[Tunnel preparations. Traditional and alternative methods].

Alternative, conservative techniques for treatment of initial approximal carious lesions in the premolar-molar region are described. Beside the "traditional" tunnel preparation a modified technique is described, in which the proximal enamel wall is left untouched, unless the carious lesion has perforated the amelodentinal junction. The internal Class I-cavity is filled with a radiopaque glass ionomer cement and a composite resin. During 2 years 282 approximal surfaces have been treated and in the 1-year follow-up study is shown that both techniques have sufficient success rate to encourage further use and study. The advantages of these techniques compared to Class II-restorations with amalgam or composite resins are discussed and judged as considerable.