bluuebunny/crossref_metadata_2025 huggingface dataset:
Desperately Seeking Regulatory Impact Assessments
Authors: Radaelli Claudio M.
Published: January 2009

This article provides some reflective thoughts on current research on regulatory impact assessment (RIA) in Europe.The narrative draws on the author's fieldwork diaries. It starts from the methodological problems of identifying and analysing regulatory impact assessment in the UK, Denmark, the Netherlands and Sweden.This leads to more fundamental theoretical questions about research design, the relationship between supply and demand of research and, ultimately, the aims of academic research in this area.The conclusions draw lessons for the emerging research agenda on better regulation.The main problem is not whether `real' RIAs exist or not, since this would be equivalent to trying to fit the amoeba-like RIA `substance' into our abstract`forms'.The interesting problems are: what are the functions of different approaches to assessment, how are they used and how can they improve governance?
Testing Methodological Guidance on the Conduct of Narrative Synthesis in Systematic Reviews
Authors: Rodgers Mark , Sowden Amanda , Petticrew Mark , Arai Lisa , Roberts Helen , Britten Nicky , Popay Jennie
Published: January 2009

The objective was to assess the impact of new guidance on the conduct of narrative synthesis in systematic reviews of effectiveness, by means of a blinded comparison of guidance-led narrative synthesis against a meta-analysis of the same study data.The conclusions of the two syntheses were broadly similar. However, differences between the approaches meant that conclusions about the impact of moderators of effect appeared stronger when derived from the meta-analysis, whereas implications for future research appeared more extensive when derived from the narrative synthesis. These findings emphasize that a rigorously conducted narrative synthesis can add meaning and value to the findings of meta-analysis.The guidance framework provided a useful vehicle for structuring a narrative synthesis and increasing transparency and rigour of the process.While there may be risks with overinterpretation of study data, the framework, tools and techniques described in the guidance appear to increase the transparency and reproducibility of narrative synthesis.
Cooperation Networks and Innovation
Authors: Russo Margherita , Rossi Federica
Published: January 2009

Recent developments in innovation theory and policy have led policy makers to assign particular importance to supporting networks of cooperation among heterogeneous economic actors, especially in production systems composed of small and medium enterprises. Such innovative policies call for parallel innovations in policy analysis, monitoring and assessment. Our analysis of a policy experiment aimed at supporting innovation networks in the Italian region of Tuscany intends to address some issues connected with the design, monitoring and evaluation of such interventions. Combining tools from ethnographic research and social networks analysis, the article explores the structural elements of the policy programme, its macroscopic impact on the regional innovation system and the success of individual networks in attaining their specific objectives.This innovative approach allows us to derive some general methodological suggestions for the design and evaluation of similar programmes.
Empowering Programs With Evaluation Technical Assistance
Authors: Gibbs Deborah A. , Hawkins Stephanie R. , Clinton-Sherrod A. Monique , Noonan Rita K.
Published: January 2009

Although empowerment evaluation has gained widespread currency, few reports have described its outcomes. This article combines perspectives of participants and technical assistance providers to describe the process and outcomes of the Evaluation Assistance for Sexual Violence Programs project. Participating programs reported substantial enhancements in evaluation capacity, resources devoted to evaluation, and the extent and sophistication of their evaluation practice, as well as numerous examples of the application of evaluation findings to program improvement. Experiences from evaluation technical assistance providers identified aspects of the process that were particularly useful in achieving these outcomes, including investing in collaborative relationships, maximizing participation among program staff, tailoring the content and form of technical assistance to program preferences, and combining structured learning with program-specific technical assistance.
Process Evaluation and Participatory Methods in an Obesity-Prevention Media Campaign for Mexican Americans
Authors: Reininger Belinda M. , Barroso Cristina S. , Mitchell-Bennett Lisa , Cantu Ethel , Fernandez Maria E. , Gonzalez Dora Alicia , Chavez Marge , Freeberg Diamantina , McAlister Alfred
Published: January 2009

To address obesity and related morbidities, community-based participatory research (CBPR) strategies were employed to design and evaluate a Spanish-language media campaign promoting physical activity and healthful food choices among Mexican Americans. Process evaluation including content analyses on types and focus of media messages was conducted. Focus groups assessed appeal and trustworthiness of messages. All media campaign products featured role models and experts. Campaign messages primarily (91%) appeared in TV morning show segments. Newsletters presented individual and family role model stories. A majority of newsletters (68%) were distributed through churches and “promotora” outreach efforts. CBPR lends itself to the selection and tailoring of evidence-based media campaigns. Moreover, CBPR guidance resulted in media messages that were credible and appealing to audience. Process evaluation strategies that gather information from the community provide solid evidence for how to modify the campaign to best meet audience expectations.
Adoption, Adaptation, and Fidelity of Implementation of Sexual Violence Prevention Programs
Authors: Noonan Rita K. , Emshoff James G. , Mooss Angela , Armstrong Michael , Weinberg Joanna , Ball Barbara
Published: January 2009

