bluuebunny/crossref_metadata_2025 huggingface dataset:
United States Immigration Policy and the Industrial Heartland: Laws, Origins, Settlement Patterns and Economic Consequences
Authors: Isserman Andrew M.
Published: October 2006

Immigration laws affect the national composition and size of the immigrant flow. Immigrants from different national origins have markedly different settlement patterns within the US. The regional economic consequences of immigration depend on both the number of immigrants settling within a region and the trade linkages among regions. This article traces the chain from immigration laws to economic consequences for an older industrial region, the Industrial Heartland. Changes in the laws since 1965 have permitted large increases in immigration from several Asian and Latin American countries. These immigrants are less likely to settle in the Industrial Heartland than immigrants from Europe. The National-Regional Impact Evaluation System (NRIES II) an interregional econometric model is used to estimate the economic consequences of the Asian, European and Mexican settlement patterns on the six states of the Heartland. Each case entails adding 100000 immigrants per year nationally for five years. The consequences for the Heartland generally are positive, but they vary within the region and among the settlement patterns.
Evaluating the Links between Housing Change and Economic Change
Authors: Munro Moira
Published: October 2006

Housing policy has been a long-standing and significant element in the regeneration of cities. Housing change is seen as an important element of regeneration in itself, but is further seen to have wider impacts on the economy of urban areas. The dimensions of these impacts are explored in the paper and a framework for evaluating the scale of the spillover effects from housing policy is discussed. Evidence is drawn largely from the Glasgow and Scottish experience. Evidence of the role of housing in facilitating a city response to economic restructuring is argued to be weak, but rational policy development requires that it be better understood.
Changing Competitive Advantage in a Local Economy: The Case of Coventry, 1971-90
Authors: Healey Michael J. , Dunham Philip J.
Published: October 2006

This paper examines the application of Porter's analysis of the competitive advantage of nations to understanding why one British local economy, Coventry, changed from a position of relative competitive disadvantage during the 1970s and early 1980s to one of advantage during the remainder of the 1980s. Each of Porter's four determinants of competitive advantage-supply conditions, demand conditions, firms, and clusters of activities—was found to have had some influence on explaining the change in Coventry's competitive advantage. With the qualification that analyses focus on processes of change and account is taken of the alterations in emphasis needed by changing the scale of analysis from national to local economies, Porter's ideas deserve a wider application and critical examination than they have hitherto received in local and regional economic studies.
Dose-dependent and Isoform-specific Modulation of Ca2+ Channels by RGK GTPases
Authors: Seu Lillian , Pitt Geoffrey S.
Published: October 2006

Although inhibition of voltage-gated calcium channels by RGK GTPases (RGKs) represents an important mode of regulation to control Ca2+ influx in excitable cells, their exact mechanism of inhibition remains controversial. This has prevented an understanding of how RGK regulation can be significant in a physiological context. Here we show that RGKs—Gem, Rem, and Rem2—decreased CaV1.2 Ca2+ current amplitude in a dose-dependent manner. Moreover, Rem2, but not Rem or Gem, produced dose-dependent alterations on gating kinetics, uncovering a new mode by which certain RGKs can precisely modulate Ca2+ currents and affect Ca2+ influx during action potentials. To explore how RGKs influence gating kinetics, we separated the roles mediated by the Ca2+ channel accessory β subunit's interaction with its high affinity binding site in the pore-forming α1C subunit (AID) from its other putative contact sites by utilizing an α1C•β3 concatemer in which the AID was mutated to prevent β subunit interaction. This mutant concatemer generated currents with all the hallmarks of β subunit modulation, demonstrating that AID-β–independent interactions are sufficient for β subunit modulation. Using this construct we found that although inhibition of current amplitude was still partially sensitive to RGKs, Rem2 no longer altered gating kinetics, implicating different determinants for this specific mode of Rem2-mediated regulation. Together, these results offer new insights into the molecular mechanism of RGK-mediated Ca2+ channel current modulation.
Supporting students to develop collaborative learning skills in technology‐based environments
Authors: Nevgi Anne , Virtanen Päivi , Niemi Hannele
Published: October 2006

The paper focuses on the question of how to advance collaboration through the Web and support lifelong learning. First, the theoretical framework and architecture of a new web‐based tool, the ‘IQ Team’, is introduced. IQ Team is an interactive online assessment and support system to learn social skills needed in cooperative work, and belongs in an interactive online assessing and tutoring system, ‘IQ Form’, developed for the Finnish Virtual University. IQ Team has three main elements: (1) interactive self‐evaluation test banks, (2) online tutoring sets and (3) learning diaries. In the creation of IQ Team, the validation process was conducted with two samples (n = 259 andn = 275). The online students’ social skills in different groups were explored, and the feedback data from different user groups were analysed. The online students scored high values for social skills, and no differences were discerned between university, Open University and technical students. The qualitative data (n = 35) were collected in order to get users’ feedback of the tool. The qualitative data consisted of interviews, open‐ended questions and online discussions. The users of IQ Team reflected that the tool benefited them to become aware of their group work skills and developed their collaborative learning skills. IQ Team provides a powerful tool for online instruction and communication in higher education and in the Open University to promote joint‐regulated learning.
The Role of the Position Effect in Theory and Simulation
Authors: KÜHBERGER ANTON , KOGLER CHRISTOPH , HUG ANGELIKA , MÖSL EVELYNE
Published: October 2006

