Effect of surface treatment of a glass-infiltrated alumina ceramic on the microtensile bond strength

This study evaluated the microtensile bond strength of a resin composite to a ceramic submitted to three surface treatments. Twelve glass-infiltrated alumina ceramic blocks (In-Ceram Alumina, VITA) and twelve resin composite blocks (Clearfil APX, Kuraray) with dimensions of 6mm x 6mm x 5mm were made. The surface of the ceramic was wet-grounded with # 600, 800 and 1200-grid sandpaper, and the blocks were divided in three groups: Group 1 - sandblasting with aluminum oxide - particles 110mm (Micro-Etcher, Danville); Group 2 - Rocatec System (ESPE): Tribochemical silica coating (Rocatec pre-powder + Rocatec-Plus powder + Rocatec-Sil); Group 3 - CoJet System (3M/ESPE): silica coating (silica oxide + ESPE-Sil). The ceramic blocks were cemented to the resin composite blocks with Panavia F (Kuraray Co), following the manufacturer's instructions, under load of 750g for 10min. The samples were stored (distilled water / 7 days / 37O C) and sectioned in two axis, x and y, with diamond disk under cooling in order to obtain samples (S) with 0.6 ± 0.1mm2 of adhesive area (n=36). The S were attached in adapted device for the microtensile test that was performed at an universal testing machine (EMIC), at a speed of 1mm/min. The results (MPa) were submitted to ANOVA and Tukey's test (p<0.05): G1 - 15.36; G2 - 30.98; G3 - 31.25. Groups 2 (Rocatec) and 3 (CoJet) presented larger bond strength than group 1. There was no statistical difference between group 2 and group 3.     

Comparison of nutritional counseling between provider types

OBJECTIVE: The goal of this study was to compare the provision of and attitudes toward nutritional counseling between pediatricians and pediatric dentists. METHODS: Questionnaires were mailed to 500 US members of the American Academy of Pediatric Dentistry and the American Academy of Pediatrics. RESULTS: The survey had a response rate of 33% (pediatric dentists=36%; pediatricians=29%). 84% of pediatricians routinely offered nutritional counseling compared to 71% of pediatric dentists. With respect to cariogenic foods, 82% of pediatric dentists and 74% of pediatricians correctly recommended bottle contents, and 33% of pediatric dentists and 19% of pediatricians correctly recommended snacks. 79% of pediatric dentists compared to 69% of pediatricians believed nutritional counseling had at least some effectiveness. Eighty-nine percent of both specialties somewhat or strongly agreed that nutritional counseling was an important aspect of oral health care. CONCLUSIONS: While pediatric dentists made slightly better recommendations than pediatricians regarding cariogenic foods, both provider types demonstrated a need for more education regarding nutritional counseling.     

The effects of systemic alendronate with or without intraalveolar collagen sponges on postextractive bone resorption: a single masked randomized clinical trial

Alendronate is a bisphosphonate frequently used to reduce bone resorption. It has been used for osteoporosis, Paget's disease, and also as adjunctive therapy for periodontal disease. The aim of this study was to evaluate the effect of systemic alendronate with or without endoalveolar collagen sponge on vertical bone resorption after lower wisdom tooth extraction. Forty patients referred for wisdom tooth impaction were selected. Before surgery, patients were randomly assigned to receive one of the following pharmacologic treatments: no medication (group 1), postextractive endoalveolar collagen sponge (group 2), systemic alendronate for 4 months starting the day of surgery (group 3), and group 2 + group 3 (group 4). Standardized orthopantomographic evaluation was obtained during recruitment (T1), immediately after surgery (T2), and 4 months (T3) to evaluate crestal and alveolar socket changes. Results indicate that at T2, crest and socket level did not show significant differences between the four groups. At T3, test sites treated showed less bone resorption compared with controls. In particular, higher vertical bone height levels and a faster intraalveolar healing were achieved in groups 3 and 4. Systemically given alendronate may be used successfully to reduce vertical bone resorption after wisdom tooth extraction.     

POLARIZATION OF DENTAL CARIES AMONG INDIVIDUALS AGED 15 TO 18 YEARS

Objective:

To evaluate the role of socioeconomic variables and self-perceived oral health in the polarization of caries among adolescents in Santa Bárbara D''Oeste, Brazil.

Material and Methods:

Cross-sectional study. Sampling was randomized and sample size was defined according to WHO criteria. Two hundred and seventy seven adolescents (15 to 18 year-old) were examined by five trained examiners that assessed DMFT index according to WHO criteria. Self-perceived oral health, access to dental services and socio-demographic variables were self-reported. Student''s t tests, chi-square tests, and multivariate logistic regression (with significant caries index (SiC) as the outcome), were performed.

