Comparison of alloplastic implants for facial bones by scintigraphy and histology: an experimental study

Abstract

Reconstruction of bone defects and contour irregularities in the craniofacial region is difficult and often requires complex solutions. This study investigated the tissue response, vascularization and bone ingrowth, in hydroxyapatite, porous polyethylene and silicone elastomer when used as bone graft substitutes. 24 albino rabbits (8 rabbits for each implant) were used in this investigation. Hydroxyapatite 500 particles, silicone rubber and porous high-density polyethylene were placed in the cavities formed with a drill in the rabbit frontal bones. As a part of a prospective study the vascularization rates of all implant materials were analyzed 10 days and 2 months after surgery using 99m Technetium-MDP (Methylene diphosphonate) scintigraphy of the skull. The scintigraphic studies were performed 2 hours after intravenous injection of 4 mCi (148 MBq) 99m Tc-MDP. The frontal bone was excised on the 10th and 60th days. All tissue specimens were placed first in 10% formalin and then in 10% nitric acid solution for decalcification. The vascularization, connective tissue ingrowth, foreign body reaction and bone regeneration around the implant were evaluated. Results of this study suggested that hydroxyapatite and porous polyethylene were stabilized in bone while as expected silicone was mobile, also hydroxyapatite implants are vascularized better and are more biocompatible than porous polyethylene.

Maxillary sinus floor grafting with β‐tricalcium phosphate in humans: density and microarchitecture of the newly formed bone

“…The availability of suitable biomaterials to be used as a bone replacement that facilitates the bone regeneration would eliminate the need for an extra surgical site. Various grafts have been used for this purpose, including allogenic bone, alloplastic bone substitutes and their combinations (Moy et al 1993;Aygit et al 1999;Hanish et al 1999;Tadjoedin et al 2000;Yildirim et al 2000). The effects of these bonereplacing materials have been extensively studied in animal models (McAllister et al 1999;Liu et al 2000;Haas et al 2002;Suba et al 2004) and in vitro experiments (Laurencin et al 1996;Anselme et al 1999), but a direct comparison of the results with the clinical data on the patients is impossible.…”

“…Bone regeneration can be facilitated both by systemic factors and by local insertion of bone‐substitute materials. In maxillofacial surgery, various types of bone defects (atrophied alveolar ridge, periodontal bone destruction, cystic and tumorous jaw lesions and traumatic bone deformities) give rise to a need for local bone replacement (Moy et al 1993; Aygit et al 1999; Groeneveld et al 1999). Maxillary and mandibular bone alterations require excellent cosmetic reconstruction and also a good load‐bearing capacity because of the masticatory forces.…”

Evaluation of the effects of Ankaferd haemostat application on bone regeneration in rats with calvarial defects: histochemical, immunohistochemical and scintigraphic study

“…On the other hand, three-phase bone scintigraphy is a non-invasive technique that shows the vascularity and osteoblastic activity of the bone. In their study using different bone grafts, Aygit et al (1999) evaluated vascularity and osseous changes with bone scintigraphy.…”

“…In this study, they noted that bone scintigraphy could be used as a non-invasive method to evaluate implant vascularity because of histological changes and scintigraphic findings [2].…”

Using fractal dimension to evaluate alveolar bone defects treated with various bone substitute materials

“…For the clinician it would be valuable to assess the bone regeneration after the implantation of different biomaterials. The effect of various grafts including allogenic bone, alloplastic bone substitutes and their combinations [15][16][17][18][19]20,21] have been extensively studied in animal models [22][23][24][25]26] and in vitro experiments [27,28]. There has also been research assessing the augumentation process with the use of clinical, histological and histomorphometrical analysis in humans [29].…”