An In Vitro Study to Evaluate the Retention of Complete Crowns Prepared with Five Different Tapers and Luted with Two Different Cements

This study includes comparatively evaluating and drawing general conclusion about the best advisable taper and cement for maximal retention. Eighty extracted human maxillary premolar teeth with sound surfaces were selected using dial vernier caliper. Selected teeth were randomly divided into five different taper groups (0°, 3°, 6°, 9° and 12°). The crown preparations with different tapers respectively were achieved by graduated customized device. Preparations were verified with special set up. Crowns were cast with Co–Cr alloy; metal copings were luted with glass ionomer and zinc phosphate cement. Retention was measured (MPa) by separating the metal crowns from the teeth under tension on a universal testing machine, data was recorded and statistically analyzed. Glass ionomer cemented 0° and 12° taper group showed increase in retentive strength (p = 0.003 hs), when compared to zinc phosphate cement. 9° and 12° group showed decreased retentive strength (p = 0.001 vhs) when compared with 0° taper group. No significant difference found between 0° and 3° and 6° group. The choice of cement for crowns prepared within this ideal range (0°–6° taper) might be of limited clinical significance. 3° and 6° taper with zinc phosphate or glass ionomer cement shown to be ideal for maximum retention.     

Oral verrucous carcinoma. An analysis of 37 cases

37 cases of oral verrucous carcinoma, occurring over a period of six years from 1981-1986, were analysed in respect of the clinical, radiological and histological findings. A delineation of the clinical presentation of this tumour, and the relation of habits to the occurrence of the lesion, has been clarified. The connotation of the term verrucous hyperplasia and its differences from verrucous carcinoma, have been discussed. Surgery and radiotherapy both seem to give good results as methods of treatment, especially when coupled with adequate nutrition and cessation of harmful habits.     

Elongated styloid process (Eagle's syndrome): a clinical study.

PURPOSE: Elongated styloid process can be a source of craniofacial and cervical pain and remains a diagnostic challenge to many. The aim of the study was to determine the symptomatology and various criteria for the diagnosis of an elongated styloid process and its management. PATIENTS AND METHODS: Our clinical study consisted of 58 patients with elongated styloid process who had symptoms of vague cervicofacial pain and presented to our department during a period of 10 years. Special emphasis is given to palpation of the tonsillar fossa, lidocaine infiltration test, and orthopantomography. RESULTS: Minimal complications and zero incidence of deep neck infection were noted. CONCLUSIONS: All of the patients were managed surgically through the intraoral approach, which was found to be a safe procedure.     

Severe hepatotoxicity associated with use of a dietary supplement containing usnic acid

Dietary supplements containing usnic acid are marketed for weight loss and have been associated with hepatotoxicity. The specific ingredient responsible for the hepatotoxicity is currently unknown. We describe 2 patients who developed severe hepatotoxicity within 3 months of taking a dietary supplement containing usnic acid. One patient developed fulminant hepatic failure requiring emergency liver transplantation; the other developed submassive hepatic necrosis but did not require transplantation. Thorough investigation, including histopathological examination of the liver, revealed no other cause of acute liver injury. Usnic acid hepatotoxicity should be considered as a possible etiologic factor in patients presenting with fulminant hepatic failure, especially if they have been taking dietary supplements for weight reduction.