Uso do hormônio de crescimento humano recombinante (rhGH) tópico na osseointegração em implantes dentais : uma revisão sistemática e metanálise

Abstract

The recombinant human growth hormone (rhGH) has been studied and shown to be a promising ally in bone regeneration. Its effect is given by stimulating osteoprogenitor cells, accelerating bone repair, especially in the initial stages of healing. The first article of this Thesis was a Systematic Review of studies in animal models evaluating the effect of topical use of rhGH after the insertion of dental implants. An extensive search in the PubMed, Embase, Cochrane - Central and Scopus databases was conducted by two independent reviewers. After the screening and eligibility phases, six studies were eligible, of which four entered for quantitative data synthesis. The aggregate results showed a significant effect on the average percentage of contact area between bone and implant [14.22% - 95% confidence interval (95% CI) (5.9; 22.5), which decreased over time [2 weeks: 20.11 % CI95% (6.76; 33.46); 6 weeks: 8% 95% CI (5.23; 10.77); 8 weeks 3.14% (1.25; 7.53)]. These results point to a promising effect of topical rhGH, with its clinical relevance to be confirmed by randomized clinical trials. The second study evaluated the opinions of 52 Dental Surgeons (DS). The main focus was on decision making regarding the ideal implant insertion period, after maxillary sinus lift. Previously to the application of the questionnaires, three patients received bilateral sinus lift with lyophilized bovine bone (Bio-Oss), associated or not with topical application of rhGH (split mouth model, with randomization for rhGH groups). After 3-5 months, cone-beam tomography (CT) was performed and added to the questionnaire, in order to verify, in a blind way, the influence of the use of rhGH in the decision making of the DS, based on the bone quality of the region. The main question was: "Based on this CT image, do you think that the site where the maxillary sinus lift was carried out is ready for the implant installation now?" Yes/No. The results showed a greater agreement between the decision to perform the implantation in the sites with the use of rhGH (90%, 84.6% and 63% of the “yes” answers for the sites with rhGH application) and not to perform it in the sites without rhGH (52%, 53% and 64% for “no”). Based on these findings, the use of rhGH in breast-lifting procedures seems to influence decision making as to when to insert the implants, with a tendency to shorten the waiting period between both procedures.