Abstract:  We contribute to the empirical debate on whether we understand and predict mental states by using simulation (simulation theory) or by relying on a folk psychological theory (theory theory). To decide between these two fundamental positions, it has been argued that failure to predict other people’s choices would be challenging evidence against the simulation view. We test the specific claim that people prefer the rightmost position in choosing among equally valued objects, and whether or not this position bias can be correctly predicted. A series of experiments shows that the bias appears only in a specific spatial arrangement and that it can be correctly predicted given adequate imaginative input. In concert with other recent findings on the correct prediction of choices these findings do actually strengthen, rather than challenge, the simulation account on the prediction of mental states.
Bypassing of a polygenicMicrocyclus uleiresistance in rubber tree, analyzed by QTL detection
Authors: Le Guen V. , Garcia D. , Mattos C. R. R. , Doaré F. , Lespinasse D. , Seguin M.
Published: October 2006

Genetic resistance components of theHevea brasiliensis × H. benthamianaRO 38 cultivar toMicrocyclus uleidisease were investigated by inoculating isolates which succeeded in partially or completely infecting genotypes of a mapping population.

Progeny of a cross between RO 38 and a susceptible cultivar was inoculated under controlled conditions with three isolates and scored for two resistance traits. Interval mapping and a nonparametric test were used to detect resistance quantitative trait loci (QTLs).

Eight significant QTLs were detected, all of them inherited from the interspecific parent. Among these QTLs, only one contributed to the partial resistance against a highly pathogenic isolate, and no QTL was detected for resistance against the most pathogenic isolate. As an unexpected result, a single isolate can thus completely bypass this polygenic resistance.

This complex situation, where no clear relationship can be established between number of resistance factors and qualitative vs quantitative or partial vs complete resistance, is discussed and suggestions as to the detection of new and sustainable resistance sources are proposed.
Soil physical fertility, soil structure and rooting conditions after ploughing organically managed grass/clover swards
Authors: Ball B. C. , Watson C. A. , Baddeley J. A.
Published: October 2006

Effective management of soil structure and organic matter are essential in organic cropping to ensure good rooting conditions and to optimize the production of mineralized N and thus minimize greenhouse gas emissions. We investigated how mid‐winter or early spring ploughing and three grazing duration treatments prior to ploughing influenced soil structure, soil organic matter and plant root growth under the first spring barley crop after a grass–clover ley. The experiment was carried out over two seasons. We also studied the soil under first‐year oats in a long‐term rotations experiment where 2 or 3 years of arable crops followed 3 or 4 years of grass. Pore size distribution and pore continuity, bulk density, particulate (light fraction) organic matter, readily oxidizable organic matter (ROM), aggregate size distribution and root length densities were measured. Macroporosity appeared to be the best indicator of soil physical fertility; it was sensitive to changes in soil structure arising from compaction and root growth. This, along with visual examination, revealed the loosening resulting from ploughing. The generally favourable macroporosity amongst small, stable aggregates reduced the likelihood of development of anaerobism. Macroporosity and aggregate size can be estimated from visual examination of the soil, a method that offers the advantage of being quick and of sampling a large volume. The content of ROM was high 6.1–6.4 g 100 g−1 whole soil. However, particulates formed only a small fraction (6–9%) of the ROM. Despite the favourable ROM and structure, the soil was susceptible to compaction damage during seedbed preparation in wet soil after ploughing which reduced grain yield in some plots. Grazing by sheep before ploughing and date of ploughing had minor effects on soil quality. Grazing for 2 months prior to ploughing increased root length density in the upper topsoil in the following arable crop, possibly because of the higher quality of the animal and grass–clover residues. Conservation of soil quality was related more to secondary tillage and sowing operations after ploughing than to duration and timing of grazing.
National territory in European space: Reconfiguring the island of Ireland
Authors: HAYWARD KATY
Published: October 2006

Abstract.  The meaning and significance of borders in nation‐statehood and European integration are integrally linked in a process of change. Uncovering such connections in a case study notable for its recent transformation, this article explores the way in which the narratives and models of European integration have been used in the discourse of Irish official nationalism. Its central thesis is that participation in the space of European Union has facilitated the conceptualization of a common Irish space in which borders (specifically the Irish border) are not conceived as barriers to be overcome, but rather as bridges to the fulfilment of interests. Thus, the Irish governmental elite have used the language of European integration to reconfigure traditional ideals of latent anti‐partitionism for a context of peaceful settlement.
The Changing Focus of Child Maltreatment Research and Practice Within Psychology
Authors: Chaffin Mark
Published: October 2006

