New-Onset Monosomy 7-Induced Pancytopenia in a 66-Year-Old Woman.

Myelodysplastic syndrome (MDS) is characterized by failure to initiate hematopoiesis or impaired maturation of cells, often presenting with pancytopenias with or without associated fatigue, infections, or inappropriate bleeding and bruising. Karyotype analyses of MDS patients commonly show deletion of the q arm of chromosome 7, suggesting loss of this region is likely implicated in the insufficient hematopoiesis seen in MDS. The predisposition to deletion of 7q is commonly inherited, with clinical presentation in early childhood associated with pancytopenia or hematological malignancy. In this case, we present a 66-year-old female who was incidentally found to be pancytopenic in the emergency department while being evaluated for dyspnea, with a bone marrow biopsy later confirming a diagnosis of MDS with monosomy 7. Sporadic loss of 7q can occur at any stage in life without any family history of hematological disease. Our patient has no known personal or family history of MDS, with normal blood counts during hospitalization three years prior, suggesting de novo loss of 7q occurring at greater than 60 years of age.

Effects of the preparation technique and type of material on the penetrability of sealants.

The purpose of this in vitro study was to compare the penetration of 2 resin-based and 2 glass ionomer sealants into fissures after either conventional or mechanical preparation. All the materials placed in the conventionally prepared and mechanically prepared fissures penetrated the fissures beyond the standard (0.5-mm) reference line used in this study. For 1 glass ionomer sealant, the number of specimens showing complete penetration of sealant was significantly greater (P < 0.05) in mechanically prepared fissures than in conventionally prepared ones. No significant differences were found between mechanically and conventionally prepared fissures for the other sealants.

An in-vitro evaluation of mechanical and esthetic properties of orthodontic sealants.

OBJECTIVE: To evaluate mechanical and esthetic Properties of two commercially available orthodontic sealants: Opal(®)Seal (OS) and L.E.D. Pro Seal (PS). MATERIALS AND METHODS: Discs of each sealant were prepared to test the following properties: Micro hardness, wear resistance and color stability. Samples were randomly selected after the wear test for SEM imaging to analyze surface morphology. RESULTS: OS was significantly harder than PS (P < 0.001). PS was significantly more wear resistant than OS (P < 0.05). PS showed a greater ∆E*ab (increased staining) when placed in wine or coffee showing a significant difference (P < 0.05). SEM showed particle size, shape and distribution were different for PS and OS reflecting the pattern seen on wear surfaces. CONCLUSION: Both orthodontic sealants are beneficial for protecting enamel. However with better wear properties PS was superior in resisting mechanical stresses. OS was more color stable.

An in vitro comparison of the effects of various air polishing powders on enamel and selected esthetic restorative materials.