Little research examines the organizational and contextual dynamics that affect decisions to adopt evidence-based programs as well as the feasibility of implementation with fidelity to the original model when new users adopt established programs. To understand how promising strategies can be disseminated widely, this study examines the adoption and implementation of two sexual violence prevention programs in new settings. Interviews were conducted with stake-holders to investigate the factors and dynamics related to the adoption and implementation of these programs. Additionally, the research team worked with the program developers to create measures of the fidelity of implementation, which were then administered at each site. The findings suggest that adoption decisions were based on perceived fit between the program and the adopting organization's values, goals, and local setting. After adoption, new sites were able to implement the program with fairly high levels of fidelity, given moderate investments in training and technical assistance.
Proinflammatory and Anti-inflammatory Cytokine Balance in Patients With Abdominal Aortic Aneurysm and the Impact of Aneurysm Size
Authors: Wallinder Jonas , Bergqvist David , Henriksson Anders E.
Published: January 2009

Abdominal aortic aneurysm is a common condition with high mortality due to rupture; however, the condition also is associated with nonaneurysmal cardiovascular mortality. A possible contributing mechanism for the cardiovascular mortality is an imbalance between the proinflammatory and anti-inflammatory systemic response. In the present study, 78 patients with abdominal aortic aneurysm and 41 controls without aneurysm matched by age, gender and smoking habits were investigated. Cytokines such as interleukin-6, interleukin-10, and monocyte chemoattractant protein-1 were measured in plasma. There was significantly higher level of interleukin-6 in patients with AAA compared to controls. The interleukin-6/ interleukin-10 ratio was highest in patients with large compared to small abdominal aortic aneurysm. In conclusion, the present data indicate a proinflammatory response and a proinflammatory to antiinflammatory imbalance in patients with abdominal aortic aneurysm which is dependent by aneurysm size.
Venous Outflow Obstruction With Retroperitoneal Kaposi's Sarcoma and Treatment With Inferior Vena Cava Stenting
Authors: Gasparis Antonios P. , Kokkosis Angela , Labropoulos Nicos , Tassiopoulos Apostolos K. , Ricotta John J.
Published: January 2009

A 26-year-old man presented with acute renal insufficiency, and severe lower extremity swelling. Computed tomographic scan revealed retroperitoneal lymphadenopathy encasing both ureters and the inferior vena cava. He underwent placement of ureteral stents to relieve the obstruction and afterward underwent lymph node biopsy, which revealed Kaposi's sarcoma. He subsequently was diagnosed with acquired immunodeficiency syndrome. Abdominal and lower extremity venous duplex ultrasound did not show any evidence of deep vein thrombosis. The inferior vena cava measured 3.5 mm in diameter and was encased by retroperitoneal lymphadenopathy. Bilateral transfemoral venography and intravascular ultrasound demonstrated significant compression of the inferior vena cava below the renal veins. Endovascular treatment was followed with primary stenting under intravascular ultrasound guidance. His symptoms improved with reduction in swelling. At 1-year follow-up, the patient was ambulatory with mild symptoms, and on venography the iliac vein and inferior vena cava stents were widely patent.
Endovascular Repair of Innominate Artery Injury Secondary to Air Rifle Pellet: A Case Report and Review of the Literature
Authors: Gifford Shaun M. , Deel John T. , Dent Daniel L. , Seenu Reddy V. , Rasmussen Todd E.
Published: January 2009

Objective: Decreased morbidity makes endovascular treatment preferable for certain central aortic and great vessel injuries. We present a case of penetrating innominate injury, describe considerations of a catheter-based approach, and provide follow-up of repair. Methods: A case report and review of the literature. Results: A 16-year-old man presented with an isolated innominate artery injury following an air rifle wound. Standard transfemoral approach was used to gain access the innominate artery. The injury was treated with an 8 × 35 mm, balloon-expandable, covered stent. Completion imaging confirmed a well-positioned stent with exclusion of the injury and normal flow in distal vessels. There were no symptoms of stent migration or stenosis 1 year following the injury. Conclusions: Specific anatomic characteristics including its proximity to the carotid and vertebral arteries make the endovascular approach to the innominate artery unique. This case demonstrates the viability of catheter-based approaches in treating vascular injury.
Has the Implementation of EVAR for Ruptured AAA Improved Outcomes?
Authors: Vogel Todd R. , Dombrovskiy Viktor Y. , Haser Paul B. , Graham Alan M.
Published: January 2009

Objective: Previous studies have demonstrated improved outcomes with Endovascular Aneurysm Repair (EVAR) for the treatment of ruptured abdominal aortic aneurysms (rAAA). However, these data may not be generalizable to all regions.

Methods: Retrospective cohort study (2001-2005) using state inpatient data.

Results: 5,176 patients underwent repair of AAA. 700 repairs were performed for rAAA (618 [88%] with open surgery (OS) and 82 [12%] with EVAR). Mortality for rAAA was similar for EVAR and OS (45.1% vs. 52.4%, P = 0.21). Lack of insurance (OR = 5.1; 95%CI: 1.7-15.2) was a predictor of mortality. Cost of repair for rAAA was greater for EVAR ($51,339 ± 51,719 vs. $39,967 ± 43,354, P = 0.03) and hospital LOS was similar (14.08 ± 17.97 vs.13.42 ± 18.18; P = 0.8). Conclusion: EVAR did not offer a survival benefit in the state, had a similar hospital LOS, and was significantly more expensive. Further evaluation exploring explanations for inferior outcomes by region are required as EVAR becomes more commonly implemented for rAAA.
Molecular Cloning of Wound Inducible Transcript (wit 3.0) Differentially Expressed in Edentulous Oral Mucosa Undergoing Tooth Extraction Wound-healing
Authors: Sukotjo C. , Abanmy A.A. , Ogawa T. , Nishimura I.
Published: January 2009

