AbstractAim: The present study aimed to investigate the effectiveness of PRF in the treatment of infrabony defects in patients with chronic periodontitis by evaluating the clinical outcome through periodontal depth, clinical attachment level at the baseline, 6 and 9 months post operatively.Material and Methods: Sixty infrabony defects with probing depth ≥ 5 mm were treated. The inclusion criterion was the necessity for surgical bilateral maxillary treatment. By using split-mouth study design, each patient had one side treated with conventional flap surgery and the other side with conventional flap surgery and PRF. Clinical parameters, such as probing depth (PD) and clinical attachment lost (CAL), were recorded in both groups at baseline, 6 and 9 months post operatively.Results: Positive effects for all clinical and radiographic parameters were evident in the group with PRF. Mean PD reduction demonstrated statistically significant greater results in the test group (4.00±1.07 mm) compared to the control one (4.83±0.99 mm), p = 0.003 after 9 months postoperatively. After 9 months, there were better results in the test group compared to the control group for CAL (5.60±1.61 mm, 6.20±1.58 mm), but statistically not significant.Conclusion: Additional use of PRF in the conventional surgical treatment of infrabony defects demonstrated better parameters than the open flap debridement alone.

Traffic congestion is defined as mutual obstruction of traffic by vehicles due to the existing relation between the speed of vehicles and the flow in conditions of exceeding the capacity of the infrastructure. The paper presents an analysis of local experts survey on the role of non-motorized and motorized ways of travel to reduce congestion, as well as a comparison with the assessments given by foreign experts. The performance and the impact of different modes of transport (motorized and non-motorized) on congestion in urban conditions were assessed. The impact of the mode of transport on congestion was assessed using measures that are usually implemented in cities. Possibilities for improving multimodal mobility with an emphasis on walking and cycling have also been identified, as the most perspective ways due to the relatively low costs of implementation and the potential to affect the modal distribution.