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Introduction: the diagnosis of drowning is essentially based on the diatom test in the bone marrow. However, this test is currently very controversial because of the many biases and external factors that can influence it, in particular the phenomenon of passive diffusion. Materials and methods: we were interested in the existence of a passive diffusion in pork femurs immersed in an aquarium enriched in diatoms. At the same time, an alternative to the diatom test in the dental pulp was tested according to the same protocol as for the femurs in order to demonstrate the absence of passive diffusion in the dental pulp. Results: in 2 months of immersion and 48 slides made from samples of pork bone marrow, 36 slides revealed the presence of diatoms. For the same immersion time and 24 slides made from dental pulp samples, 3 slides were positive. Discussion: the results in pork bone marrow allowed us to significantly conclude the presence of passive diffusion. The results on dental pulp are encouraging but did not allow us to conclude significantly on an absence of passive diffusion due to the sample size.; Introduction : le diagnostic de noyade repose essentiellement sur le test de la diatomée au sein de la moelle osseuse. Or ce test est à ce jour très controversé du fait des nombreux biais et facteurs externes qui peuvent l’influencer et notamment le phénomène de diffusion passive. Matériels et méthodes : nous nous sommes intéressés à l’existence de la diffusion passive au sein de fémurs de porc immergés dans un aquarium enrichi en diatomées. En parallèle, une alternative du test de la diatomée au niveau de la pulpe dentaire a été testée selon le même protocole que pour les fémurs afin de démontrer l’absence de diffusion passive dans la pulpe dentaire. Résultats : en 2 mois d’immersion et 48 lames réalisées à partir des prélèvements de moelle osseuse de porc, 36 lames ont révélé la présence de diatomées. Pour le même temps d’immersion et 24 lames réalisées à partir des prélèvements de pulpe dentaire, 3 lames se sont révélées positives. Discussion : les résultats au sein de la moelle osseuse de porc nous ont permis de conclure de manière significative à la présence d’une diffusion passive. Les résultats sur la pulpe dentaire sont encourageants mais ne nous ont pas permis de conclure significativement à une absence de diffusion passive dû à une taille d’échantillon trop faible.

A biochemical study of dental pulp of calves has been performed concerning:a) peroxydabilityb) A, E, C vitamins contentc) glutation (GSH) contentd) presence of paramagnetic compoundse) phosphorylation ratioThe dental pulp from incisives of 5 months old calves has been preserved. Immediately after decapitation the pulp was immersed in liquid nitrogen. Chromatographie (HPLC) and spectroscopic (NMR-ESR) techniques have been used.GSH in dental pulp are present and dosable (4.56 +/-0.08 n moles/mg prot.) and GSSG (1.05 +/-0.01 n moles/mg prot.).Because of blood traces in the extracted pulps, the AA. have determined the hemoglobin (Hb) dosage and GSH of erythrocytary derivation (Fig. 1).After deduction of GSH of erythrocytary derivation, the GSH really present in the pulp was 4.41 n moles/mg prot. and the GSSG was 0.90 n moles/mg prot.Peroxydability of the dental pulp has been evaluated with Lowry method with dental pulp homogenate and rat liver homogenate (see Table 1).The ESR spectre shows 4 resonances with the following values: g. 2.24 - 2.04 - 2.00 - 1.97; there are some free intermediary radicals (gr. - 2.00) (Fig.2).The NMR spectre shows the presence of ATP (0.22 n moles/g) of inorganic phosphate (16.58 n moles g) (Fig.3).The pulp seems to have a lot of antioxydant factors. The next researches will be to study E, A and C vitamins concentrations. This high presence of GSH and GSSG may be an embryonary peculiarity., Une étude biochimique de la pulpe dentaire a été entreprise pour étudier les propriétés antioxydantes et leurs interactions avec le métabolisme énergétique et les équilibres redox de la pulpe dentaire de veau. Le GSH réduit et oxydé (GSSG) a été mesuré et la spectroscopie avec ESR (Electron Spin Résonance) a été utilisée pour la recherche des substances paramagnétiques et la résonance magnétique nucléaire (NMR) pour la détermination des métabolites phosphorylés de petit poids moléculaire. Après la soustraction de la quantité de GSH érythrocytaire, le GSH présent dans la pulpe est resté identique 4,41 n moles/mg prot. (GSH) et 0.90 n moles/mg n moles/mg prot. (GSSG). La péroxydation lipidique de la pulpe dentaire a été étudiée. Le spectre ESR montre 4 résonances, respectivement de valeurs de G de 2.24, 2.04, 2.00, 1.97.L’analyse des résultats montre l’existence d’une petite quantité de radicaux libres intermédiaires (g-2.00) dépendant du métabolisme tissulaire. Le spectre NMR a montré la présence d’ATP (0.22 n moles/g) et de phosphate inorganique (16.50 n moles/g).

