Treatment of periodontal disease with guided tissue regeneration technique using a hydroxyapatite and polycaprolactone membrane

ABSTRACT The aim of this study was to evaluate the use of a malleable membrane composed of hydroxyapatite (60%) and polycaprolactone (40%) as treatment of periodontal disease experimentally induced in dogs. A bone defect of standardized dimensions was created between the roots of the third and fourth premolar of 12 dogs for periodontal disease induction. Six dogs had the defect covered by the membrane and six dogs received only standard treatment for periodontal disease, also applied to dogs in the treated group. The animals were clinically monitored during the experiment. Radiographs were taken after surgery and at 60 days after treatment initiation. Clinical attachment level was also assessed in those moments. On the 60th day, dental sample of all animals, containing tooth, defect and periodontal tissues, were harvested, fixed in formalin and analyzed by microtomography and histology. During the experimental period, the animals showed no pain and purulent discharge, however, there was dehiscence in 50% of animals and membrane exposure in five out of six animals in the treated group. Clinical attachment level showed no difference between groups. Radiographs showed radiopacity equal to the alveolar bone in both groups. The microtomography revealed that the control group had higher bone volume in the defect compared to the treated group; however, the furcation was not filled by new alveolar bone in any animal. Histological analysis revealed that junctional epithelium invasion was lighter in the control group. New bone was only observed in the apical edge of the defect in both groups. Although the composite is biocompatible and able to keep the space of the defect, it did not promote periodontal tissue regeneration within 60 days of observation

Hydroxyapatite, polycaprolactone and alendronate composites for bone regeneration in rabbits' olecranon: histological features

O presente trabalho teve como objetivo avaliar a biocompatibilidade e a osseointegração de compósitos de hidroxiapatita (HA), policaprolactona (PCL) e alendronato (ALN) em defeitos ósseos produzidos no olécrano de coelhos. Trinta e seis coelhos foram distribuídos em quatro grupos, recebendo como tratamento: (1) compósito de HA (49,5%), PCL (49,5%) e ALN (1%); (2) HA (50%) e PCL (50%); (3) PCL (100%); e (4) solução salina 0,9%. As amostras para análise histológica foram coletadas de três animais de cada grupo aos oito, 45 e 90 dias de pós-operatório. No oitavo dia, as bordas do defeito ainda eram identificáveis em todos os grupos. Tecido ósseo novo era formado em contato com o biomaterial apenas nas formulações que incluíam HA. Essas características continuaram evidentes nos outros momentos analisados, embora o defeito estivesse preenchido pelo tecido regenerado. A presença dos biomateriais foi verificada nos três momentos em todos os grupos. Não houve evidências de reação indesejável ao biomaterial. As análises histológicas e histomorfométricas mostraram que os biomateriais são biocompatíveis e aqueles contendo a hidroxiapatita favoreceram a formação óssea no início do processo de regeneração, embora o alendronato não tenha apresentado qualquer efeito

A new surgical technique to treat corneal perforations using amniotic membrane and surgical adhesive

The objectives of this study were to compare surgical techniques and the effects of using n-butyl 2-cyanoacrylate and bovine amniotic membrane to repair perforated lesions in corneas. Penetrating keratoplasty was performed in sixty New Zealand White rabbits under general anesthesia. Group 1 (G1) was treated with n-butyl 2-cyanoacrylate, group 2 (G2) received a fragment of amniotic membrane through the anterior chamber and application of n-butyl 2-cyanoacrylate over the lesion, group 3 (G3) was treated with the same technique as G2 with the addition of an amniotic membrane bandage covering the cornea and sutured in the limbus region, and group 4 (G4) was treated with an amniotic membrane sutured to the lesion and an amniotic membrane bandage sutured in the limbus region. Clinical, histological and histomorphometric examinations of the corneas were performed. The membrane acted as a barrier for aqueous humor in G2 and G3, thereby keeping the surface dry for adhesive application; it also prevented the adhesive from contacting intraocular structures. The groups treated with amniotic membrane and surgical adhesive showed better results than the groups treated with either material alone. Thus, the combination of the membrane with the adhesive is recommended for this type of lesion