Standards of teeth preparations for anterior resin bonded all-ceramic crowns in private dental practice in Jordan

OBJECTIVES: To investigate if general dental practitioners (GDPs) in private practice in Jordan follow universal guidelines for preparation of anterior teeth for resin bonded all-ceramic crowns (RBCs). MATERIAL AND METHODS: A sample (n=100) of laboratory models containing 208 tooth preparations for IPS Empress and In Ceram, featuring work from different GDPs, was obtained from 8 commercial dental laboratories. Aspects of preparations were quantified and compared with accepted criteria defined following a review of the literature and recommendations of the manufactures' guidelines. RESULTS: Subgingival margins on the buccal aspect were noticed in 36% of the preparations, 54% demonstrated overpreparation with a tendency to overprepare the teeth on the mesiodistal plane more than buccolingual plane. Twenty percent of samples presented a shoulder finish line while a chamfer margin design was noticed in 39%. Twenty-nine percent and 12% of samples had either a feathered or no clear margin design respectively. Incisal underpreparation was observed in 18% of dies of each type. Only 17% of all preparations were found to follow the recommended anatomical labial preparations while 29% of the RBC preparations were found to have the recommended axial convergence angle. In total, 43% of preparations were found to have the recommended depth of the finish line. CONCLUSIONS: It was found that relevant guidelines for RBC preparations were not being fully adhered to in private practice in Jordan

Detoxification of crude oil

NoPetroleum contributes significantly to our lives and will continue do so for many years to come. Petroleum derivatives supply more than 50% of the world's total supply of energy (Jarullah, 2011). Traditionally crude oil goes though fractional distillation to produce different grades of fuel such as gasoline, kerosene, diesel oil, etc. providing fuel for automobiles, tractors, trucks, aircraft, and ships. Catalytic hydrotreating (HDT) is used to detoxify the oil fractions produced by fractional distillation in the petroleum refining industries which involve removal of pollutants such as sulfur, nitrogen, metals, and asphaltene in trickle bed reactors. Recently Jarullah and co-workers proposed detoxification of whole crude oil a priori before the crude oil enters further processing in a fractionating column. This chapter highlights this new technology

Tinea Capitis by Microsporum audouinii: Case Reports and Review of Published Global Literature 2000–2016

Tinea capitis caused by Microsporum audouinii is reported herein from two Brazilian schoolchildren, which are brothers. Arthroconidia were evidenced on direct examination of scalp hair, and a fungus of the genus Microsporum was isolated from cultures of each patient. The isolated fungi were classified as M. audouinii by visualization of species-specific structures, including: pectinate hyphae, chlamydospores, and fusiform macroconidia, sterile growth with characteristic brown pigment in rice grains, and through DNA sequencing of the internal transcriber spacer region. Patients were refractory to ketoconazole, but the two cases had a satisfactory response to oral terbinafine. All M. audouinii infections described in this century were reviewed, and to our knowledge, this is the first literature description of this species from South America. Misidentification of M. audouinii with Microsporum canis can occur in this area, leading to erroneous data about the occurrence of this species