Study on Regenerative Treatment of Intra-bony Defects

Inclusion Criteria: * Males and females aged between 18 and 70 years. * Presence of at least one 1- or 2-wall intrabony periodontal defect. * Defect width at least 2 mm. * Defect depth at least 4 mm. * Defect located at a single rooted tooth or at the approximal site of a multi-rooted tooth if the tooth is not affected by a furcation involvement. * Written informed consent. * Subject must be judged healthy by the investigator at the time of surgery. * Subjects must have had a plaque index \< 0.8 at the end of the initial periodontal therapy. Exclusion Criteria: * Medical conditions required prolonged use of steroids. * Standard blood tests performed by the medical practitioner showing leukocyte dysfunction and deficiencies. * History of haemophilia, bleeding disorders, or cumarin therapy. * History of neoplastic disease requiring the use of chemotherapy. * History of radiation therapy of the head and neck. * History of renal failure or chronic renal diseases. * Chronic liver diseases. * Severe or uncontrolled metabolic bone disorders. * Uncontrolled endocrine disorders (including diabetes). * Current pregnancy at the time of recruitment. * Physical handicaps that would interfere with the ability to perform adequate oral hygiene. * Use of any investigational drug or device within the 90 day period prior to surgery on study day 0. * Alcoholism or chronical drug abuse. * Immuno-compromised patients (including HIV). * Smokers (occasional smoking is allowed). * Conditions or circumstances , in the opinion of the investigator, that could represent a general contra-indication for surgical procedures or would prevent completion of study participation or interfere with analysis of study results, such as a history of non-compliance, or unreliability. * Local inflammation. * Mucosal diseases (e.g. erosive lichen planus). * History of local radiation therapy. * Presence of oral lesions (e.g. ulceration, malignancy). * Inadequate oral hygiene or patient who is unmotivated for home care. * Teeth with untreated endodontic or cariologic problems. * Defects that during surgery show deviation from the inclusion criteria.