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Females often possess ornaments that appear smaller and duller than homologous traits in males. These ornaments may arise as nonfunctional by-products of sexual selection in males and cause negative viability or fecundity selection in females in proportion to the cost of their production and maintenance. Alternatively, female ornaments may function as signals of quality that are maintained by sexual or social selection. In a 4-year study of 83 female common yellowthroats (Geothlypis trichas) and their 222 young, we found strong viability and fecundity selection on the yellow bib, a carotenoid-based plumage ornament that is a target of sexual selection in males. Females with larger bibs were older, larger and more fecund than females with smaller bibs. However, bib size positively covaried with bib total brightness and carotenoid chroma, aspects of bib coloration that were under negative viability and fecundity selection. Females with more colourful bibs laid fewer eggs in their first clutch, were more likely to suffer total brood loss due to predation and were less likely to return to the study area. Selection against bib coloration limits the value of bib size as a quality indicator in females and may constrain the elaboration of bib attributes in males.

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PURPOSE: The interactive effects of synthetic polyaramid reinforcement fibers on the transverse strength of intact and repaired heat-polymerized denture base acrylic resins were investigated. MATERIALS AND METHODS: Three polymethylmethacrylate (PMMA) polymers were tested: Acron MC (GC International Corp, Scottsdale, AZ), Lucitone 199 (Dentsply International Inc, York, PA), and Microlon (The Hygienic Corp, Akron, OH). With each polymer, there were 2 controls and 4 experimental groups (n = 9 per group). The treatment groups were intact heat-polymerized PMMA control, PMMA with unreinforced repair, PMMA with polyaramid reinforced repair, intact polyaramid reinforced heat-polymerized PMMA control, polyaramid reinforced PMMA with unreinforced repair, and polyaramid reinforced PMMA with polyaramid reinforced repair. The transverse fracture strengths of the samples were measured with a 3-point bending test on a Zwick Universal Testing Machine (Zwick of America, Inc, East Windsor, CT). RESULTS: The highest mean strength at fracture was recorded with intact polyaramid reinforced heat-polymerized PMMA controls for all resins. Analysis of variance showed significant differences in transverse strength (p < .05) by experimental group, by material, and by interaction of group and material. Tukey HSD (honestly significant difference) Multiple Comparisons Test (alpha = 0.05) showed that intact polyaramid reinforced heat-polymerized PMMA controls were significantly stronger than intact heat-polymerized PMMA controls and all the other treatment groups. Use of polyaramid reinforcement in repair of unreinforced PMMA or polyaramid reinforced PMMA did not result in significantly increased transverse strength. CONCLUSIONS: Polyaramid reinforcement significantly increased the transverse strength of intact heat-polymerized PMMA. Polyaramid fibers did not significantly increase strength to reinforce PMMA repairs.

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PURPOSE: To evaluate the efficacy and tolerability of pioglitazone in combination with a sulfonylurea in the treatment of type 2 diabetes mellitus. SUBJECTS AND METHODS: This 16-week, double-blind study included patients on a stable regimen of a sulfonylurea for > or = 30 days and with a glycosylated hemoglobin (HbA1C) level > or = 8.0%. Patients were randomly assigned to receive once daily pioglitazone 15 mg (n = 184), pioglitazone 30 mg (n = 189), or placebo plus sulfonylurea (n = 187). RESULTS: Patients receiving pioglitazone + sulfonylurea had significant (P < 0.05) decreases from baseline in HbA1C and fasting plasma glucose levels compared with patients treated with placebo + sulfonylurea. As compared with placebo, HbA1C decreased by 0.9% (95% confidence interval [CI]: 0.06% to 1.2%) with pioglitazone 15 mg and 1.3% (CI: 1% to 1.6%) with 30 mg pioglitazone; fasting plasma glucose levels decreased by 39 mg/dL (95% CI: 27 to 52 mg/dL) with pioglitazone 15 mg and by 58 mg/dL (95% CI: 46-70 mg/dL) with 30 mg pioglitazone. Both pioglitazone + sulfonylurea groups had significant (P < 0.05) mean percent decreases in triglyceride levels (17%, 95% CI: 6% to 27% for 15 mg; 26%, 95% CI: 16% to 36% for 30 mg) and increases in high-density lipoprotein cholesterol levels (6%, 95% CI: 1% to 11% for 15 mg; 13%, CI: 8% to 18% for 30 mg) compared with placebo + sulfonylurea. There were small but statistically significant mean percent increases in low-density lipoprotein cholesterol levels in all groups. Pioglitazone was well tolerated, and the rates of adverse events were similar in all groups. CONCLUSION: In patients with type 2 diabetes, pioglitazone plus sulfonylurea significantly improves HbA1C and fasting plasma glucose levels with beneficial effects on serum triglyceride and HDL-cholesterol levels.

