**3. Conclusion**

42 Biomaterials – Physics and Chemistry

Fig. 20. Auricular epithesis.

Fig. 21. Preoperative frontal view of the patient.

The facial prosthetic rehabilitation is a valid alternative when the conventional reconstructive surgical techniques cannot be applied either because of the psychophysical conditions of the patient or because of an excessive substance loss. The surgical technique with prosthesis has several applications: malformative, infective, traumatic pathology, results of oncologic surgery and radiant therapy, and particular clinical conditions such as diabetes, leukemia, and others. The position of epithesis, as described in the literature5,6 and confirmed by the experience of our epithesis Center, is suitable in selected cases:


The described technique presents absolute limits such as osteolitic process, leukemialymphoma, and terminal cirrhosis and relative limits such as ending life, hygienic deficiency, and psychological refuse. Another important limit is the radiotherapy treatment; the skeletal structure of persons who undergone radiotherapy react to the osteointegration process with a lower success percent. It goes, in fact, to consider that if the combined application of the chemotherapy and radiotherapy treatments with demolitive surgery increases the life on average, the survival of the subject with surgical cancerYablation increases, compromising the quality of life.7 The results of the osteointegration in patients who have underwent chemotherapy are very variable, approximately 60% and 100%.8 In accordance with the literature, we can affirm that the radiotherapy compromises the human tissues, hindering the osteointegration process, when the irradiation is around 5000 Gy. Besides the site and the radiation dose, the time existing between the radiant treatment and the positioning of the implant is another determinant factor for the success of osteointegration process. In particular, 6 months should exist between the term of the radiant treatment and the positioning of the implant period in which the tissue alteration produced by the radiations are in regression. According to the oncologic guideline, it would

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be more opportune to wait 1 year to avoid the recidivism risk.8 Furthermore, the treatment in the hyperbaric room is effective in the bone life, with higher success percents.8,9 Another fundamental aspect is the epithesis stability,which depends frommany circumstances such as hygienic condition, material quality, and the correctmethod of the epithesis production;when these conditions are respected, the epithesis can resist for 2 years. The application of an epithesis happens with no invasive and immediate results, both fromthe aesthetic and psychologic point of views, allowing to get around with the heavy social insertion problems derived from his facial deformation. The therapeutic iter in the reconstructive treatment with epithesis foresees a dynamic study with few fundamental stages:


Beyond the application of bone implants, several retentionmethods are possible: anatomic, exploiting the premade cavity getting to the deficit (ocular epithesis), andmechanical, exploiting outside anchorage strengths (sight glasses) and adhesive, by glue.10 Thanks to the use of the bone implants, it has been able to get around the problems caused by the use of adhesives like decoloration, the precocious deterioration of the epithesis, and inflammatory phenomena of the skin in contact with epithesis' materials. Under the point of view of the aesthetic result, the margins of an epithesis can be easily hidden, and the prosthesis ismore stable, is easy to wear, and keeps under a hygienic point of view. Furthermore, the psychologic appearance should not be neglected because, unlike traditional prosthesis, the epithesis fixed with implants are not considered as an extraneous object, with the consequent improvement of a good quality of life. At present, our experience teaches us that the indication to the position of epithesis as the first choice of treatment is when the conventional reconstructive interventions turn out to be inapplicable or ineffective
