Dental Tribune United Kingdom

13Implant TribuneAugust 1-7, 2011United Kingdom EditionUnited Kingdom Edition page 14DTà We change your vision. KaVo Dental Ltd. · Corinium Industrial Estate · Raans Road · Amersham, Bucks. HP6 6JL · Phone +44 1 494 733 000 · Fax +44 1 494 431 168 · www.kavo.co.uk KaVoLUX® 540 LED The new KaVoLUX® 540 LED – the 5-star light for your practice: Natural light with the highest quality, due to four LEDs of different specification and a unique optical system Uniform light-field, precisely defined and shadow-free, with an individualised light colour COMPOsave Mode for problem-free processing of the filling material, without premature polymerisation Comfortable and practical handling, due to contact-free operation and the lockable, 3D-joint Long service-life and minimum energy consumption, with the most up to date LED technology and fan-free cooling more information D epending on the ana- tomical situation, the lateralisation of the inferior alveolar nerve may be one, or perhaps the only, solution to manufacture a fixed prosthesis for a patient with a free-end situ- ation. Problems If a patient with conservable re- sidual dentition in the anterior mandibular area with a free-end situation requires an implant- supported restoration, problems may arise regarding the route of the inferior alveolar nerve. If the route of the nerve runs too far toward the crestal bone, or if there are already signs of atro- phy in the crestal part of the jaw, a restoration with a common implant may be difficult, or even impossible. Here are several solutions for this problem. One solution is the use of short implants (<10mm). The minimum length of common implant systems is 7–9mm. Therefore, the bottom line for a conventional implant should be calculated with a safety mar- gin of 2mm, provided that there are approximately 9–11mm of crestal bone. As observed in the mandible, the survival rates of 8mm long implants are similar to the survival rates of longer im- plants (Grant5 2009). Another alternative is a ver- tical augmentation with autolo- gous bone or allogenic materials. With respect to resorption, the long-term prognosis is contro- versial. Schlegel13 states a resorp- tion rate of approximately 30 per cent after five years. Moreover, this solution must be excluded for those cases in which atrophy of the jaw bone is not due to in- sufficient crestal bone, but to the crestal route of the inferior al- veolar nerve (Fig 1). This method requires the usage of pelvic bone, which implies a second surgery site. Probable rates of long-term complaints in this area are par- tially stated as 11 per cent (Cric- chio1 2003). Another option is the osteo- distraction in the lateral man- dibular area. In order to place the distractor cranially to the nerve canal, a minimum of 8mm resid- ual bone substance is necessary for the application of this tech- nique. Here, the resorption rate is lower than in cases of vertical augmentation (Esposito2 2009). Thus, the lateralisation of the inferior alveolar nerve facilitates implantation in the lateral man- dibular tooth area. There are two operative approaches cited in literature that suggest how to change the route of the nerve, and how to make implantation possible. This article describes a technique which minimises risks thanks to exact planning and by using Piezo surgery. Surgical techniques In 1987, Jensen8 and Nock were the first to publish this technique developed for the translocation of the mental foramen. The technique shows the exit of the inferior alveolar nerve at the mental foramen. Being ob- served and taking care of the nerve, the foramen is extended Lateralisation of the inferior alveolar nerve Dr Bernd Quantius describes the surgical technique used to minimise probable risks ‘As observed in the mandible, the sur- vival rates of 8mm long implants are similar to the survival rates of longer implants’