Bone dimensions in the posterior mandible: a retrospective radiographic study using cone beam computed tomography. Part 1--analysis of dentate sites

This retrospective radiographic study analyzed the dimensions of the alveolar bone in the posterior dentate mandible based on cone beam computed tomography (CBCT) images. A total of 56 CBCT images met the inclusion criteria, resulting in a sample size of 122 cross sections showing posterior mandibular teeth (premolars and molars). The thickness of the buccal and lingual bone walls was measured at two locations: 4 mm apical to the cementoenamel junction (measurement point 1, MP1) and at the middle of the root (measurement point 2, MP2). Further, alveolar bone width was assessed at the level of the most coronal buccal bone detectable (alveolar bone width 1, BW1) and at the superior border of the mandibular canal (alveolar bone width 2, BW2). The vertical distance between the two as well as the presence of a lingual undercut were also analyzed. There was a steady increase in buccal bone wall thickness from the first premolar to the second molar at both MP1 and MP2. BW1 at the level of the premolars was significantly thinner than that for molars. Alveolar bone height was constant for all teeth examined. For the selection of an appropriate postextraction treatment approach, analysis of the alveolar bone dimensions at the tooth to be extracted by means of CBCT can offer valuable information concerning bone volume and morphology at the future implant site.

Immediate restoration of nonsubmerged titanium implants with a sandblasted and acid-etched surface: five-year results of a prospective case series study using clinical and radiographic data

The aim of this study was to evaluate the survival and success rates of immediately restored implants with sandblasted, large-grit, acid-etched (SLA) surfaces over a period of 5 years. Twenty patients (mean age, 47.3 years) received a total of 21 SLA wide-neck implants in healed mandibular first molar sites after initial periodontal treatment. To be included in the study, the implants had to demonstrate primary stability with an insertion torque value of 35 Ncm. A provisional restoration was fabricated chairside and placed on the day of surgery. Definitive cemented restorations were inserted 8 weeks after surgery. Community Periodontal Index of Treatment Needs (CPITN) indices and the radiographic distance between the implant shoulder and the first visible bone-implant contact (DIB) were measured and compared over the study period. The initial mean CPITN was 3.24, and decreased over the study period to 1.43. At the postoperative radiographic examination, the mean DIB was 1.41 mm for the 21 implants, indicating that part of the machined neck of the implants was placed slightly below the osseous crest. The mean DIB value increased to 1.99 mm at the 5-year examination. This increase proved to be statistically significant (P < .0001). Between the baseline and 5-year examinations, the mean bone crest level loss was 0.58 mm. Success and survival rates of the 21 implants after 5 years of function were 100%. This 5-year study confirms that immediate restoration of mandibular molar wide-neck implants with good primary stability, as noted by insertion torque values of at least 35 Ncm, is a safe and predictable procedure.

The Assertion of Identity: Storytelling and Testimony in the Works of Edwidge Danticat

Haitian-American author Edwidge Danticat evokes the Haitian tradition of storytelling in many of her novels and short story collections. A tradition formulated by vodou religion and the amalgamation of African cultures, storytelling acts to entertain, educate and enlighten the people of Haiti. Additionally, her novels are often written in the context of traumatic events in Haitian history. While Danticat's works have been studied with focus on their depiction of storytelling and of trauma, little has been done on the restorative power that storytelling provides. In this thesis, I seek to examine the potential for Danticat's characters and works to create narratives that build community, present testimony, and aid traumatized individuals in recovery.

Dental erosion in children

Erosive tooth wear in children is a common condition. The overlapping of erosion with mechanical forces like attrition or abrasion is probably in deciduous teeth more pronounced than in permanent teeth. Early erosive damage to the permanent teeth may compromise the dentition for the entire lifetime and require extensive restorative procedures. Therefore, early diagnosis of the condition and adequate preventive measures are of importance. Knowledge of the etiological factors for erosive tooth wear is a prerequisite for such measures. In children and adolescents (like in adults) extrinsic and intrinsic factors or a combination of them are possible reasons for the condition. Such factors are frequent and extensive consumption of erosive foodstuffs and drinks, the intake of medicaments (asthma), gastro-esophageal reflux (a case history is discussed) or vomiting. But also behavioral factors like unusual eating and drinking habits, the consumption of designer drugs and socio-economic aspects are of importance.

Experimental intracerebral hematoma in the rat

Current models of intracerebral hematoma are difficult to use for neurotransplantation studies because of high mortality and important variations of morphology, size and location of blood deposits. We propose a modification of the autologous blood infusion technique in rats to reduce these limitations.

