Radiographic Vertical Bone Loss Evaluation around Dental Implants Following One Year of Functional Loading

Objective: Vertical bone loss evaluations in the Nobel Biocare Replace® Select Tapered TM implant system in the human after one-year loading time.Materials and Methods: This retrospective cross-sectional study was performed on 31 patients (14 men, 17 women; mean age, 60.39 years) receiving 170 implants (mean, 5.48 for each patient) of Groovy and Non-groovy designs in the Nobel Biocare Replace® Select Tapered TM system. The marginal bone loss was measured at mesial and distal aspects of the implants on OPG x-rays after one-year follow-up. The data regarding the patient's gender, age, history of disease, smoking, bone type at implant location, loading time of prosthesis and implant, implant design, diameter and length were recorded by the patients'records and interview. The data were subjected to multiple linear regression and Pearson coefficient ratio regarding different factors.Results: The mean (standard deviation) distal, mesial and overall bone loss was 0.688 mm (0.851), 0.665 mm (0.849) and 0.935 mm (0.905), respectively in the studied implants. No significant differences were found regarding implant location, bone quality at the implant region, implant design and bone graft reception. In addition, no significant correlation was found between the occurred bone loss and implant diameter, length and number of usedsplints.Conclusion: Due to the criteria mentioned for implant success in term of bone loss values after one-year loading time, Noble Biocare Replace® Select Tapered TM implant system is an acceptable treatment option for implant restorations in this regard

An in-vitro study on the accuracy of conventional film optical densitometry and densitometry in radiovisiography system

Nowadays, bone mass estimation, through imaging methods, is widely used in metabolic"ndiseases diagnosis and treatment. One of these methods is called "optical densitometry" which estimates bone density by measuring the intensity of the transmitted light on different parts of a radiographic image. Digital radiography systems act similarly by determining grey levels of the image. The aim of this study is comparing two different methods of optical densitometry and a digital system densitometry known as radiovisiography. 45 samples, containing urografin with three different concentrations, were imaged, by both radiovisiogrphy (RVG) and conventional film systems. To determine the densitometry of films and radiovisiography images, optical densitometry and bone densitometry option of the RVG software, were applied respectively. Data were analyzed and compared for their reliability (repeatability) and correlations with concentration. In RVG densitometry system, the correlation with concentration is moderate (r=0.42) and intra samples and intra group reliability are 97.68% and 88.19%. Moreover, in conventional optical film densitometry, correlation with concentration (r=0.987) is high, intra samples and intra group reliability is high, intra samples and intra group reliability are 99.97% and 99.84%, respectively. According to the results, it is suggested that conventional film optical densitometry is more precise and reliable than RVG densitometry

Mechanical and thermal properties of Carpinas betulus fiber filled polypropylene composites

WOS: 000506395200001The aim of this study is to demonstrate whether Carpinus betulus L. (CB) powder can be used as an alternative filler/reinforcement material for polypropylene (PP). About 5, 10, 15, and 20 wt% CB loaded PP composites were prepared by a high-speed thermokinetic mixer. in this article, the effects of weight fraction of CB within PP on thermal, viscoelastic, chemical, mechanical, crystallographic, and morphological properties of PP composites were investigated by tensile and three-point bending test, dynamic mechanic analysis, thermogravimetric analysis, differential scanning calorimetry, Fourier transform infrared analysis, and scanning electron microscopy. Melting temperature of the composites decreased with the increase of CB content. the crystallization temperature of PP increased with the addition of CB into PP. When 10 wt% CB filler was loaded into PP, the tensile of PP increased by about 29 wt%. the storage modulus of PP were remarkably enhanced with increasing CB weight fraction. About 5 wt% CB addition into PP increased the flexural strength of PP by about 32%