The present invention deals with the initial hydration reaction of highly alkaline chemically bonded ceramic systems such as Ca-aluminate and Ca-silicate, exhibiting a controlled pH development, reduced from very high levels to be in a pH range of 7-9 by the use of an internal buffer system added to the CBC type biomaterial used. The invention is especially intended for endodontic, orthopaedic applications and/or soft tissue applications and/or drug delivery carrier applications.