Tissue regeneration is a rapidly expanding field in dentistry and its main objective is to replace damaged or absent dental tissue. There are different approaches based on the regeneration of a particular type of tissue constituting the tooth (enamel, dentin, pulp), the periodontium (cement, alveolar bone, periodontal ligament) or even an entire tooth. In this perspective, the vascularization and innervation of the tooth are essential for the maintenance of homeostasis and the response to nociceptive stimuli. This work revolves around three main themes: the regeneration of the tooth and its innervation, the preparation of a bone site conducive to its development and finally its eruption in the oral cavity., La régénération tissulaire est un domaine en pleine expansion en odontologie et a pour principal objectif de remplacer les tissus dentaires lésés ou absents. Il existe différentes approches basées sur la régénération d'un type tissulaire particulier constituant la dent (émail, dentine, pulpe), du parodonte (cément, os alvéolaire, ligament alvéolo-dentaire) ou encore d'une dent entière. Dans cette perspective, la vascularisation et l'innervation de la dent sont essentielles pour le maintien de l'homéostasie et la réponse aux stimuli nociceptifs. Ce travail de thèse s’articule autour de trois grandes thématiques : la régénération de la dent et son innervation, la préparation d’un site osseux propice à son développement et enfin son éruption dans la cavité buccale, la régénération tissulaire n’ayant de sens que lorsque l’organe est fonctionnel.

Le logiciel P@thopulp est une aide à l’apprentissage pour les étudiants de DFASO1, des maladies pulpaires et périapicales selon la démarche par critères diagnostiques. Il ne possède cependant pas de précision sur la réalisation des tests diagnostiques. Ce projet vise à compléter les propositions d’apprentissage du logiciel P@thopulp, en créant un module d’enseignement des modalités de réalisation des tests diagnostiques. La méthode est basée premièrement sur une revue bibliographique puis deuxièmement sur la réalisation d’une série de vidéos illustrant les conditions dans lesquelles ces tests doivent être appliqués selon les résultats de la revue bibliographique. Une évaluation des documents produits a été menée auprès de 20 étudiants de 5ème et 6ème année avec un questionnaire. 13 articles ont été inclus dans la revue bibliographique, permettant de mettre en lumière les modalités de réalisation des tests diagnostiques. Une série de vidéos, respectant les modalités de la bibliographie a été réalisée. L’évaluation auprès des étudiants a confirmé l’intérêt des documents, 19 des 20 étudiants interrogés auraient aimé pouvoir consulter ces documents quand ils avaient utilisé P@thopulp. Un faible nombre d’articles précisaient les modalités de réalisation des tests diagnostiques. La faiblesse de ces descriptions peut avoir un impact sur la formation des praticiens qui appliquent des tests dans des conditions très différentes, ce qui peut participer à des erreurs diagnostiques. Ce travail propose une iconographie des tests cliniques. L’évaluation de celle-ci faite auprès de 20 étudiants de 5ème et 6ème année en chirurgie dentaire montre qu’elle peut être intégrée dans le logiciel P@thopulp.

Preserving primary teeth is crucial for maintaining the maxillary growth, aesthetics, mastication, and speech and for preventing from abnormal habits. Given the peculiar anatomy of the primary tooth, caries grow faster and more frequently to the pulp. In pediatric dentistry, new methods and enhanced material have been recently released on the market and broadened the field of treatments. In this paper, we review the pulp diseases affecting children and focus on the current root canal therapies that favour the physiological primary tooth loss.Conserver les dents de lait est essentiel pour assurer la croissance des maxillaires, l’esthétique, la mastication et la phonation ainsi que pour prévenir l’apparition de dysfonctions. Vu les particularités anatomiques des dents de lait, la carie progresse toujours plus rapidement et plus fréquemment jusqu’à la pulpe. L’avènement de nouvelles techniques et de nouveaux matériaux en dentisterie pédiatrique a élargi nos possibilités thérapeutiques. De même, l’interdiction d’utilisation de certains produits a conduit le pédodontiste à devoir trouver des alternatives de traitement. Le but de cet article est de faire le point sur les pathologies pulpaires chez l’enfant et sur les thérapeutiques endocanalaires actuelles.

