Porous titanium granules in critical size defects of rabbit tibia with or without membranes

• Published in: International journal of oral science Vol. 6; no. 2; pp. 105 - 110
• Main Authors: Delgado-Ruiz, Rafael Arcesio, Calvo-Guirado, Jose Luis, Abboud, Marcus, Ramirez-Fernández, Maria Piedad, Maté-Sánchez, Jose Eduardo, Negri, Bruno, Won, Alex, Romanos, Georgios
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-06-2014; Springer Nature B.V; Department of Prosthodontics and Digital Technology, School of Dental Medicine, Stony Brook University, Stony Brook, USA%Department of Prosthodontics and Digital Technology, School of Medicine and Dentistry, Murcia University, Murcia, Spain; Nature Publishing Group
• Subjects: Animals; Dentistry; Male; Medicine; Membranes, Artificial; Oral and Maxillofacial Surgery; Original; original-article; Orthopedics; Rabbits; Surgical Orthopedics; Tibia - abnormalities; Titanium - chemistry; critical size defects; bone substitutes; histomorphometry; collagen membranes; titanium granules; membranes; critical; size; substitutes; titanium; defects; granules; collagen; bone
• ISSN: 1674-2818; 2049-3169
• DOI: 10.1038/ijos.2014.6

Recently, porous titanium granules (PTGs) have been indicated for the preservation of the dimensions of post-extraction sockets, as a filler in sinus lift procedures and for the treatment of peri-implant and periodontal defects, based on the osteoconductivity and dimensional stability of the titanium granules. However, there is a lack of information regarding the use of this material in larger defects and in conjunction with membranes. The objective of this study is to test the behavior of PTGs used to fill critical size defects in rabbit tibiae, with and without membranes. Critical defects were created in both tibiae of rabbits, divided randomly into three groups: Group A (defect filled with PTG), Group B (defect filled with PTG+collagen membrane) and a control group (empty defect). After six weeks, histomorphometric analysis was performed. The results showed more defect closures at the cortical area (87.37%±2.2%) and more bone formation at the marrow area (57.6%±1.3%) in Group B, in comparison with the other groups (
P
<0.05); the use of membranes improved the material stability expressed as more percentages of the original material when membranes were used (
P
<0.05). Finally, inflammatory reactions were observed when the granules were not protected by membranes. In spite of the limitations of this animal study, it may be concluded that PTG particles are osteoconductive and allow bone growth. The PTG particles must be covered by a membrane, especially when grafting larger defects, in order to control particle migration, promote clot stabilization and separate the PTG graft from undesired soft tissue cells.
Bone repair: Filling the gaps with porous titanium
Porous titanium granules (PTGs) that support growth of new bone could provide a robust scaffold for dental and skeletal repair. As a truly natural replacement, a patient’s own bone tissue seems ideal for such procedures, but bone implants tend to degrade so artificial materials may be more desirable for some applications. PTGs are sturdy and allow colonization by bone cells. Researchers led by Rafael Delgado-Ruiz of Stony Brook University in the USA tested the capacity of PTGs to mediate bone repair in rabbits. Six weeks after implantation, animals that received implants showed closure of bone defects and extensive growth of new bone relative to controls. Recovery was greatly improved by enclosure of the PTGs within a membrane. Unenclosed PTGs tended to exit the bone defect, leading to incomplete repair and an inflammatory response.