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OBJECTIVE: To evaluate the efficacy and safety of four doses of pioglitazone monotherapy in the treatment of patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: There were 408 patients randomized in this multicenter double-blind placebo-controlled clinical trial. Patients who had HbA1c > or = 7.0%, fasting plasma glucose (FPG) > or = 140 mg/dl, and C-peptide > 1 ng/ml were randomized to receive placebo or 7.5, 15, 30, or 45 mg pioglitazone administered once a day for 26 weeks. RESULTS: Patients treated with 15, 30, or 45 mg pioglitazone had significant mean decreases in HbA1c (range -1.00 to -1.60% difference from placebo) and FPG (-39.1 to -65.3 mg/dl difference from placebo). The decreases in FPG were observed as early as the second week of therapy; maximal decreases occurred after 10-14 weeks and were maintained until the end of therapy (week 26). In the 15-, 30-, or 45-mg pioglitazone groups, there were significant mean percent decreases in triglycerides, significant mean percent increases in HDL cholesterol, and only small percent changes in total cholesterol and LDL. The subset of patients naive to therapy had greater improvements in HbA1c and FPG (difference from placebo of -2.55% and -79.9 mg/dl for the 45-mg group) compared with previously treated patients. The overall adverse event profile of pioglitazone was similar to that of placebo. There was no evidence of drug-induced hepatotoxicity or drug-induced elevations of alanine aminotransferase levels in this study CONCLUSIONS: Pioglitazone monotherapy significantly improves HbA1c and FPG while producing beneficial effects on serum lipids in patients with type 2 diabetes with no evidence of drug-induced hepatotoxicity.

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BACKGROUND: Their complimentary mechanisms of action suggest that a combination of pioglitazone hydrochloride and metformin may have clinically beneficial effects in the treatment of patients with type 2 diabetes. OBJECTIVE: This study was undertaken to assess the efficacy and tolerability of pioglitazone in combination with metformin in patients with type 2 diabetes mellitus. METHODS: This was a 16-week, double-blind study with the option of enrollment in a separate open-ended, open-label study. It included patients with poorly controlled diabetes mellitus (glycated hemoglobin [HbA1c] > or =8.0%, fasting C-peptide >1.0 ng/mL) who had been receiving a stable regimen of metformin for > or =30 days. Patients with diabetic retinopathy, nephropathy, or neuropathy; impaired liver or kidney function; or unstable cardiovascular or cerebrovascular conditions were excluded. Patients were randomized to receive once-daily pioglitazone 30 mg + metformin or placebo + metformin. Patients in the open-label extension received pioglitazone 30 mg (with optional titration to 45 mg) + metformin. RESULTS: Three hundred twenty-eight patients were randomized to treatment (168 pioglitazone + metformin, 160 placebo + metformin), and 249 completed the study. Of these, 154 elected to enter the open-label extension study. Patients' mean age was 56 years; most (84%) were white and slightly more than half (57%) were male. Patients receiving piogli- tazone 30 mg + metformin had statistically significant mean decreases in HbA1c (-0.83%) and fasting plasma glucose (FPG) levels (-37.7 mg/dL) compared with placebo + metformin (P < or = 0.05). Decreases in FPG levels occurred as early as the fourth week of therapy, the first time point at which FPG was measured. The pioglitazone + metformin group had significant mean percentage changes in levels of triglycerides (-18.2%) and high-density lipoprotein cholesterol (+8.7%) compared with placebo + metformin (P < or = 0.05). Mean percentage increases were noted in low-density lipoprotein cholesterol levels (7.7%, pioglitazone + metformin; 11.9%, placebo + metformin) and total cholesterol (4.1%, pioglitazone + metformin; 1.1%, placebo + metformin), with no significant differences between groups. In the extension study, patients treated with open-label pioglitazone + metformin for 72 weeks had mean changes from baseline of -1.36% in HbA1c and -63.0 mg/dL in FPG. The incidence of adverse events was similar in both groups. Throughout the study, no patient in either treatment group had an alanine aminotransferase (ALT) value > or =3 times the upper limit of normal, a commonly used marker of potential liver damage. Thus, no evidence of drug-induced hepatotoxicity or drug-induced elevations in serum ALT was observed. CONCLUSIONS: In this study in patients with type 2 diabetes mellitus, pioglitazone + metformin significantly improved HbA1c and FPG levels, with positive effects on serum lipid levels and no evidence of drug-induced hepatotoxicity. These effects were maintained for >1.5 years, including the open-label extension.

