Periapical lesions are not always a sequelae of pulpal necrosis: a retrospective study of 1521 biopsies.

AIM: To record the incidence of lesions that were not the sequelae of pulpal necrosis (non-SPN) amongst 1521 biopsies of periapical lesions submitted with a clinical diagnosis of a sequelae of pulpal necrosis (SPN). METHODOLOGY: A retrospective study of 1521 biopsy request forms of specimens submitted for histopathological examination with a clinical diagnosis 'periapical inflammation', 'periapical abscess', 'periapical granuloma' or 'periapical cyst' during an arbitrarily selected 14-year period was undertaken. Gender and age of the patient, site and maximum diameter of the lesion, symptoms, inclusion of the final diagnosis in the differential diagnosis and specialty of the clinician submitting the biopsy material were recorded in each case. The final diagnosis for each case was extracted from the pathology report, and two groups were formed, SPN and non-SPN lesions. Differences between the respective features of SPN and non-SPN cases were analysed with Yate's chi-square test and t-test (significance level P < 0.05) RESULTS: In 52 of the 1521 cases examined (3.42%), the histological diagnosis was not consistent with a SPN. In most non-SPN cases, the histopathological diagnosis was not included in the differential diagnosis. The keratocystic odontogenic tumour [odontogenic keratocyst (OKC)] was the most frequent non-SPN lesion (34.62%). Other, yet less frequent, non-SPN lesions included glandular odontogenic cysts, lateral periodontal cysts, central ossifying fibromas as well as malignancies (metastatic carcinomas and Langerhans cell histiocytosis). CONCLUSIONS: Non-SPN lesions appeared in the periapical region mimicking a SPN, although rarely. Most of them were developmental cysts, in particular OKCs, but odontogenic tumours, such as ameloblastoma, or malignant lesions were also diagnosed. Histological examination of tissue harvested from periapical lesions should be performed, in particular when those lesions are large.

Exploring the effects of lifestyle, sleep factors and driving behaviors on sleep-related road risk: a study of Greek drivers.

PURPOSE: The present study explored the effect of various lifestyle patterns and sleep-related factors on the sleep-related road risk. Sleep-related factors included daytime sleepiness, drowsy driving and quality/quantify of sleep. METHODS: A sample of 1366 non-professional drivers aged 19-65 was selected from the broader Athens area of Greece, using stratified random sampling. The questionnaire solicited information on the participants' socio-demographic characteristics, driving background, lifestyle patterns, sleep quality and quantity, daytime sleepiness, drowsy driving behavior and sleep-related road risk. RESULTS: Sleep-related road risk was affected by gender, quantity of night sleep and drowsy driving behavior. Drowsy driving behavior was shown to be related to gender, daytime sleepiness, sleep quality and the lifestyle of "amusement". Daytime sleepiness was correlated with sleep quality and the lifestyles of "amusement" and "sport". Finally, sleep quality and quantity were significantly affected by the lifestyles of "amusement" and "yuppies-workaholic". CONCLUSION: The current study has identified a number of risk factors in sleep-related crash risk in the general population of drivers. By raising public awareness the health and safety community can play an important role in reducing, if not preventing, the consequences of this public health problem.

A user-centred design approach for introducing computer-based process information systems.

There has been an increasing tendency to use computer-based process information systems as the main interface through which operators interact with complex industrial systems. Although the new technology has produced greater hardware reliability and maintainability, the corresponding potential benefits for operability have not always been achieved. Automation has introduced new forms of design and operating errors. One of the major reasons for this problem has been the lack of human factors advice and user participation early in the design process. This paper discusses a user-centred design approach to increase operability and user acceptance of new technologies and working practices. Application of this approach in the context of a chemical plant indicates its promise, but also highlights the difficulties involved in gaining user participation and management commitment.