Tooth extraction is the most commonly prescribed ablation surgery in dentistry and results in the formation of edentulous mucosa. Although the edentulous mucosa serves as the critical interfacial tissue for removable and implant-assisted prostheses, the structure and physiology of this wound-induced tissue are largely uninvestigated. We addressed the hypothesis that tooth extraction activates the expression of a unique set of genes in healing edentulous mucosa. Using the Differential Display Polymerase Chain Reaction and 5′ Rapid Amplification of cDNA Ends protocols, we isolated overlapping cDNAs encoding a 3.0-kb-long mRNA, Wound Inducible Transcript, 3.0 ( wit 3.0). In situ hybridization demonstrated that wit 3.0 was primarily expressed by the fibroblasts associated with tooth extraction wound-healing. Appearing to generate from the wit 3.0 gene, two alternative transcripts presented, encoding 215-( wit 3.0 α) and 253-( wit 3.0 β) amino-acid-long peptides with the characteristics of an intracellular molecule. Analysis of these data may provide new clues to the molecular mechanism of edentulous mucosa formation.
Effects of Excitatory Amino Acid Receptor Antagonists on Pulpal Blood Flow of the Rat Mandibular Incisor
Authors: Hofman S. , Azérad J. , Boucher Y.
Published: January 2009

Pulpal blood flow (PBF) changes have been monitored by laser Doppler flowmetry on rat mandibular incisors. Electrical stimulation (10 sec, 50 μA, 2 ms, 20 Hz) of one incisor induced a blood flow decrease followed by a blood flow increase. The effect of intravenous administration of antagonists of ionotropic glutamate receptors (iGluRs) and antagonists of metabotropic glutamate receptors (mGluRs) was compared with that of those obtained from animals treated with the vehicle alone. No long-term effect on basal PBF was observed, except a remaining increase of 34.5% (p < 0.05, n = 5) for ketamine (10 mg/kg), an iGluR antagonist, and of 37% (p < 0.05, n = 5) for MCPG (7.5 mg/kg), an mGluR antagonist. In animals treated with iGluR antagonists, acute changes in PBF after stimulation were not significantly different from those observed with vehicle. In animals treated with mGluR antagonists, the blood flow decrease was significantly enhanced in amplitude and duration for MCPG (7.5 mg/kg), respectively, +73% and +92% (p < 0.05, n = 5). These results suggest that Group I mGluRs participate in the regulation of the immediate pulpal blood flow decrease induced by electrical stimulation of the lower incisor in the rat.
Parotid Gland Function and Dentin Apposition in Rat Molars
Authors: Leonora J. , Tjäderhane L. , Tieche J.-M.
Published: January 2009

Previous studies have clearly established the down-regulating effect of a sucrose-rich diet on primary dentinogenesis in rat molars. Earlier observation of the negative effect of a high-sucrose diet on a parotid function involved in the control of intradentinal solute movement led us to hypothesize that parotid gland function(s) may have a role in regulating dentinogenesis. Dentin apposition in 1st and 2nd molars of young rats was measured by planimetry in sagittal sections. The following experimental variables were tested: standard and high-sucrose diets, removal of the parotid or the submandibular/sublingual glands, and diets in powder or pellet form. Removal of the submandibular/sublingual glands and changes in diet consistency did not significantly affect dentin apposition. Dentin apposition was significantly depressed by the high-sucrose diet or following parotidectomy. A further decrease followed the combination of the two treatments. Parotid glands appeared to exert a positive effect on dentin apposition in rat molars.
Improved Filler-Matrix Coupling in Resin Composites
Authors: Yoshida Y. , Shirai K. , Nakayama Y. , Itoh M. , Okazaki M. , Shintani H. , Inoue S. , Lambrechts P. , Vanherle G. , Van Meerbeek B.
Published: January 2009

Ineffective silane coupling between filler and matrix within dental composites is prone to accelerated in vivo degradation. In this study, we examined to what degree a procedure involving chemical decontamination of filler prior to silanization could improve the filler-matrix bonding, and thus the physico-mechanical properties, of composites. X-ray photoelectron spectroscopy revealed that filler-matrix coupling largely depended upon siloxane bridge (Si-O-Si) formation between the silica surface and the silane molecule, rather than on intermolecular bonding between adjacent silane molecules. Pre-silanization decontamination based upon boiling silica in 0.05-5% sodium peroxodisulfate, followed by ultrasonic rinsing in acetone, most effectively decontaminated filler. Consequently, it significantly improved the bonding of silane molecules to silanol groups at the silica surface. Experimental composites produced following pre-silanization decontamination of filler revealed a diametral tensile strength that was resistant to degradation by thermocycling.
Maternal Periodontal Disease and Preterm Low Birthweight: Case-Control Study
Authors: Davenport E.S. , Williams C.E.C.S. , Sterne J.A.C. , Murad S. , Sivapathasundram V. , Curtis M.A.
Published: January 2009

