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Statement of problem Whether polymerization lights can be used for heating glass ionomer cements (GICs) or glass carbomer (GCP) to improve their mechanical properties is not well established. Purpose The purpose of this in vitro study was to assess the effect of thermo–light polymerization on the flexural strength (FS) of 2 GICs (Fuji IX GP Fast, Ketac Molar) and a GCP. Material and methods Specimens (n=10) were prepared in stainless steel molds (2×2×25 mm), compressed, exposed to 3 polymerization lights (500, 1000, 1200 mW/cm 2 ) for 2 cycles of 40 seconds on each side, and stored in petroleum jelly (37°C, 24 hours). Results Significant FS differences were detected among groups after different thermo–light polymerization regimens (F=50.926, df=11, P <.001). GCP showed the highest mean FS (∼5 times, P <.001) after thermo–light polymerization with power outputs of 1000 (127.1 ±25.8 MPa) and 1200 mW/cm 2 (117.4 ±18.5 MPa), with no significance difference between them ( P =.98), compared with 500 mW/cm 2 (24.1 ±1.7 MPa). For Ketac Molar, compared with autopolymerization setting (15.5 ±3.1 MPa), a significant increase in mean FS (∼2.5 times) was only observed in specimens treated with 1200 mW/cm 2 polymerization light ( P =.03). For Fuji IX GP Fast, only the light with 1000 mW/cm 2 output significantly increased the FS (98.9 ±23.4 MPa, P <.001) compared with the autopolymerization setting (34.9 ±6.4 MPa). Conclusions Thermo–light polymerization accelerated the development of FS in the tested GICs, potentially protecting against saliva contamination during the first 3 to 4 minutes after mixing GIC. Thermo–light polymerization of the glass carbomer with power outputs of 1000 and 1200 mW/cm 2 also substantially increased FS. The clinical advantages of the findings should be validated by in vivo studies. [ABSTRACT FROM AUTHOR]

Statement of problem The loss of posterior teeth has a negative effect on the masticatory efficiency and activity of mastication muscles. How these muscles are affected by partial removable dental prostheses (PRDPs) with different cusp angles is unknown. Purpose The purpose of this clinical study was to evaluate the influence of different cusp angles, with anatomic (33 degrees), semianatomic (20 degrees), and nonanatomic teeth (0 degree), on the masticatory efficiency and muscular activity of participants receiving mandibular bilateral distal PRDPs. Material and methods Fifteen participants consented to the evaluation of masticatory efficiency and electromyographic (EMG) activity with a PRDP with a unified bilateral design. The cusp angles of the artificial teeth were randomly changed from anatomic (33 degrees), semianatomic (20 degrees), and nonanatomic teeth (0 degree). Masticatory efficiency was evaluated by recording 5 parameters, including number of strokes, and time of mastication while the EMG activities of the masseter and temporalis muscles, measured using surface electromyography. The data were analyzed with 1-way ANOVA and the Tukey multiple post hoc test with statistical software (α=.05). Results With regard to masticatory efficiency, PRDPs with anatomic and semianatomic teeth exhibited higher masticatory efficiency than those with nonanatomic teeth, whereas no significant differences were found between PRDPs with anatomic and semianatomic teeth. With respect to EMG activity, the least EMG activity was observed in PRDPs with anatomic teeth, whereas the highest activity was observed with nonanatomic teeth. No significant differences were found between the effect of PRDPs with anatomic and semianatomic teeth on masseter activity. Conclusions Changing the cusp angle from 33 to 20 degrees in PRDPs did not influence the masticatory efficiency or the EMG activity of the masseters. However, it did lead to increased EMG activities of the temporalis muscle. PRDPs with nonanatomic teeth were associated with a significant decrease in masticatory efficiency accompanied by a significant increase in EMG activity. [ABSTRACT FROM AUTHOR]

Perineuriomas are rare tumors of the peripheral nervous system that occur as either intraneural or extraneural lesions. Intraneural perineuriomas generally affect the major nerve branches in the upper extremity, whereas extraneural perineuriomas have a predilection for the subcutaneous tissues of the lower extremities. In this article, we describe the case of an adult patient who had a perineurioma localized to the foot. Level of Clinical Evidence: 4 [Copyright &y& Elsevier]