Results:

Mean DMFT was 5.48 (±4.22) and the proportion of "caries free" subjects was 15.5%. Mean DMFT (9.71±2.85) and mean D (1.67±2.18) of SiC positive subjects were significantly higher than mean DMFT (2.88±2.17) and mean D (0.45±0.87) of SiC negative subjects (p<0.0001). Mean D of white (0.76±1.51) was significantly smaller than mean D of non-white subjects (1.32±2.01). The only variable independently associated with the "SiC positive" outcome was "report of toothache within six months prior to the study" [OR=1.83 (95%CI 1.08 to 3.12)], p<0.001.

Conclusion:

SiC was associated with "report of toothache" but not with sociodemographic variables in the studied population.     

Effect of different finishing and polishing techniques on the surface roughness of microfilled, hybrid and packable composite resins

This study examined the average surface roughness (Ra, microm) of 2 microfilled (Durafill and Perfection), 1 hybrid (Filtek Z250) and 2 packable composite resins (Surefil and Fill Magic), before (baseline) and after eight different finishing and polishing treatments. The surface roughness was assessed using a profilometer. Ten specimens of each composite resin were randomly subjected to one of the following finishing/polishing techniques: A -- carbide burs; B -- fine/extrafine diamond burs; C -- Sof-Lex aluminum oxide discs; D -- Super-Snap aluminum oxide discs; E -- rubber polishing points + fine/extrafine polishing pastes; F -- diamond burs + rubber polishing points + fine/extrafine polishing pastes; G -- diamond burs + Sof-Lex system; H -- diamond burs + Super-Snap system. Data were analyzed using two-way ANOVA and Tukey's HSD test. Significant differences (p<0.05) were detected among both the resins and the finishing/polishing techniques. For all resins, the use of diamond burs resulted in the greatest surface roughness (Ra: 0.69 to 1.44 microm). The lowest Ra means were obtained for the specimens treated with Sof-Lex discs (Ra: 0.11 to 0.25 microm). The Ra values of Durafill were lower than those of Perfection and Filtek Z250, and these in turn had lower Ra than the packable composite resins. Overall, the smoothest surfaces were obtained with the use the complete sequence of Sof-Lex discs. In areas that could not be reached by the aluminum oxide discs, the carbide burs and the association between rubber points and polishing pastes produced satisfactory surface smoothness for the packable and hybrid composite resins, respectively.     

Rapid prototyping: a new method of preparing trays for indirect bonding.

This article describes a new method of preparing trays for indirect bracket bonding. Computer-aided technology is used to design the individualized trays, which are then produced with a rapid prototyping procedure. Application in clinical practice and the advantages of time savings and accurate bracket placement are discussed.     

High concentrations of soluble P-selectin are associated with risk of venous thromboembolism and the P-selectin Thr715 variant

BACKGROUND: The cell adhesion molecule P-selectin has an important role in the pathophysiology of thrombosis. The effect on venous thromboembolism (VTE) of increased circulating concentrations of soluble P-selectin (sP-selectin) and their association with the P-selectin variant Thr715Pro is still uncertain. METHODS: This study was a case-control study of 116 patients with confirmed recurrent VTE and at least 1 event of unprovoked deep venous thrombosis or pulmonary embolism, and 129 age- and sex-matched healthy individuals. We measured sP-selectin by ELISA and P-selectin gene (SELP) variation by genotyping and sampled blood after a mean interval of 2.55 years after the most recent VTE event. RESULTS: The mean (SD) sP-selectin concentration was higher in patients than in controls: 47.3 (15.0) microg/L vs 36.8 (11.0) microg/L, P <0.001. The unadjusted odds ratio (OR) for sP-selectin >55.1 microg/L, representing the 95th percentile for controls, was 8.5 (95% CI, 3.7-23.3; P <0.001) and increased after adjustment for factor V Leiden, the prothrombin G20210A variant, increased factor VIII, and hyperhomocysteinemia (OR, 10.6; 95% CI, 4.1-31.2; P <0.001). Pro715 carriers were more prevalent among controls than patients (21.7% vs 14.7%). sP-selectin concentrations were lower in this subgroup than in noncarriers: 31.3 (7.9) microg/L vs 44.1 (14.1) microg/L; P <0.001). CONCLUSIONS: Increased sP-selectin concentrations are associated with VTE and genotype status. sP-selectin concentrations are lower in individuals carrying the P-selectin Pro715 variant than in those without this variant.     

Cataract in chronic cluster headache: two case reports and review of the literature

Cluster headache (CH) consists of attacks of severe, unilateral orbital/supraorbital/temporal pain, lasting for 15–180 min, occurring once or more times a day, and associated with ipsilateral conjunctival injection, lacrimation and other symptoms. Cataract is clouding of the lens of the eye causing a progressive and painless loss of vision. We describe the cases of two men (not relative, but with the same last name, which originates from north-eastern Italy) that in young adult age, after years of suffering from chronic CH, developed cataract on the same side of the pain attacks. Patient 1 was diagnosed as having cataract 18 years after the onset of episodic (and subsequently chronic) CH. Patient 2 began suffering from chronic CH at the age of 44 years and after 8 years he developed cataract. This is the first report of cataract in patient suffering of CH and occurring in the eye affected by the pain attack. No financial support received.