Dental research currently explores the potential of cell-based products and tissue engineering protocols to be used as alternatives to usual pulp/dentin and bone therapies. In this context, stem/progenitor cells appear to be particularly appropriate because of their high expansion ability and differentiation potential both in vitro and in vivo. If bone marrow and adipose tissue are considered potential sources of stem/progenitor cells, painful collection protocols, the decline of the amount of stem/ progenitor cells with age, the necessity of general anesthesia, reduced proliferation capacity, and risk of morbidity at the collection site encourage the search for alternative candidates. Human impacted third molars are frequently removed for therapeutic reasons and the loose connective tissue they contain, the dental pulp, appears to be a valuable source of stem/progenitor cells for pulp/dentin and bone engineering. Indeed, it contains various cell populations that exhibit osteo/odontoblastic differentiation capabilities and that can be cryopreserved for periods of time greater than 6 months. Interestingly, human dental pulp cell (HDPC) populations were recently successfully used for regenerating human pulp/dentin and bone. Cell-based products for tissue engineering are now referred to as human cellular tissue-based products or advanced therapy medicinal products, and guidelines from the American Code of Federal Regulation of the Food and Drug Administration (21 CFR Part 1271) and the European Medicines Agency (European Directive 1394/2007) define requirements for appropriate cell production. These ‘‘good manufacturing practices’’ include recommendations regarding laboratory cell culture procedures to ensure optimal reproducibility, efficacy, and safety of the final medicinal product, Ces dernières années, des thérapies à base de cellules mésenchymateuses ont été développées pour améliorer les thérapies qui visent à réparer l'homme et notamment la pulpe dentaire. Dans ce contexte, la dent apparait comme la source de cellules mésenchymateuses, souches ou progénitrices, permettant de réparer la pulpe dentaire. En effet, la pulpe dentaire est facile d'accès et les cellules pulpaires présentent un fort potentiel de différenciation. Actuellement, les différents organismes de contrôle recommandent d'utiliser des procédures standardisées pour l'isolement, le stockage et l'expansion des cellules en culture pour garantir une sécurité et une reproductibilité optimale lorsque les cellules sont utilisées en culture cellulaire. Cependant, la plupart des procédures utilisées pour la production de cellules à partir de la pulpe dentaire ne sont pas entièrement satisfaisante, car elles peuvent altérer les propriétés biologiques et la qualité des cellules. En effet, les procédures d'isolement cellulaire, d'enrichissement, de cryopréservation et d'amplification pendant de nombreux passages dans des milieux contenant des produits d'origine animale ou humaine sont connues pour affecter le phénotype des cellules, la viabilité, la prolifération et les capacités de différenciation. Ce travail de thèse s'intéresse à compiler les stratégies actuelles de fabrication de produits cellulaires à partir de la pulpe dentaire, puis il propose de nouveaux protocoles pour améliorer l'efficacité, la reproductibilité et la sécurité de ces nouvelles stratégies thérapeutiques. Ainsi nous avons isolé, amplifié et cryopréservé des cellules de la pulpe dentaire. Grace à un travail d'immunophénotypage, nous avons pu étudier différentes souspopulations à l'intérieur de la population totale. Enfin nous avons montré que ces cellules sont capables de rester congelées pendant plus de 500 jours sans présenter d'anomalies du caryotype et de conserver un potentiel de différenciation ostéo/odontogénique

Vitality loss is an unusual event that can occur before, during or after an orthodontic treatment. It can lead to loss of sensitivity, color change or necrosis of the pulp tissue. Before starting the orthodontic treatment, we have to identify the tooth's risk (injured tooth, included occlusal trauma...). Knowing that, if an endodontic treatment has to be done, it is better to do it before starting orthodontic forces. Lamps do not provide problems except high intensity halogen ones. RPE on children, Le Fort I and mandibular osteotomies, corticotomies, genioplasties are responsible of a transitory ischemia without reaching a pathogen level. Mini-screws or mini-plates may be iatrogenic, if they impact the root. The repair options depend on the delay before removing the miniscrew and the nature of injured tissue.

