ROEN0310

28 I I research _ primary teeth endo in the analysis, the teeth were required to have remained in situ for at least 12 months in order to avoid the inclusion of early failures in the baseline studies. AccordingtoEinwag,6 the90to100%clinicalsuc- cessrateofpulpotomiesusingN2Endodonticcement (Ghimas) is the same as that achieved using the five- minute Formocresol technique, which is not surpris- ingowingtotheirsimilarcomposition.PriortotheEU certificationof14June1998,N2contained7%form- aldehyde, which was subsequently reduced to 5%. Bürkle7 reported a low technical sensitivity and good clinical results for all aldehyde-containing ma- terials, such as Formocresol, glutaraldehyde and N2. _Materials and method A prerequisite for treatment was the restorability of the respective teeth. An exclusion criterion was increasedmobilitywithoutadvancedrootresorption. In accordance with these, the following endodontic treatments between 1992 and 1998 were recorded. X-rays were only routinely available for mortal am- putations and root-canal treatments of gangrenous primary teeth. Where possible, follow-up X-rays of the latter were taken. Vital amputations (pulpotomies), mortal amputa- tions and root-canal fillings were performed using theroot-canalfillingmaterialN2underrelativelydry conditions. For the root-canal filling, N2 powder and N2 liquid were mixed to a creamy consistency and applied near the apex following preparation using a manual reamer or mechanical HERO 642 endodontic files (MICRO-MEGA). For vital or mortal amputations, N2 was mixed to a relatively solid consistency. First, deep carious de- fectswereremovedwithanexcavator.Theremaining carieswasexcavatedusingathicksphericalburwith- out water-cooling, followed by cavity preparation with elimination of the coronal pulp using a turbine. Frequently, the remaining pulp bleeds from the canals. Light bleeding can be disregarded, but N2 must be firmly applied to the cavity for several min- utes in the case of heavier bleeding. Owing to the formaldehyde level, the bleeding can be stopped rel- atively quickly. The blood-soaked N2 is then removed fromthecavityandreplacedwithfreshlymixedN2of a solid consistency. Figs. 1–4_11-year-old patient. Treatment of the lower gangrenous second primary molar. Fig. 1_19.06.1992: Ante treatment. Fig. 2_19.06.1992: X-ray control of the incomplete r.c.f. Fig. 3_12.10.1993: Follow-up X-ray after 16 months. Fig. 4_19.06.1992: Fistulation through the gum. roots3_2010 Fig. 1 Fig. 4 Fig. 2 Fig. 3