AIM
Platelet-rich plasma (PRP) is blood plasma whose rationale is that platelets release different substances promoting tissue repair and affect the behavior of other cells and modulate inflammation and angiogenesis. Platelets, in fact, play a fundamental role in mediating the healing of damaged tissue thanks to their ability to release growth factors, such as PDGF, TGF ß, VEGF, IGF-1, FGF, and EGF.
Therefore, PRP can be used in those surgical areas where a faster tissue regeneration is required.
The aim of this work is to stimulate the physiological mechanisms of tissue regeneration, bone regeneration in particular, increasing their concentration in the implant sites.
METHODS
In the present work, nine male patients aged between 28 and 55 years and two females patients were treated.
They presented with several problems: three of them with radicular cystic lesions, unscrewed prosthesis, destruction of the bone saddle due to a periodontal disease and severe atrophy of the jaw.
After objective structured clinical examination and radiological and periodontal examinations, PRP in combination with small amounts of autologous bone was used to solve these problems.
It was obtained with a double-centrifugation technique, characterized by the decrease of platelet stressors according to the shortness of centrifugation time and the level of revolutions applied.
After adding PRP in the implant site, an acceleration of the mechanisms of tissue regeneration was obtained; then, the implant was placed.
RESULTS In the 11 cases who had received grafting of deantigenated, demineralized bovine bone called Geistlich Bio-Oss ® (mixed with 50% of cortical and medullary grafts and 50% of pure-phase beta-tricalcium phosphate) and Sint Oss made by “Industrie Biomediche e Farmaceutiche” with the addition of growth factors of PRP, we noticed a rapid regeneration and bone maturation and, consequently, a better quality at 6 months (phase II or lamellar bone), with a greater amount of bone trabeculae and greater density of the regenerated bone tissue.
The resulting data were analyzed through various methods: Histological and histomorphometric examination of specimens at 6 months showed an extension of bone trabeculae of 7 4 ± 11 % for the grafted bone enriched with PRP, compared with 55.1 ± 8% of specimens with bone grafts ( the extent of the native bone was 38 , 9 ± 6 %); Immunocytochemistry with monoclonal antibodies targeting growth factors PDGF and TGF – ß confirmed their presence in platelets of PRP and in several cells of bone tissue taken for grafting;
CONCLUSION
In conclusion, we can say that the action facilitating the neo-osteogenesis of PRP is achieved through the increased concentration, during surgery, of platelet-derived growth factors and other blood proteins, thanks to the increase of chemotaxis of competent cells involved in the processes of angiogenesis, stimulation of mesenchymal cells, proliferation of preosteoblasts and their differentiation into osteoblasts , i.e. the whole physiological mechanism of tissue regeneration .
The faster maturation and the increased quantity of regenerated bone tissue, as well as the improved re-epithelialization of the wound, are the key points of techniques using PRP.
PRP gel, being autologous, has no characteristics of toxicity and immunogenicity even when alloplastic materials with osteoconductive properties are added because one is running out of autologous bone.
The protocol allows to quickly obtain valid results both in minor and advanced oral surgery, with a small sampling of peripheral venous blood under sterile conditions appropriate to the dental operating room, with simple and inexpensive equipment, without loss of time and without additional discomfort for the patient.
Authors: INCHINGOLO Francesco, PUGLIESE Adalisa, MARRELLI Massimo, TATULLO Marco, INCHINGOLO Angelo Michele, POLI Gaetano,INCHINGOLO Alessio Danilo, SCHINCO Fabio, MARINELLI Grazia, CERRUTI QUARA Piero, MUOLLO Ferdinando, RESTA Gianpiero, SERAFINI Maurizio, DIPALMA Gianna.