The dental pulp is prone to severe injuries following a tooth decay or trauma. Conventional recommended therapy is the endodontic treatment, which consists in the removal of all of the dental pulp and filling of the pulp space with an inert material. This treatment leads to a weakening of the tooth and a greater susceptibility to infection.In this work, we have developed an alternative solution, proposing the replacement of the injuried dental pulp by an " pulp equivalent " consisting of mesenchymal stem cells from the pulp seeded in a collagen matrix . We tested this pulp substitut through a model of the molar pulpotomy in rats, ie. the removal of the entire parenchyma of the pulp chamber and preservation of the root vascular network and implantation of the pulp equivalent. Our aim was to determine the fate of pulp stem cells implanted in the tooth by nuclear imaging in the context of developing a cell therapy. The cells were labeled with 111Indium - oxine prior to their implantation. We have shown that the labelling had no effect on the viability and proliferation of pulp cells. The signal tracking was done by single photon emission tomography , coupled with a specific small animal scanner ( NanoSPECT / CT , Bioscan ) weekly for 3 weeks. We demonstrated that the intensity of SPECT signal was directly related to the integrity of the cells, since the lysed labeled cells by isotonic shock showed a rapid decrease in the intensity of labeling . Due to the sensitivity of the chosen imaging method , we have shown the absence of major diffusion cells into the bloodstream from the site of implantation, which could result in a risk of ectopic mineralization related to the implementation of mesenchymal stem cells.Furthermore, the study by histology repair processes and regeneration of the pulp in teeth rat showed abundant proliferation of fibroblast-like cells within the matrix , and the presence of numerous vessels and nerves in matrix cellularized. These results , not observed in the matrices implanted with lysed cells, thus suggesting a feature of the reconstructed tissue and suggested that the pulp cells implanted favored a rapid neovascularization equivalent pulp, presumably by inducing the recruitment of endothelial cells from the residual root vascular network.; La pulpe dentaire est sujette à des lésions sévères faisant suite à une carie dentaire ou à un traumatisme. La thérapeutique conventionnelle préconisée alors est le traitement endodontique, qui consiste en l’exérèse de la totalité de la pulpe dentaire et le comblement de l’espace pulpaire par un matériau inerte. Ce traitement induit une fragilisation de la dent et une plus grande susceptibilité aux infections. Au cours de ce travail, nous avons mis au point une solution alternative, en proposant le remplacement de la pulpe dentaire lésée par une « pulpe équivalente » constituée de cellules souches mésenchymateuses de la pulpe ensemencées dans une matrice de collagène. Nous avons testé ce substitut pulpaire au travers d’un modèle de pulpotomie de la molaire chez le rat, à savoir l’exérèse de la totalité du parenchyme de la chambre pulpaire et conservation du réseau vasculaire radiculaire, où nous avons implanté des « pulpes équivalentes ». Notre objectif étant notamment de déterminer le devenir des cellules souches pulpaires implantées dans la dent grâce à l’imagerie nucléaire, dans ce contexte de développement d’une thérapie cellulaire. Les cellules ont été marquées à l’111Indium-oxine préalablement à leur implantation. Nous avons montré que le marquage n'avait pas d'incidence sur la viabilité et la prolifération des cellules pulpaires. Le suivi du signal s’est fait par tomographie d'émission monophotonique, couplée à un scanner spécifique du petit animal (NanoSPECT/CT, Bioscan), hebdomadairement pendant 3 semaines. Nous avons mis en évidence que l'intensité du signal SPECT était directement liée à l'intégrité des cellules, puisque que les matrices implantées avec des cellules marquées puis lysées par choc isotonique présentaient une diminution rapide de l’intensité du marquage. Grâce à la sensibilité de la méthode d’imagerie choisie, nous avons montré l’absence de diffusion majeure des cellules dans la circulation sanguine à partir du site d'implantation, ce qui pourrait constituer un risque de minéralisation ectopique lié à l’implantation de cellules souches mésenchymateuses. Par ailleurs, l’étude par histologie des processus de réparation et régénération de la pulpe dans les dents de rat a mis en évidence une prolifération abondante de cellules de type fibroblastique au sein des matrices, ainsi que la présence de nombreux vaisseaux et de nerfs dans la matrice cellularisée et à proximité. Ces résultats, non observés dans les matrices implantées avec des cellules lysées, suggéraient donc une fonctionnalité du tissu reconstruit et suggéraient que les cellules pulpaires implantées favorisaient une néovascularisation rapide de la pulpe équivalente, vraisemblablement en induisant un recrutement de cellules endothéliales à partir du réseau vasculaire radiculaire résiduel.