OBJECTIVE: The purpose of this study was to investigate the effects of each of the commercially available air polishing powders on the surface characterization of human enamel, hybrid composite, and glass ionomer using a highly standardized protocol. The air polishing powders utilized in the study included aluminum trihydroxide, calcium carbonate, calcium sodium phosphosilicate, glycine, and sodium bicarbonate. METHODS: The hybrid composite and glass ionomer cement were mixed and photo light-cured for 40 seconds according to manufacturer's directions, and formed in a specially prepared mold that was coated using a Teflon aerosolized spray. The enamel samples were prepared by removing sections of human enamel from extracted unerupted third molars using a water-cooled, slow-speed diamond rotary saw. The enamel sections were approximately one centimeter in diameter and 3 mm thick. The enamel sections were flattened using a series of silicon carbide grit papers (600, 800, and 1200 grit) mounted on a rotating polishing wheel. A flat polished enamel surface, at least 5 mm in size, was produced and embedded in the hybrid composite material used for testing purposes, resulting in a sample approximately 10 mm in diameter and 2 mm thick. The restorative material samples were wet-polished to produce a uniform smooth surface and to remove the resin-rich surface layer, using the same series of silicon carbide grit papers used on the enamel (600, 800, and 1200 grit). The 1200 grit abrasive paper used is equivalent to a dental polishing disc commonly used to finish dental restorations. All samples were stored in distilled water at 37 degrees C prior to testing. Each of the three types of samples was treated with each air polishing powder for one, two, and five seconds. A test group of five samples each of hybrid composite, glass ionomer cement, and enamel was fabricated for each of the six types of abrasive powder and three-time exposures for the air polishing treatment, resulting in a total of 270 samples. The treatment samples were exposed to the air polishing powders for the three periods of time using a custom mounting jig and shutter device that was fabricated to standardize the air polishing treatments. The air polishing handpiece was placed in a mounting jig that positioned the tip of the handpiece at an 80 angle from the sample surface. The exposure to the air polishing air, water, and polishing powder was regulated by an articulated metal plate positioned between the tip and the test sample. The holder for the test sample kept the sample in a constant circular motion to simulate clinical use of the air polishing handpiece. A custom computer program was developed to activate a stepper motor that rotated the metal plate away from the sample for the controlled exposure times of one, two, and five seconds before the plate moved back to intercept the polishing spray mixture. RESULTS: The effect of the air polishing application on the surfaces of the tooth enamel and restorative materials was evaluated for changes in surface roughness and surface topography. The average surface roughness value was evaluated with a contact profilometer prior to and after the air polishing treatment. Changes in the surface characterization of each sample due to air polishing treatment were recorded using scanning electron microscopy. Epoxy resin replicas of representative test samples were made for evaluating under the scanning electron microscope. Samples were sputter-coated with gold palladium and the scanning electron photomicrographs were taken at a magnification of 25X and at a 45 degrees angle. Based on evaluation with the contact profilometer, there were statistically significant interactions between the type of powder and material, type of power and time, and type of material and time. The SEM photomicrographs were used to evaluate the clinical significance of the effects of the air polishing on each type of material. The SEM photomicrographs provided a visual quantitative analysis of the effects of air polishing powders on the restorative materials and the enamel. Any disruption of the surface characterization was considered to be clinically significant and represented volumetric loss and violation of the integrity of the restorative materials and/or enamel. CONCLUSIONS: Based on the results of this study, the air polishing powders that are compatible with use on hybrid composite and glass ionomer cements are EMS glycine and EMS sodium bicarbonate. The air polishing powders that are compatible for use on enamel include EMS glycine, Dentsply sodium bicarbonate, and EMS sodium bicarbonate.

Mechanical properties and color stability of provisional restoration resins.

PURPOSE: To evaluate the mechanical strength and color stability of provisional restoration materials. METHODS: For mechanical testing, four groups [Trim (PEMA), Alike (PMMA), Versatemp (bis-acrylic resin composite, BARC) and Perfectemp II (bis-acrylic fluoride enriched resin, BAFC)] of resin disks were prepared for fracture toughness and shear punch strength testing, respectively. Five samples were fabricated for each group; therefore, a total of 20 resin disks for each testing method was prepared. The load at fracture and shear punch values of each specimen were recorded after 24-hour storage in distilled water. The stress intensity factors (K(Ic)) were calculated by the formula reported by Atkinson et al. For shear strength, the following formula was used: Shear strength = Force (N)/section thickness (mm) x punch circumference (mm). Values of each group in both tests were analyzed using one-way-ANOVA and Tukey multiple comparison test. For color stability testing, provisional resin disk specimens of the above mentioned materials were fabricated. Five samples were prepared for each subgroup (with and without a surface coating agent - Permaseal) and three different solutions (distilled water, red wine and curry); a total of 120 disk specimens were fabricated. Color values of each group were measured using a spectrophotometer after 24 hours and 2 weeks of aging in the aforementioned solutions. The color differences (deltaE*ab) between before and after aging were calculated by CIE Lab color-difference formula. The interaction of deltaE*ab values were analyzed by two-way analysis of variance followed by Newman-Keuls Multiple comparison test. RESULTS: The highest fracture toughness value [(MPa (m)1/2)] was obtained by PMMA (0.89) followed by BARC (0.67), PEMA (0.54) and BAFC (0.42). Significant differences were observed among all test groups (P < 0.05). The highest shear punch strength (MPa) was obtained by BARC (160), followed by PMMA (141) and PEMA (132). The lowest value was obtained by BAFC (106). BARC showed a significantly higher mean value than the other groups (P < 0.05). PEMA and PMMA demonstrated better color stability than the two bis-acrylic resin composites. Wine and curry showed higher stainability than water, recording higher deltaE*ab values than the clinically perceptible difference level of deltaE*ab 3.3. The surface coating agent groups demonstrated more staining than the non-coated groups. All groups, except for BARC, demonstrated significant differences dependent upon surface coating and solutions (P < 0.05).

