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Vertical Ridge Augmentation (VRA) around Dental Implants with the Use of a Dense PTFE Membrane, to Correct Previously Failed Augmentations.

INTRODUCTION
Vertical ridge augmentation (VRA) is one of the most challenging procedures. This is the first case report to show 2-5 mm VRA after two unsuccessful GBRs around previously placed dental implants, with the use of an exposed d-PTFE membrane.


CASE PRESENTATION
A 79-year-old ASA II Caucasian male presented after two previous GBR procedures on the LLQ. The second attempt left the site with two exposed implants, scar tissue, no keratinized tissue and lack of vestibular depth. VRA was attempted with the use of cortical perforations, tenting screws, dense PTFE membrane and a 50:50 mixture of anorganic bovine bone matrix and mineralized allograft. The site was left to heal in a secondary intention, leaving the d-PTFE membrane exposed. The membrane was removed in 4 weeks post-operatively. The healing abutments were placed, the tenting screws were removed, and the site was allowed to heal for more than seven months. Radiographically, VRA was achieved ranging from 2-5mm. A vestibuloplasty was performed using a diode laser and subsequent flap dissection. Four months after the vestibuloplasty, the tissue surrounding the implants showed adequate keratinization, and an elongated vestibular depth. In addition, in both implants the emergence profile buccal and lingual was more than 3 mm and the patient was referred to his prosthodontist for the fabrication of the final restorations.


CONCLUSIONS
VRA around dental implants was achieved with the use of a non-resorbable dense PTFE membrane, which was left exposed to heal in a secondary intention, tenting screws and a combination grafting technique to correct two previously failed GBRs. This article is protected by copyright. All rights reserved.