Dentinal sensitivity is a clinical condition daily encountered by practitioners and constitutes the symptoms of dentinal hypersensitivity, a common dental pain affecting on average 30% of the population. However, the management of this pathology is not always effective due to the lack of knowledge particularly concerning the means by which dental nociceptive signals are transduced. The mechanisms underlying dentin sensitivity still remain unclear probably due to the structural and functional complexity of the players including odontoblasts, nerve endings and dentinal fluid running in the dentinal tubules. The unique spatial situation of odontoblasts, ciliated cells in close relationship with nerve terminals, suggests that they could play a pivotal role in the transduction of sensory events occurring within the dentin tissue. Our studies have identified mechano-thermosensitive transient receptor potential ion channels (TRPV1-4, TRPA8, TRPM3, KCa, TREK-1, PC1, PC2) localised on the odontoblastic membrane and at the base of the cilium. They could sense temperature variations or movements of dentinal fluid within tubules. Moreover, several voltage-gated sodium channels confer excitable properties to odontoblasts in response to injection of depolarizing currents. In vivo, these channels co-localize with nerve endings at the apical pole of odontoblasts, and their expression pattern seems to be correlated with the spatial distribution of stretch-activated KCa channels. All these data strengthen the hypothesis that odontoblasts could act as sensor cells able to transmit nociceptive signals. However, how cells sense signals and how the latter are transmitted to axons represent the main issue to be solved.

Stem cells discovery and their potential have led to the emergence of new forms of therapy with the development of bio-engineering cell and tissue methods underlying future medicine. The availability of stem cells and their preservation thus become an issue for everyone's health. Among the different sources of stem cells, those in the dental pulp have the advantage of being pluripotent, they can be cryopreserved and stored for long periods without losing their multiplication and differentiation capacities and finally they are easily accessible. The wisdom or natal teeth extracted for medical reasons are an opportunity for everyone to preserve stem cells for an autologous use. Biobanks authorized and specialized in the preparation and storage of pulp stem cells provide access to autologous regenerative medicine of tomorrow.

The currently available options for tooth-loss are prostheses, implants, or surgery (auto-transplantation). They all have their limitations. The emergence of tissue engineering, 15 years ago, was made possible by a better knowledge of the various stages of dental development, and the mastery of stem cell differentiation. It opened a new alternative approach for tooth regeneration. Even if animal experiments have demonstrated that it was possible to obtain a biological tooth from stem cells, two major issues remain to be discussed. Is it possible to use induced pluripotent stem cells instead of embryonic stem cells, which raise an ethical problem? Is it possible to reproduce a dental crown with an adapted shape and colour? Or should we consider the simpler creation of a biological root secondarily covered by a ceramic prosthesis? Our study mentions the main landmarks and the key cells involved in the embryological development of the tooth, establishes a mapping and a list of the various types of stem cells. It details the various methods used to create a biological implant.

Les facteurs de risques de contaminations croisées des échantillons de tissus destinés à l’étude de l’ADN ancien sont nombreux. La pulpe dentaire étant mieux protégée mais en faible quantité, nous avons mis au point une technique de fracture des différents morphotypes de dents qui nous permet de recueillir la totalité de la pulpe dans des conditions aseptiques. There are numerous risk factors for cross-contamination of tissue samples for DNA. As dental pulp is better protected but small in amount, we have developed a fracture technique for the different dental morphotypes which allows the total recovery of the pulp in aseptic conditions.

An early determination of pulpal vitality is crucial with respect to a correct differential diagnosis of revascularisation or necrosis and its treatment. The use of sensibility tests (cold, heat, electrical pulp test) in combination with X-ray are commonly promoted. However these tests are arbitrary, based on sensations and therefore not always reliable. In such situation the registration of 'real' pulpal blood flow and hence pulp vitality will be more than an added value. The most studied and well documented method is laser Doppler flowmetry (LDF) as it is non invasive, direct and objective. In this article we describe blood flow, LDF and its characteristics, advantages and disadvantages of this method and the newest developments regarding LDF. Despite a low implementation of LDF in Belgium, this technique proved to belong indisputable to the basic assets of a dental clinic. A number of cases are described to demonstrate the efficacy and added value of LDF in assessing tooth vitality.

