Background. An online research network was set up among 11 dentists and 2 researchers in Montreal to test the feasibility of data collection over one year. Objectives. We evaluated the pilot participants' experiences and their perspectives regarding its potential utility. Methods. One-on-one qualitative interviews with 4 researchers, 4 dentists, and 3 policy makers. Interviews were recorded on audiotape and transcribed for coding and interpretation. Results. Although feasibility of data collection was evident in the pilot results; qualitative data revealed the limitations of the pilot, the unmet expectations, and the lack of impact of research findings. In terms of potential utility; the participants expressed interest in research, online communication and continuing education. Qualitative analysis revealed differences in perspectives and shared interests among the participants. Conclusion. An online research network can reduce the gap between research and practice. However, to attract participants, it must consider the needs and expectations of those involved.

Despite implant-supported overdentures' advantages over conventional dentures, edentulous patients often refuse dental implants for reasons that may be related to fear. Objective. The purpose of this study was to uncover and explain the various forms and sources of dental implant-related fear among edentulous patients. Methods. A convenient sample of 8 edentulous/semi-edentulous participants was used. Participants were recruited from a current study at McGill University's Faculty of Dentistry, posting of recruitment flyers, and local homes and community centers for seniors. One-on-one interviews were conducted in Montreal from March 2005 to February 2006, transcribed verbatim, and coded into multiple theme-based sections. Results. Three categories of implant-related fear were identified: (1) fear of dental implant surgery; (2) fear of the recovery period; and (3) miscellaneous fears. As well, four main sources of dental implant-related fear were uncovered: (1) past negative experiences at the dentist; (2) "horror stories" of dental implant surgery; (3) having relatively little knowledge of dental implants; and (4) poor dentist-patient relationship. Discussion. The various forms of dental implant-related fear seem to play a substantial role in influencing a patient's decision to undergo implant surgery.

Objectives: To systematically review the research literature on the relationship between Quality of Life (QoL) and cancer therapy-related oral side-effects in a pediatric population. Methods: A scoping review was conducted using 16 databases (research and grey literature), websites, reference lists, and key journals. Inclusion criteria included studies pertaining to children 0-20 years, in English or French, published from 2000 to 2011. Exclusion criteria included mixed population of adults and children and non-discrete disease categories. Data was independently charted by two reviewers. Results: A total of 1270 articles were identified through the initial search. A rigorous review of abstracts and full text reduced the sample to 82 articles, all of which were categorized through a data extraction process. Data analysis resulted in the following findings: Leukemia studies were predominant. The most common side-effect was mucositis; however, side-effects mostly co-occurred. Twenty-one articles dealt directly with the effect on QoL, citing impacts such as changes in taste, eating, drinking, sleep habits, voice and weight loss. Twenty-five articles examined the long-term effect of treatment on pediatric dentition, showing that resultant caries and malformed teeth can affect eating and speech. Conclusions: Preventive oral care before, during and after cancer therapy can decrease the oral side-effects and improve the QoL of the pediatric patient; however, few studies to date advance recommendations for QoL improvement. This study underscores the need for a dental oncology program in pediatric hospitals. / Objectifs : Examiner systématiquement la littérature en recherche sur les liens entre la Qualité de vie (QV) et les effets secondaires des approches thérapeutiques pour traiter le cancer buccal chez une population pédiatrique. Méthodes: Un survol de la littérature été réalisé en utilisant 16 bases de données (recherche et littérature grise), des sites web, des listes de référence et des revues-clés. Critères d'inclusion : études portant sur une population âgée de 0 à 20 ans, publiées en anglais ou en français entre 2000 et 2011 inclusivement. Critères d'exclusion : études concernant une population mixte d'enfants et d'adultes et études d'enfants ayant plus d'un diagnostique. Les données ont été recueillies indépendamment par deux chercheurs; 1270 articles ont été repérés dans un premier survol. Un examen rigoureux des résumés et textes intégraux permit de réduire l'échantillon à 82 articles, par la suite classés à travers un processus d'extraction des données. Résultats d'analyse: Les études sur la leucémie étaient prédominantes. Le plus commun des effets secondaires était la mucosité, mais la plupart des effets secondaires survenaient en cooccurrence. Vingt-et-un articles traitent directement des effets sur la qualité de vie, citant des impacts tels une modification du sens du goût, des changements dans les habitudes alimentaires (e.g. boire et manger) et dans celles du sommeil, des pertes de poids ainsi qu'une modification de la voix. Vingt-cinq articles examinaient l'effet à long terme des traitements sur la dentition pédiatrique et démontrent que la carie et les malformations dentaires qui en résultent peuvent affecter l'alimentation et la parole. Conclusions : Des soins préventifs oraux avant, pendant et après le traitement pour le cancer peuvent diminuer les effets secondaires oraux et améliorer la qualité de vie. Cette étude souligne la nécessité d'un programme d'oncologie dentaire dans les hôpitaux pédiatriques.

