Bio-Medical Materials and Engineering - Volume 31, issue 5

Authors: Alam, Khurshid | Iqbal, Muhammad | Umer, Jamal | Amjad, Muhammad | Al-Ghaithi, Ahmed

Article Type: Research Article

Abstract: BACKGROUND: Drilling is a well-known mechanical operation performed for fixing fracture at required locations in bone. The process may produce mechanical and thermal alterations in the structure of the bone and surrounding tissues leading to irreversible damage known as osteonecrosis. OBJECTIVE: The main purpose of this study was to measure the level of biological damage in bone when a drill assisted by low and high levels of vibrations is penetrated into bone tissue. METHODS: Histopathology examination of sections of bones has been performed after drilling the bone using a range of vibrational frequency and rotational speed …imposed on the drill with and without supply of saline for cooling. RESULTS: Cell damage in bone was caused by the combined effect of drill speed and frequency of vibrations. Histopathology examination revealed more damage to bone cells when a frequency higher than 20 kHz was used in the absence of cooling. Cooling the drilling region helped minimize cell damage more at a shallow depth of drilling compared to deep drilling in the cortex of cortical bone. The contribution of cooling in minimizing cell damage was higher with a lower drill speed and frequency compared to a higher drill speed and frequency. CONCLUSION: Vibrational drilling using a lower drill speed and frequency below 25 kHz in the presence of cooling was found to be favorable for safe and efficient drilling in bone. Show more

Keywords: Bone, bone drilling, vibrational drilling, bone temperature, cell damage, bone histology

DOI: 10.3233/BME-201122

Citation: Bio-Medical Materials and Engineering, vol. 31, no. 5, pp. 269-277, 2020

Authors: Ijbara, Manhal | Wada, Kanae | Wada, Junichiro | Jayawardena, Jayanetti Asiri | Miyashin, Michiyo

Article Type: Research Article

Abstract: BACKGROUND: Surface replication is a nondestructive evaluation technique applied in examining surface wear by recording surface irregularities, especially in conditions when surfaces of interest cannot be further manipulated to fit directly under a microscope to be examined. Enamel is the outermost protective layer of the human teeth and is constantly stressed by mastication forces which results in enamel wear. OBJECTIVE: To date, a procedure combining the clinical and microscopic examination of enamel surfaces is absent, which hinders the early diagnosis and comprehension of the wear process. METHODS: This study investigated the role of replication sheets in …registering microscopic wear on human enamel surfaces by both negative and positive replication techniques. RESULTS: The sheets replicated wear features successfully. Sheets were compatible to use with multiple microscopes, with proper preparation, including high resolution microscopes such as the scanning electron microscope and transmitting electron microscope. Show more

Keywords: Surface replication, tooth wear, dental enamel, surface properties, electron microscopy

DOI: 10.3233/BME-206006

Citation: Bio-Medical Materials and Engineering, vol. 31, no. 5, pp. 279-290, 2020

Authors: Ozeki, K. | Ono, A.

Article Type: Research Article

Abstract: BACKGROUND: Removal of radioactive substances, such as cesium (Cs) and strontium (Sr), has become an emerging issue after the Fukushima Daiichi nuclear power plant disaster. It has been reported that hydroxyapatite (HA) and aluminosilicate composite powders can be used to remove Cs and Sr. However, the film type of these materials for the removal of Cs and Sr has not been reported. OBJECTIVE: The aim of this study was to assess the possibility of using HA, aluminosilicate, and aluminosilicate/HA composites for the removal of Cs and Sr radioactive substances. METHODS: Aluminosilicate films and HA films were …fabricated using a sputtering technique with diatomaceous earth and HA targets, respectively. The aluminosilicate film was observed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). A comb-shaped HA/aluminosilicate composite film was prepared to take advantage of the adsorption properties of the HA and the aluminosilicate films. The Cs and Sr adsorption on these films were also evaluated. RESULTS: In the XRD patterns, the film sputtered from a diatomaceous earth target under 5.0 Pa of Ar pressure showed aluminosilicate peaks (Na1.82 (Al2 Si3 O10 ) and Al2 SiO5 ) after 8 h of vapor-phase hydrothermal treatment. The film showed higher adsorption of Cs than Sr in Cs and Sr solutions, while the HA film adsorbed far more Sr than Cs. A HA/aluminosilicate composite film was successfully fabricated, and the SEM images showed that the width of the HA region was 230–260 μm, and that of the aluminosilicate region was 170–200 μm. The HA/aluminosilicate composite film showed 84.8 ± 11.5% Cs adsorption and 28.3 ± 1.4% Sr adsorption in a mixed solution of Cs and Sr. CONCLUSION: This study shows the feasibility of using HA films, aluminosilicate films, and HA/aluminosilicate composite films for the removal of radioactive substances such as Cs and Sr. Show more