Clinical evaluation of root filled teeth restored with or without post-and-core systems in a specialist practice setting

AIM: To assess survival rates and complications of root-filled teeth restored with or without post-and-core systems over a mean observation period of >or=4 years. METHODOLOGY: A total of 325 single- and multirooted teeth in 183 subjects treated in a private practice were root filled and restored with either a cast post-and-core or with a prefabricated titanium post and composite core. Root-filled teeth without post-retained restorations served as controls. The restored teeth served as abutments for single unit metal-ceramic or composite crowns or fixed bridges. Teeth supporting cantilever bridges, overdentures or telescopic crowns were excluded. RESULTS: Seventeen teeth in 17 subjects were lost to follow-up (17/325: 5.2%). The mean observation period was 5.2 +/- 1.8 (SD) years for restorations with titanium posts, 6.2 +/- 2.0 (SD) years for cast post-and-cores and 4.4 +/- 1.7 (SD) years for teeth without posts. Overall, 54% of build-ups included the incorporation of a titanium post and 26.5% the cementation of a cast post-and-core. The remaining 19.5% of the teeth were restored without intraradicular retention. The adjusted 5-year tooth survival rate amounted to 92.5% for teeth restored with titanium posts, to 97.1% for teeth restored with cast post-and-cores and to 94.3% for teeth without post restorations, respectively. The most frequent complications included root fracture (6.2%), recurrent caries (1.9%), post-treatment periradicular disease (1.6%) and loss of retention (1.3%). CONCLUSION: Provided that high-quality root canal treatment and restorative protocols are implemented, high survival and low complication rates of single- and multirooted root-filled teeth used as abutments for fixed restorations can be expected after a mean observation period of >or=4 years.

A study of the fate of the buccal wall of extraction sockets of teeth with prominent roots

The objective of this investigation was to determine the fate of thin buccal bone encasing the prominent roots of maxillary anterior teeth following extraction. Resorption of the buccal plate compromises the morphology of the localized edentulous ridge and makes it challenging to place an implant in the optimal position for prosthetic restoration. In addition, the use of Bio-Oss as a bone filler to maintain the form of the edentulous ridge was evaluated. Nine patients were selected for the extraction of 36 maxillary anterior teeth. Nineteen extraction sockets received Bio-Oss, and seventeen sockets received no osteogenic material. All sites were completely covered with soft tissue at the conclusion of surgery. Computerized tomographic scans were made immediately following extraction and then at 30 to 90 days after healing so as to assess the fate of the buccal plates and resultant form of the edentulous sites. The results were assessed by an independent radiologist, with a crest width of 6 mm regarded as sufficient to place an implant. Those sockets treated with Bio-Oss demonstrated a loss of less than 20% of the buccal plate in 15 of 19 test sites (79%). In contrast, 12 of 17 control sockets (71%) demonstrated a loss of more than 20% of the buccal plate. In conclusion, the Bio-Oss test sites outperformed the control sites by a significant margin. No investigator was able to predict which site would be successful without the grafting material even though all were experienced clinicians. This leads to the conclusion that a patient has a significant benefit from receiving grafting materials at the time of extraction.

Transcrestal sinus floor elevation: report of a case series

The technique of the osteotome-mediated transcrestal sinus floor elevation is described in a series of case reports. Fifty-five patients received a total of 66 implants over a period of 6 years. Bio-Oss was added in more than 60% of cases to increase the stability of the lifted area. The surgical procedure appeared to be a safe method that was well supported by the patients. It was applied for different prosthetic indications in partially and completely edentulous situations. The survival rate of the implants during the healing phase was 98.5%, and it was 100% after loading. The patients' responses to the Summers technique were evaluated by means of short interviews and visual analog scales (VAS), and the answers were compared with those from a group of patients who had received implants in the same location during the same period but without the osteotome technique. The answers regarding pain were not different between the groups. However, significantly more patients who had received the implants by means of the osteotome technique judged the surgical procedure as highly uncomfortable. It is concluded that patients need to be well prepared for the procedure.

Specialisation and specialist education in prosthetic dentistry in Europe

This presentation reports on the results of a meeting of prosthodontists from selected European countries. The aim of the meeting was to analyse and promote specialisation and specialist education in Prosthetic Dentistry in Europe. Representatives for Europe were selected from the European Prosthodontic Association (EPA) board, the Education and Research Committee of International College of Prosthodontists (ICP), countries with a legally recognised speciality, countries without a recognised speciality but organised training programmes and countries with neither of these situations. Data about specialisation and specialist training in Prosthodontics in Europe was scrutinised and discussed. The programmes for countries with specialist training had relatively similar content, mostly of three years duration. There was strong agreement that a recognised speciality raises the level of care within the discipline for both specialists and non-specialists. In several of the countries where a speciality had been introduced it had been initiated by pressure from public health planning authorities. The conclusions are that from a professional viewpoint an advancement of the speciality over Europe would develop the discipline, improve oral health planning and quality of patient care. A working group for harmonisation was recommended.