Three dogs have been used in this experiment. Class V cavities were made in sixty teeth. A pulpal communication was provoked intentionally in these cavities. Teeth were randomly split in 2 groups (30 teeth for each). On first group, the pulp bleeding was stopped until appearance of coagulum on exposed pulp surfaces by means of CO2 laser irradiation (Output Power: 3 W, Pulse duration: 0.1 sec, frequency: 1 Hz, spot size diameter: 0.3 mm, Energy density: 425 J/cm2). Calcium Dihydroxide was deposited followed by a temporary filling (IRM, Dentsply, De Trey, Germany). In the second group, the calcium Dihydroxide was deposited directly on exposed bleed pulp (conventional technique) followed by the same temporary filling. Ten weeks later, all teeth were extracted and prepared for histological study.93% of treated teeth preserved their pulp vitality in the group treated with CO2 laser for direct pulp capping versus 82% in the group treated by conventional technique. The average of the thickness of the dentinal bridge newly formed was 391.5 +/- 33 microm for teeth irradiated with laser and 294.1 +/- 28 microm for teeth treated by conventional technique. The thickness of the dentinal bridge newly formed in teeth treated by means of CO2 laser was 33% more important than in those treated by the conventional technique. Statistical analysis showed a significant difference between the averages of values in all groups (p0.05). To conclude, CO2 Laser use in the direct pulp capping increases significantly the percentage of pulp vitality preservation and the thickness of the dentinal bridge newly formed after pulp exposition.

A rapid diagnostic dipstick test (RDT) that detects Yersinia pestis F1 antigen has been recently applied on 18 putative plague victims exhumed from four archaeological burial sites in southeastern France dating back to the 16(th), 17(th) and 18(th) centuries. The Y. pestis antigen F1 was detected in 12 ancient samples out of 18 (67%). Negative controls confirmed their negativity (100%). Our results emphasize that the detection threshold of the RDT for plague (0.5 ng/ml) is sufficient for a first retrospective diagnosis of Y. pestis infection in ancient remains, and confirm the high specificity and sensitivity of the assay. Double-blind analyses performed by using two different techniques (RDT and 'suicide PCR') led us to the identification of the Y. pestis F1 antigen and the Y. pestis pla and gplD genes. These data provide clear evidence of the presence of Y. pestis in the examined specimens.

Any clinician dreams to obtain the regeneration of the destroyed organ for his patient. In the human being, the regeneration of complex structures is not possible, except the liver and the bone marrow, which can be regenerated because of the presence of adult stem cells in these tissues. The stem cells have two principal properties: they ensure their self-renewal and they have the ability to differentiate into several cellular types. Using specific markers allowing the identification of the stem cells in bone marrow, stem cells were observed in dental pulp tissues. Although the origin, the identification, and the localization of these stem cells of dental pulp remain under consideration, the optimism in research on stem cells permits to believe that the knowledge on dental stem cells will lead to their use in therapeutics.

Dental trauma is a frequent condition which may occur alone or in combination with craniofacial trauma and/or other injuries. Many factors influence the gravity of the trauma and subsequent prognosis including age, anterior state, trauma etiology, treatment and follow up. In order to establish a prudent provisional or definitive expertise, the medical expert must have a panoramic view of the trauma. Time should be taken to consolidate facts and estimate prejudices on sound evidence. In certain cases outcome can be predicted. The medical expert should provide advice and counselling both for the patient and the mandating authority. In this article, iatrogenic dental accidents occurring during anesthesia or extraction will not be discussed.

The reliability of laser Doppler flowmetry in a 2-probe assessment of pulpal blood flow is well known. The purpose of this case report was to determine its use as an exclusive and reliable tool for tooth vitality diagnosis in a long-term follow-up. As a result of a traumatic injury to a 24-years old Caucasian female, tooth pulp vitality was studied in 6 maxillary front teeth over 30 weeks through use of 2-probe laser Doppler flowmetry and current sensitivity tests. A similar assessment was repeated after 228 weeks. Confronted with an alveolar bone fracture with a tooth in the fracture line, one intrusion and several luxated teeth, current sensitivity tests are found not to be so reliable indicators of revascularisation as significant results are given later (7 weeks) compared to laser Doppler flowmetry tests (1 week). A pathway with ischaemia (3 weeks), hyperaemia (7 weeks) and restored blood supply in the pulp measured by laser Doppler flowmetry tests was found and avoided endodontic treatment. Teeth vascularisation evolved normally (228 weeks). Despite a high indication in all sensitivity tests for endodontic treatment, the use of laser Doppler flowmetry tests was clear, more reliable than sensitivity tests and exclusive as denervation was postponed and pulp vascularisation was evident.

