“…3. Addition of a radiopaque substance and/or an antibiotic was reported not to interfere with the mechanical strength of the cement (Hessert 1971;Marks et al 1975). This, however, was refuted by Grünert and Ritter (1974), de Wijn et al (1975b and Haas et al (1975), who demonstrated that these additions cause mechanical weakening of the cement due to loss of homogeneity and increased water absorption.…”