Evaluation of Bone Regenerated With Guided Bone Regeneration (GBR) Using Polymethylmethacrylate (PMMA) Membrane

Guided bone regeneration (GBR), is the most widely used technique to facilitate bone generation. It depends on using a biocompatible membrane that acts as physical barrier preventing the connective tissue from invading the bone defect.

To achieve maximum bone regeneration, GBR membrane should have several characteristics, including:

• Biocompatibility.
• Proper stiffness for space maintenance.
• Prevent epithelial cell migration.
• Appropriate resorption time after proper bone regeneration. Membranes used in guided bone regeneration (GBR) may have some limitations as the need of second surgery for removal of the membrane (in case of non-resorbable membranes as titanium mesh or expanded polytetrafluoroethylene (e-PTFE) membranes), lake of space maintenance (as collagen membranes) in addition to their high cost.

Thus, we aim to use a commercially available material as polymethyl methacrylate (PMMA) with (GBR) to facilitate bone generation as well as subsequent implant placement.

Recent forms of (PMMA), have been certified to be biocompatible and safe for skin and mucosal contact. PMMA is characterized by having high toughness which may provide a space maintenance when using as membrane in guided bone regeneration (GBR). The PMMA prosthesis can be pre-fabricated, which results in reduction of surgical time, easy technical handling and good esthetic results.

In addition, it has a relatively low cost when it is compared to other types of membranes used in guided bone regeneration (GBR).

Inclusion criteria

• Patients with edentulous area related to horizontally deficient aesthetic zone of maxilla.
• Patients are physically healthy with no medical history of any systemic or local disease that would contraindicate ridge augmentation and/or implant surgery or complicate the healing process. (Severe liver or kidney disease, a history of head and neck radiotherapy, chemotherapy at the time of surgery, uncontrolled diabetes, active periodontal in the residual dentition, inflammatory or autoimmune disorders of the oral mucosa, poor oral hygiene, patient failure to cooperate, and any other disease condition contraindicating the oral surgery).
• Non-smokers.
• Free from temporomandibular joint disorders and abnormal oral habits such as bruxism.
• The edentulous ridges were covered with optimal thickness of keratinized mucosa with no signs of inflammation, ulceration or scar tissue.
• The occlusion shows sufficient inter-arch space for future prothesis.

Exclusion criteria

• General contraindications to surgery.
• Patients subjected to irradiation in the head and neck area less than 1 year before fixation.
• Untreated periodontitis.
• Poor oral hygiene.
• Uncontrolled diabetes.
• Pregnant or nursing.
• Substance abuse.
• Psychiatric problems or unrealistic expectations.
• Severe bruxism or clenching.
• Immunosuppressed or immunocompromised.
• Treated or under treatment with intravenous amino-bisphosphonates.
• Patients participating in other studies, if the present protocol could not be properly followed