ABSTRACT
Background To identify the CT features of anterior mediastinal thymoma and lymphoma and evaluate CT findings that may help in suggesting specific diagnosis among these tumors
Method A total of fifty-eight chest CT scan studies with pathological diagnosis of thymoma [n = 30] and lymphoma [n =28] were retrospectively reviewed by two radiologists who were blind to the pathological results. The CT features showing cyst and calcification within the lesion, contrast enhancement, relation with pleura and adjacent vessels, bone invasion and lymph node enlargement were evaluated
Results In lymphoma [67.9%], the presence of associated mediastinal lymphadenopathy was significantly compared to thymoma. [P < 0.05]. The presence of calcification within the lesion was significantly found in thymoma than the lymphoma [p <0.05]. The presence of adjacent vessels relationship within the lesion was higher in lymphoma than the thymoma. [p <0.05] The remaining CT findings showed no significant difference among these diseases [p > 0.05]
Conclusion In conclusion age, lymph nodes involvement, calcification and relationship to adjacent vessels on CT scan will be helpful to give specific diagnosis on anterior mediastinum lymphoma and thymoma
ABSTRACT
Background Lingual orthodontics [LiO] has developed rapidly in recent years and research on treatment of overbite by using Rocking Chair Arch [RCA] wire of different curve depths is still limited, especially with 3-dimensional Finite Element [FE] models. The main objectives are to study the biomechanical differences in maxillary anterior teeth between lingual and labial orthodontics and observe the lingual mechanics on different inclinations of teeth
Methods The force produced by Nickel-Titanium, Stainless Steel [SS] RCA for both sides was measured using Electromechanical Universal Testing Machine. 6 FE models were constructed and divided into 2 groups according to SS wire of 0.016x0.022-inch standard and mushroom arch shaped RCA of curve depth 2, 4, 6 mm. Additional 9 FE models were constructed and divided into 3 groups based on Retroclination [-5[degree sign], -10[degree sign]] and Proclination [+10[degree sign]]
Results Use of same diameter of SS RCA with same curve depth but on different sides shows more stress and strain, displacement of teeth in lingual mechanics. Also, stress-strain, displacement increased with increasing RCA curve depth. In LiO, intrusion of normally inclined or proclined teeth are accompanied by little or no labial tipping whereas that of retroclined teeth is accompanied by further lingual tipping
Conclusion In the intrusion using Lingual RCA, to avoid the traumatic force to teeth, the curve depth should be lesser than Labial RCA or apply more elastic arch material; Aligning different inclined teeth into normal inclination firstly and proceed with the application of intrusive force can be the best approach