Professions functionally define a field by the types of behaviors or circumstances to which they direct their attention and efforts. For psychology and mental health professionals concerned with child maltreatment, child sexual abuse has been the dominant interest over the past two decades and has been virtually synonymous with child maltreatment within psychology. This is discrepant from the broader scope of child maltreatment, as seen both in child welfare populations and in the general population. In child welfare, sexual abuse is an important but nonetheless relatively less frequent issue. Child neglect and physical abuse dominate child welfare caseloads, and historically always have. The disconnect between the interests of mental health professionals and child welfare appears to be waning, both in terms of dialogue within psychology and apportioning of research resources. This article examines what this emerging change may mean for practice and research in terms of the changing nature of populations involved, different types and locations of services, different roles and new multidisciplinary alliances.
Children's Eyewitness Memory: A Modern History and Contemporary Commentary
Authors: Goodman Gail S.
Published: October 2006

This article provides a modern historical overview of child eyewitness research, as well as an evaluative commentary on the field, with special emphasis on children's eyewitness memory and suggestibility in child sexual abuse cases. Four historical periods are reviewed: the 1970s, 1980s, 1990s, and 2000s (to date). Examples of legal cases that inform scientific research are described, discussion of relevant laws is presented, and a review of selected studies is offered. It is concluded that although we have learned a great deal about children's eyewitness memory and suggestibility over the last few decades, simple answers are evasive and much more research is needed.
The Marius Implant Bridge: Surgical and Prosthetic Rehabilitation for the Completely Edentulous Upper Jaw with Moderate to Severe Resorption: A 5‐Year Retrospective Clinical Study
Authors: Fortin Yvan , Sullivan Richard M. , Rangert Bo R.
Published: October 2006

Background: Patients seeking replacement of their upper denture with an implant‐supported restoration are most interested in a fixed restoration. Accompanying the loss of supporting alveolar structure due to resorption is the necessity for lip support, often provided by a denture flange. Attempts to provide a fixed restoration can result in compromises to oral hygiene based on designs with ridge laps. An alternative has been an overdenture prosthesis, which provides lip support but has extensions on to the palate and considerations of patient acceptance. The Marius bridge was developed as a fixed bridge alternative offering lip support that is removable by the patient for hygiene purposes, with no palatal extension beyond normal crown‐alveolar contours.

Purpose: Implant‐supported restorative treatment of completely edentulous upper jaws, as an alternative to a complete denture, is frequently an elective preference, and it requires significant patient acceptance beyond the functional improvement of chewing. Patients with moderate to severe bone resorption and thin ridges present additional challenges for adequate bone volume and soft‐tissue contours. The purpose of this investigation was to develop a surgical and prosthetic implant treatment protocol for completely edentulous maxillae in which optimal lip support and phonetics is achieved in combination with substantial implant anchorage without bone grafting.

Materials and Methods: The Marius bridge is a complete‐arch, double‐structure prosthesis for maxillae that is removable by the patient for oral hygiene. The first 45 consecutive patients treated by one person (YF) in one center with this concept are reported, with 245 implants followed for up to 5 years after prostheses connection.

Results: The cumulative fixture survival rate for this 5‐year retrospective clinical study was 97%. Five fixtures failed before loading, in five different patients, and two fixtures in the same patient failed at the 3‐year follow‐up visit. None of the bridges failed, giving a prostheses survival rate of 100%. The complications were few and mainly prosthetic: nine incidences of attachment component complications, one mesobar fracture, and three reports of gingivitis. All complications were solved or repaired immediately, with minimal or no interruption of prostheses use.

Conclusions: Satisfactory medium‐term results of survival and patient satisfaction show that the Marius bridge can be recommended for implant dentistry. The technique may reduce the need for grafting, because it allows for longer implants to be placed with improved bone anchorage and prostheses support.
Immediate Loading of Brånemark Implants: a 24‐Month Follow‐Up of a Comparative Prospective Pilot Study between Mandibular Overdentures Supported by Conical® Transmucosal and Standard MK II Implants
Authors: Gatti Claudio , Chiapasco Matteo
Published: October 2006

Background: The purpose of this prospective study is to compare the long‐term outcome of immediately loaded implantretained mandibular overdentures supported by four screw‐type one‐piece transmucosal implants with that of four screw‐type two‐piece implants inserted in the interforaminal area of the mandible and rigidly connected by a U‐shaped curved

Materials and Methods: A prospective pilot study was conducted with 10 patients receiving an implant‐supported overdenture in the mandible. The patients were randomly assigned to two groups. In the control group (five patients), four standard Brånemark implants (MK II; Nobel Biocare AB, Gothenburg, Sweden), 3.75 mm large and at least 10 mm long, were sited anterior to the mental foramina, and four standard abutments (Nobel Biocare AB) for bar construction were immediately screwed to the implants. In the test group (five patients), four conical transmucosal implants (Nobel Biocare AB), 3.75 mm large and at least 9 mm long in the threaded part, were sited anterior to the mental foramina. Immediately after implant placement, a U‐shaped gold or titanium bar was fabricated and implants were immediately loaded (within 24 h) in both groups with an implant‐retained overdenture. The patients were followed up for a minimum of 24 months. Implants were evaluated at the time of immediate loading and at 12 and 24 months after prosthetic loading, with the following parameters: modified plaque index (MPI), modified bleeding index (MBI), and probing depth (PD). Periimplant bone resorption was evaluated on panoramic radiographs taken 12 and 24 months after the beginning of prosthetic loading.