No description available.

No description available.

Patients suffering from severe COPD encounter frequent episodes of exacerbations. The anatomical continuity between the oral cavity and the lung makes it a potential reservoir for respiratory pathogens that could be aspirated and cause the exacerbations. The objective of this pilot study was to determine the association between the oral health, oral hygiene in particular and the frequency of exacerbations. The study included 55 patients with severe COPD. Data were collected using various questionnaires and examinations. The results showed that poor oral hygiene was correlated significantly with the increase in number of exacerbations. There was a trend towards bad oral health in patients with high frequency of exacerbations however it was not significantly different between the two groups of low and high frequency of exacerbations. The results of bivariate and multiple logistic regression showed no statistical significant association between oral hygiene status and the frequency of exacerbations.

Matrix Gla Protein (MGP) inhibits mineralization of arteries and cartilage. To determine its mineral-inhibiting potential in hard tissues, MGP was ectopically expressed in bones and teeth of mice using an osteoblast/odontoblast-specific 2.3kb proximal promoter for type 1 collagen. Mandibles and long bones of Col1a1-Mgp mice and wild-type littermates were analyzed by Faxitron(TM) radiography, PIXImus(TM) dual-energy x-ray absorptiometry (DEXA) and micro-computed tomography (mu-CT). In addition, light microscopy (LM) and transmission electron microscopy (TEM) were performed. While bone and tooth extracellular matrices (ECMs) appeared normally established in Col1a1-Mgp mice, examination of the mineral phase by radiography, DEXA and mu-CT, together with histological mineral localization by LM after von Kossa staining of undecalcified tissue sections, and by TEM, revealed massive hypomineralization of bone and tooth ECMs. In the skeleton of Col1a1-Mgp mice, alveolar bone of the mandible was most heavily affected (compared to long bones), showing a 50% increase in the unmineralized osteoid volume compared to wild-type littermates. For teeth, mineralization was virtually absent in root dentin of both incisors and molars, and absent in molar cellular cementum, whereas crown dentin showed localized "breakthrough" areas of mineralization. Acellular cementum formation and mineralization was absent in the Col1a1-Mgp mice. Immunohistochemical staining of bone and tooth ECM proteins in Col1a1-Mgp mice showed variations in staining relative to wild-type tissues, with immunostaining generally restricted to areas of mineralization. In conclusion, these results confirm in vivo that ECM proteins can act as inhibitors of bone and tooth mineralization.

