Physical Properties of Latex and Non-latex Dental Dam Materials

Rubber dam isolation is mandatory in endodontic therapy (Quality guidelines for endodontic treatment, European Society of Endodontology 1994). It is also recommended in adhesive dentistry to ensure that acid-etched surfaces are free from saliva contamination. Traditionally, the dam is made of latex (“rubber dam”). Due to a growing number of allergies to latex (e.g. Rankin 1993, de Andrade 2000), manufacturers have developed non-latex alterntives. So far, scientific information on physical properties of dental dam is limited (Svec 1996); no information is availlable elastic properties of recent non-latex substitutes. Objective: Therefore, the aim of this study was to determine the elastic properties of state-of-the-art latex and non-latex dental dams. Materials: Investigated were 22 dental dams from 7 manufacturers, including 18 latex- and 4 non-latex-materials. Methods: Tear stresses were measured following a new test protocol (ADA WG 90, dumb-bell and angel-piece samples). Coded samples were teared in a universal testing machine (Zwick Roell Zwicky). Tear-strengths were recorded automatically and calculated statistically (Tukey-procedure, alpha set to p<0.05). Results: Compared by the nature of the material, elasticity of latex dams was significantly higher than the same manufacturer´s non-latex dams (Hygenic medium latex dam 14.48 ± 3.25 MPa vs. medium non-latex dam 7.84 ± 1.08 MPa). With regard to the age of latex samples, elasticity of new material (Hygenic medium latex) was significantly higher than 11 and 12 year old material (9,20 ± 1,3 MPa vs. 6,46 ± 0,55 MPa). Between different manufacturers of latex dams, elasticiy differend, depending on the strenght of the am (thin: no differeneces, medium + heavy: significant differences). Conclusions: Future ADA-standards comparable to the methods employed in this study will help dental consumers to evaluate dental dam´s properties in advance. The tested non-latex dams were less elastic than comparable latex material.