Periodontal disease has been suggested to be an important risk factor for preterm low birthweight (PLBW). Here we report a case-control study of 236 cases (infants < 37 wks and weighing < 2499 g) and a daily random sample of 507 controls (≥ 38 wks and weighing ≥ 2500 g). Clinical periodontal indices were measured on the labor wards. Associated risk factors for periodontal disease and PLBW were ascertained by means of a structured questionnaire and maternity notes. The risk for PLBW decreased with increasing pocket depth (odds ratio [OR] 0.83, 95% confidence interval [CI] 0.68 to 1.00). After adjustment for maternal age, ethnicity, maternal education, smoking, alcohol consumption, infections, and hypertension during pregnancy, this decreased further (OR 0.78, 95% CI 0.64 to 0.99). We found no evidence for an association between PLBW and periodontal disease. Our results do not support a specific drive to improve periodontal health of pregnant women as a means of improving pregnancy outcomes.
The Importance of the Level of the Lip Line and Resting Lip Pressure in Class II, Division 2 Malocclusion
Authors: Lapatki B.G. , Mager A.S. , Schulte-Moenting J. , Jonas I.E.
Published: January 2009

Many clinicians hypothesize that retroclination of the maxillary central incisors in Class II, Division 2 malocclusion is caused by increased resting lip pressure against these teeth. The purpose of this study was (1) to verify this assumption by means of simultaneous lip-pressure measurements at two different levels on the maxillary central incisor crowns, and (2) to examine factors that could possibly contribute to the increased resting lip pressure. This is the first study to prove that individuals with Class II, Division 2 malocclusion (n = 21) have the upper central incisors exposed to significantly higher lip pressure than those with Class I malocclusion (n = 21). Our statistical evaluation revealed that this is primarily attributed to a high lip line and not to a hypertonic peri-oral musculature. We concluded that orthodontic treatment of Class II, Division 2 cases should include intrusion of the maxillary incisors, to eliminate the non-physiologically high pressure exerted by the lower lip on these teeth and, consequently, to reduce the high risk of a post-orthodontic relapse.
Comparative Microstructural Study of the Diffusion Zone between NiCr Alloy and Different Dental Ceramics
Authors: Hegedu�s C. , Daróczi L. , Kökényesi V. , Beke D.L.
Published: January 2009

Our knowledge on the bonding mechanisms between the metal and ceramic parts of dental systems is very limited. This work tested the hypothesis that the details of the interface processes can be described in the framework of a chemical diffusion model. The development of interfacial phases was investigated by cross-sectional analytical transmission electron microscopy between a NiCr (Wiron 99) alloy and three different dental ceramics (Carat, Vita VMK 95, and Vision). All systems were investigated at normal firing conditions (suggested by the manufacturer) and at increased firing times as well. The conclusions are based on the results that the formation of a nanocrystalline Cr2O3 layer and amorphous silicon oxide inclusions were detected in the early stage of the firing process in all investigated systems, and that, in the case of Carat and Vision ceramics, formation of complex NiCr and NiCrTi oxides was also observed at longer annealing times.

It is shown by transmission electron microscopy that, in the reaction processes taking place at the NiCr alloy/dental ceramics interface, nanocrystalline Cr2O3 first forms and amorphous silicon oxide inclusions appear, then, at longer firing times, complex NiCr and NiCrTi oxides form.
Helical Axis Errors Affect Computer-generated Occlusal Contacts
Authors: DeLong R. , Ko C.-C. , Olson I. , Hodges J.S. , Douglas W.H.
Published: January 2009

A helical axis describing mandibular motion can be calculated from two distinct positions of the mandible; however, as these positions come closer together, calculation errors increase. This study investigated the effects of errors in the calculated helical axis on simulated mandibular motion by the measurement of changes in occlusal contacts. A standard helical axis was calculated from a simulated lateral movement. A series of digital interocclusal records from centric to a 5° mandibular rotation about the standard helical axis was created. Digital dental cast models were aligned to the interocclusal records. Helical axis parameters and occlusal contacts calculated with the use of the aligned digital models were compared with those of the standard. Helical axes calculated from mandibular positions separated by 1.5° to 5.0° yielded equivalent occlusal contacts. Qualitatively, contacts for helical axes calculated from jaw rotations of 0.7° or larger were nearly identical to those of the standard.
Regulation and Interactions of MT1-MMP and MMP-20 in Human Odontoblasts and Pulp Tissue in vitro
Authors: Palosaari H. , Ding Y. , Larmas M. , Sorsa T. , Bartlett J.D. , Salo T. , Tjäderhane L.
Published: January 2009

MT1-MMP is a cell-membrane-bound metalloenzyme that activates other proMMPs such as proMMP-2 and -13. We studied MT1-MMP expression in mature human odontoblasts and pulp tissue, the regulation of MT1-MMP expression by growth factors TGF-β1 and BMP-2, and the activation of odontoblast-derived MMP-20 by MT1-MMP. MT1-MMP mRNA is expressed by native and cultured mature human odontoblasts and pulp tissue. Western blot analysis of human odontoblasts and pulp tissue detects 65- and 51-kDa pro- and active forms of MT1-MMP, and smaller truncated MT1-MMP forms. BMP-2 down-regulates MT1-MMP expression in odontoblasts and pulp tissue, while TGF-β1, alone or with BMP-2, decreases MT1-MMP mRNA levels only slightly. We also demonstrate that MT1-MMP is capable of converting proMMP-20 into a form corresponding to the active MMP-20. In conclusion, this study demonstrates the expression and differential regulation of MT1-MMP in human dentin-pulp complex cells, and the activation of MMP-20 by MT1-MMP.
Interferon-gamma Deficiency Attenuates Local P. gingivalis-induced Inflammation
Authors: Houri-Haddad Y. , Soskolne W.A. , Shai E. , Palmon A. , Shapira L.
Published: January 2009