Keywords: Hydroxyapatite, aluminosilicate, adsorption, cesium, strontium, sputtering, film, radioactive substances

DOI: 10.3233/BME-201121

Citation: Bio-Medical Materials and Engineering, vol. 31, no. 5, pp. 291-305, 2020

Authors: Otsuka, Yuta | Ito, Akira | Takeuchi, Masaki | Pal, Suvra | Tanaka, Hideji

Article Type: Research Article

Abstract: BACKGROUND: To ensure quality and stability, monitoring systems are recommended to analyze pharmaceutical manufacturing processes. OBJECTIVE: This study was performed to predict powder X-ray diffraction (PXRD) patterns of formulation powders through attenuated total reflectance (ATR)-infrared (IR) spectroscopy in a nondestructive manner along with chemometrics. RESULTS: Caffeine anhydrate, acetaminophen, and lactose monohydrate were grinded at six weight ratios. The six sample groups were evaluated using ATR-IR spectroscopy and PXRD analysis. Partial least squares models were constructed to predict the PXRD intensities of the samples from the ATR-IR spectra. The prediction accuracy on the prepared PLS regression models …was as high as R 2 = 0.993. CONCLUSIONS: Linear relationships were obtained between the prediction data set and reference PXRD intensity at each degree. 2D PLS regression coefficient analysis enabled the analysis of the correlation between PXRD patterns and IR spectra. Show more

Keywords: Powder X-ray diffraction analysis, attenuated total reflectance, process analytical technology, infrared analysis

DOI: 10.3233/BME-206003

Citation: Bio-Medical Materials and Engineering, vol. 31, no. 5, pp. 307-317, 2020

Authors: Basgil, Mehmet Can | Kurtoglu, Cem | Soygun, Koray | Uslan, Yunus | Demi̇r, Teyfik

Article Type: Research Article

Abstract: BACKGROUND: The stability of the implant-abutment interface is an important factor that influences load distribution on the marginal bone. OBJECTIVE: In this study, three dental implants with the same connection were subjected to different dynamic loading cycles. The fracture strengths and the horizontal compatibility of implants were assessed. METHODS: Eighty four implant specimens were embedded in a polyacetal cylinder as simulated bone loss of 3 mm from the implant platform. Three of the implants were used to determine the endurance limit. The other specimens were subdivided into four subgroups (n = 6): three for dynamic …+ static loading, and one for static loading (control group). The tests were performed by applying a compression load. The dynamic loading experiments included three different cycles with endurance upper limit loads at a frequency of 10 Hz. RESULTS: The differences between the fracture strength values of the implant brands were found to be statistically significant. However, there were no meaningful differences between the fracture strength values of implants of the same brand. The specimens of the DTI implant system had the lowest strength (647.9 ± 41.5 N) and the SEM analysis indicated that the Implantium implant system had the shortest horizontal gaps. CONCLUSIONS: There was a negative correlation between the fracture strengths and size of the microgaps. The importance of these in vitro results needs to be validated by clinical trials because the loads in the mouth can be applied from various angles. Show more

Keywords: Dental implant, dynamic loading, horizontal gap, internal conical connection

DOI: 10.3233/BME-206008

Citation: Bio-Medical Materials and Engineering, vol. 31, no. 5, pp. 319-328, 2020