Abstract The purpose of this study was to investigate the effectiveness of two dentin bonding systems, one of which was also in combination with a self-curing resin, when ap- plied in V-shaped circular cavities cut in anterior teeth crossing the cementum–enamel junction. Twenty-seven teeth scheduled for extraction for periodontal reasons were treated in vivo. The sample teeth were divided at random into three groups. Group 1 was treated with All Bond 2 (AB2) +Z-100 composite, group 2 with Scotchbond Mul- tipurpose Plus (SMPP) +Z-100, and group 3 with AB2 in conjunction with Bisfil 2B as liner and Z-100. The in vivo restored teeth were extracted after 2–3 months of clinical service. They were then immersed in a dye solution for 24 h, sectioned, and scored for marginal leakage. Analy- sis of variance revealed no significant differences between the three groups both at cervical and incisal sites. The en- amel sites were free from any leakage. Only two cervical sites of groups 1 and 2 and one of group 3 showed a score 1 for leakage. The results of the short-term clinical perfor- mance of the three systems were promising. Key words Leakage · Class V · Adhesive systems · Bonding · In vivo evaluation · Resin composite Introduction Microscopic gaps at margins can permit bacterial or toxin invasion, marginal staining, secondary caries, and pulp in- flammation [1, 2]. Thus, leakage tests have been and are still frequently used in the laboratory in an attemp uate the effectiveness of bonding restorative syste 4]. Recently, in vivo assessments of dentin bonding have been published [5–7]. Nakabayashi et al. [8, Gwinnett and Kanca [7] have investigated, by electron microscopy and transmission electron copy, the hybrid layer formation between resin an in vivo. Barnes et al. [10] and Ferrari et al. [11, 12 ported leakage studies performed in vivo after several dentin bonding systems directly on class V ties. The anatomic, pathologic, and physiologic varia dental substrates [13–15], the characteristics of t bonding system [16], the restoring technique [17] properties of resin composite material [17] are all able to affect directly the marginal sealing ability tal etch wet technique seems to be the more effec obtaining an adequate enamel etching without too sive a demineralization of dentin [18]. A self-curin torative resin has been developed for directed shr and its use has been proposed in combination wit generation enamel–dentin bonding system [19]. The purpose of this study was to investigate tw bonding systems, one of which was also used in co tion with a self-curing resin, comparing in vivo lea data for restorations which had been in servic months. Materials and methods Twenty-seven volunteer patients, each with one severely p tally compromised anterior tooth, were selected. The twenty- seven teeth selected for this study had not received previo rative treatments and were scheduled for extraction. The p possible discomforts, or risks were explained fully to the h jects involved, and their informed consent was obtained pr investigation. All the selected teeth tested were vital. Circular, V-shaped cavities with a diameter of 3 mm and imum depth of approximately 2 mm were cut under copiou spray with a diamond point bur mounted in a turbine hand Clin Oral Invest (1997) 1: 61–64 © Springer-Verlag 199 Marco Ferrari · Francesco Mannocci Maria Crysanti Cagidiaco · Gerard Kugel Short-term assessment of leakage of class V composite restorations placed in vivo ORIGINAL ARTICLE M. Ferrari ( ½ ) · F. Mannocci · M. C. Cagidiaco Research Center for Dentistry, Piazza Attias 19, I-57125 Livorno, Italy Tel.: +39-586-892283; Fax: +39-586-898305 M. Ferrari · F. Mannocci · M. C. Cagidiaco Dental School, University of Siena, Siena, Italy M. Ferrari · G. Kugel Gavel Center for Restorative Dental Research, Tufts University, Boston, Mass., USA