Rather easy to perform, pulpotomy of the deciduous teeth is the most frequent endodontic treatment performed on children, but also the most controversial. Based on the amputation of the pulp chamber and the conservation of the inflammation-free root canals, the clinical results can be good, depending on the materials used. In this, calcium hydroxide (Ca(OH)2) as well as zinc-oxide-eugenol (ZOE) have been proven very inflammatory whereas Formocresol (FC) remains the reference even if its clinical toxicity is still reported in literature on a very controversial way. Nevertheless, this was sufficient to trigger and stimulate a search for alternatives, and led to the proposition to use ferric sulfate and even more recently MTA as new bases for the treatment of the pulp stumps after pulp chamber amputation.

Ameloblastic fibro-odontoma is a rare and benign tumor. It usually affects young patients. This report describes the case of a ten year old child presenting an asymptomatic and slow-growing tumor located in the posterior region of the mandible. The course was normal and no recurrence was found after simple enucleation of the tumor.

When bioactive molecules such as bone sialoprotein (BSP), bone morphogenetic protein-7 (BMP-7, also termed OP-1) and chondrogenic Inducing Agents (CIA, A+4 and A-4) were implanted in the pulp of the first upper molars, mineralizations were induced. They were either limited to the formation of a reparative dentinal bridge closing the pulpal wound (CIA A+4), or filled the mesial part of the coronal pulp (BSP), or filled totally the pulp located in the root canal (BMP-7 and CIA A-4). Consequently, these molecules may change in the next future the every day practice in dentistry.

A family of seven siblings is described. The mother and six siblings have been examined, the eldest and youngest of whom suffer from congenital indifference to pain , although both were ticklish, and itched. The functions examined included somatosensory perception thresholds and autonomic functions; perception thresholds were greatly raised in the painfree subjects and to a lesser extent in some other family members, asymmetrically in all cases, being higher in the dominant hand. Painfree Subject 1 also underwent cerebrospinal fluid analysis at age 16, which showed normal B-endorphin levels but undetectable enkephalins. Electrophysiological tests when a child demonstrated notably that most (raised) measured values were lowered by naloxone. Light microscopic sural nerve biopsy performed on painfree Subject 1 in childhood did not suggest any abnormalities other than a thickened nerve sheath. Threshold asymmetry has not been observed in large numbers of subjects without neurological deficits. There were no significant autonomic changes in any tested family member, though there was some asymmetry. It is suggested that the findings may imply a congenital anomaly of the central nervous system which accounts for the somatosensory, biochemical, and electrophysiological abnormalities.

A direct or indirect effect of the intake of medication on the pulp itself has not yet been described in the literature. The effect of local anesthetics on the pulp, on the other hand, has been documented. Although local anaesthesia has been employed in dentistry for many years, most investigations of its action have only considered the effect on the nerves within the pulp using traditional methods. Recently it has become clear that the nerves and blood vessels of the pulp do not act in isolation but are closely related. In this respect it has been shown that there exists a direct relationship between the length of the flow cessation and the concentration of vasoconstrictor used. Therefore care should be taken when using vasoconstrictors especially where pulpal injury is apt to occur when dental procedures such as full crown preparations are performed immediately following a ligamental injection. The anaesthetic efficacy of intraosseous injection is well documented. The effect, however, on the dental pulpal circulation still remains subject of further investigation. Radiotherapy involving the oral cavity and salivary glands and chemotherapy (in a lesser degree) induce alterations in the oral tissues and the salivary gland functions. Some of these side effects are transient. However there are side effects such as the xerostomia which are very drastic for the dentition resulting in radiation caries and dental hypersensitivity. Tooth anomalies in the developing dentition are also described. Due to the rapid progression of the radiation caries a monitoring of the oral cavity with strict application of preventive measurements and systematic follow-up can reduce the incidence of the complications. Unfortunately most of the patients belonging to this group consult with the complications of their radiotherapy and chemotherapy. In this respect endodontic treatment of the severely decayed teeth is an important part of dental treatment. Moreover, extraction is regularly contraindicated as osteoradionecrosis is then one of the major sequels.