Effects of a paste-free prophylaxis polishing cup and various prophylaxis polishing pastes on tooth enamel and restorative materials.

The application of cleaning and polishing agents to a patient's dentition is a routine part of many dental practices. This study measured the surface roughness and surface gloss of tooth enamel, composite resin, and dental porcelain restorative materials when exposed to a paste-free prophylaxis polishing cup as well as a conventional prophylaxis polishing paste. Samples of human tooth enamel, a composite resin restorative material, and dental porcelain were prepared by a series of polishing papers to produce a flat smooth surface. The baseline average surface roughness (Ra) was measured using a contact stylus profilometer, and the surface gloss was measured with a glossmeter. The test samples were subjected to a standardized polishing routine using a paste-free prophylaxis polishing cup and a fine- or coarse-particle prophylaxis paste. Post-treatment surface roughness and gloss measurements were compared using a paired t statistical test. The conventional prophylaxis pastes increased surface roughness and decreased the gloss of the composite resin and tooth enamel test groups. The paste-free cups did not significantly affect the surface roughness of the enamel or the restorative materials. Dental porcelain surface roughness essentially was not affected by the application of paste-free cups and the fine and coarse pastes.

Laboratory evaluations of a bi-level, extremely tapered bristled toothbrush and a conventional uniform bristled toothbrush.

PURPOSE: To compare a uniquely shaped tapered-bristle manual toothbrush to a toothbrush with bristles uniform in height and diameter for the ability to remove artificial plaque deposits in areas of the mouth that are difficult to access; interproximal areas, the gingival margin and subgingival. METHODS: This study compared a GUM Summit+ Compact toothbrush featuring extremely tapered bristles and conventional bristle ends in a bi-level design. The upper, longest tapered bristles have the final 6 mm tapered to 0.01 diameter mm at the end. The conventional rounded end bristles have less than 0.5 mm tapered down to 0.02 mm diameter. The comparison manual toothbrush (Oral-B 40 Indicator) has bristles that are uniform in height and diameter. Interproximal access efficacy was evaluated using a pressure-sensitive artificial plaque substrate placed around simulated anterior and posterior teeth. Subgingival access and gingival margin cleaning were determined by using simulated gingiva prepared with a 0.2 mm space between the gingiva and the artificial plaque substrate on tooth surfaces and results were recorded as the artificial plaque removed below the gingiva or around the gingival margin. RESULTS: Interproximal access values were significantly (P < 0.001) higher for the GUM Summit+ Compact than for the Oral-B 40 Indicator. The mean value for gingival margin cleaning efficacy of the GUM Summit+ Compact was significantly (P < 0.001) superior compared to the Oral-B 40 Indicator. The Gum Summit + Compact had a significantly superior subgingival access (P < 0.001) mean value when compared to the Oral-B 40 Indicator. In this laboratory study, the GUM Summit+ Compact toothbrush was statistically significantly more effective for removing plaque from the interproximal areas, at the gingival margin and subgingivally than the Oral-B 40 Indicator toothbrush.

Esthetic restorative material shade changes due to photopolymerization.