Results: No significant differences were found between the two groups with regard to MPI, MBI, PD, and periimplant bone resorption at 12 and 24 months. The cumulative success rate of implants according to the criteria proposed by Albrektsson and colleagues was 100% in both groups after 2 years of functional loading.

Conclusions: Results from this study demonstrated that the success rate for immediately loaded mandibular implants is similar to that obtained in cases of delayed loading and that there are no significant differences between results with two‐piece implants and one‐piece transmucosal implants.
Histology of Retrieved Immediately and Early Loaded Oxidized Implants: Light Microscopic Observations after 5 to 9 Months of Loading in the Posterior Mandible
Authors: Rocci Antonio , Martignoni Massimiliano , Burgos Patricia Miranda , Gottlow Jan , Sennerby Lars
Published: October 2006

Background:

An increased number of publications report that one‐stage surgery and immediate/early loading of dental implants may be a feasible approach for prosthetic reconstruction of the edentate patient. However, little is known about the histologic response to implants subjected to immediate/early loading in patients.

Purpose:

The aim of the present study was to histologically evaluate oxidized titanium implants subjected to loading immediately following surgery or after 2 months of healing and removed after 5 to 9 months loading.

Materials and Methods:

Five patients participated in the study; each had consulted for implant treatment in the posterior mandible and subsequently volunteered to have extra implants inserted for the purpose of histologic research. Nine oxidized titanium implants (Brånemark System® TiUnite™, Nobel Biocare AB, Gothenburg, Sweden) were retrieved after 5 to 9 months in function. Two implants had been loaded the same day, whereas seven implants were loaded after 2 months of healing. Resonance frequency analysis was performed at retrieval on seven implants. Ground sections were prepared for histology and analyzed using light microscopic morphometry.

Results:

Seven and 8.5 mm implants were placed, predominantly in quality 3 and 4 bone. Four implants were straight (Mk III), and five were tapered (Mk IV). All implants were clinically stable at retrieval and showed ISQ values of 65 to 79 with a mean of 71.4 ± 4.4. Eight of the implants were able to be used for histology. A gross histologic examination showed an undisturbed healing of soft and bone tissues with no apparent differences between response to immediately and early loaded implants. Lamellar bone surrounded the implants, and remodeling was evident and more marked near the implant surface. A condensation of bone toward the implant surface was seen; this resulted in a lamina dura‐like structure in trabecular bone. Thin rims of newly formed bone were often seen following the contour of the implant surface. The morphometric measurements showed a mean bone‐to‐implant contact value of 84.2 ± 10.5% and a mean bone area value of 79.1 ± 6.8%. The two immediately loaded implants showed bone‐to‐implant contact and bone area values of 92.9 ± 0.1% and 84.9 ± 0.9%, respectively. The corresponding values for the six early loaded implants were 81.4 ± 10.6% and 77.1 ± 6.8%, respectively.

Conclusions:

The present study demonstrated that oxidized implants subjected to immediate or early loading do integrate with soft and bone tissues in the posterior mandible.
One‐Year Prospective Three‐Center Study Comparing the Outcome of a “Soft Bone Implant” (Prototype Mk IV) and the Standard Brånemark Implant
Authors: Friberg Bertil , Jisander Sven , Widmark Göran , Lundgren AnnaKarin , Ivanoff Carl‐Johan , Sennerby Lars , Thorén Christina
Published: October 2006

Background: Oral implant treatment ad modum Brånemark has been used for decades in the rehabilitation of edentate and partially dentate patients. Posterior jaw regions frequently exhibit bone of poor texture, and it is often difficult to obtain primary stability. Thus, it may prove beneficial to deviate from the original protocol and to use implants with a modified design, for example, with a slightly tapered geometry.

Purpose: The purpose of the investigation was to compare the early behavior of a modified (prototype Mk IV, Branemark System, Nobel Biocare AB, Gothenburg, Sweden; test) implant with that of the standard Brånemark implant (control) in regions of mainly type 4 bone.

Materials and Methods: Three Swedish centers participated, and a total of 44 patients were treated with oral implants for 39 maxillas and 5 mandibles. The study focused on the most distal right and left implant sites (88 implants), which were randomized to receive either a test or a control implant. Various parameters were recorded, such as registered insertion torque (OsseoCare, Nobel Biocare AB), wobbling during insertion, primary and secondary stability (as measured with resonance frequency), and marginal bone loss. The implants were followed up for 1 year.

