Nano/micro fluorhydroxyapatite crystal pastes in the treatment of dentin hypersensitivity: an in vitro study.

OBJECTIVES: Dentin hypersensitivity (DH) is a prevalent problem. This study aimed to formulate a paste using fluorhydroxyapatite (FA) crystals dispersed in different carriers to treat DH. The ability to occlude patent dentinal tubules and to release ions was investigated. MATERIALS AND METHODS: Twenty percent FA/sodium alginate, 40% FA/poly(hydroxyethyl methacylate(HEMA)), and 40% FA/poly(DMA-co-MEA) were applied to etched dentin samples and examined with scanning electron microscopy (SEM) to determine the degree of tubule occlusion. Fluoride electrode was used to measure F release and spectroscopy to evaluate Ca and PO4 release. The cytotoxicity of the synthesized poly(DMA-co-MEA) gel was tested. Kruskall-Wallis test was used to test the differences in ion release between the groups. RESULTS: FA/poly(DMA-co-MEA) paste obstructed up to 80% of the dentinal tubules, while the coverage was up to 70% for FA/poly(HEMA) and less than 50% for FA/sodium alginate. Fluoride and Ca release was the highest for FA/P(HEMA), 7.2 ± 0.7 and 139.8 ± 32.5 ppm, respectively. The highest concentration of PO4 was 46.2 ± 16.4 ppm for FA/Sodium alginate. No statistical significance was found. CONCLUSIONS: FA/Poly(DMA-co-MEA) and FA/poly(HEMA) pastes may offer immediate short-term relief of DH because of their ability to occlude the tubules and adhere to wet dentin surfaces. The release of the F, Ca, and PO4 ions may offer long-term relief by forming a mineral barrier both within the dentinal tubules and on the dentin surface. CLINICAL SIGNIFICANCE: The tested materials may offer a long-term treatment for DH.

Students' opinions and attitudes after performing a dental OSCE for the first time: a Jordanian experience.

This study at the Faculty of Dentistry, University of Jordan investigated and evaluated students' attitudes and opinions after attempting a dental objective structured clinical examination (OSCE) for the first time. The OSCE consisted of sixty-seven stations for fourth-year dental students. After the exam, students were asked to voluntarily complete a questionnaire designed to evaluate their attitudes and opinions about the exam. Of the 134 students who participated in the OSCE, 93.2 percent completed the questionnaire; 43.4 percent said they found the exam difficult and 56.6 percent found it easy (p=0.147). Seventy percent reported that the exam was objective, while 30 percent did not (p<0.001); 65.5 percent indicated that it was a better test than traditional patient-based tests, whereas 34.5 percent did not (p<0.001). Sixty-eight percent stated that there were too many stations, while 30.9 percent stated the number of stations was appropriate and 0.8 percent stated there were too few (p<0.001). Of these respondents, 75.6 percent reported the exam was organized, whereas 21.1 percent said the exam was not very well organized and 3.3 percent said the exam was not organized at all (p<0.001). Overall, the students responded that the OSCE was able to test their clinical judgment and skills and it was a better method for evaluating their clinical skills; most preferred to have such tests in the future. Although the students reported the exam had too many stations, they perceived that it was well organized and that the time allocated for each station was appropriate. These dental students perceived that the OSCE was a suitable method to test operative dentistry clinical judgment and skills.

Hypocone reduction and Carabelli's traits in contemporary Jordanians and the association between Carabelli's trait and the dimensions of the maxillary first permanent molar.

The objective of this study is to determine the prevalence of expression and bilateralism of two dental morphological traits in contemporary Jordanians: The hypocone reduction trait on the maxillary second permanent molar and Carabelli's trait on maxillary permanent first and second molars. Furthermore, inter-trait correlation and the relationship of Carabelli's traits with upper first molar dimensions were investigated. Three hundred subjects of school children at their 10th grade and of an average age of 15.5 +/- 0.4 years were involved. Alginate impressions for the maxillary arch were taken, dental casts were reproduced. The selected accurate casts were of 132 male- and 155 female-students. The frequencies of hypocone reduction trait on the maxillary second molar and Carabelli's trait on the maxillary molars were examined. Buccolingual and mesiodistal diameters of the maxillary first molar were measured and recorded. Paired Sample t test and Nonparametric Correlation analysis were used for data analysis. Hypocone reduction trait on the maxillary second molar was found in 29.8% of the examined students. Positive forms of Carabelli's trait on first and second molars were observed in 65.0% and 3.8%, respectively. Nonparametric correlation analysis revealed positive association between Carabelli's trait on first molar and hypocone reduction trait on the maxillary second molar. The presence of Carabelli's trait on first molar was strongly associated with the increase of buccolingual, but not the mesiodistal, diameter. Bilateralism was found highly significant in the tested traits and both genders (p < 0.001). This finding might be a sign of relatively low environmental stresses in the living Jordanian population and/or great ability of its individuals to buffer the adverse effects of such stresses.