Infection with the periodontal pathogen Porphyromonas gingivalis causes a strong local inflammatory reaction. Using IFNγ-deficient mice, we tested the hypothesis that the absence of IFNγ would result in a reduction of the local pro-inflammatory response to P. gingivalis. Cytokine secretion by macrophages from IFNγ-/- animals was significantly attenuated. Addition of IFNγ restored cytokine secretion. In vivo injection of P. gingivalis into subcutaneous chambers increased the intra-chamber leukocyte counts and TNFα and IL-1β levels. This increase was significantly lower in the IFNγ-/- mice. Local reconstitution of IFNγ-/- mice at the site of inflammation with the IFNγ gene increased the levels of TNFα and decreased the IL-10 levels. Anti- P. gingivalis IgG1 levels, a marker of Th2 response, were higher in immunized IFNγ-/- than in IFNγ+/+ mice. The results suggest that lack of IFNγ reduced the amplitude of the local pro-inflammatory response without decreasing the humoral protective response. The higher IgG1/IgG2a ratio observed supports the possibility of a Th2-dominant response in IFNγ-deficient animals.
Estrous-cycle-dependent Variation in Orthodontic Tooth Movement
Authors: Haruyama N. , Igarashi K. , Saeki S. , Otsuka-Isoya M. , Shinoda H. , Mitani H.
Published: January 2009

Sex hormones, including estradiol, play important physiological roles in bone metabolism. The purpose of this study was to investigate whether there is estrous-cycle-dependent variation in orthodontic tooth movement, and, if so, to determine the mechanism. Ten-week-old female Wistar rats were used. They received repeated orthodontic force during specific phases in the estrous cycle. Tooth movement in animals that received force principally in estrus was about 33% greater than that in animals that received such force principally in pro-estrus (p < 0.05). Serum estradiol levels also varied according to the estrous cycle, with a peak during pro-estrus and a nadir during estrus, and were inversely related to tooth movement. Furthermore, there were negative correlations between estradiol and both serum TRAP activity and pyridinoline (r = -0.42, p < 0.05; r = -0.59, p < 0.001). These results suggest that cyclic changes in the estradiol level may be associated with the estrous-cycle-dependent variation in tooth movement through its effects on bone resorption.
Roles of Salivary Proteins in the Adherence of Oral Streptococci to Various Orthodontic Brackets
Authors: Ahn S.-J. , Kho H.-S. , Lee S.-W. , Nahm D.-S.
Published: January 2009

Knowledge of salivary pellicles on orthodontic brackets provides a better understanding of microbial adherence. The aim of this study was to analyze the effects of bracket pellicles on the adherence of Streptococcus gordonii and Streptococcus mutans. Bracket pellicles were formed by the incubation of 4 kinds of orthodontic brackets with unstimulated whole saliva for 2 hrs, and analyzed by electrophoresis, immunodetection, and amino acid analysis. Binding assays were then performed by the incubation of tritium-labeled streptococci with the pellicle-transfer blots and orthodontic brackets. The results showed that low-molecular-weight mucin, α-amylase, secretory IgA, acidic proline-rich proteins, and cystatins adhered to all kinds of brackets, though the amino acid composition of pellicles differed between bracket types. Some of these proteins increased the binding of S. gordonii to saliva-coated brackets. However, salivary pellicles decreased the binding of S. mutans. Collectively, salivary pellicles were found to play a significant role in the initial adhesion of oral streptococci to orthodontic brackets.
Salivary Defense Factors in Herpes Simplex Virus Infection
Authors: Välimaa H. , Waris M. , Hukkanen V. , Blankenvoorde M.F.J. , Nieuw Amerongen A.V. , Tenovuo J.
Published: January 2009

Saliva may contribute to a lowering of the infectious herpes simplex virus (HSV) dose during transmission and consequently abrogate infection or lead to decreased reactivation. To test this hypothesis, we assayed saliva for innate defense factors, immunoglobulin content, and the capacity to interfere with HSV infection. Serum or salivary anti-HSV IgG levels did not correlate with control of recurrent labial herpes (RLH) and were significantly higher in subjects with RLH compared with asymptomatic seropositive subjects. Although no differences in levels or output rate of innate defense factors between the groups were observed, the salivary neutralizing activity correlated with lactoferrin and hypothiocyanite concentrations in the asymptomatic seropositive group. Our results suggest that saliva contains factors, in addition to anti-HSV immunoglobulins, that neutralize HSV and may indirectly contribute to the control of RLH.
Caries Rates Related to Approximal Caries at Ages 11-13: A 10-year Follow-up Study in Sweden
Authors: Stenlund H. , Mejàre I. , Källestål C.
Published: January 2009

Predicting future caries risk is a difficult but important clinical task. The aim of this study was to analyze radiographically the relationship between approximal caries (4d-7m) at ages 11-13 (baseline) and future approximal caries. We followed 534 individuals prospectively through annual bitewing radiographs from 11 to 22 years of age. Two measures were used: individual-based incidence of the first new approximal caries lesion and surface-based incidence of approximal lesions. In the group with no approximal caries lesions at baseline, the individual-based incidence was 19 first new approximal lesions/100 person-years; the corresponding value for those with 3 approximal lesions at baseline was 71. Individuals with no approximal lesions at baseline developed 3.1 new lesions/100 tooth surface-years; the corresponding value for those with 3 lesions at baseline was 7.7. The highest risk for developing new approximal lesions was within the first 2 years after baseline.
Enhanced Hydrolytic Stability of Dental Composites by Use of Fluoroalkyltrimethoxysilanes
Authors: Nihei T. , Kurata S. , Kondo Y. , Umemoto K. , Yoshino N. , Teranaka T.
Published: January 2009