Results.: The test implant more frequently required a higher insertion torque and showed a significantly higher primary stability than the control implant. This difference in stability leveled out over time, and test and control implants exhibited similar secondary stability at abutment operation and at the 1‐year visit. Wobbling during insertion was rarely recorded for either of the implant designs. The 1‐year cumulative success rate was 93.1% for test implants and 88.4% for control implants.

Conclusions: The modified implant design resulted in an increased primary stability, which may be important when placing implants in jaw regions of type 4 bone. However, independent of the achieved primary stability, successful implants tended to approach similar secondary stability in the two designs tested.
Immediate Replacement of Single Upper Posterior Teeth: A Report of Cases
Authors: Vergara Jaime A. , Caffesse Raul G.
Published: October 2006

Background: The immediate replacement of upper molar teeth with implants poses a significant challenge to the clinician because of its sinus involvement.

Purpose: The purpose of this article is to report a protocol in which single molar teeth are replaced immediately with implants, minimizing the need for other surgical procedures.

Materials and Methods: This protocol has been employed in eight cases. Briefly, the teeth are extracted atraumatically, the sockets evaluated, an osteotomy performed following the direction of the socket, and a wide diameter implant placed using the socket walls and sinus floor to anchor it. A grafting material is placed when the space between implant and socket wall is considerably large. Three cases are reviewed here, and all eight are summarized.

Results: All cases have excellent soft and hard tissue healing after 6 months. Furthermore, the overall time needed to restore the cases has been considerably reduced and the need for sinus management eliminated.

Conclusion: The cases presented support the use of the described protocol in the placement of implants in maxillary molar areas without any other sinus procedures.
Surgical Intervention in Enchondral and Membranous Bone: Intraindividual Comparisons in the Rabbit
Authors: Slotte Christer , Lundgren Dan , Sennerby Lars , Karin Lundgren Anna
Published: October 2006

Background: The long bones, which are of enchondral origin, are often used in histologic evaluations of dental implants that clinically will be placed in bones of membranous origin.

Purpose: The aim of this investigation was to study the effect of surgical trauma by multiple drill perforations on both enchondral and membranous bone—the tibial and maxillary bone architecture—8 weeks after surgery.

Materials and Methods: In eight rabbits the medial metaphyses of both tibiae and the edentulous ridges of both sides in the maxilla were surgically exposed. On the test sides, 25 to 30 holes were drilled through the cortical plate and 5 mm into the medullary space. The contralateral sides underwent no treatment and served as controls. Eight weeks later the animals were killed to obtain transverse ground sections for histomorphometry. A paired analysis of the bone densities of the tibiae and the jaw specimens was made.

Results: In general the morphologic appearances of the test and control tibiae were similar. In the control group the anatomy of the medullary space appeared normal, with few bone trabeculae and with abundant marrow tissue. In the test group, areas of resorption were evident on the cortical bone plate that had been perforated 8 weeks previously; also evident were ingrowths of marrow tissue and bone formation. In a few specimens some newly formed bone trabeculae were found in the medullary space, both contiguous to the perforated cortical bone plate and as small islets in the marrow tissue. The mean test and control site values for each parameter were similar, and no statistically significant differences were found. In the maxilla, the bone architecture had altered substantially by way of an increase in the proportion of trabecular bone and a decrease in the proportion of cortical bone. Drilling appeared to have little effect on tibial bone density, which did not significantly differ between test and control sites. Maxillary bone density, however, was significantly greater at the test sites than at the control sites. Comparisons of bone density between tibia and jaw specimens revealed no significant differences either between test sides or between control sides. Thus, the same magnitude of surgical trauma that altered the bone architecture and density of the rabbit maxilla was not found to have altered those of the tibia in the same animal 8 weeks after surgery. The reasons for the differences are discussed in this article.

Conclusions: As observed 8 weeks post surgery, multiple drill perforations were not found to cause significant alterations in the metaphysis of the tibia whereas a considerable change in bone architecture and an increase in bone density were found in the maxilla. Whether this depends on different embryologic origins or reflects morphologic and functional differences in the mature bone demands further study.
A Comparative Study of Computed Tomography and Magnetic Resonance Imaging for the Detection of Mandibular Canals and Cross‐Sectional Areas in Diagnosis prior to Dental Implant Treatment
Authors: Imamura Hideyuki , Sato Hironobu , Matsuura Takashi , Ishikawa Masatsugu , Zeze Ryousuke
Published: October 2006

Background:

Computed tomography (CT) is effective in the diagnosis of dental implants. However, it has the disadvantage of exposing patients to high doses of x‐rays, and the mandibular canals cannot be detected by CT in some clinical cases.

Purpose:

The purpose of this study was to examine the detectability of the anatomic morphology of the molar region in the lower jaw (where implantation is common) by CT and magnetic resonance imaging (MRI), to compare the data, and to determine the usefulness of MRI in diagnosis prior to dental implant treatments.

