Evaluation of the Effects of Dual Antiplatelet Therapy on Guided Bone Regeneration in Peri-Implant Bone Defect.

In this study, the authors aim to investigate the effect of dual antiplatelet agents on peri-implant-guided bone regeneraation by studying a sample of rats with titanium implants in their tibias. The rats were randomly divided into 5 groups: acetylsalicylic acid (ASA) (n=10), treated with 20 mg/kg of ASA; ASA+CLPD (Clopidogrel): (n=10), treated with 20 mg/kg of ASA and 30 mg/kg of clopidogrel; ASA+PRSG (Prasugrel): (n=10), treated with 20 mg/kg of ASA and 15 mg/kg of prasugrel; ASA+TCGR (Ticagrelor): (n=10), treated with 20 mg/kg of ASA and 300 mg/kg of ticagrelor; and a control group (n=10) received no further treatment after implant surgery. Bone defects created half of the implant length circumferencial after implant insertion and defects filled with bone grafts. After 8 weeks experimental period, the rats sacrified and implants with surrounding bone tissues were collected to histologic analysis; bone filling ratios of defects (%) and blood samples collected to biochemical analysis (urea, creatinine, aspartate aminotransferase, alanine aminotransferase, phosphorus, magnesium, alkaline phosphatase, calcium, and parathormone). A statistically significant difference was not detected between the groups for all parameters ( P >0.05). When the percentage of new bone formation was examined, it was found that there was no statistically significant difference between the groups ( P >0.05). Antiplatelet therapy may not adversely affect guided bone regeneration in peri-implant bone defects.

Osseointegration Levels of Implants Placed With Allogenic and Xenogenic Bone Ring: An Experimental Biomechanical Analysis.

This in vivo study aimed to do a biomechanical analysis of the early period bone-implant connection of titanium implants simultaneously inserted with xsenogenic and allogenic bone ring. In this study, 28 Sprague Dawley female rats were used. Four rats were killed to obtain an allogenic bone ring, and after this, the remaining rats were divided into control (n=8), xsenogenic (n=8), and allogenic (n=8) bone ring groups. Titanium-machined surfaced implants were integrated right tibias of the rats. In controls, only implants were integrated into right tibias. In the greft groups, the implants were integrated simultaneously with bone rings. After 2 weeks of the experimental period, the rats were killed ,and titanium implants and surrounding bone tissues were removed for biomechanic analysis. After biomechanical reverse torque analysis bone-implant connection was determined as Newton/cm 2 ; in controls 3.26 (1.2 to 4.5), in allogenic ring group 3.37 (2 to 4.4), in xsenogenic ring group 5.93 (2.8 to 10). Statistically significant differences were not detected between the groups ( P >0.05). Within the limitation of this study, both allogenic and xsenogenic bone grafts could be successfully used in bone augmentation in implant surgery.

Evaluation of the Effects of Topical Ellagic Acid and Graft Application on Bone Regeneration: an Experimental Study.

Objectives: The aim of this experimental animal study is to investigate the effect of bone graft and topical ellagic acid application on bone regeneration in rats with critical-sized calvarial bone defects. Material and Methods: A total of 24 male Wistar rats were divided into three groups, and 7 mm critical-sized calvarial bone defects were created surgically in them. In the first group, the created defect was left empty, and this acted as a control group. In the second group, only a bone graft was placed in the created defect. In the third group, in addition to placing a bone graft in the created defect, 0.325 mg/kg ellagic acid (EA) was applied topically to the defect. Results: As a result of semiquantitative scoring, osteoblast counts were 2 (SD 0.82) in the control group, 2.71 (SD 0.76) in the graft group, and 1.14 (SD 0.69) in the EA + graft group. The number of osteocytes was 2.29 (SD 0.76) in the control group, 2.71 (SD 1.11) in the graft group, and 1.43 (SD 0.54) in the EA + graft group. When inflammations were evaluated, values of 1.71 (SD 0.75), 1.14 (SD 0.69), and 3 (SD 0.82) were obtained in the control, graft, and EA + graft groups, respectively. Conclusions: Topical ellagic and graft applications show different effects at different doses under topical and systemic conditions. The dose amount of ellagic acid applied, especially in topical applications, has critical importance in bone healing.