implants - internationalmagazine of oral implantology

I clinical study _ flapless implant surgery 08 I implants4_2011 Apositivebleedingscore(BOP)wasfoundat106 of the 346 implant sites (30.63%). A significant dif- ference was documented between Straumann im- plants, where bleeding occurred only in 14.9%, and Thommenimplants,whereapositivebleedingscore was found in 38.2%. No differences between the three implant types werefoundintermsofprobingdepth(PD).Themean PD was 2.4 mm irrespective of the implant design. Bleeding score was significantly higher for those implantswithoutkeratinisedmucosa.OftheStrau- mann implants, 161 were surrounded by a band of keratinised tissue, as were 74 Thommen implants. Only 38 Straumann (26.4%) and 22 Thommen (30.6%) implants showed positive BOP. Eight of the nine Z-Systems implants were placed in keratinised mucosa and none of them showed any signs of in- flammation. Conclusionsandclinicalimplications The results presented in this article demonstrate that healthy peri-implant soft tissue can be ob- tained following minimally invasive surgery and transgingivallyplacedimplants.Flaplessimplantin- sertionshowsasuccessratecomparabletoconven- tional implant surgery. The results of this study prove that flapless implant surgery is a predictable procedure.Inaddition,ourfindingsleadtothecon- clusion that a band of keratinised gingival tissue around implants minimises soft-tissue bleeding. _Introduction Inconventionalimplantsurgery,moreorlessex- tensiveflapsarecreatedtoexposethesurgicalfield. Sincethebeginningsofimplantology,thetechnique hasbeengraduallymodifiedandrefinedtotheone- or two-stage procedures most frequently used to- day. Despite these modifications, the surgical process has remained remarkably constant. After exposure of the jaw bone by preparing a mucope- riostealflap,theimplantisinsertedintoacavitycre- ated by careful bone drilling. Thereafter, the cover- ing soft tissue is sutured to its previous place (Adell etal. 1985). Initial bone loss seems to be caused by inter- ruptedbloodsupplythatfollowsremovalofthepe- riosteum (Ramfjord & Costich 1968; Wood et al. 1972; Kleinheinz et al. 2005). Flapless procedures utilise only a small soft-tissue punch to expose the alveolar crest (Fig. 1). The size of the surgical field corresponds therefore to the implant diameter. The term “minimally invasive” or “flapless” im- plant surgery describes an alternative procedure to conventional incision and flap preparation (Figs. 2–4; Sclar 2007). In addition, this atraumatic ap- proach allows good preservation of the anatomi- cally important gingival and periodontal structures (Al-Ansari & Morris 1998; Zetz & Quereshy 2000; Kan et al. 2000). Flapless surgery is becoming in- creasingly popular and patient acceptance of this procedure is very high. The limited surgical trauma minimises: (a) intra-operative bleeding; (b) surgical time;(c)riskofinfection;and(d)post-surgicalcom- plaints such as swelling and pain related to the sur- gical trauma. In many cases, second-stage surgery, i.e.measurestoexposetheimplantshoulder,canbe avoided (Stoll 2008). Flapless surgery may help to avoid significant bone loss. The tissue punch used has a diameter similar to that of the inserted im- plant. Animal studies have demonstrated the im- portance of the punch diameter. A punch diameter that is minimally smaller than the implant diameter had a positive effect on healing (Lee etal. 2009). It is well known that conventional surgical pro- ceduresusingtitaniumscrewimplantsresultinvery successful long-term survival rates of 94 to 99% (Adelletal.1985;Behnekeetal.2000;Cochranetal. 2002; Roos-Jansaker et al. 2006). This longitudinal study aimed to determine whether flapless, i.e. transgingival, minimally invasive, implant place- ment can lead to a success rate comparable to con- Fig. 3_Flapless implant insertion. Fig. 4_Immediately after implant insertion. Fig. 3 Fig. 4