Materials and Methods:

Eleven female subjects (average age, 59 years) who had partially edentulous mandibles (total of 19 sites) were included in the study. CT and MRI were performed with the same subjects, and the degrees of identification of the mandibular canal in the first and second molar regions were compared. Dimensional accuracy in the second molar region was also compared.

Results:

With CT, the canals of the first molar regions were not identified in 11 of 19 sites; however, MRI identified the canals in all 19 sites. Using the kappa index, we found that the inter‐ and intraobserver identification reliabilities (0.84 and 0.87, respectively) were excellent, especially for MRI. Dimensional positioning of the canal in the second molar region was almost the same with MRI as with CT.

Conclusions:

MRI is an alternative method in diagnosis prior to dental implant treatment in the mandibular molar region.
Clinical Performance of a Method for the Fabrication of Implant‐Supported Precisely Fitting Titanium Frameworks: A Retrospective 5‐ to 8‐Year Clinical Follow‐Up Study
Authors: Hedkvist Lars , Mattsson Torsten , Helldén Leif B.
Published: October 2006

Background: The CrescoTi Precision® (CTiP) method (CrescoTi Systems, Lausanne, Switzerland) has been introduced as an alternative method for the fabrication of precisely fitting titanium frameworks. The method is supposed to be used with all major implant systems, without the need for abutments.

Purpose: The objectives of this clinical and radiographic retrospective follow‐up study were to report the clinical performances of “CTiP‐fabricated” frameworks that are screw retained directly to Brånemark implants as opposed to Brånemark implant/abutment assemblies (Nobel Biocare AB, Gothenburg, Sweden) and to compare the clinical outcomes of these two modalities.

Materials and Methods: Thirty‐six patients were provided with 46 fixed prostheses supported by 207 Brånemark regular‐platform implants. Twenty‐seven prostheses were placed on implant/abutment assemblies, and 19 were placed directly at “implant level.” The prostheses had been in function for 5 to 8 years at the time of the final examinations.

Results: Three patients did not attend the final examination. All 43 prostheses in the 33 examined patients were still in function. No major mechanical framework complications were observed during the observation period. One implant was lost after loading. There was no difference in bone loss around the abutment‐free implants when compared with the implants provided with abutments.

Conclusions: This long‐term clinical test demonstrated that the CTiP technology constitutes a reliable prosthetic treatment concept in combination with Brånemark implants. The results also revealed that the frameworks could be connected directly to the implants without any negative consequences.
Scanning Electron Microscopy Study of Dental Enamel Surface Exposed to 35% Hydrogen Peroxide: Alone, With Saliva, and With 10% Carbamide Peroxide
Authors: SPALDING MARIANNE , TAVEIRA LUÍS ANTÔNIO DE ASSIS , DE ASSIS GERSON FRANCISCO
Published: October 2006

Several vital bleaching systems have been introduced in response to the demand in esthetic dentistry. The active agents are commonly hydrogen peroxide or carbamide peroxide used in at‐home or in‐office techniques. Although generally positive results have been reported concerning the whitening ability of these agents, concerns still remain as to their effects on dental tissues. The purpose of this investigation was to evaluate the effect of these bleaching agents on the enamel surface morphology. Twelve extracted teeth were used according to three experimental protocols. In experimental protocol 1, specimens were treated with 35% hydrogen peroxide. In experimental protocol 2, after treatment with 35% hydrogen peroxide the specimens were immersed in natural saliva for 1 week. In experimental protocol 3, 35% hydrogen peroxide was applied once and 10% carbamide peroxide was applied for 1 week (12 h of 10% carbamide peroxide alternating with 12 h saliva). Scanning electron microscopy evaluation revealed that regional variation in tooth morphology surface sometimes exceeded the effects of the peroxide used according to experimental protocols. Thirty‐five percent hydrogen peroxide had a tendency to promote an increase in density of pits. Precipitates were observed on specimen surfaces immersed in natural saliva according to protocol 2. A smooth and shiny surface was observed in specimens treated according to protocol 3. The potential relationship between surface alterations and differences in enamel permeability is currently under investigation.

CLINICAL SIGNIFICANCE

The differences in various articles written on the subject cannot be reconciled because of the lack of standardization of baseline data regarding factors such as location on the tooth, type of tooth, eruption or noneruption, and age in the oral cavity. This article demonstrates that, despite changes observed in the enamel surface after bleaching, normal variation in tooth morphology may exceed the effects of 35% hydrogen peroxide and 10% carbamide peroxide on the teeth. Hence, considering the morphologic features of the tooth surface, bleaching, as described in this study, can be considered safe for enamel.
Perioesthetic Approach to the Diagnosis and Treatment of Carious and Noncarious Cervical Lesions: Part I
Authors: TERRY DOUGLAS A. , McGUIRE MICHAEL K. , McLAREN EDWARD , FULTON RUDOLPH , SWIFT EDWARD J.
Published: October 2006

Several factors can contribute to the development of noncarious cervical lesions. Therefore, these lesions can be described and classified according to their primary etiology. Traditionally, most dentists have treated noncarious cervical lesions only with restorative methods, for example, composite resin restorations. However, in many cases, a periodontal or a combined restorative/periodontal approach provides a better esthetic and functional result. In part I of this two‐part report, we provide a review of noncarious cervical lesions and a series of clinical case reports showing surgical techniques used and the importance of the periodontal aspect of lesion management.