3D C-arm as an alternative modality to CT in postmortem imaging: technical feasibility

OBJECT: The aim of our study was to demonstrate the image quality of the new device using human cadavers, extending the horizon of available imaging modalities in forensic medicine. MATERIALS AND METHODS: Six human cadavers were examined, revealing C-arm data sets of the head, neck thorax, abdomen and pelvis. High-resolution mode was performed with 500 fluoroscopy shots during a 190 degrees orbital movement with a constant tube voltage of 100 kV and a current of 4.6 mA. Based on these data sets subsequent three-dimensional reconstructions were generated. RESULTS: Reconstructed data sets revealed high-resolution images of all skeletal structures in a near-CT quality. The same image quality was available in all reconstruction planes. Artefacts caused by restorative dental materials are less accentuated in CBCT data sets. The system configuration was not powerful enough to generate sufficient images of intracranial structures. CONCLUSION: After the here-demonstrated encouraging preliminary results, the forensic indications that would be suitable for imaging with a 3D C-arm have to be defined. Promising seems the visualization local limited region of interest as the cervical spine or the facial skeleton.

Early implant placement following single-tooth extraction in the esthetic zone: biologic rationale and surgical procedures

Early implant placement is one treatment option for implant therapy following single-tooth extraction in the anterior maxilla. The surgical technique presented here is characterized by tooth extraction without flap elevation, a 4- to 8-week soft tissue healing period, implant placement in a correct three-dimensional position, simultaneous contour augmentation on the facial aspect with guided bone regeneration using a bioabsorbable collagen membrane combined with autogenous bone chips and a low-substitution bone filler, and tension-free primary wound closure. The surgical step-by-step procedure is presented with a case report. In addition, the biologic rationale is discussed.

Zirconia for teeth and implants

This case series reports on the use of nonsilica-based high-strength full ceramics for different prosthetic indications. Fifty-two consecutive patients received tooth- or implant-supported zirconia reconstructions during a 2-year period. The observation period for reexamination was 12 to 30 months. The most frequent indications were single crowns and short-span fixed partial dentures. A few implant superstructures were screw-retained, whereas all remaining restorations were cemented on natural teeth or zirconia implant abutments. Clinical examination included biologic (probing depths, bleeding on probing) and esthetic (Papilla Index) parameters, as well as technical complications. No implant was lost or caused any problems, but two teeth were lost after horizontal fracture. Overall, the periodontal parameters were favorable. Fractures of frameworks or implant abutments were not observed. Abutment-screw loosening occurred once for one premolar single crown. Furthermore, five implant crowns in the posterior region exhibited chipping of the porcelain veneering material. With regard to esthetics, no reconstructions were considered unacceptable, but three crowns were remade shortly after delivery. In this short-term study, it was observed that biologic, esthetic, and mechanical properties of zirconia were favorable, and the material could be used in various prosthetic indications on teeth or implants.

Ultra-high-resolution dual-source CT for forensic dental visualization-discrimination of ceramic and composite fillings

Dental identification is the most valuable method to identify human remains in single cases with major postmortem alterations as well as in mass casualties because of its practicability and demanding reliability. Computed tomography (CT) has been investigated as a supportive tool for forensic identification and has proven to be valuable. It can also scan the dentition of a deceased within minutes. In the present study, we investigated currently used restorative materials using ultra-high-resolution dual-source CT and the extended CT scale for the purpose of a color-encoded, in scale, and artifact-free visualization in 3D volume rendering. In 122 human molars, 220 cavities with 2-, 3-, 4- and 5-mm diameter were prepared. With presently used filling materials (different composites, temporary filling materials, ceramic, and liner), these cavities were restored in six teeth for each material and cavity size (exception amalgam n = 1). The teeth were CT scanned and images reconstructed using an extended CT scale. Filling materials were analyzed in terms of resulting Hounsfield units (HU) and filling size representation within the images. Varying restorative materials showed distinctively differing radiopacities allowing for CT-data-based discrimination. Particularly, ceramic and composite fillings could be differentiated. The HU values were used to generate an updated volume-rendering preset for postmortem extended CT scale data of the dentition to easily visualize the position of restorations, the shape (in scale), and the material used which is color encoded in 3D. The results provide the scientific background for the application of 3D volume rendering to visualize the human dentition for forensic identification purposes.

