Erratum to: Is smoking a predictor of apical periodontitis?

Abstract

Unfortunately, while analysing the data from our patient sample for follow up projects by the statisticians a misclassification of patients with respect to smoking status was recognized. The number of patients within the smoking groups, i.e. current, former, never smokers, changed, leading to alterations within the descriptive (Tables 1 and 2) and the analytical statistics (Tables 3 and 4). The significances of the data remained unchanged as well as the conclusion “Smoking status did not predict apical periodontitis in females and males in this sample group.” which is supported by the re-calculated data. The authors apologize for any inconvenience the reader and the publisher may have had with this manuscript. The passages with the altered numbers appear below: In the “Abstract”: This cohort study included full-mouth periapical radiographs of 161 subjects, including 66 current smokers, 28 former smokers and 67 individuals who had never smoked. Current male cigarette smokers with <10 or ≥10 pack years showed frequencies of apical periodontitis of 7.9 % and 7.5 %, respectively, compared to 4.1 % in individuals who had never smoked. The corresponding data for female smokers were 5.8 % and 7.4 % in smokers with <10 or ≥10 pack years, respectively, versus 5.2 % in individuals who had never smoked. In the “Materials and Methods” section: Full-mouth periapical radiographs from 161 patients with a total of 4012 teeth (3988 after exclusion of third molars) were analysed independently by two examiners (FR, BT). After the calibration procedure, 3988 teeth from 161 patients were scored according to the aforementioned criteria. All analyses were performed with the statistical package R (The R Foundation for Statistical Computing Version 2.15.1). In the “Results” section: Among female current smokers with <10 and ≥10 pack year histories, the mean numbers of teeth per subject were 25.1 and 24.3, respectively, compared to 24.7 in females who had never smoked. Males displayed a trend of higher mean numbers of teeth in each smoking category compared to females, with male current smokers with <10 pack year histories having 26.5 teeth, current smokers with ≥10 pack year histories having 24.5 teeth and those who had never smoked having 24.9 teeth. Overall, 3988 teeth were analysed according to the PAI criteria. After the exclusion of former smokers, 1748 teeth in females and 1551 teeth in males were included and further analysed in the study (Table 2). Current cigarette smoking in females with <10 or ≥10 pack year histories was associated with a higher frequency of apical periodontitis (5.8 % and 7.4 %, respectively) than that found in never smokers (5.2 %). Current cigarette smoking with a <10 pack year history was associated with a pronounced frequency of apical periodontitis (7.9 %) in males. The corresponding frequencies for current smokers with ≥10 pack year histories and never smokers were 7.5 % and 4.1 %, respectively (Table 2). Model 1: The presence of a coronal restoration was a predictor of apical periodontitis in female (OR 3.51, p<0.001) and male (OR 3.11, p<0,001) patients, when the absence of a coronal restoration was used as a reference (Table 3). In this cohort, the presence of a root canal filling was a strong predictor of apical periodontitis in females (OR 9.38, p <0.001) and males (OR 7.14, p<0.001) when compared to the absence of RCF. With respect to a prevalent The online version of the original article can be found at http://dx.doi.org/ 10.1007/s00784-012-0893-z.