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Polymethyl methacrylate exhibits excellent physical properties. Unfortunately, complete dentures fabricated from this material may still fracture. Maxillary complete dentures opposing natural dentition may have a tendency to develop recurrent midline fractures due to multiple reasons. A potential method of preventing this fracture is metal reinforcement of the palatal portion of the prosthesis. A technique will be presented describing a sequence that incorporates predictable design, fabrication and finishing of a metal palate for a maxillary complete denture.

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PURPOSE: This paper reviews the literature on advanced strategies that attempt to improve fit in implant prosthodontics with reference to the concept of the "distortion equation." MATERIALS AND METHODS: The majority of the articles reviewed were either clinical or technique articles that advocated strategies to improve fit in implant prosthodontics. A limited number of retrospective and prospective clinical trial studies were included as they related to the topic. Reviewed articles were limited to those that addressed advanced strategies to improve fit. All of the scientific studies included in this review used an in vitro experimental design. The advanced strategies were categorized into methods that address intraoral indexing and methods that use the implant master cast. RESULTS: Relatively few methods have been scientifically proven to improve fit in implant prosthodontics. Most of the tested strategies still resulted in a slight misfit of the frameworks to the implant abutments/analogues. CONCLUSION: Multiple factors preclude that the concept of "passive fit" can be achieved in implant prosthodontics, even with the use of advanced strategies. The use of meticulous, accurate implant prosthodontic procedures and the appropriate use of advanced strategies continue to be the recommended means of achieving precise fit of the implant prosthesis to the intraoral abutments.

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STATEMENT OF PROBLEM: Low fusing alloy has been used in dentistry for remount procedures in both fixed and removable prosthodontics, in implant prosthodontics for the fabrication of solid implant casts, in maxillofacial prosthetics as oral radiation shields, and in dental research for its unique properties. Previously, the use of low fusing alloy was thought to offer a high degree of dimensional accuracy. However, multiple in vitro studies have shown that its presumed dimensional accuracy may be questionable. PURPOSE: This article reviews the physical properties, metallurgical considerations of low fusing alloy, its applications in dentistry, and a safe, simple method of using low fusing alloy.

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PURPOSE: Materials used to fabricate the most dimensionally accurate implant casts have not been identified experimentally. The purpose of this investigation was to examine the dimensional accuracy of implant casts fabricated with different materials. Measurements of linear horizontal dimensional change and strain produced on a master framework were evaluated and correlated. MATERIALS AND METHODS: A master framework was fabricated to fit an aluminum five-implant model. Forty polyether implant impressions of the aluminium model were randomly grouped and poured in either Vel-mix, Die Keen, Resin Rock, or Low Fusing Alloy. A digital veneer caliper was used to measure linear distance between the most distal abutments on each of the experimental implant casts and the master model. In addition, strain values were recorded from strain gauges bonded in the mesiodistal axis of the framework, which was secured by prosthetic retaining screws torqued to 10 Ncm. RESULTS: A one-way ANOVA showed a significant difference among the four die materials in dimensional change of the experimental casts (p = .0001). A post-hoc Duncan's multiple-range test (p < .05) showed that casts fabricated with Low Fusing Alloy had the least linear dimensional change from the master cast, but the material exhibited the greatest dimensional variability. A MANOVA (Wilks' Lambda) showed significant differences in strain on the framework based upon die material (p = .015). A post-hoc Duncan's multiple-range test (p < .05) showed that Resin Rock casts induced significantly less strain on the framework than the other materials. Negligible correlation was found between the linear horizontal dimensional change and the total absolute strain on the framework. CONCLUSION: Experimental implant casts made of Resin Rock minimized strain on the master framework and decreased the amount of framework distortion on casts of this material. Low Fusing Alloy yielded accurate casts, but highly variable linear dimensional changes in the horizontal dimension may preclude its clinical benefit.