Washington''s relationships with the “leveraged allies” preferred by realists—those countries that have little choice but to follow America''s lead—have long been considered more reliable than in its relationships with the “natural allies” favored by idealists: prosperous, democratic nations that share the goals and interests of the United States. President Bush''s foreign policy requires these natural allies, but many U.S. government officials are more wary. Uganda under President Museveni is a model “natural ally” candidate, with its relatively humane and democratic internal policies, but its greater capacity to act without American leverage, approval, or supervision is likely to worry realist career diplomats. [Copyright &y& Elsevier]

Focuses on the influence of religion on political reforms in Latin America in the 20th century. Procapitalist leanings of the Catholic Church since the 1900s; Rejection of democracy and capitalism by liberation theologists; Confusion of Catholic social thoughts among evangelical Protestants; Opportunities for political collaboration between the evangelicals and Catholics.

Explores the impact of Catholic social thought on the Latin America's politics and economy. Analysis of party types in Latin America as useful predictor of the future of economic reform and democratization; Economic elements of Catholic social thought; Chilean success story; Venezuelan Christian Democrats' failure to learn from their Chilean counterparts.

Introduction: The purpose of this study was to evaluate 3-dimensionally the changes on tooth surfaces after debonding orthodontic brackets and after removing residual adhesive and finishing. Methods: Sixty premolars were randomly divided into 2 groups, and brackets were bonded according to the manufacturers’ instructions. Two types of orthodontic adhesives were used: resin-modified glass ionomer cement (group 1) and resin-coated adhesive precoated brackets (group 2). The brackets were debonded on a testing machine at a cross-head speed of 1 mm per minute. Models were made of each tooth before bonding, after debonding, and after removal of residual adhesive. The models were scanned with a 3-dimensional laser scanning machine, and the scanned images were analyzed by using modified analytical software. Results: The Mann-Whitney test showed significant differences in adhesive thickness and enamel loss between the 2 groups (P <.001). The mean (± SD) thickness for group 1 was 31.2 μm (± 26.5 μm), and the mean (± SD) thickness for group 2 was 102.7 μm (± 79.71 μm). The means (± SD) for enamel losses after cleaning and finishing the enamel surfaces were 22.8 μm (± 17.67 μm) for group 1 and 50.5 μm (± 31.27 μm) for group 2. Conclusions: Adhesive thickness and enamel loss due to orthodontic procedures can successfully be measured in vitro by using 3-dimensional laser scanning technology. [Copyright &y& Elsevier]

Objectives: To evaluate the efficacy of tooth bleaching using ozone after hydrogen peroxide (H2O2) in comparison to the use of H2O2 alone.Methods: 70 extracted teeth were randomly distributed into two groups. Teeth surfaces in group 1 (n=35) were treated using 38% H2O2 and then were exposed to ozone for 60s and this ozonated peroxide mixture was left on the teeth for 20 min. Meanwhile, teeth in group 2 (n=35) were treated with H2O2 38% for 20 min. The L* a* b* and Vita Classic shade values of teeth were evaluated in both groups at base line, after application of H2O2 and ozone in group 1, and after application of H2O2 and then again after another application of ozone in group 2. The statistically significant changes were set at P ≤ 0.05.Results: Baseline L* a* b* and Vita shade values were comparable between groups (P>0.05). Teeth obtained lighter shades following bleaching with both H2O2 and ozone or with H2O2 alone (P ≤ 0.05). Further bleaching with ozone for teeth already bleached with H2O2 alone showed further improvement of the shades of teeth (P<0.001). Teeth treated with H2O2 and ozone had more shade improvements than those only treated with H2O2 (P<0.001). Also, L* values were increased while b* values were decreased (teeth obtained lighter shades) following bleaching in both groups (P ≤ 0.05). More changes were obtained when both ozone and H2O2 were used (P ≤ 0.05).Conclusions: Bleaching with 38% H2O2 and ozone resulted in teeth with lighter shades than bleaching with 38% H2O2 alone. [ABSTRACT FROM AUTHOR]