The hydrolytic stability of a group of experimental composite materials was evaluated. Seven distinct composites were formed by the mixing of a resin monomer mixture with silica filler that had been pre-treated with one of 7 different ethanol solutions. In one case, the filler was treated with an ethanol solution that contained only 3-methacryloyloxypropyltrimethoxysilane. In 5 cases, it was treated with solution containing a mixture of 3-methacryloyloxypropyltrimethoxysilane and one of the following hydrophobic fluoroalkyltrimethoxysilanes: trifluoropropyl-, nonafluorohexyl-, tridecafluorooctyl-, heptadecafluorodecyl-, and henicosafluorododecyl-trimethoxysilane. The tensile strength, after being immersed in water for 1800 days, of 2 of the experimental composites, whose pre-treatment regimen had included a fluoroalkyltrimethoxysilane, was significantly higher than that of the composite whose pre-treatment regimen had not included a fluoroalkyltrimethoxysilane. Moreover, there was no significant difference between the tensile strength of fresh samples of these 2 composites and the tensile strength of identically produced samples that had remained under water for 1800 days or that had been subjected to 30,000 cycles of thermal stress.
Gene Expression Profiling of Ameloblastoma and Human Tooth Germ by Means of a cDNA Microarray
Authors: Heikinheimo K. , Jee K.J. , Niini T. , Aalto Y. , Happonen R.-P. , Leivo I. , Knuutila S.
Published: January 2009

The molecular and genetic characteristics of ameloblastoma are still poorly understood. We analyzed gene expression in fresh-frozen ameloblastomas and human fetal tooth germs, using a cDNA microarray. Thirty-four genes exhibited significant changes in expression levels in the ameloblastoma. Eleven genes were overexpressed more than three-fold, and 23 genes were underexpressed to below 0.4 of the control level. The oncogene FOS was the most overexpressed gene (from eight- to 14-fold), followed by tumor-necrosis-factor-receptor 1 ( TNFRSF1A). Genes for sonic hedgehog ( SHH), TNF-receptor-associated-factor 3 ( TRAF3), rhoGTP-ase-activating protein 4 ( ARHGAP4), deleted in colorectal carcinoma ( DCC), cadherins 12 and 13 ( CDH12 and 13), teratocarcinoma-derived growth-factor-1 ( TDGF1), and transforming growth-factor-ß1 ( TGFB1) were underexpressed in all tumors. In selected genes, a comparison between cDNA microarray and real-time RT-PCR confirmed similar relative gene expression changes. The gene expression profile identifies candidate genes that may be involved in the origination of ameloblastoma and several genes previously unidentified in relation to human tooth development.
The Effect of a High-sucrose Diet on Dentin Formation and Dental Caries in Hyperinsulinemic Rats
Authors: Pekkala E. , Välikangas L. , Puukka M. , Tjäderhane L. , Larmas M.
Published: January 2009

A high-sucrose diet decreases dentin formation and its minerals, but the mechanisms behind the effect are largely unknown. We studied the combined and separate effects of sucrose and insulin on dentin formation and mineral metabolism in growing rats. At weaning, animals were randomized into 4 groups: control/sucrose diets both with and without external insulin (1 U/x 100 g body weight daily). After 4 weeks, we measured areas of dentin formation, numbers and areas of dentinal caries lesions, and serum and urine glucose, insulin, Ca, Na, K, and P. Exogenous insulin increased serum and urine insulin levels and decreased serum glucose level, but did not affect dentin formation or dentinal caries lesion formation or progression. A high-sucrose diet decreased dentin formation independently of insulin. The differences in serum and urine minerals between the groups were minor. The findings confirm that sucrose-diet-induced reduction in dentinogenesis is independent of insulin and loss of minerals in urine.
Immunolocalization of a Human Cementoblastoma-conditioned Medium-derived Protein
Authors: Arzate H. , Jiménez-García L.F. , Álvarez-Pérez M.A. , Landa A. , Bar-Kana I. , Pitaru S.
Published: January 2009

Little is known about the molecular mechanisms that regulate the cementogenesis process, because specific cementum markers are not yet available. To investigate whether a cementoblastoma-conditioned medium-derived protein (CP) could be useful as a cementum biological marker, we studied its expression and distribution in human periodontal tissues, human periodontal ligament, alveolar bone, and cementoblastoma-derived cells. In human periodontal tissues, immunoreactivity to anti-CP was observed throughout the cementoid phase of acellular and cellular cementum, cementoblasts, cementocytes, cells located in the endosteal spaces of human alveolar bone, and in cells in the periodontal ligament located near the blood vessels. Immunopurified CP promoted cell attachment on human periodontal ligament, alveolar bone-derived cells, and gingival fibroblasts. A monoclonal antibody against bovine cementum attachment protein (CAP) cross-reacted with CP. These findings indicate that CP identifies potential cementoblast progenitor cells, is immunologically related to CAP species, and serves as a biological marker for cementum.
Bonding of Self-etch and Total-etch Adhesives to Carious Dentin
Authors: Yoshiyama M. , Tay F.R. , Doi J. , Nishitani Y. , Yamada T. , Itou K. , Carvalho R.M. , Nakajima M. , Pashley D.H.
Published: January 2009