Background: Oral cancer has high incidence and mortality rates in both the developed and developing world. Its main risk factors are tobacco and alcohol consumption and, in India, paan chewing habits. Although socioeconomic position (SEP) has been associated with oral cancer, no studies have assessed this association using life course SEP in an Indian population. Objective: To estimate the extent to which life course SEP is an independent risk factor for oral cancer and how much of this association is explained by behavioural habits and oral health related factors in a sample of Indian subjects. Methods: Data from 200 oral cancer cases and 150 controls were drawn from an ongoing hospital-based case-control study: HeNCe Life (Head and Neck Cancer Life course) study. Detailed information regarding SEP, behavioural and oral health factors over the life course was collected using a questionnaire and a life grid technique. Data analysis involved descriptive and logistic regression analysis. Results: Subjects who were in low SEP throughout their lives were at significant risk for oral cancer (OR=5.81, 95% CI: 2.90-11.64) when compared to those who spent their lives in high SEP. The addition of behavioural and oral health factors into the models attenuated this association (OR= 2.08, 95% CI: 0.89-4.89 for low SEP compared to high SEP). However, low lifetime SEP was still related to an increased risk of oral cancer. Conclusion: Low life course SEP is a significant risk factor for oral cancer in this population. / Introduction: Le cancer oral présente des taux d'incidence et de mortalité élevés, à la fois dans les pays développés et ceux en voie de développement. Ses facteurs de risque principaux sont la consommation de tabac et d'alcool et, en Inde, les habitudes de mâchage. Bien que la position socioéconomique (PSE) ait été associée avec le cancer oral, aucune étude n'a encore évalué cette association en utilisant la PSE tout au long de la vie chez une population indienne. Objectif: Estimer le degré auquel la PSE tout au long de la vie est un facteur de risque indépendant pour le cancer oral et à quel point cette association est expliquée par des habitudes comportementales et des facteurs reliés à la santé buccodentaire dans un échantillon de sujets indiens. Méthode: Des données portant sur 200 cas de cancer oral et 150 témoins ont été tirées d'une étude cas-témoins en cours dans les hôpitaux: l'étude HeNCe Life (Head and Neck Cancer Life course). De l'information détaillée concernant la PSE, des facteurs comportementaux et de santé buccodentaire tout au long de la vie a été recueillie à l'aide d'un questionnaire et de la technique de la grille de vie. L'analyse des données impliquait des analyses descriptives et de régression logistique. Résultats: Les sujets qui étaient dans une PSE faible tout au long de leur vie avaient un risque significativement plus élevé d'être diagnostiqué d'un cancer oral (RC=5.81, IC 95%: 2.90-11.64) comparativement à ceux qui ont vécu leur vie dans une PSE élevée. L'ajout de facteurs comportementaux et de santé buccodentaire aux modèles a atténué cette association (RC= 2.08, IC 95%: 0.89-4.89 pour une SEP faible comparativement à une PSE élevée). Cependant, la PSE au cours de la vie est demeurée reliée à un risque accru de cancer oral. Conclusion: Une PSE faible tout au long de la vie est un facteur de risque significatif de cancer oral dans cette population.

The aim of this study is to compare, with regard to volume maintenance and viability of the grafted bone, three different types of autogenous bone grafts. The three types of autografts with different embryonic origin and cellularity are; cancellous endochondral, cortical endochondral and cortical membranous bone. / The endochondral bone was harvested from the ilium and the membranous bone from the cranium, of New Zealand White rabbits. The grafts were applied to the mandible in an onlay fashion and were stabilized by a titanium mesh. The control group consisted of a blood clot under the titanium mesh. / Micro CT and histologic analysis were performed at 6 and 12 weeks after grafting. The cortical membranous bone graft had a greater volume of bone compared to both endochondral groups. The difference in volume between the two endochondral groups was not statistically significant. These results suggest a role for the embryonic origin of bone in the volume maintenance of the grafts. / The osteoblast and osteoblast counts were used to assess the viability of the grafts. The cancellous endochondral group had the highest number of cells followed by the cortical endochondral and then the cortical membranous. The cortical bone grafts seem to be less viable compared to the cancellous group.

