A new digital tool for radiographic bone level measurements in longitudinal studies.

BACKGROUND: The reproducibility of measurements on radiographs is influenced by the techniques by which the images as well as the measurements are obtained. Thus, bias resulting from errors in the image and/or image examinations at two points in time may result in wrongful registrations of true biological or pathological changes. The aim of the present study was to propose and evaluate an indirect radiological examination technique, by which bias, when measuring radiographic bone level, could be substantially reduced as compared to the technique using direct mm measurements. METHODS: A plugin to ImageJ was designed to reduce bias when measuring bone loss on radiographic images. In human dry mandibles, radiographic images of 20 teeth were obtained parallel with the tooth axis (alpha = 0) and at an angle of 30° deviation. The direct technique of measuring radiographic bone level (RBL) and the indirect, length-adjusted RBL were registered by four researchers in a double blinded fashion. RESULTS: When mean RBL measured at 0° angle was 7.0 mm, the corresponding mean RBL measured at 30° angle was 7.8 mm, signifying an 11.4% increase (p = 0.032), whereas the mean length-adjusted RBL increased by 0.6% (p = 0.9). CONCLUSIONS: This study showed that the use of the original, direct technique (ImageJ) resulted in markedly biased radiographic bone level at 30° angle, while the proposed indirect length-adjusted technique (ImageJ plugin) did not.

Association between moderate to severe psoriasis and periodontitis in a Scandinavian population.

BACKGROUND: The aim of the present study was to compare the prevalence of periodontitis and alveolar bone loss among individuals with psoriasis and a group of randomly selected controls. METHODS: Fifty individuals with psoriasis and 121 controls completed a structured questionnaire, and were examined clinically and radiographically. Oral examination included numbers of missing teeth, probing pocket depth (PPD), clinical attachment level (CAL), presence of dental plaque and bleeding on probing, as well as alveolar bone loss from radiographs. Questionnaires requested information on age, gender, education, dental care, smoking habits, general diseases and medicament use. For adjustment for baseline differences between psoriasis individuals and controls the propensity score based on gender, age and education was computed using multivariate logistic regression. A subsample analysis for propensity score matched psoriasis individuals (n = 50) and controls (n = 50) was performed. RESULTS: When compared with controls, psoriasis individuals had significantly more missing teeth and more sites with plaque and bleeding on probing. The prevalence of moderate and severe periodontitis was significantly higher among psoriasis individuals (24%) compared to healthy controls (10%). Similarly, 36% of psoriasis cases had one or more sites with radiographic bone loss ≥3 mm, compared to 13% of controls. Logistic regression analysis showed that the association between moderate/severe periodontitis and psoriasis remained statistically significant when adjusted for propensity score, but was attenuated when smoking was entered into the model. The association between psoriasis and one or more sites with bone loss ≥3 mm remained statistically significant when adjusted for propensity score and smoking and regularity of dental visits. In the propensity score (age, gender and education) matched sample (n = 100) psoriasis remained significantly associated with moderate/severe periodontitis and radiographic bone loss. CONCLUSIONS: Within the limits of the present study, periodontitis and radiographic bone loss is more common among patients with moderate/severe psoriasis compared with the general population. This association remained significant after controlling for confounders.

The plaque- and gingivitis-inhibiting capacity of a commercially available essential oil product. A parallel, split-mouth, single blind, randomized, placebo-controlled clinical study.

BACKGROUND: Studies have reported commercially available essential oils with convincing plaque and gingivitis preventing properties. However, no tests have compared these essential oils, i.e. Listerine(®), against their true vehicle controls. OBJECTIVE: To compare the plaque and gingivitis inhibiting effect of a commercially-available essential oil (Listerine(®) Total Care) to a negative (22% hydro-alcohol solution) and a positive (0.2% chlorhexidine (CHX)) control in an experimental gingivitis model. MATERIALS AND METHODS: In three groups of 15 healthy volunteers, experimental gingivitis was induced and monitored over 21 days, simultaneously treated with Listerine(®) Total Care (test), 22% hydro-alcohol solution (negative control) and 0.2% chlorhexidine solution (positive control), respectively. The upper right quadrant of each individual received mouthwash only, whereas the upper left quadrant was subject to both rinses and mechanical oral hygiene. Plaque, gingivitis and side-effects were assessed at day 7, 14 and 21. RESULTS: After 21 days, the chlorhexidine group showed significantly lower average plaque and gingivitis scores than the Listerine(®) and alcohol groups, whereas there was little difference between the two latter. CONCLUSION: Listerine(®) Total Care had no statistically significant effect on plaque formation as compared to its vehicle control.

