Periosteal Inhibition Technique for Ridge Preservation A Prospective Study

Socket preservation procedures have been shown to significantly reduce the loss of ridge dimension of an extraction socket. These procedures involve filling the empty socket with a bone graft material, which, serves as scaffold to limit horizontal and vertical ridge alterations. In order to contain the graft material, an occlusive barrier such as an autogenous soft tissue graft, resorbable or non-resorbable membrane, is often required. As yet, no one socket preservation technique has been proven superior to another, and none have proven totally effective in preserving ridge morphology. A net reduction of 1.5 mm in ridge width and 0.5 mm in ridge height is often observed after socket preservation procedures, which may necessitate additional hard or soft tissue augmentation to fully restore the ridge dimension.

In an animal histologic study in 2005, Araujo and Lindhe demonstrated that trauma and loss of periodontal ligament triggered an osteoclastic activity causing loss of bundle bone and modeling of the cortical bone plate. Osteoclasts are multi-nucleated cells that are responsible for bone resorption and are found on the outer layer of bone, beneath the periosteum. Osteoclasts are thought to be derived from pluripotent hematopoietic stem cells. When stimulated, these mononuclear precursors, the smallest of which is 9.5 microns in diameter, proliferate and attach to the bone surface to be resorbed, and only then fuse to form large mature multinucleated osteoclasts.

High-density polytetrafluoroethylene (d-ptfe) membranes have been used in socket preservation procedures as an occlusive barrier to contain the bone graft material.Polytetrafluoroethylene, a stable polymer and highly biocompatible, has a membrane porosity of less than 0.3 microns. It is impervious to bacteria and thus is recommended for a socket preservation technique, where a membrane is intentionally exposed.

In the present study, a high-density polytetrafluoroethylene (d-ptfe) membrane is placed between the periosteum and the buccal bone plate of an extraction socket where it will stay for a duration of 4 months, the time needed for the completion of bone forming within the socket. The goal of the non-resorbable d-ptfe membrane is to prevent the migration of precursor cells to the bone surface and thus their fusion to form osteoclast. The authors hypothesize that the passage of the precursor cells from the periosteum to the bone surface is inhibited by the small-diameter pores in the non-resorbable d-ptfe membrane. Osteolytic activity on the outer surface of the socket is thereby prevented as the precursor cells cannot form osteoclasts. The author coins the term "Periosteal Inhibition technique" for this socket preservation procedure.The study will compare dimension changes between extraction socket treated using the Periosteal Inhibition technique and those allowed to heal without a socket preservation procedure.

Inclusion criteria

• At least 22 years of age
• Systemically healthy
• An extraction of one non-salvageable molar or premolar tooth is indicated. Adjacent teeth must be present to support the measuring template.
• Demonstrated ability to maintain goodoral hygiene
• Willingness and ability to commit to follow-up
• Able to understand study procedure and provide signed informed consent.

Exclusion criteria

• Extensive damaged buccal or lingual bone plate
• Extreme alveolar ridge atrophy
• Extensive vertical bone loss
• Active infection at the extraction site
• Uncontrolled periodontal disease.
• Recent febrile illness (within 6 months) that precludes or delays participation
• Severe renal or liver diseases
• History of radiotherapy of the head and neck region
• Chemotherapy for treatment of malignant tumors at the time of the study.
• Immuno-compromised patients
• Patients on IV bisphosphonates or on long term oral bisphosphonates for more than 3 years.
• Use of disallowed concomitant medications.
• Pregnancy or intending to conceive during the course of the Study.