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The restoration of patients with dental implants presents many challenges. Some of the common concerns and problems are difficulty in achieving a passive-fitting cast framework and loosening of prosthesis-retraining screws or abutment screws when using external hex prosthesis connection systems. The ITI system uses a unique connection of the abutment to the prosthesis-anchoring component. Because of this unique connection, many problems encountered with external hex designs have been greatly reduced or eliminated by the ability to more easily restore individual teeth with individual implants. This article will present the rationale for restoration of a patient with implants using individual implant-supported restorations.

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An important factor that affects the clinical success of dental implants is the way stresses are transferred to the bone via the implant framework and fixture. An ill-fitting implant framework will contribute to these stresses and may result in catastrophic failure of the prosthesis or one of the components and/or fixtures, in addition to possible alveolar bone loss. Many factors may contribute to the difficulty of achieving a passive fit on a complete-arch implant framework. A technique for producing an accurate master cast by using a low-fusing metal is described. The low-fusing metal is dimensionally more accurate than conventional gypsum products. The technique does not require a significant change from conventional chairside and laboratory procedures for complete-arch master cast impressions, and should result in a more passively fitting framework.

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With increases in the number of older persons in our society, especially in the ranks of the oldest-old, practitioners in long-term-care settings will be faced with greater numbers and more complex issues in the nursing home admission process. This article discusses and includes case examples of some of the major problems involved in nursing home admission. Furthermore, the article proposes a clinical model which helps practitioners identify and organize information about admissions to select an appropriate course of action.

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Board certification in any health care-related area is one mechanism that promotes high standards of practice and assures public confidence. Certification eligibility and requirements for dental technicians and laboratories are reviewed. Issues affecting the future of dental technology are discussed.

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An accelerated method of using a light-cured acrylic resin and rapid burnout for casting a direct-pattern post and core restoration is presented. Light-cured acrylic resins are an alternative to chemically cured acrylic resins or indirect patterns formed from an elastomeric impression. The procedure can eliminate an appointment for the patient in the fabrication of the post and core restoration and can be completed in most dental offices with minimal laboratory facilities. Chair-side time is saved because of the elimination of one provisional restoration when two are usually required. Laboratory time is also saved because of the decrease in investment setting and burnout time.

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This study describes the casualties referred during the Persian Gulf War and underscores the valuable role of Army physical medicine and rehabilitation (PMR) services in evaluation and early rehabilitation of wartime casualties. Data regarding demographics, injury types, medical complications, complications of immobility and functional limitations were collected by military physiatrists at five Army Medical Centers with PMR services. Active duty soldiers injured in the Persian Gulf War who were referred totalled 222. Musculoskeletal injuries occurred in 57%, peripheral nerve injuries in 44%, penetrating wounds in 32%, fractures in 28%, brain injuries in 8%, amputations in 7%, burns in 6% and spinal cord injuries in 3%. The primary referral service was orthopedics (64%). Electrodiagnosis evaluations were performed for 41% of all referrals. Lower limb and upper limb contractures occurred in 10% and 9% of patients, respectively. Ambulatory impairments were seen in 48%. Nerve injuries were associated with penetrating wounds in 68%, with amputations in 67% and with fractures in 58%.

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This study compared the effects of various rotary instruments and polishing agents on tooth enamel. Topographical features of enamel were studied at consecutive stages of polishing with photoanalysis of scanning electron micrographs. The results indicate that enamel modified by diamond burs may be polished to produce the smoothest surface with white finishing stones, Ceramist finishing points, and flour of pumice.

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