Carious dentin is partially demineralized and contains mineral crystals in the tubules. This may permit the deeper etching of intertubular dentin but prevent resin tag formation during bonding. We hypothesize that resin adhesives will produce lower bond strengths to caries-infected and caries-affected dentin compared with normal dentin. We tested this by measuring the microtensile bond strength of a total-etch adhesive and an experimental self-etching adhesive (ABF) to caries-infected, caries-affected, and sound dentin and by correlating those results with ultrastructural observations. The bond strengths of both adhesives to sound dentin were significantly (p < 0.05) higher than those to caries-affected dentin, which, in turn were significantly (p < 0.05) higher than those to caries-infected dentin. For both adhesives, hybrid layers in caries-affected dentin were thicker but more porous than those in sound dentin. The lower bond strengths may be due to the lower tensile strength of caries-affected dentin. Clinically, this may not be a problem, since such lesions are normally surrounded by normal dentin or enamel.
Risk Factors for Dental Implant Failure: A Strategy for the Analysis of Clustered Failure-time Observations
Authors: Chuang S.K. , Wei L.J. , Douglass C.W. , Dodson T.B.
Published: January 2009

This study’s objective was to identify, in a statistically valid and efficient manner, the risk factors associated with dental implant failure. We hypothesize that factors exist which can be modified by clinicians to enhance outcome. A retrospective cohort study design was used. Cohort members had ≥ one implant placed. Risk factors were classified as demographic, health status, implant-, anatomic-, or prosthetic-specific, and reconstructive variables. The outcome variable was implant failure. The cohort was composed of 677 patients who had 2349 implants placed. Based on the adjusted multivariate model, factors associated with implant failure were tobacco use, implant length, staging, well size, and immediate implants (p ≤ 0.05). In the setting of correlated survival observations, we recommend adjusting for the correlation of the observations to provide statistically valid and efficient results. Three of the identified factors—tobacco use, immediate implants, and implant staging—potentially may be modified to enhance implant survival.
Edentulation Alters Material Properties of Cortical Bone in the Human Mandible
Authors: Schwartz-Dabney C.L. , Dechow P.C.
Published: January 2009

Ridge resorption following edentulation has been documented clinically, but the effects of tooth loss on the material properties of mandibular cortical bone have received little study. Material properties and their structural basis are essential for our understanding of bone quality in the edentulous mandible and are of interest as a tissue-level model for functional adaptation. This study’s aim was to determine material property variability in the edentulous mandible, and to compare it with data from a previous study of dentate mandibles. Forty-four cortical samples were removed from each of 10 adult fresh edentulous mandibles. Cortical thickness and density were measured. Material properties were calculated from ultrasonic velocities. Mandibular cortical bone in the edentulous mandibles differed from that of dentate mandibles in cortical thickness, elastic and shear moduli, anisotropy, and orientation of the axis of maximum stiffness. These results suggest that cortical microstructural changes accompany ridge resorption following edentulation.
Influence of Connector Design on Fracture Probability of Ceramic Fixed-partial Dentures
Authors: Oh W. , Götzen N. , Anusavice K.J.
Published: January 2009

Fracture of ceramic fixed-partial dentures (FPDs) tends to occur in the connector area because of stress concentrations. The objective of this study was to test the hypothesis that the radius of curvature at the gingival embrasure of the FPD connector significantly affects the fracture resistance of three-unit FPDs. Two three-dimensional finite element models (FEMs), representing two FPD connector designs, were created in a manner corresponding to that described in a previous experimental study (Oh, 2002). We performed fractographic analysis and FEM analyses based on CARES (NASA) post-processing software to determine the crack initiation site as well as to predict the characteristic strength, the location of peak stress concentrations, and the risk-of-rupture intensities. A good correlation was found between the experimentally measured failure loads and those predicted by FEM simulation analyses. Fractography revealed fracture initiation at the gingival embrasure, which confirms the numerically predicted fracture initiation site. For the designs tested, the radius of curvature at the gingival embrasure strongly affects the fracture resistance of FPDs.
Comparing the Costs of Three Sealant Delivery Strategies
Authors: Griffin S.O. , Griffin P.M. , Gooch B.F. , Barker L.K.
Published: January 2009

We analyzed the cost-effectiveness of 3 sealant delivery strategies: Seal all (SA), seal children assessed to be at risk by screening (TARGET), and seal none (SN). We assumed a nine-year analytic horizon, a 3% discount rate, and zero screening costs. Estimates for sealant costs ($27.00) and restoration costs ($73.77), annual caries increment (0.0624 surfaces), sealant failure rate (20% in yr 1 and 3% thereafter), annual amalgam failure rate (4.6%), and sensitivity (0.635) and specificity (0.795) of screening were obtained from published studies. Under baseline assumptions, TARGET dominated (cost less and reduced caries) SA and SN. If annual caries increment exceeded 0.095 surfaces, SA dominated TARGET, and if increment exceeded 0.05 surfaces, TARGET dominated SN. If sealant costs decreased to $6.00 (reported cost for school programs), TARGET dominated SN for caries increments exceeding 0.007 surfaces, and SA dominated TARGET for caries increments exceeding 0.034 surfaces.
Assessment of Enamelysin (MMP-20) Selectivity to Three Peptide Bonds on Amelogenin Sequence
Authors: Wang L. , Moradian-Oldak J.
Published: January 2009