Bone formation is an osteoblast-mediated process that is controlled by systemic factors such as hormones, growth factors and local cues that arise from the extracellular matrix (ECM). Bone ECM is elaborated by osteoblasts and therefore they can control their own activity. The ultimate goal of bone matrix formation is to elaborate an extracellular network, consisting mainly of fibronectin and collagen type I, that is capable of mineralizing and forming a strong tissue with appropriate tensile and elastic properties. This thesis describes studies that link transglutaminases (TGs), the protein cross-linking enzymes to type I collagen matrix deposition, osteoblast differentiation and bone formation. Findings here show that MC3T3-E1 osteoblasts require TG-activity for differentiation and proper production of collagenous matrices. We also show that osteoblasts produce two transglutaminase enzymes, transglutaminase 2 (TG2) and Factor XIIIA (FXIIIA), which are both expressed during osteoblast differentiation. The work further defines the roles of the two TGs in osteoblasts and shows that FXIIIA is the main TG-enzyme with transamidating activity in osteoblasts' ECM. Production of FXIIIA is induced during osteoblast differentiation and is externalized to the cell surface, then secreted to the ECM. TG2 was mainly found on the cell surface of osteoblasts with no transamidating activity; however, it is co-localized with FXIIIA on the cell surface. Studies conducted with chemical inhibitors, TG-substrates and activity probes suggest that TG-activity is required for osteoblast differentiation at three different levels. First, by positively affecting microtubule dynamics, delivery and fusion of secretory vesicles carrying cellular collagen type I to the plasma membrane. Second, by promoting fibronectin matrix deposition and collagen type I secretion. And third, by stabilizing the interaction between fibronectin and collagen type I in the ECM. Furthermore, we demonstrated that tubulin and fibronectin are candidate substrates for FXIIIA in osteoblasts. In summary, our studies are the first to describe FXIIIA transglutaminase expression in osteoblasts in vitro and in vivo, and first to link it to collagen secretion and osteoblast differentiation. Furthermore, these studies were the first to suggest a role for cellular FXIIIA in microtubule dynamics. We conclude that transglutaminase activity arising from FXIIIA can regulate osteoblast differentiation affecting extracellular matrix deposition. / La formation et le développement de l'os est un processus complexe dirigé par les ostéoblastes. Contrôlés par des hormones systémiques, des cytokines et d'autres facteurs locaux, les ostéoblastes sécrètent et assemblent la matrice extracellulaire (MEC) des tissus osseux. L'aboutissement de ce processus sera la génération d'un réseau extracellulaire constitué notamment de la fibronectine et du collagene de type I qui va se minéraliser en formant le tissu dur de l'os avec d'excellent propriétés mécaniques. Cette thèse présente des études liées aux transglutaminases (TGs) – une classe des enzymes responsables de la polymérisation (cross-linking) des protéines et d'autres composée biomacromoléculaires - en relation avec le collagène de type I secrété pendant l'élaboration de la MEC, la différentiation des ostéoblastes et l'élaboration du tissu osseux. Les principaux résultats de ces études portent sur l'observation que l'activité polymérisante de la TG est un facteur crucial pour la différentiation des cellules ostéoblastiques MC3T3-E1 et pour la production normale de la matrice collagénique. Un résultat essentiel de la présente recherche porte sur la découverte que les ostéoblastes synthétisent deux types d'enzymes TG, i.e. la transglutaminase 2 (TG2) et le facteur XIIIA (FXIIIA), qui sont tous les deux secrétés pendant la différentiation des ostéoblastes. Les résultats suivants éclaircirent les rôles des deux enzymes TG (TG2 et FXIIIA) dans l'activité des ostéoblastes en montrant que c'est le FXIIIA qui est l'enzyme TG dominante avec une activité de transamidation importante dans la MEC des ostéoblastes. FXIIIA est produit pendant la différentiation des ostéoblastes en s'externalisant vers la surface des cellules pour être par la suite sécrété dans la MEC. L'enzyme TG2 a été localisé seulement à la surface des cellules osteoblastiques. Même si le TG2 a été trouvé colocalisé avec le FXIIIA à la surface des cellules, aucune activité de transamidation n'est identifiée pour le TG2. Des études comportant des inhibiteurs chimiques, de substrats TG et de sondes d'activité TG suggèrent que l'activité TG est nécessaire pour la différentiation des ostéoblastes sur trois plans distincts, à savoir : (i) par une action bénéfique sur la dynamique des microtubules, l'acheminement et la fusion des vésicules sécrétoires qui transportent le collagène I cellulaire vers la membrane plasmatique; (ii) par l'accélération du dépôt de la matrice de fibronectine et la sécrétion du collagène de type I; (iii) par la stabilisation de l'interaction de la fibronectine avec le collagène I dans la MEC. De plus, nous avons démontré que la tubuline and la fibronectine ce sont de candidats substrat pour le facteur FXIIIA dans les ostéoblastes. En résumé, notre recherche décrit pour la première fois l'expression de l'enzyme transglutaminase FXIIIA dans les ostéoblastes, tant in vitro qu'in vivo, en corrélant l'expression du FXIIIA à la sécrétion et la différentiation des ostéoblastes. De plus, notre étude est la première en attribuant un rôle au facteur FXIIIA relative à la dynamique des microtubules. On conclut de notre étude que l'activité transglutaminase du facteur FXIIIA exerce une influence décisive dans les processus de différentiation des ostéoblastes avec un effet régulateur crucial à la sécrétion et au dépôt de la matrice extracellulaire.