CLINICAL SIGNIFICANCE

For best esthetic results, the periodontal aspect of noncarious cervical lesions must be considered in treatment planning.
Esthetic Soft Tissue Ridge Augmentation Using an Acellular Dermal Connective Tissue Allograft
Authors: MAHN DOUGLAS H.
Published: October 2006

Residual ridge defects present significant limitations to the esthetic restoration of edentulous tooth sites. Augmentation techniques can aid in the re‐establishment of natural ridge contours. This article describes a technique in which an acellular dermal connective tissue allograft is used to augment a buccolingual residual ridge defect. A single vertical incision enables the allograft to be placed laterally into a buccal pouch. Augmentation of this edentulous site permitted a three‐unit bridge to be placed with a highly esthetic pontic.

CLINICAL SIGNIFICANCE

This article presents a simplified method of esthetic ridge augmentation that reduces patient discomfort.
Does the Wear Resistance of Packable Composite Equal that of Dental Amalgam?
Authors: SUZUKI SHIRO
Published: October 2006

Background:

There is little evidence that packable composites are sufficiently wear resistant to be used as an alternative to amalgam.

Purpose::

The purpose of this study was to evaluate wear rates of packable composites compared with hybrid resin composites and amalgams by an in vitro wear test.

Materials and Methods:

The following composites were used: three packable composites (SureFil, Dentsply/Caulk, Milford, DE, USA; Alert, Pentron Clinical Technologies, Wallingford, CT, USA; and Solitaire, Heraeus Kulzer, Wehrheim, Germany), two hybrid resin composites (TPH Spectrum, Dentsply/Caulk; and Pyramid enamel, Bisco Inc., Schaumburg, IL, USA), and two amalgams (Tytin, Kerr Manufacturing Co., Romulus, MI, USA; and Dispersalloy, Dentsply/ Caulk). Cylindrical Class I cavities prepared on occlusally flattened, extracted human molars were restored with respective materials according to the manufacturers’instructions. Generalized, localized, and antagonistic enamel wear tests were carried out by a University of Alabama at Birmingham (UAB) wear simulator according to previously reported methods. Seven specimens were tested for each group, and the wear depths were measured on profilometric tracings. The data for each wear mode were independently analyzed by one‐way analysis of variance and Fisher's exact test (p .05).

Results:

The generalized wear values for SureFil (7.0 ± 3.5 μm), Alert (8.6 ± 1.8 μm), and Pyramid (3.9 ± 0.5 μm) were not statistically different from those of amalgam materials (Tytin 5.8 ± 0.7 μm, Dispersalloy 6.0 ± 0.9 μm) but were different from those of Solitaire (23.9 ± 2.6 μm) and TPH (30.6 ±5.5μm). The localized wear values for SureFil (19.8 ± 14.2 μm) and Alert (28.0 ± 1.6 μm) were significantly smaller than for all other materials. For antagonistic enamel wear, Solitaire exhibited a minimal value (3.4 ± 0.9 μm), whereas values of SureFil (12.6 ±5.6μm) and Alert (12.0 ±6.6μm) were not statistically different from those of TPH (11.0 ± 4.0 μm) and amalgams (Tytin 14.5 ± 4.3 μm, Dispersalloy 7.8 ± 3.3 μm).

Conclusions: It can be concluded that SureFil and Alert packable composites possess similar wear resistance and abrasiveness to amalgam on the basis of the limitations of this study, which simulated 3 years of clinical wear.
Encephalopathy after cyclophosphamide with response to methylene blue
Authors: GEDYE Craig A , STEWART Josephine , CHER Lawrence M
Published: October 2006

We present two cases of encephalopathy occurring after chemotherapy containing cyclophosphamide. Patient 1 was receiving vincristine, cisplatin and cyclophosphamide for recurrent medulloblastoma, whilst patient 2 received cyclophosphamide‐containing chemotherapy as adjuvant treatment for early breast cancer. After cumulative doses of 2.8 and 6 g/m2of cyclophosphamide both patients developed a gradual onset of fluctuating attention, slowed mentation and decreased consciousness. Extensive investigations excluded other causes of this altered conscious state. Given the similarity of presentation to ifosfamide encephalopathy, methylene blue (50 mg i.v.) was administered. Patient 1 experienced an immediate improvement that was not sustained, with a subsequent deterioration over several weeks and became unresponsive before death. Patient 2 experienced a dramatic improvement within 3 h and received a second dose of methylene blue with further improvement. To our knowledge, cyclophosphamide has not previously been implicated as a cause of encephalopathy. A review of the literature is presented. We hypothesize that cyclophosphamide may rarely cause encephalopathy and may also contribute to the cognitive dysfunction reported in association with chemotherapy for breast cancer and non‐Hodgkin’s lymphoma.
Physician Participation in Executions: Care Giver or Executioner?
Authors: Clark Peter A.
Published: October 2006