STATE-AND-TRANSITION MODELING AND ADAPTIVE MANAGEMENT: TOOLS FOR FUTURE CO-DEVELOPMENT OF MADAGASCAR’S NATURAL RESOURCES AND PEOPLE

Madagascar’s terrestrial and aquatic ecosystems have long supported a unique set of ecological communities, many of whom are endemic to the tropical island. Those same ecosystems have been a source of valuable natural resources to some of the poorest people in the world. Nevertheless, with pride, ingenuity and resourcefulness, the Malagasy people of the southwest coast, being of Vezo identity, subsist with low development fishing techniques aimed at an increasingly threatened host of aquatic seascapes. Mangroves, sea grass bed, and coral reefs of the region are under increased pressure from the general populace for both food provisions and support of economic opportunity. Besides purveyors and extractors, the coastal waters are also subject to a number of natural stressors, including cyclones and invasive, predator species of both flora and fauna. In addition, the aquatic ecosystems of the region are undergoing increased nutrient and sediment runoff due, in part, to Madagascar’s heavy reliance on land for agricultural purposes (Scales, 2011). Moreover, its coastal waters, like so many throughout the world, have been proven to be warming at an alarming rate over the past few decades. In recognizing the intimate interconnectedness of the both the social and ecological systems, conservation organizations have invoked a host of complimentary conservation and social development efforts with the dual aim of preserving or restoring the health of both the coastal ecosystems and the people of the region. This paper provides a way of thinking more holistically about the social-ecological system within a resiliency frame of understanding. Secondly, it applies a platform known as state-and-transition modeling to give form to the process. State-and-transition modeling is an iterative investigation into the physical makeup of a system of study as well as the boundaries and influences on that state, and has been used in restorative ecology for more than a decade. Lastly, that model is sited within an adaptive management scheme that provides a structured, cyclical, objective-oriented process for testing stakeholders cognitive understanding of the ecosystem through a pragmatic implementation and monitoring a host of small-scale interventions developed as part of the adaptive management process. Throughout, evidence of the application of the theories and frameworks are offered, with every effort made to retool conservation-minded development practitioners with a comprehensive strategy for addressing the increasingly fragile social-ecological systems of southwest Madagascar. It is offered, in conclusion, that the seascapes of the region would be an excellent case study worthy of future application of state-and-transition modeling and adaptive management as frameworks for conservation-minded development practitioners whose multiple projects, each with its own objective, have been implemented with a single goal in mind: preserve and protect the state of the supporting environment while providing for the basic needs of the local Malagasy people.

THE FANNED FLAMES OF DISCONTENT: A SOLIDARITY-INSPIRED HISTORY OF THE IDENTITY/IDEOLOGY, CULTURAL HISTORY, AND RHETORICAL STRATEGIES OF THE WOBBLIES DURING THE 1916 MINNESOTA IRON ORE STRIKE

Rooted in critical scholarship this dissertation is an interdisciplinary study, which contends that having a history is a basic human right. Advocating a newly conceived and termed, Solidarity-inspired History framework/practice perspective, the dissertation argues for and then delivers a restorative voice to working-class historical actors during the 1916 Minnesota Iron Ore Strike. Utilizing an interdisciplinary methodological framework the dissertation combines research methods from the Humanities and the Social Sciences to form a working-class history that is a corrective to standardized studies of labor in the late 19th and early 20th centuries. Oftentimes class interests and power relationships determine the dominant perspectives or voices established in history and disregard people and organizations that run counter to, or in the face of, customary or traditional American themes of patriotism, the Protestant work ethic, adherence to capitalist dogma, or United States exceptionalism. This dissertation counteracts these traditional narratives with a unique, perhaps even revolutionary, examination of the 1916 Minnesota Iron Ore Strike. The intention of this dissertation's critical perspective is to poke, prod, and prompt academics, historians, and the general public to rethink, and then think again, about the place of those who have been dislocated from or altogether forgotten, misplaced, or underrepresented in the historical record. Thus, the purpose of the dissertation is to give voice to historical actors in the dismembered past. Historical actors who have run counter to traditional American narratives often have their body of "evidence" disjointed or completely dislocated from the story of our nation. This type of disremembering creates an artificial recollection of our collective past, which de-articulates past struggles from contemporary groups seeking solidarity and social justice in the present. Class-conscious actors, immigrants, women, the GLBTQ community, and people of color have the right to be remembered on their own terms using primary sources and resources they produced. Therefore, similar to the Wobblies industrial union and its rank-and-file, this dissertation seeks to fan the flames of discontented historical memory by offering a working-class perspective of the 1916 Strike that seeks to interpret the actions, events, people, and places of the strike anew, thus restoring the voices of these marginalized historical actors.