Italy in 1988 and post graduated in 1991 at the same University. He completed the Master of oral surgery at the Harvard University ( 1996 ). Lecturer of the Master of implantology at La Sapienza in Rome 2005-2009 . Adjunct professor at La Sapienza University in Rome (2006- 2009). From 2010 adjunct professor  at the University of Genoa. Coordinator of Master for implantology at University in Genoa and Tutor for impantology at the clinical department of University in Genoa. Member from 2001 of the ICOI (International Congress Oral Implantologist) and member of EDI (European Dental Implantologist). Is well-published in various scientific and professional journals. He delivered presentations both nationally and internationally on various meetings focusing in implant and prosthetic dentistry. Dr. Schiroli is a founding member of the Simplant Academy and Simplant study club past President of the Computer Aided Implantology Academy (CAI Academy) for  the biennium 2007-2008. He currently maintains a private practice limited to implantology and prosthodontic in Genoa.

Guided Zygomatic Implant Placement by Using Intrasinusal Device: A Ten Years Follow-Up

In recent years, zygomatic implants have been advocated as a graftless solution for prosthetics and functional rehabilitation of highly resorbed maxillae (14-16). After a long follow-up period a good success rate was reported for a specific clinical protocol by Branemark in 1998 (17) and 2004 (18). Thus zygomatic implants thus now offer a concrete treatment option, thanks to the predictable anchorage in the dense zigomatic bone, and should be used in conjunction with the placement of 3-4 conventional implants in the premaxilla (10). This approach markedly reduces treatment time and morbidity comparing the traditional reconstructive pre-implant surgeries  . Despite the advantages and good success rate, the anatomical risks and complications must be taken into account (25-29). Image-guided implantology is today a clinical reality for implant treatment in terms of accuracy, mini-invasive procedures and final restorative results (34-36). The simplified surgical protocol used in conjunction with 3D anatomical diagnosis, safe flapless surgery, and immediate-loading protocols, represent major improvements, enabling many different clinical situations to be resolved.

The accuracy of these procedures has been extensively documented (35-37). Thus current implant surgery can now offer safe and graftless procedures. Computer-guided surgery for zygomatic implant placement was first described in 2000 by Schramm A. et al. (40). The accuracy of guided surgery for zygomatic implant placement using a stereolithografic surgical guide has been investigated in human cadavers by van Steenberghe et al (41). Despite to that  a zygomatic guided surgery represent still today a challenge due to the difficult during the drill guidance related to the length of implants and anatomical conditions . A data collected from several scientific contributions regarding the accuracy of guided stereolitographic surgery indicate the angulations as a most deviation parameter. Thus a guidance of a 3550 mm of implants lengths in addition to the drill control represent a major technical problem . A coordinate protocol and specific surgical kit are still necessary to asses the guided surgery as a predictable clinical treatment . A series of four clinical case have been treated with an original protocol including  a specific clinical steps and customized surgical kit dedicated to the zygoma osteotomies.

The proposed protocol has the following advantages:
1) Anatomical evaluation of the premaxilla prior to placement of zygoma implants,
2) More accurate final guide stabilization, 
3) Planning in conjunction with a definitive position of the guide, 
4) Virtual surgery is performed on the stereolithographic model before actual surgery, 
5) Customised surgical kits are employed.
Despite the limited number of cases and the short follow-up period, in our opinion the results of this surgical procedure appear encouraging. Despite the difficulties inherent in driven angulation of the osteotomy, due to the length of the zygomatic implants, in all cases a correct position was achieved, in line with that planned. Further study and randomized clinical trials will be needed to assess the predictability of the procedure.

Results

Zygomatic implant success was defined by the following criteria: clinical stability with no signs of mobility; absence of pain and infection; absence of peri-implant radiolucency; prosthetically valid implant position. Of a total of 25 implants, 17 in the premaxilla, seven in the zygomatic bone, and one in the pterygoid bone, we obtained the following results: two primary implants in the premaxillary area failed (they were replaced prior to the zygomatic step) due to lack of bone integration; no zygomatic or pterygoid implants failed. During the postoperative period, swelling in the infraorbital region with bruising were recorded in all cases. Pain proved mild and was effectively treated with conventional analgesics. Follow-up at 4-39 months showed good aesthetic, phonetic and functional results.