To circumvent objections that the death penalty was “cruel and unusual punishment” and therefore a violation of the Eighth Amendment to the Constitution, advocates proposed lethal injection and the involvement of physicians to overcome the negative perceptions associated with the death penalty, and to increase public acceptability of the practice. Initiated in 1982, lethal injection is now the primary method of execution in 37 of the 38 states with the death penalty. “To be exact, this method has been used to kill 788 of the 956 men and women who have been executed in the United States since 1976, when the death penalty was reinstated by the Supreme Court.” More recently, of the 191 executions performed in the United States since 2001, 189 have been by lethal injection.

This “medicalization” of the death penalty has ignited a debate, by those within the medical profession and by others outside it, about the appropriateness of physicians participating in executions.
The Ethical Health Lawyer: Ethical Lawyering in the Gray Areas: Health Care Fraud and Abuse
Authors: Krause Joan H.
Published: October 2006

Few areas of health law practice present as many quandaries for the ethical health lawyer as health care fraud and abuse. The activities addressed by the anti-fraud laws – such as payment for referrals and submission of false claims – not only have a direct impact on the financial viability of the federal health care programs, but go to the heart of the ethical behaviors expected of those who transact business with the government. The severe consequences of violating these proscriptions include significant monetary penalties, ineligibility to participate in the federal health care programs, and even imprisonment. It is no wonder, then, that compliance with the fraud and abuse laws is a key consideration in any health care venture. At the same time, ethical considerations make this area of health law particularly vexing for counsel, raising numerous challenges that include how to balance the strategic goals of current clients against the interests of future clients and whether to advise clients to self-report potential violations even when illegal intent may not easily be shown.
Sinning against nature: the theory of background conditions
Authors: Blackford R
Published: October 2006

Debates about the moral and political acceptability of particular sexual practices and new technologies often include appeals to a supposed imperative to follow nature. If nature is understood as the totality of all phenomena or as those things that are not artificial, there is little prospect of developing a successful argument to impugn interference with it or sinning against it. At the same time, there are serious difficulties with approaches that seek to identify "proper" human functioning. An alternative approach is to understand interference with nature as acting in a manner that threatens basic background conditions to human choice. Arguably, the theory of background conditions helps explain much of the hostility to practices and technologies that allegedly sin against nature. The theory does not, however, entail that appeals to nature are relevant or rational. Such appeals should be subjected to sceptical scrutiny. Indeed, the theory suggests that arguments against practices and technologies that can be seen as contrary to nature sometimes exercise a psychological attraction that is disproportional to their actual cogency.
Importance of the advance directive and the beginning of the dying process from the point of view of German doctors and judges dealing with guardianship matters: results of an empirical survey
Authors: van Oorschot B , Simon A
Published: October 2006

Objectives:To analyse and compare the surveys on German doctors and judges on end of life decision making regarding their attitudes on the advance directive and on the dying process.

Design:The respondents were to indicate their agreement or disagreement to eight statements on the advance directive and to specify their personal view on the beginning of the dying process.

Participants:727 doctors (anaesthetists or intensive-care physicians, internal specialists and general practitioners) in three federal states and 469 judges dealing with guardianship matters all over Germany.

Main measurements:Comparisons of means, analyses of variance, pivot tables (χ2test) and factor analyses (varimax with Kaiser normalisation).

Results:Three attitude groups on advance directive were disclosed by the analysis: the decision model, which emphasises the binding character of a situational advance directive; the deliberation model, which puts more emphasis on the communicative aspect; and the delegation model, which regards the advance directive as a legal instrument. The answers regarding the beginning of the dying process were broadly distributed, but no marked difference was observed between the responding professions. The dying process was assumed by most participants to begin with a life expectancy of only a few days.

Conclusions:A high degree of valuation for advance directive was seen in both German doctors and judges; most agreed to the binding character of the situational directive. Regarding the different individual concepts of the dying process, a cross-professional discourse on the contents of this term seems to be overdue.
Why tell asymptomatic children of the risk of an adult-onset disease in the family but not test them for it?
Authors: Malpas P J
Published: October 2006

This paper first considers why it is important to give children genetic information about hereditary conditions in the family, which will go on to affect their lives in a salient way. If it is important to inform children that they are at risk for an adult-onset disease that exists in the family, why should they not also grow up knowing whether they actually carry the genetic mutation? Central to this discussion is the importance of the process of disclosure and the environment in which genetic information is divulged. It is concluded that the reasons given for defending disclosure of genetic conditions in the family to children are also important reasons to cautiously defend predictive genetic testing of children for adult-onset diseases.