BACKGROUND AND OBJECTIVES: This paper aimed at evaluating the characteristics of high-frequency (1,000 Hz) acoustic admittance (ya) for the neonates with transient evoked otoacoustic emissions (TEOAE) as either pass or refer group. SUBJECTS AND METHODS: Using a 1,000 Hz probe tone, 297neonates (152 male, 145 female aged 0–104 days old) were evaluated. Tympanometric parameters admittance value at +200 dapa, middle ear admittance, and tympanometric peak pressure were calculated for each tympanogram. RESULTS: The mean of ya was 0.9678 mmho in the TEOAE for the pass group and 0.7229 mmho in the refer group. The mean of acoustic admittance at +200 (y200) was 2.0657 in the TEOAE for the pass group and 1.7191 for the refer group. The mean of Tpp was 23/8591 in the TEOAE for the pass group and 59/7619 for the refer group. CONCLUSIONS: There were significant differences in the distribution of different types of tympanograms, the mean of ya, tympanic peak pressure, and y200 between the TEOAEs for the pass and the refer groups.
Acoustic Impedance Tests* ; Acoustics ; Ear, Middle ; Female ; Humans ; Infant, Newborn* ; Male

Purpose: The detection and exact localization of penetrating foreign bodies are crucial for the appropriate management of patients with dentoalveolar trauma. This study compared the efficacy of cone-beam computed tomography (CBCT) and spiral computed tomography (CT) scans for the detection of different foreign bodies composed of 5 frequently encountered materials in 2 sizes. The effect of the location of the foreign bodies on their visibility was also analyzed. Materials and Methods: In this in vitro study, metal, tooth, stone, glass, and plastic particles measuring 1×1×1mm and 2×2×2 mm were prepared. They were implanted in a sheep’s head in the tongue muscle, nasal cavity, and at the interface of the mandibular cortex and soft tissue. CBCT and spiral CT scans were taken and the visibility of foreign bodies was scored by 4 skilled maxillofacial radiologists who were blinded to the location and number of foreign bodies. Results: CT and CBCT were equally accurate in visualizing metal, stone, and tooth particles of both sizes. However, CBCT was better for detecting glass particles in the periosteum. Although both imaging modalities visualized plastic particles poorly, CT was slightly better for detecting plastic particles, especially the smaller ones. Conclusion Considering the lower patient radiation dose and cost, CBCT can be used with almost equal accuracy as CT for detecting foreign bodies of different compositions and sizes in multiple maxillofacial regions. However, CT performed better for detecting plastic particles.

According to literature, certain microorganism productions mediate biological effects. However, their beneficial characteristics remain unclear. Nowadays, scientists concentrate on obtaining natural materials from live creatures as new sources to produce innovative smart biomaterials for increasing tissue reconstruction in tissue engineering and regenerative medicine. The present review aims to introduce microorganism-derived biological macromolecules, such as pullulan, alginate, dextran, curdlan, and hyaluronic acid, and their available sources for tissue engineering. Growing evidence indicates that these materials can be used as biological material in scaffolds to enhance regeneration in damaged tissues and contribute to cosmetic and dermatological applications. These natural-based materials are attractive in pharmaceutical, regenerative medicine, and biomedical applications. This study provides a detailed overview of natural-based biomaterials, their chemical and physical properties, and new directions for future research and therapeutic applications.
Biocompatible Materials/chemistry* ; Humans ; Hyaluronic Acid ; Regenerative Medicine ; Tissue Engineering ; Tissue Scaffolds/chemistry*