non-PRP Group Research Articles

Efficacy of PRP in the Reconstruction of Mandibular Segmental Defects Using Iliac Bone Grafts

This retrospective study was conducted to evaluate the role of platelet-rich plasma (PRP) in the reconstruction of segmental mandibular defects using iliac bone grafts. Thirteen patients underwent reconstruction of post-resection segmental defects of the mandible using titanium reconstruction plates, cortico cancellous iliac bone graft. The patients were randomly separated into two groups. One group of the patients received a PRP graft in addition to the iliac bone graft. Post-operative dimensions of the graft were measured and compared to assess the efficacy of PRP in reconstruction of segmental defects. The post-operative follow-up radiographs confirmed consolidation of the graft in all cases and the segmental defect was obliterated. Thereby mandibular continuity was successfully achieved in all cases. Two patients in the non-PRP group developed an infection and were administered additional antibiotics. The infection was contained and the grafts survived. The use of PRP along with autogenous bone graft may be advantageous since it appeared to enhance the quantity of bone formed. Further long-term follow-up and studies are required to effectively establish the efficacy of PRP and autogenous free bone grafts in the reconstruction of bony defects.

Choroidal changes of macular edema with serous macular detachment in non-proliferative diabetic retinopathy patients

[Objective] To observe the choroidal changes of diabetic macular edema (DME) with serous macular detachment (SMD) in non-proliferative diabetic retinopathy (NPDR) patients by optical coherence tomography (OCT),[Methods] Nine NPDR patients including DME with SMD in one eye (SMD group) and only DME in the other eye (DME group) were enrolled.These 18 eyes were also divided into PRP group (six eyes,received panretinal photocoagulation before) and non-PRP group (12 eyes).Spectral domain EDI (enhance depth imaging)-OCT and fundus photograph were performed in all the eyes.The subfoveal choroidal thickness was measured.The choroidal simulation area acquired by horizontal EDI-OCT scan through the center of the foves was calculated by Image Plus Pro 6.0 software.The difference between DME and SMD group was compared and analyzed with matched t test; the difference between PRP and non-PRP group was compared and analyzed with F test.[Results] In SMD group,spindle-like or dome-like low signal of detachment areas with intact external limiting membrane were found in the retinal detachment region,and the inner and outer segments (IS/OS) were separated from the retinal pigment epithelium (RPE)-Bruch membrane.Both subfoveal choroidal thickness and choroidal simulation area in SMD group were significant greater than those in DME group (t=2.306,2.306 ;P＜0.05).Choroidal simulation area in PRP group was larger than that in non-PRP group (F =5.227,P＜0.05).But there was no significant difference of subfoveal choroidal thickness between PRP and non-PRP group (F =3.276,P＞ 0.05).[Conclusion] EDI-OCT detects spindle-like or dome-like low signal areas in detachment region of SMD with DME in NPDR patients. Key words: Diabetic retinopathy/complications; Macular edema/etiology; Tomography, optical coherence; Diagnostic imaging

Platelet rich plasma improves the healing process after airway anastomosis,

This study investigated whether platelet-rich plasma (PRP) promotes healing and reduces anastomotic complications following airway surgery in a pig model. PRP was obtained by spinning down the animal's own blood (60 ml) and collecting the buffy coat containing platelets and white blood cells. Fifteen adult pigs were randomized into three groups: (1) sham treatment (cervicotomy), (2) non-PRP group (50% tracheal resection and end-to-end anastomosis), and (3) PRP group (50% tracheal resection, end-to-end anastomosis and PRP application). Blood samples were taken at baseline and at one, six and 24. Animals were monitored for anastomotic complications, infection and local reactivity. Laser Doppler flowmetry was performed intraoperatively and at 30 days to assess differences in pre- and post-anastomotic blood flow. The tensile strength of the anastomosis was also tested. The platelet level was higher in PRP fluid than in the baseline blood sample (P<0.002). Vascular endothelial growth factor, transforming growth factor β-1 and epidermal growth factor immunoassay readings peaked at one and six hours in the animals that had received PRP (P<0.03); these also showed significantly increased transanastomotic flow and stress-strain resistance (P<0.04) at 30 days than the animals that had not received PRP. PRP therefore, accelerates the onset of healing in airway surgery by promoting an earlier release of platelet-derived growth factors that stimulate transanastomotic angiogenesis.

A quantitative radiological assessment of outcomes of autogenous bone graft combined with platelet-rich plasma in the alveolar cleft

This longitudinal study evaluated the outcomes of secondary autogenous bone graft combined with platelet-rich plasma (PRP) in the alveolar cleft. Thirty-five alveolar clefts in 30 patients with grafted autogenous bone and PRP (PRP group), and 36 clefts in 30 patients with grafted autogenous bone alone (non-PRP group) were enrolled. PRP was extracted from autogenous blood using a plasma centrifuge system (SmartPReP SMP-1000). The density and resorption of grafted bone were evaluated at 1 week, and 1, 3, 6 and 12 months postoperatively. Bone density was quantitatively assessed as an aluminum-equivalence (Al-Eq) value. Moreover, relationships between bone resorption rate and prognostic factors were discussed. Al-Eq values decreased significantly until 3 months, and then increased up to 12 months in both groups. The Al-Eq rate in the PRP group was significantly smaller than that in the non-PRP group at 3 months. No significant differences were observed in the bone resorption rate between the groups. Regarding prognostic factors, continuous mechanical stress affected bone resorption with or without PRP. The authors suggest that PRP may enhance bone remodeling in the early phase, however, PRP seems to be insufficient as a countermeasure against bone resorption following secondary bone graft in the long term.

Effect of platelet-rich plasma on bone regeneration in autogenous bone graft

In this study, we evaluated the effect of platelet-rich plasma (PRP) on bone regeneration in an autogenous bone graft in a canine model. The mandibular premolar teeth had been bilaterally extracted previously, and the ridges had been allowed to heal for 3 months. After this period, continuity resection was performed on both sides of the mandible. One defect (the PRP group) was reconstructed with the original particulate bone mixed with PRP. As a control, the contralateral defect (non-PRP group) was reconstructed with the original particulate bone alone. Biopsies after 6 weeks showed lower levels of bone formation in the PRP group than in the non-PRP group, and fluorescence microscopy revealed a delay in the remodelling of grafts loaded with PRP. These findings suggest that the addition of PRP does not appear to enhance new bone formation in autogenous bone grafts.