Figure 5: Shows the results of the histomorphometrical thickness measurements of the Mucoderm® matrix (A) and the Collprotect® membrane (B). Membrane thickness of the the Mucoderm® matrix (A) was significantly reduced on day 30 compared to day 3 (*P<0.05). Membrane thickness of the Collprotect® membrane (B) was highly significant reduced between day 15 and day 3, between day 30 and day 3, between day 30 and day 10 (***P<0.001) and between day 15 and day 10 (**P<0.01). Decrease of membrane thickness is stated as significant if P-values were less than 0.05 (*P<0.05), and highly significant if P-values were less than 0.01 (**P<0.01) or lee than 0.001 (*** <0.001).