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Carbonate apatite (CO3Ap) granules are known to show good osteoconductivity and replaced to new bone. On the other hand, it is well known that a porous structure allows bone tissue to penetrate its pores, and the optimal pore size for bone ingrowth is dependent on the composition and structure of the scaffold material. Therefore, the aim of this study was to fabricate various porous CO3Ap granules through a two‐step dissolution–precipitation reaction using CaSO4 as a precursor and 30‐, 50‐, 120‐, and 205‐μm diameter microfibers as porogen and to find the optimal pore size of CO3Ap. Porous CO3Ap granules were successfully fabricated with pore size 8.2–18.7% smaller than the size of the original fiber porogen. Two weeks after the reconstruction of rabbit calvarial bone defects using porous CO3Ap granules, the largest amount of mature bone was seen to be formed inside the pores of CO3Ap (120) [porous CO3Ap granules made using 120‐μm microfiber] followed by CO3Ap (50) and CO3Ap (30). At 4 and 8 weeks, no statistically significant difference was observed based on the pore size, even though largest amount of mature bone was formed in case of CO3Ap (120). It is concluded, therefore, that the optimal pore size of the CO3Ap is that of CO3Ap (120), which is 85 μm. [ABSTRACT FROM AUTHOR]

Beta‐tricalcium phosphate granular cement (β‐TCP GC), consisting of β‐TCP granules and an acidic calcium phosphate (Ca‐P) solution, shows promise in the reconstruction of bone defects as it sets to form interconnected porous structures, that is, β‐TCP granules are bridged with dicalcium phosphate dihydrate (DCPD) crystals. In this study, the effects of acidic Ca‐P solution concentration (0–600 mmol/L) on the setting reaction and tissue response to β‐TCP GC were investigated. The β‐TCP GC set upon mixing with its liquid phase, based on the formation of DCPD crystals, which bridged β‐TCP granules to one another. Diametral tensile strength of the set β‐TCP GC was relatively the same, at ∼0.6 MPa, when the Ca‐P concentration was 20–600 mmol/L. Due to the setting ability, reconstruction of the rat's calvarial bone defect using β‐TCP GC with 20, 200, and 600 mmol/L Ca‐P solution was much easier compared to that with β‐TCP granules without setting ability. Four weeks after the reconstruction, the amount of new bone was the same, ∼17% in both β‐TCP GC and β‐TCP granules groups. Cellular response to β‐TCP granules and β‐TCP GC using the 20 mmol/L acidic Ca‐P solution was almost the same. However, β‐TCP GC using the 200 and 600 mmol/L acidic Ca‐P solution showed a more severe inflammatory reaction. It is concluded, therefore, that β‐TCP GC, using the 20 mmol/L acidic Ca‐P solution, is recommended as this concentration allows surgical techniques to be performed easily and provides good mechanical strength, and the similar cellular response to β‐TCP granules. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:22–29, 2020. [ABSTRACT FROM AUTHOR]

Objective: To evaluate whether amniotic fluid glucose concentration can predict poor neonatal outcome in cases with polyhydramnios as an overall assessment. Methods: In this retrospective study, we have reviewed 42 consecutive pregnant women with singleton gestations complicated with polyhydramnios who gave birth at one tertiary care center between January 2003 and September 2010. Perinatal clinical findings were reviewed, and the neonatal outcome, such as livebirth or stillbirth and early neonatal death, was compared. A p value less than 0.05 was considered to be significant. Results: Thirteen of 42 neonates had a poor outcome, including stillbirth or early neonatal death. Multiple logistic regression analysis showed that amniotic fluid glucose ( p = 0.042) was significant factor influencing poor neonatal prognosis [odds ratio 0.66; 95% confidence interval 0.44-0.98]. Receiver operating characteristics curve and sensitivity and specificity curve showed that the optimal cut-off value of amniotic fluid glucose concentration for predicting poor neonatal outcome was 17 mg/dl. Conclusions: Amniotic glucose concentration less than 17 mg/dl and the presence of congenital heart anomaly were better predictors for a poor postnatal outcome in cases with polyhydramnios. [ABSTRACT FROM AUTHOR]

Carbonate apatite (CO3Ap) is an inorganic component of bone. This study aimed to compare the composition and tissue response to of CO3Ap (CO3Ap-DP) fabricated by the dissolution-precipitation reaction using calcite as a precursor and Bio-Oss®, which is widely used in orthopedic and dental fields as a synthetic bone substitute. X-ray diffraction and Fourier transform infrared results showed that CO3Ap-DP and Bio-Oss® were both B-type carbonate apatite with low crystallinity. The average sizes of CO3Ap-DP and Bio-Oss® granules were 450 ± 58 and 667 ± 168μ m, respectively, and their carbonate contents were 12.1 ± 0.6 and 5.6 ± 0.1 wt%, respectively. CO3Ap-DP had a larger amount of CO3 than Bio-Oss® but higher crystallinity than Bio-Oss®. When a bone defect made at the femur of rabbits was reconstructed with CO3Ap-DP and Bio-Oss®, CO3Ap-DP granules were partially replaced with bone, whereas Bio-Oss® remained at 8 weeks after implantation. CO3Ap-DP granules elicited a significantly larger amount of new bone formation at the cortical bone portion than Bio-Oss® at 4 weeks after the implantation. The results obtained in the present study demonstrated that CO3Ap-DP and Bio-Oss® showed different behavior even though they were both classified as CO3Ap. The CO3 content in CO3Ap played a more important role than the crystallinity of CO3Ap for replacement to bone and high osteoconductivity. [ABSTRACT FROM AUTHOR]

Objectives:: Nasopharyngeal tonsilloliths (NT) and eustachian tube tonsilloliths (ET) are not as well-known to radiologists as palatine and lingual tonsilloliths. The aim of this investigation was to determine the prevalence and imaging characteristics of NT and ET using CT and panoramic radiographs., Methods:: We retrospectively assessed the scans of 2244 patients who underwent consecutive CT and panoramic radiographs of the maxillofacial region. The prevalence, size, number, and position of NT and ET were analysed., Results:: NT and ET were detected in 14 (0.6%) and 6 (0.3%) of 2244 patients on CT, respectively, but they were undetectable on panoramic radiographs. No significant difference was found in the prevalence with respect to sex. Although there was also no significant difference in the prevalence among age groups, tonsilloliths were most commonly noted in patients over 40 years old; they appeared as small and round calcified bodies, ranging from 1 to  3 mm in diameter. All NT were found 0 to 3 mm beneath the nasopharyngeal mucosal surface., Conclusions:: The prevalence of NT and ET on CT was lower than that of palatine and lingual tonsilloliths. However, since they are encountered more frequently than clinically significant calcifying diseases such as retropharyngeal calcific tendinitis, clinicians should be able to correctly diagnose NT and ET based on their anatomical features.