[Validity of teeth width measurements on conventional versus 3D models]

For proper diagnosis of orthodontic problems of a patient, different measurements and analysis should be performed on dental cast. In recent years, due to introduction of paperless offices, 3D reconstruction methods and softwares are available in order to build virtual dental casts and measurements on them. The purpose of the present study was to compare the validity of teeth width measurements on conventional versus 3D models. In this diagnosis study, twenty set-ups of upper and lower casts using artificial teeth corresponding to various malocclusions were created. Impressions were taken of them providing 20 plaster models. The plaster models were scanned by laser surface scanner and the crown widths measured by its software. The gold standard was the teeth width measured by caliper before setting up the teeth. The mesiodistal crown width was also measured on casts as conventional method. The crown width was compared between the three methods by F test, ICC and Dahlberg formula. Coefficient of validity between measurements by 3D scanning and gold standard in overall teeth measurements [premolar to premolar] was 0.914. The mean difference between laser scanning method and gold standard was 1.7 mm and between conventional method and gold was 0.34 mm. In most of the measurements, the difference between mesiodistal crown width belonged to canines. The accuracy of laser surface scanning system was clinically acceptable and in the range of similar studies, but these is not enough for research purposes and it should be improved. In reference to advantages of computerized methods in near future, these methods will be the clinical standard for orthodontic diagnosis

Study of 20 cases of Castleman's disease in Iran

Twenty histologically documented cases of Castleman's disease [CD] are reported, consisting of 13 males and 7 females with age range from early infancy to 49 with an average of 24 years. The disease was localized in ten cases [50%] and multicentric in the rest [50%]. Histologically, fifteen cases [75%] were hyaline vascular [HV], three cases [15%] plasma cell [PC], and two cases [10%] of intermediate type. Patients were followed from 5 to 185 months. Seven patients [35%] are alive with no evidence of disease. Thirteen patients [65%] had recurrent, or intermittent disease despite local excision, or surgery plus chemotherapy; in seven of these [35%] the disease was complicated by concurrent, or subsequent malignancies including: Kaposi's sarcoma [2 cases] Hodgkin's disease [2 cases], malignant lymphoma [2 cases] and one case of angiomatoid malignant fibrous histiocytoma [MFH]. The last case was the only one with fatal outcome [5%] at the time of this writing. Compared to the other series, our cases of Castleman's disease occurred in a younger age group, mostly in men and with cervical lymphadenophaty. A combination of oral chemotherapy consisting of prednisolone and chlorambucil was beneficial after surgery as tried on the cases that showed multiple recurrences