A novel approach to treat peri implantitis with the help of PRF

A new field of biomédical science, known as tissue engineering, applies the principles of biology and engineering to the development of functional substitutes for tissues and organs. Little is known about the influence of Keratinised Mucosa dimension around implants on the soft and hard tissue health The purpose of this case report is to understand the importance of healthy tissue around the implants for long term success and how biomimetic materials like PRF Membrane can be incorporated in treatment plan as an important modality in selected cases.


Introduction
Replacing missing teeth with dental implants has become a popular procedure among patients and clinicians because of the high survival rate and the predictability of the procedure. Long-term follow-up studies have shown that peri-implant complications are common and that implant survival does not necessarily mean a successful implant. Furthermore, studies have shown that 5% to 11% of all dental implants fail and have to be removed [1,2]. When a foreign body is placed in bone or soft tissue, an inflammatory reaction inevitably develops. Hence, osseointegration is but a foreign body response to the implant, which according to classic pathology is a chronic inflammatory response and characterized by bone embedding/separation of the implant from the body. The peri-implant mucositis and peri-implantitis [3]. Peri-implant mucositis is an inflammatory lesion that resides in the soft tissue surrounding a dental implant without signs of bone loss following the initial bone remodeling. In contrast, peri-implantitis also affects the supporting bone, causing progressive bone loss beyond the normal biologic remodeling.
Periodontal implant complications can be biologic, technical and/or esthetic in origin. Prognosis, once disease is already present, will be determined by the ability to restore those characteristics. Diagnosis or "detoxification" of the implant surface followed by resective and/ or bone regenerative procedures to correct the anatomical conditions for improving plaque control and for eliminating the pathologic peri-implant pockets). Although nonsurgical treatments are recommended for mucositis lesions, their use has been proven not to be effective in peri-implantitis lesions [4]. The greatest challenge in clinical research is development of bioactive surgical additives, which help to regulate inflammation and increase the speed of healing process [5]. A new field of biomédical science, known as tissue engineering, applies the principles of biology and engineering to the development of functional substitutes for tissues and organs. The triad that constitutes the base of tissue engineering with a reparative objective is formed by the following: matrices or scaffolds, with various presentations (gels, fibrous matrices, permeable membranes), progenitor cells (undifferentiated stem cells, or cells with preliminary differentiations) and growth factors. After centrifugation, the L-PRF clots were removed from the tubes using sterile tweezers and placed on sterile woven gauze. Clots were emptied from their serum by compressing them between two pieces of woven gauze. L-PRF membranes were prepared by compressing clots between two pieces of woven gauze. In the third quadrant, partial thickness incision was made extending horizontally 2 to 3mm beyond the mesial and distal most implants and the Vertical incisions were extending into the vestibule. Partial thickness flap was raised and the amount of implant exposed was now clearly evident. The contaminated surface of the implant was smoothened off with a fine grid polishing diamond and rubber polisher (implantoplasty) and the surface disinfected with chlorhexidine 0.12% [9] to remove all bacteria deposits, facilitate soft tissue reaccommodation and limit and minimize future plaque deposition that would reinitiate the disease episode. PRF membrane was kept exposed to the oral. In the fourth quadrant, surgery was performed after sufficient healing was seen in third quadrant. PRF membrane was prepared in similar fashion. Sulcular incison was taken and two short vertical releasing incisions were performed. Thereafter a split-thickness mucosal flap was prepared in the vestibule, whose coronal margins were sutured apically with the periosteum. PRF membrane was then placed over the exposed connective tissue bed and secured around the gingival former with stabilizing suture and sling suture respectively ( Figure   4) (vestibuloplasty with PRF membrane). In both the quadrants, on day 1 after the surgery, the surface of the PRF membrane appeared whitish in colour ( slightly more attachment loss than implants with keratinized mucosa. Thus the Keratinised Mucosa thickness and width around dental implants affects both the clinical and the immunological parameters at these sites [10]. According to the recently proposed guidelines for the treatment of peri-implant disease [11], in this case with no bleeding on probing, no pockets, probing depth less than 3mm, no pus discharge and also when the amount of keratinized gingiva is less than 2mm with soft tissue dehesence.
The ideal treatment would be soft tissue grafting procedures.
Basically, two different peri-implant soft tissue augmentation methods can be applied [12]: Fibrin is activated form of fibrinogen present in blood plasma and αgranules of platelets. Soluble fibrinogen is transformed in insoluble polymerized fibrin matrix during hemostasis [13]. The fibrin matrix present in PRF is flexible, elastic, stable and very strong [14]. L-PRF is an optimized blood clot with stronger fibrin architecture and mechanical properties than a natural blood clot or a PRP gel. In comparison of a natural blood clot or a PRP gel, a L-PRF membrane is a solid material easier to handle and to position in the defects and this is also a considerable advantage. While other membranes are considered as foreign bodies by the host tissues and interfere with the natural tissue healing process, a L-PRF membrane is as natural as the host tissue: it is a blood clot prepared in an optimized form.
The property of slow release of growth factors and matrix proteins from the L-PRF membrane promotes 2 specific biological mechanisms during coverage: impregnation and induction [15]. First the surface is impregnated with blood proteins, which are the first biological links between the surface and a new attachment: this is an old validated concept in periodontal surgery [16]. Second, contrarily to PRP gels which gives away immediate release of growth factors, the slow release of molecules from the L-PRF membrane lasts several days [17,18] and thus is long enough to trigger a cell induction phenomenon [19]. The growth factors stimulate cell proliferation, neovessels develop within the fibrin matrix, the periosteum is stimulated, the gingival fibroblasts migrate within the fibrin matrix and slowly remodel it, while the membrane guides surface epithelialization if needed: this matrix offers a new scheme of development to the natural tissue. The short term result is a quick wound closure and healing [20], with the reduction of postsurgical pain and edema. The long term result is not only a stable covering, but also a thicker stable gingiva.

Conclusion
The use of PRF in implant applications is in its infancy.

Competing interests
The authors declare no competing interest.

Authors' contributions
All the authors have read and agreed to the final manuscript.