The effects of disinfectants on dimensional accuracy and surface quality of impression materials and gypsum casts.

BACKGROUND: The study aimed to evaluating the effect of disinfecting impression materials on the dimensional accuracy and surface quality of the resulting casts. METHODS: Impressions of a steel die constructed according to ANSI/ADA specification No.18 were made with each of alginate, addition cured silicone, condensation cured silicone and zinc oxide eugenol paste, and disinfected consequently by each of 0.2% chlorhexidine gluconate, 1% sodium hypochlorite, 2% gluteraldehyde for 5 minutes, and 0.5% sodium hypochlorite for 10 minutes. Dimensions of the disinfected impressions and their resultant casts were measured using a computerized digital caliper, and the dimensional changes were calculated. Reproduction of detail and surface quality of the resultant casts were assessed by grading casts surfaces according to a specific scoring system. RESULTS: The 0.5% sodium hypochlorite was found to produce the least dimensional changes in all the impression materials. Corsodyl produced the maximum changes in both alginate and zinc-oxide eugenol while addition-cured silicon was most affected by Gluteraldehyde and condensation-cured silicon was most affected by Hexana. The dimensional changes, however, were minimal and clinically insignificant. Addition-cured silicon showed the best surface quality and dimensional stability followed by condensation-cured silicon. Alginate and zinc-oxide eugenol had poorer surface quality and were affected to a higher extent by the disinfection procedures. CONCLUSIONS: The results were comparable with the standard specifications for dimensional stability. Recommendations were made for the use of 10 minutes immersion in 0.5% sodium hypochlorite as the most appropriate disinfection protocol to the investigated impression materials. KEYWORDS: Disinfectants; Gypsum casts; Impressions; Alginate; Addition-cured silicone; Sodium hypochlorite.

The relationships of the maxillary central incisors and canines to the incisive papilla in Jordanians.

AIM: The validity of the relationship between the maxillary anterior teeth and the incisive papilla and the pertinence of this relationship to Jordanians was examined. METHODS AND MATERIALS: A computerized digital caliper (CDC) tool was developed and used in the measurements which were made on scanned images of dental casts of 298 Jordanians. The distances from a tangent to the labial surface of the central incisors to the midpoint and the posterior border of the incisive papilla were measured. The tool was also used in marking the exact point on the incisive papilla of the intersection with the line that connected the tips of the maxillary canines. The data sets were analyzed statistically and comparisons among various sets were drawn at a 95% confidence level. RESULTS: Gender had no significant effect on the relationship of the incisive papilla to the maxillary anterior teeth, whereas this relationship was significantly influenced by the incisal classifications of the examined subjects. CONCLUSION: Differences between the Jordanian scores and the Caucasian norms were insignificant. CLINICAL SIGNIFICANCE: Therefore, the guidelines recommended for Caucasians could be used as starting points in the preliminary location of maxillary incisors and canine teeth during construction of dentures for Jordanians.

Prevalence, association, and sexual dimorphism of Carabelli's molar and shovel incisor traits amongst Jordanian population.

INTRODUCTION: The correlation between dental morphological traits can be used as an indicator to show major ethnic differences. Therefore, this study investigated the prevalence of Carabelli's molar and shovel incisor traits and tested their association and sexual dimorphism in Jordanian population. MATERIAL AND METHODS: Three hundred subjects of school children at their 10th grade and of 15.5-year as an average age were involved. Alginate impressions for the maxillary arch were taken, poured, and casts were then trimmed. The selected accurate casts were of 132 male- and 155 female-students. The examined morphologic traits were Carabelli's trait on the maxillary first and second molars and shovel-shaped incisors. The relationship between different traits was investigated by Nonparametric Correlation analysis and Independent Sample t test was used to test sexual dimorphism in trait expression. RESULTS: The prevalence of Carabelli's trait in maxillary first molar and shovel trait in maxillary central incisor was relatively high (65.0 % and 53.0 %, respectively). The prevalence of Carabelli's trait on maxillary second molars was 3.8 %. Nonparametric Correlations revealed a strongest positive correlation between Carabelli's trait on maxillary first molar and shovel trait in males (P = 0.005). Significant sexual dimorphism was only found in the prevalence of Carabelli's trait on maxillary first molar (P = 0.013) and shovel trait (P = 0.038). CONCLUSIONS: The Jordanian Population had comparatively high prevalence of Carabelli's molar and shovel incisor traits. There was a positive association between Carabelli's trait on maxillary first molar and shovel trait in males. Sexual dimorphism was evident in Carabelli's trait on maxillary first molar and shovel trait.