guided bone regeneration around immediate implants

Conditions: Missing Tooth

Summary: an important result of healing after tooth extraction is a reduction in dimensions of the remaining bone at that site. this reduction of bone volume precludes successful restoration of the space using a dental implant. bone augmentation has shown promise in clinical reports to reduce this loss of bone volume, thus allowing implant placement and restoration. the purpose of this study is to evaluate the clinical and radiographic outcomes of guided bone regeneration around dental implants placed in fresh extraction sockets.

aim: the purpose of this clinical study is to investigate the effect of a non-resorbable polytetrafluoroethylene (ptfe) membrane on immediate implant placement in the esthetic zone. material and methods: systemically healthy subjects presenting with a hopeless tooth in the maxillary premolar or anterior region will be recruited in the study. following a minimally traumatic tooth extraction, subjects will be randomly distributed into one of two treatment groups, a membrane (test) or a no membrane (control) group. both groups will receive immediate placement of an implant along with placement of a bone graft material to fill the spaces around the implant. sites in the test group will receive a non-resorbable ptfe membrane over the socket, whereas those in the control group will receive a collagen dressing over the socket. at sites in the test group, the membrane will be removed at 4 weeks. a second stage surgery and placement of a provisional restoration will be carried out 4 months after implant placement. final restorations will be placed 3 months after placement of the provisional restoration. clinical and radiographic measurements will be performed at baseline, implant placement, placement of provisional and final restorations and at the 5-month recall visit.

Eligibility criteria:
inclusion criteria: * males and females aged 18 or older. * systemically healthy (american society of anesthesiologists i or ii). * subjects will have one or more anterior or premolar teeth with a hopeless prognosis, with adjacent and opposing teeth present. * compliance with all requirements in the study and signing the informed consent exclusion criteria: * active acute infection at the extraction site (e.g., sinus tract, swelling) * absence of sufficient mesio-distal width to place an implant as per the study protocol. * absence of sufficient bone height to house a 10mm long implant. * the subject lacks a stable occlusion and/or a healthy periodontium. * current smokers or quit smoking less than one year * chronic use of medications known to affect the periodontal status (calcium antagonists, anticonvulsives, immunosuppressives, anti-inflammatory medications) * pregnancy or lactating mothers * current orthodontic or periodontal treatments * history of alcoholism or drug abuse * untreated deep carious lesions or defective restorations that can potentially exacerbate during the course of the study * diseases of the immune system or any medical condition that may influence the outcome (uncontrolled diabetes (hba1c \>7) * bone disorders (hyperparathyroidism, osteoporosis, or paget's disease) * neurologic or psychiatric disorders, systemic infections * a history of iv bisphosphonate use.