Objectives: To investigate dental impacts on daily living and satisfaction with removable complete and partial prosthodontic rehabilitations, and to identify their relationship with personality profiles. Methods: Sixty-eight patients (38 males and 30 females; mean age = 53.2 ± 11.8 years) received removable prostheses (32 complete dentures and 36 removable partial dentures). Clinical success of prostheses was assessed according specific criteria. The Dental Impact on Daily Living (DIDL) questionnaire was utilized to assess satisfaction with prostheses and impacts on daily living. NEO Five Factor Inventory (NEO-FFI) was utilized to assess patients' personality profiles. Results: Participants' total satisfaction and satisfaction with appearance, pain tolerance, oral comfort, and eating improved after treatment ( p < .05). Position of prosthesis and age had no significant relationships with satisfaction or personality scores ( p > .05). Females were less satisfied with appearance ( p < .05). Patients who received partial dentures were more satisfied with eating and scored higher total satisfaction scores than those who had complete dentures ( p < .05). Before treatment; Neuroticism and Openness scores were associated with dental satisfaction and impacts ( p < .05). After treatment, Conscientious- ness and Extraversion scores were associated with dental satisfaction and impacts ( p < .05). Conclusions: Patients satisfaction with oral condition improved following using removable prosthetic rehabilitation with RPD having better impacts than CD. Psychological profiles (e.g. Neuroticism, Extraversion, Openness and Conscientiousness) might play a role and explain prosthetic impacts on daily living and patients' satisfaction with prostheses. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to quantify tooth wear in upper anterior teeth using a new CADCAM Laser scanning machine, tool maker microscope and conventional tooth wear index. Methods: Fifty participants (25 males and 25 females, mean age = 25 ± 4 years) were assessed for incisal tooth wear of upper anterior teeth using Smith and Knight clinical tooth wear index (TWI) on two occasions, the study baseline and 1 year later. Stone dies for each tooth were prepared and scanned using the CAD-CAM Laser Cercon System. Scanned images were printed and examined under a toolmaker microscope to quantify tooth wear and then the dies were directly assessed under the microscope to measure tooth wear. The Wilcoxon Signed Ranks Test was used to analyze the data. Results: TWI scores for incisal edges were 0-3 and were similar at both occasions. Score 4 was not detected. Wear values measured by directly assessing the dies under the toolmaker microscope (range = 113-150 μm, mean = 130 ± 20 μm) were significantly more than those measured from Cercon Digital Machine images (range = 52-80 μm, mean = 68 ± 23 μm) and both showed significant differences between the two occasions. Conclusions: Wear progression in upper anterior teeth was effectively detected by directly measuring the dies or the images of dies under toolmaker microscope. Measuring the dies of worn dentition directly under tool maker microscope enabled detection of wear progression more accurately than measuring die images obtained with Cercon Digital Machine. Conventional method was the least sensitive for tooth wear quantification and was unable to identify wear progression in most cases. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: This study aimed to evaluate the reliability of a new CAD-CAM Laser scanning machine in detection of incisal tooth wear through a 6-month period and to compare the accuracy of using this new machine against measuring tooth wear using tool maker microscope and conventional tooth wear index. Methods: Twenty participants (11 males and 9 females, mean age=22.7 years, SD=2.0) were assessed for incisal tooth wear of lower anterior teeth using Smith and Knight clinical tooth wear index (TWI) on two occasions, the study baseline and 6 months later. Stone dies for each tooth were prepared and scanned using the CAD-CAM Laser Cercon System (Cercon Smart Ceramics, DeguDent, Germany). Scanned images were printed and examined under a toolmaker microscope (Stedall-Dowding Machine Tool Company, Optique et Mecanique de Precision, Marcel Aubert SA, Switzerland) to quantify tooth wear and then the dies were directly assessed under the microscope to measure tooth wear. The Wilcoxon Signed Ranks Test was used to analyse the data. Results: TWI scores for incisal edges were 0, 1, and 2 and were similar at both occasions. Scores 3 and 4 were not detected. Wear values measured by directly assessing the dies under the tool maker microscope (range=517–656μm, mean=582μm, and SD=50) were significantly more than those measured from the Cercon digital machine images (range=132–193μm, mean =165μm, and SD=27) and both showed significant differences between the two occasions. Conclusions: Measuring images obtained with Cercon digital machine under tool maker microscope allowed detection of wear progression over the 6-month period. However, measuring the dies of worn dentition directly under the tool maker microscope enabled detection of wear progression more accurately. Conventional method was the least sensitive for tooth wear quantification and was unable to identify wear progression in most cases. [Copyright &y& Elsevier]