3D Digital Dentistry
The Navigation System for Dental Implantology
Dr. Dr. Steffen Hohl, Buxtehude
Almost without being noticed, GPS (Global Positioning System) has been established in our daily life. An unknown destination is no longer a reason for today’s car drivers to look onto a road map. The destination is simply entered into the GPS or navigation device. These devices then perform an automatic calculation of the route and the estimated time of arrival. Possible complications like traffic jams, construction sites or accidents are naturally taken into account.
In dental implantology, GPS or navigation systems are now also available in order to accurately position implants. But which advantages does computer guided navigation bring to patients and clinicians? Can patients possibly be informed about the risks and uncertainties even before implant surgery takes place? And above all: how can computerized navigation get seamlessly integrated into daily working routines?
This paper is intended to answer all those questions. The following example cases were realized with SimPlant Pro planning software (Materialise Dental, Leuven, Belgium) and corresponding SurgiGuide drill guides were used as surgical drilling templates.
PATIENT 1: MUCOSA-SUPPORTED SURGIGUIDE WITH IMMEDIATE LOADING
The 66-year-old female patient suffered from insufficient retention of her complete lower denture. After an implantological consultation in our clinic, the patient decided to have four Xive implants (DENTSPLY Friadent, Mannheim, Germany) inserted in the interforaminal region. This procedure could be realized by means of a mucosa-supported surgical guide and transgingival implant placement. We had already prepared the new mandibular full prosthesis pre-operatively. This procedure offers the patient the advantage of receiving a final prosthesis immediately after implant insertion by using pre-operatively manufactured Friadent AuroBases and galvanic caps. Thereby the implants get immediately loaded.
1 - Scan prosthesis for a mucosa-supported SurgiGuide with four drilling holes at the planned implant regions.
2 - Planning screen in SimPlant Software (Materialise Dental)showing the different slice planes of the dental CT.
7 - Immediately after transgingival implant placement inserted Friadent AuroBases with pattern resin key.
8 - The modified denture with pre-operatively fabricated galvanic caps. These will be incorporated „chairside“.
PATIENT 2: BONE-SUPPORTED SURGIGUIDE
This 72-year-old male patient has an edentulous maxilla. The six Xive implants were inserted using a bone-supported surgical guide. In order to speed up fabrication of the prosthesis, implant impressions with repositioning posts were already performed intra-operatively. After a healing phase of three months the Xive implants could be immediately restored with Friadent CeraBases and galvanic caps. The pre-operatively fabricated denture could then be replaced by a telescopic saddle bridge with ceramic veneering.
2 - Planning screen SimPlant with overview on the left side, showing bone density around implant in region 13. Here we have a bone density type D2.
PATIENT 3: TOOTH-SUPPORTED SURGIGUIDE
The 53-year-old female patient presented herself in our practice with a free-end situation in her left upper jaw. We had extracted teeth 25, 26 and 27 six weeks ago. An impression of the implants with repositioning posts was made at the time of the implant insertion. Following the concept of early loading, the patient received an all-ceramic prosthesis within just three months (this accelerated workflow in the dental laboratory and shortened the overall treatment time). Furthermore, prefabricated temporary acrylic crowns can be worked with at the time of second stage surgery, which enable a perfect modeling of soft tissues.
3 - Patient lying inside the Spiral-CT (gantry tilt zero degrees), with her head fixed for better stability.
As demonstrated by these case examples, the procedure can easily be integrated into the practical workflow. All patients described above were well-informed about their individual treatment goal by means of the SimPlant planning. The stereolithographically fabricated SurgiGuide drill guides or drilling templates and jaw models are manufactured with the highest levels of industrial precision [Rosenfeld AL et al., 2006; Miller RJ, 2006]. The implant position is therefore determined three-dimensionally with utmost accuracy and can be transferred into the mouth. All necessary interventions for optimizing bone in the recipient area are already pre-operatively known to the patient and the surgical team and can be demonstrated exactly with the planning software. In SimPlant, even osteotomy guides can be realized, which help to accurately transfer osteotomies and bone grafts. Also, placement of distractors can be performed by means of template technique. Surgery time is reduced thanks to exact planning, and use of materials can be limited to a minimum.
With large cases for implantological rehabilitation, especially bone-supported SurgiGuide drill guides are preferred [Ewers et al., 2005; Mischkowski et al., 2006]. The precision which can be obtained with this technique has already become scientifically recognized worldwide. Even intra-operative navigation with robotics cannot beat the precision of bone-supported drilling templates [Mischkowski et al., 2006]. Mucosa-supported SurgiGuide drill guides are the ideal solution for interforaminal implant insertion, which can also be combined with immediate loading situations [Casap et al., 2005; Hoffmann et al., 2005; Siessegger et al., 2001; Wittwer et al., 2006]. Nowadays computerized navigation has already become an essential part of implantology. Its wide range of possibilities has made computer guided implantology the currently most promising discipline in dentistry.
For implant dentistry, SimPlant software offers a sophisticated tool for accurate planning of implant positions. The latter is of particular interest to us, as esthetics and functionality of an implant-supported prosthesis are determined, among other factors, by the implant position in the jaw. By means of computer- and template-planned implantology, we can now achieve esthetic results which could be obtained rarely or not at all with conventional procedures. Drilling templates or SurgiGuide drill guides produced with stereolithographic laser-techniques are fabricated with the highest levels of industrial precision and allow an exact transfer of the pre-operative planning. Benefits like shortened surgery time and reduced use of materials are just some of the additional advantages of computerized navigation.
References are available upon request from the author.
Dr. Dr. Steffen Hohl
DIC | Dental Implant Competence
Oral-Maxillofacial and Plastic Surgery
Implantology & Periodontology
D- 21614 Buxtehude
Phone +49 (0)4161 55990 • Fax +49 (0)4161 559911