Recent studies have highlighted the potential role of the metalloproteinase enamelysin (MMP-20) in controlling some of the most critical stages during enamel development. This study was aimed to assess the selectivity of enamelysin to the three most abundant cleavage sites on the amelogenin sequence, and to gain insight into the factors that control the pattern of amelogenin processing during enamel mineralization. Three deca-peptides with sequences based on pig amelogenin and including the proteolytic cleavage sites W/L, S/M, and P/A were synthesized as substrates. Statistical analysis revealed no significant differences in the rates of cleavage among the three peptides, indicating comparable selectivity of enamelysin for these peptide bonds. Considering the selective appearance of amelogenin proteolytic products, we suggest that amelogenin folding and assembly are the primary factors in controlling the pattern of its proteolysis during the secretory stage of enamel development.
Odontoblasts Enhance the Maturation of Enamel Crystals by Secreting EMSP1 at the Enamel-Dentin Junction
Authors: Fukae M. , Tanabe T. , Nagano T. , Ando H. , Yamakoshi Y. , Yamada M. , Simmer J.P. , Oida S.
Published: January 2009

The temporal expression patterns and activity distributions of enamelysin and EMSP1, which are the major proteinases in immature enamel, were characterized. Extracellular matrix fractions from developing porcine incisors, individually comprised of predentin, dentin, and four secretory-stage enamel samples, including the highly mineralized enamel (HME) at the enamel-dentin junction (EDJ), were isolated, and their resident proteinases were identified by zymography. Soft-tissue fractions, which included cells from the extension site of enamel formation (ESEF), secretory- and maturation-stage ameloblasts, and odontoblasts, were characterized histologically and by RT-PCR for their expression of enamelysin and EMSP1. A significant finding was that EMSP1, expressed by odontoblasts, concentrates in the HME, but is not detected in predentin or dentin. We conclude that odontoblasts deposit EMSP1 via their cell processes into the deepest enamel layer, which facilitates the hardening of this layer and contributes significantly to the functional properties of the EDJ.
Keratinocyte Growth Factor Receptor is Up-regulated in Cyclosporin A-induced Gingival Hyperplasia
Authors: Das S.J. , Newman H.N. , Olsen I.
Published: January 2009

Keratinocyte growth factor stimulates the growth and activity of epithelial cells via the keratinocyte growth factor receptor. We have recently shown that the growth factor is markedly elevated in cyclosporin A-induced gingival hyperplasia tissue in vivo, but the effects of cyclosporin A on the receptor are not yet known. The present study was therefore carried out to determine whether expression of the keratinocyte growth factor receptor is up-regulated in gingival hyperplasia compared with normal gingiva. Using immunohistochemistry and the reverse-transcribed polymerase chain-reaction, we obtained results which showed that receptor antigen and gene transcript levels were both elevated in gingival hyperplasia tissue. In addition, flow cytometry and the reverse-transcribed polymerase chain-reaction showed that the receptor and mRNA were also higher in gingival epithelial cells following incubation with cyclosporin A in vitro. These findings suggest that the keratinocyte growth factor-receptor pathway of mesenchymal-epithelial interaction could play an important part in the molecular pathogenesis of gingival hyperplasia.
Chondrocyte Proliferation of the Cranial Base Cartilage upon in vivo Mechanical Stresses
Authors: Wang X. , Mao J.J.
Published: January 2009

Whereas the growth of the cranial base cartilage is thought to be regulated solely by genes, epiphyseal growth plates are known to respond to mechanical stresses. This disparity has led to our hypothesis that chondrocyte proliferation is accelerated by mechanical stimuli above natural growth. Two-Newton tensile forces with static and cyclic waveforms were delivered in vivo to the premaxillae of actively growing rabbits for 20 min/day over 12 consecutive days. The average number of BrdU-labeled chondrocytes in the proliferating zone treated with cyclic forces was significantly higher than both static forces of matching peak magnitude and sham controls representing natural chondral growth. Cyclic forces also evoked greater area of the proliferating zone than both static forces and sham controls. Thus, chondrocyte proliferation is enhanced by mechanical stresses in vivo, especially those with oscillatory waveform. Analysis of these data suggests that genetically coded chondral growth is up-regulated by mechanical signals.
Antimicrobial Agents in Saliva—Protection for the Whole Body
Authors: Tenovuo Jorma
Published: January 2009

The author describes his involvement in the discovery of antimicrobial agents in the human mouth.
Cathelicidin Antimicrobial Peptides are Expressed in Salivary Glands and Saliva
Authors: Murakami M. , Ohtake T. , Dorschner R.A. , Gallo R.L.
Published: January 2009

The expression of antimicrobial peptides at epithelial surfaces such as skin, lung, and intestine is thought to provide protection against infection. Cathelicidin antimicrobial peptides are essential for the protection of skin against invasive bacterial infection. To determine if cathelicidins are also present in the oral cavity, we examined the expression of both mRNA and protein in mice and human saliva. The murine cathelicidin (CRAMP) was detected in the adult by reverse-transcription/polymerase chain-reaction (RT-PCR), and in embryonic, newborn, and adult tissues by in situ hybridization and immunohistochemistry. CRAMP mRNA and protein were localized to the salivary glands, specifically in acinar cells of the submandibular gland and palatine minor glands, as well as in lingual epithelium and palatal mucosa. In man, the human cathelicidin LL-37 was detected in human saliva by Western blotting. These results indicate that cathelicidins are present in the salivary system, in some oral epithelia, and in saliva, contributing to broad-spectrum defense of the oral cavity.