This study sought to measure color values (before and after photopolymerization) and variations of A1 shade polymeric dental restorative materials. The L*a*b* values of polymeric dental restorative material disks were measured by a spectrophotometer with the specular component excluded (SCE) geometry under D65 illumination over a standardized white background before and after photopolymerization. Color differences (DeltaE*ab) due to polymerization were calculated using the CIE Lab color-difference formula. DeltaE*ab indicates differences between two colors in the L*a*b* color space. In this system, L*, a*, and b* indicate lightness, red-green, and yellow-blue, respectively. Color differences (DeltaE*ab) were calculated by the equation DeltaE*ab = [(DeltaL*)2 + (Deltaa*)2 + (Deltab*)2]1/2. Eight resin composites, three flowable resin composites (FRCs), and two resin-modified glass ionomers (RMGIs) were utilized; L*a*b* and DeltaE*ab values of the test groups were analyzed using ANOVA and Newman-Keuls multiple comparison tests. DeltaE*ab values before and after photopolymerization ranged from 3.01-17.76. All RMGI and two FRC materials displayed greater color changes than the resin composites (p < 0.05). Photopolymerization produced measurable increases and decreases in lightness. Yellow-blue (b*) values decreased in all test groups after polymerization, while most red-green (a*) values increased. Color differences between polymerized A1 shade materials ranged from 0.76-25.41 DeltaE*ab. The color difference between the test materials and a widely used tooth shade guide (the Vita Lumin) was averaged at 12.66 DeltaE*ab.

The effects of a commercial aluminum airpolishing powder on dental restorative materials.

INTRODUCTION: JET-Fresh (Dentsply International, York, PA), a new airpolishing powder that contains aluminum trihydroxide as the abrasive agent, has been introduced for use with Prophy-Jet trade mark (Dentsply International). PURPOSE: The aim of this study was to investigate the surface effects of aluminum trihydroxide airpolishing powder on a series of restorative materials. MATERIALS AND METHODS: A total of 6 Class V preparations with enamel margins were created on the buccal surface of extracted human molars. The preparations were restored with Type III gold, a high copper spherical alloy amalgam, porcelain, a light-activated hybrid composite material, a light-activated microfilled composite material, and a light-activated, resin-modified glass ionomer material. The distal half of each restoration was covered with fiberglass tape and the mesial half subjected to treatment with the aluminum trihydroxide powder via the Prophy-Jet for 5 seconds. After removal of the protective tape, the buccal surface of each treated tooth was replicated with impression material. Replicas were generated using epoxy resin and prepared for evaluation with scanning electron microscopy. RESULTS: The aluminum trihydroxide produced surface alterations that were apparent visually and when viewed by a scanning microscope of the hybrid and microfilled composites and the glass ionomer restorations. The surfaces of the amalgam and gold restorations were altered, but not to the extent that the resin-based materials were. No disruption of the surface characterization of the porcelain was detected; however, with gold and porcelain materials, the aluminum trihydroxide removed notable amounts of the luting cements (the results are consistent with the data gathered with sodium bicarbonate powder). CONCLUSION: Aluminum trihydroxide as the abrasive agent in an airpolishing system should be avoided on resin composites, resin-modified composites, and around the margins of cemented restorations.

The effect of elevated temperatures on the dentin adhesion of resin composites.

Although resin composite restorations may undergo relatively extreme temperature changes in the oral cavity, little is known about the effects of temperature on their adhesion to tooth structure. This study evaluated the effect of temperature on shear bond strength to dentin of three commercial resin dentin adhesives through testing of matured specimens over the 20 degrees to 55 degrees C temperature range. A significant difference (p < 0.05) was observed between 20 degrees C and 55 degrees C for all the materials, and for one of the materials, a significant difference was also observed between 20 degrees C and 37 degrees C.

One-year clinical performance of a self-etching adhesive in class V resin composites cured by two methods.

This study evaluated the clinical performance of a self-etching adhesive for resin composites over one year. Thirty pairs of restorations of Pertac II, using the adhesive Prompt L-Pop, were placed in caries-free cervical erosion/abfraction lesions without tooth preparation. One of each pair was cured using "soft-start" polymerization, while the other was polymerized with high-intensity halogen light. Restorations were clinically evaluated at baseline, six and 12 months using modified Ryge/USPHS criteria. Although no significant difference (p>0.05) was observed between the curing methods, adhesive performance was poor, with a 35% loss of restorations overall.