ABSTRACT
BACKGROUND: Fused teeth usually involve several complications, such as the development of caries in the groove between fused crowns, tooth impaction, diastemas, aesthetic and periodontal problems, and pulpal pathosis, due to the complex anatomical structure of fused teeth. A thorough diagnosis is paramount to forming an accurate treatment plan and obtaining a favourable prognosis. With the advent of cone-beam computed tomography (CBCT), accurate 3-dimensional images of teeth and their surrounding dentoalveolar structures can now be readily obtained, and the technology can accurately provide a minimally invasive approach to acquire detailed diagnostic information. Therefore, we utilize CBCT data herein to generate a digital model for the infected region in a patient, and this model enables us to better plan the management of his case. CASE SUMMARY: This report details the diagnosis and endodontic treatment of a rare case involving a fused maxillary second molar and two paramolars with apical periodontitis. The patient experienced pain upon biting and cold sensitivity in the area of the maxillary left molar. No caries or other defects were identified in these teeth, and a normal response to a pulp electric viability test was observed. With the aid of CBCT and digital model technology, we initially suspected that the infection originated from the isthmus between the maxillary second molar and two paramolars. Therefore, we only treated the isthmus by an endodontic approach and did not destroy the original tooth structure; furthermore, the vital pulp was retained, and good treatment outcomes were observed at the 24-month follow-up. CONCLUSION: This finding may provide new insights and perspectives on the diagnosis and treatment of fused teeth.
ABSTRACT
Beclomethasone dipropionate (BDP), which is a member in the inhaled glucocorticosteroid class, is commonly used in the treatment of asthma by pulmonary delivery. The purpose of this study is to prepare ultrafine BDP particles for dry powder inhalation (DPI) administration by combining microfluidic antisolvent precipitation without surfactant, high-pressure homogenization (HPH) and spray drying. T-junction microchannel was adopted for the preparation of needle-like BDP particles. The needle-like particles could be easily broken down into smaller particles during HPH, which were assembled into uniform low-density spherical BDP aggregates by spray drying. The effects of the operation parameters, such as the flow rates of BDP methanol solution and antisolvent, the overall flow rate, the BDP concentration, and the change of the injection phase on BDP particle size were explored. The results indicated that the BDP particle size greatly decreased with the reduction of BDP solution flow rate and the increase of antisolvent flow rate. However, the BDP particle size firstly decreased and then increased with the increase of the overall flow rate and the increase of BDP concentration. Also, BDP solution as the injection phase could form the smaller BDP particles. 10 HPH cycles are enough to forming short rod-like particles. After spray drying, the BDP spherical aggregates with a 2-3 µm size could be achieved. They have an excellent aerosol performance, 2.8 and 1.4 times as many as raw BDP and vacuum-dried BDP particles, respectively.
Subject(s)
Anti-Asthmatic Agents/chemistry , Beclomethasone/chemistry , Chemistry, Pharmaceutical/methods , Dry Powder Inhalers , Administration, Inhalation , Anti-Asthmatic Agents/administration & dosage , Beclomethasone/administration & dosage , Drug Compounding , Microscopy, Electron, Scanning , Particle Size , Spectroscopy, Fourier Transform Infrared , X-Ray DiffractionABSTRACT
This article presents the preparation of nanoparticles of amorphous cefuroxime axetil (CFA) in a microporous tube-in-tube microchannel reactor (MTMCR). The experimental results indicated that CFA particle with a tunable size of 400-1400 nm could be achieved under a high throughput in the range of 1.5-6L/min. The average particle size decreased with increasing overall volumetric flow rate and decreasing CFA concentration, micropore size, and annular channel width. The produced CFA nanoparticles were characterized by SEM, XRD, FT-IR, DSC and a dissolution test, which indicated that the nanosized CFA was amorphous and exhibited higher dissolution rate compared to the raw CFA. The MTMCR might offer a general and facile pathway for mass production of the nanoparticles of hydrophobic pharmaceuticals thanks to its high throughput capacity and excellent micromixing performance.
