Maxillary sinus augmentation using different grafting materials and dental implants in monkeys. Evaluation of autogenous bone combined with porous hydroxyapatite.

Abstract

The aim of this study was to evaluate clinically, histologically, and histometrically the use of autogenous bone combined with porous hydroxyapatite (Interpore 200) as a grafting material for maxillary sinus augmentation procedures. In 4 adult male rhesus monkeys (Macaca mulatta) the 1st, 2nd and 3rd maxillary molars on one side of the jaws were extracted. After a healing period of 3 months, maxillary sinus augmentation procedures were performed in each monkey, and the sinuses were grafted with autogenous bone from the monkeys' tibia mixed in a 3:1 ratio with porous hydroxyapatite. At the same time, 2 pure titanium plasma-sprayed IMZ cylinder implants were immediately placed into the augmented sinuses (i.e. simultaneous implants-loaded group). After 4 months, 2 additional similar implants were placed into the previously augmented sinuses (i.e. delayed implants-loaded group). Four months later, the abutment connection was performed and all 4 implants were loaded with a gold-alloy bridge for 6 months (i.e. until sacrifice of the animals). The contralateral side of each monkey received similar treatment with the exception that the extractions were performed 7 months after those in the opposite side and that the implants were not loaded. Thus, 2 additional study groups (i.e. simultaneous implants unloaded group and delayed implants unloaded group) were obtained. Clinically, all loaded implants were stable at the day of sacrifice. Histologically, the grafted sinuses exhibited a significant amount of new bone formation. The porous hydroxyapatite granules appeared integrated with the newly formed bone. Histometric analyses revealed that delayed implant placement resulted in a greater amount of direct mineralized bone-to-implant contact in the augmented area than the simultaneous implant placement. Furthermore, the percentage of direct mineralized bone-to-implant contact was far more significant in the residual bone than in the augmented area. It was concluded that the autogenous bone/porous hydroxyapatite graft combination enhanced bone formation and mineralized bone-to-implant contact in the augmented sinuses and that the delayed implant placement may be favorable for sinus augmentation procedures.

Histomorphometric assessment of bone formation in sinus augmentation utilizing a combination of autogenous and hydroxyapatite/biphasic tricalcium phosphate graft materials: at 6 and 9 months in humans

“…These findings were repeatedly confirmed by research groups in animal (Hü rzeler et al 1997) and human (Watzek et al 1998;Boëck-Neto et al 2002;Hallman & Zetterqvist 2004;Artzi et al 2005;Peleg et al 2006) clinical trials. Furthermore, this composite combination has shown its efficacy in lateral augmentation of the alveolar ridge (Hellem et al 2003) and has been tested in a critical-size defect in goats (Merkx et al 2000).…”

Clinical evaluations of OSTEON® as a new alloplastic material in sinus bone grafting and its effect on bone healing

“…Using 1:1 mixture of xenograft (Bio‐Oss®) and allograft (Interpore 200®), 1:3 mixture of autogenous bone from iliac crest and Interpore 200®, and 1:1 mixture of autogenous bone from mandibular chin bone and Interpore 200®, Hurzeler et al21 grafted these materials in 133 patients followed by either immediate implant placements (235 implants) or delayed implant placements (105 implants). At 5 years after installing the metal ceramic prosthesis, only four implants failed, and the success rate was 98.8% for this study.…”

Sinus floor elevation using osteotomes or piezoelectric surgery

“…Autogenous bone in combination with Bio-Oss 1 was used in the present investigation to increase success and predictability with Bio-Oss 1 , as reported in the literature 6,16,22 .…”