Effect of nanocrystalline hydroxyapatite socket preservation on orthodontically induced inflammatory root resorption

Orthodontically induced inflammatory root resorption [OIIRR] is considered to be an important sequel associated with orthodontic tooth movement [OTM]. OTM after Socket preservation enhances the periodontal condition before orthodontic space closure. The purpose of this study is to investigate the histologic effects of NanoBone[R], a new highly nonsintered porous nano-crystalline hydroxyapatite bone on root resorption following OTM. This experimental study was conducted on four male dogs. In each dog, four defects were created at the mesial aspects of the maxillary and mandibular first premolars. The defects were filled with NanoBone[R]. We used the NiTi closed coil for mesial movement of the first premolar tooth. When the experimental teeth moved approximately halfway into the defects, after two months, the animals were sacrificed and we harvested the area of interest. The first premolar root and adjacent tissues were histologically evaluated. The three-way ANOVA statistical test was used for comparison. The mean root resorption in the synthetic bone substitute group was 22.87 +/- 11.25×10[-4] mm[2] in the maxilla and 21.41 +/- 11.25×10[-4] mm[2] in the mandible. Statistically, there was no significant difference compared to the control group [p>0.05]. The use of a substitution graft in the nano particle has some positive effects in accessing healthy periodontal tissue following orthodontic procedures without significant influence on root resorption [RR]. Histological evaluation in the present study showed osteoblastic activity and remodeling environment of nanoparticles in NanoBone[R]

Evaluation of tissue interaction and orthodontic tooth movement following application of FDBA and DFDBA

The purpose of this study was to investigate the histologic interaction between two different allografts and first premolar root; following orthodontic tooth movement. Sample consisted of four male dogs. In each animal, four defects were created at the mesial aspects of the maxillary and mandibular first permanent premolars. The defects were filled with DFDBA or FDBA equally. NiTi closed coil with 150 gr force was used for mesial movement of the first premolar. When the experimental teeth were had been moved about halfway into the defect spaces i.e.nine weeks, the animals were sacrificed and the area of interest were harvested. The first premolar root and adjacent tissues were histologically evaluated. Tooth movements were analyzed using paired t test. The findings demonstrated that it was possible to move a tooth into a defect, filled with DFDBA or FDBA with the same rate of tooth movement. Mean tooth movement in DFDBA and FDBA was 2.6 +/- 0.11 mm in DFDBA and 2.4 +/- 0.12 mm in FDBA. Apical root resorption occurred on the pressure sides in both groups. These findings indicate that FDBA and DFDBA could be a biocompatible bone substitute into bone defects subjected to orthodontic tooth movement