Helicobacter pylori and gastric hyperacidity, and their association with recurrent aphthous stomatitis.

Helicobacter pylori is an established cause of gastric ulcers. Its role in causing recurrent aphthous stomatitis (RAS) remains controversial. Fifty-two RAS patients and 52 sex-matched controls were recruited in this case-control study. All subjects were screened for hematinic deficiencies and H. pylori. The latter was assessed quantitatively using the 14C-urea breath test. The χ2 test and Wilcoxon signed ranks test were used to compare H. pylori and hematinic indices between cases and controls, while conditional logistic regression was used to assess the associations between the occurrence of RAS and independent factors. H. pylori was positive in 56.7% of the overall sample, with no difference between RAS patients (50.8%) and controls (49.2%) (P = 0.843). The median H. pylori and haematological indices values did not show any association with ulcer diameter, number, or frequency. Interestingly, gastric hyperacidity was significantly associated with RAS, and this association was independent from tobacco smoking, alcohol drinking, and H. pylori (odds ratio 14.99, 95% confidence interval 2.47-90.95; P = 0.003). This study found no association between H. pylori and RAS. The association between RAS and gastric hyperacidity suggests that gastric refluxate, not H. pylori, has an effect on the oral mucosa that favours an ulcerative change.

Evaluation of two dental identification computer systems: DAVID and WinID3.

Human identification, by comparing dental characteristics, is considered to be one of the most reliable, accurate and rapid methods of resolving the identity of visually un-identifiable deceased persons. In recent decades computer programs have evolved to aid odontologists by suggesting records that have similar dental features. The aim of the present study was to compare two of those programs; Disaster And Victim IDentification (DAVID) and WinID3 in terms of effectiveness, accuracy and speed of data entry and to further compare them with the efficiency of the classical method of manually matching postmortem and antemortem dental records. An open disaster was simulated whereby 52 fragmented remains made of acrylic replicas and 77 provisional victims were represented on Interpol F2 postmortem and antemortem forms. The results assessed were the first seven possible matches made by each program. Manual matching of dental characteristics performed better than both programs (P<0.001) yielding 29 identifications. Eleven and six positive matches were the result of the DAVID and the WinID3 programs respectively (P=0.185). Data entry was quicker for WinID3. It was concluded that both programs are still not as accurate as the time-consuming manual matching method. The difference in performance between the DAVID and the WinID3 programs was attributed to the inclusion of more comparable dental characteristics, the inclusion of the type of dentition (deciduous or permanent) and the weighting of those characteristics by the DAVID program.