Prevalence and severity of vestibular recession in mandibular incisors after orthodontic treatment.

OBJECTIVE: To assess the prevalence and severity of vestibular gingival recession of mandibular incisors after orthodontic treatment and to evaluate possible contributing factors. MATERIALS AND METHODS: From the record pool of patients who completed orthodontic treatment from 1999-2006 at the Department of Orthodontics, University of Oslo, Norway, 588 patients fulfilled the inclusion criteria. Intraoral color slides were used for the evaluation of gingival recessions (based on Miller classification), presence of visible plaque, and gingival inflammation. Cephalometric radiographs were used to assess the sagittal intermaxillary relation, mandibular and intermaxillary angles, and the position of the lower incisors. A control group was drawn from the same pool of 588 patients. All statistical analyses were performed using SPSS. RESULTS: The prevalence of gingival recessions after orthodontic treatment was 10.3%. Most (8.6%) were classified as Miller Class I, and 1.7% were classified as Miller Class II. Gingival recession was predominantly found on central incisors. Reduction of the sagittal intermaxillary angle and retroclination of the lower incisors was correlated with the development of a more severe gingival recession. CONCLUSIONS: The present study indicates that vestibular gingival recession of mandibular incisors after orthodontic treatment is of minor prevalence and severity. The presence of gingival recession or retroclination of the incisors with mesial basal relations increases the risk of more severe gingival recession.

Colony morphologies, species, and biotypes of yeasts from thrush and denture stomatitis.

OBJECTIVE: To study the species and phenotypic characteristics of yeasts, i.e. colony morphology, biotypes, and biotype relatedness, and the oral distribution of yeasts, in thrush and denture stomatitis. MATERIAL AND METHODS: Yeast colony morphology was observed under a stereo-microscope and photographed with a digital camera. Genus, species, and biotypes of the yeast isolates were identified by using a commercial kit, ID 32C. Yeast biotype dendrograms were generated by Spotfire software and SPSS 15.0 for Windows. RESULTS: Multiple colony morphologies were observed among the yeasts from both thrush and denture stomatitis. One genus, 6 species, and 21 biotypes were identified among the yeasts from thrush, while 2 genera, 7 species, and 20 biotypes were identified among the yeasts from denture stomatitis. Considerable similarities in predominant species, biotypes, and biotype clustering profiles were shown among the yeasts from thrush and denture stomatitis. However, Candida dubliniensis was identified exclusively in subgingival areas and biotype 7347340215 of C. albicans was identified more frequently in palate and sulci in thrush. CONCLUSIONS: A diversity of species and phenotypes was found among the yeasts in thrush and denture stomatitis. Candidal commensals were predominant in thrush and denture stomatitis, but the observation of divergent Candida species and biotypes, constituting 23% of all the yeast isolates, should not be ignored.

Effects from pretreatment of stannous fluoride versus sodium fluoride on enamel exposed to 0.1 M or 0.01 M hydrochloric acid.

Preventing enamel erosions caused by acidic soft drinks or from vomiting during eating disorders is a challenge in current dental research. The aim of this study was to examine whether pretreatment of dental enamel with a solution of 0.4% SnF2 could prevent dissolution of human enamel exposed to solutions of 0.1 M HCl, pH 1.2 or 0.01 M HCl at pH 2.2. Human enamel was pretreated for 18 h with a solution of 0.4% SnF2 and with control solutions of 2% NaF or distilled water, and then exposed to HCl solutions. Similar experiments were performed with teeth treated for 2 min SnF2 and then 4 min HCl. The effect was monitored by scanning electron microscopy (SEM) and by chemical analysis. At pH 2.2, NaF and water treatments showed minor inhibition of enamel dissolution, whereas SnF2 inhibited demineralization significantly also after 2 min pretreatment and 4 min HCl exposure. At pH 1.2, SEM showed severe dissolution of the enamel surfaces regardless of pretreatment. As pH of stomach vomit is usually > 1.5, SnF2 may be an interesting agent for use in the treatment and prevention of dental erosions even in patients with frequent vomiting episodes.