Since there is a close relationship between the periodontium and the pulp, formed by the apical foramen, dentinal tubules, lateral and accessory canals, it is evident that both compartments influence one other. In this article, the influence of periodontal disease and its treatment on the dental pulp is described. The review shows that periodontal disease and its treatment, very seldom compromise the vital functions of the pulp, but can cause local pulpal response. A more common reaction is dentinal hypersensitivity. Although there's no clear treatment for dentinal hypersensitivity, this article presents a few guidelines for treatment.

The photoplethysmography allows to pick up the pulse of dental pulp, using an optical electronic device. It is a non-destructive method to appreciate the good health of dental pulp, and it constitutes consequently an interesting assistance to diagnosis.

This study was conducted to determine the incidence of pain during and after root canal treatment. Complete debridement and root canal preparation was performed in first visit. The frequency of pain was recorded and evaluated in 150 patients receiving root canal treatment. Results has shown that incidence of pain was 6.66% root canal preparation in vital teeth and 21% in non-vital teeth (necrosis). Post-obturation pain occurred in 18.75% for vital teeth and 13.15% non-vital teeth (necrosis).

Pulp tissue may suffer from carious invasion, direct or indirect trauma and last but not least from dental treatment. As the general population grows older and retains longer its dentition, teeth will inevitably experience a complex history of multiple episodes of aggressions. It is therefore not surprising that the dental practitioner is confronted more and more with teeth reacting acutely or chronically (in other words, painfully or not) after proper dental treatment. This paper describes the common pathologic and iatrogenic events that may have an effect on the pulpal health status. Preventive endodontic treatment is to be considered in cases of extensive dental treatment.

The smear layer is a direct consequence of instrumentation of the root canal wall. Hand instrumentation as well as ultrasonic instrumentation produce a smear layer on the canal wall. This smear layer is composed of dentine, remnants of pulp tissue and odontoblastic processes and bacteria in an infected canal. Removal of the smear layer is accomplished by the irrigation of root canals with EDTA (17%) followed by NaOCl (5.25%). Permeability of the dentine is increased by the removal of smear layer. In this way the bacteria within the infected tubuli can be more easily destroyed by an intracanal dressing. Whether the removal of smear layer decreases the apical leakage is uncertain. To establish the clinical consequences from removal or preservation of the smear layer, further research is needed.

Tooth infraction and enamel fracture are the most simple traumatic crown lesions. When necessary the lesions can be covered with composite material. Follow-up of the traumatized tooth is necessary since pulp necrosis and obliteration can develop. In case of an uncomplicated fracture involving enamel and dentine immediate protection of the dentinal wound is important for the preservation of tooth vitality. In case of a negative vitality test, an endodontic treatment will be performed in case of a tooth with open apex only when supplemental clinical and or radiological signs of pulp necrosis are present. When a complicated enamel-dentine fracture is present, an endodontic treatment will be performed when root formation is complete. In case of a wide open apex, a pulp capping, partial pulpotomy or cervical pulpotomy will be performed in order to preserve vitality of pulpal tissues at the level of the root. Crown root fractures can be superficial, deep or vertical. In case of a superficial localisation of the fracture line, restoration with composite material or with the fractured tooth segment is indicated. Deep crown-root fractures can only be restored when the fracture line is localized not deeper than at 1/3 of the length of the root. In case of a vertical fracture, extraction is the only possibility. Root fractures on immature teeth are in most cases unilateral and have a good prognosis. In teeth with completed root formation, fractures at the level of the cervix have a poor prognosis. The fractured segment will be removed. Only when the remaining root segment is long enough, this part can be maintained. In case of a fracture at the mid-root level, repositioning and rigid splinting for a period of 8 weeks is necessary. When the tooth becomes non-vital, endodontic treatment is performed on the coronal part. Root fracture in the apical part does not necessary result in enhanced tooth mobility and immobilisation is not always necessary. Healing of a root fracture is only possible when the tooth is immobilized for a sufficiently long period. Regular control of tooth vitality is necessary since pulp necrosis can lead to an inflammatory reaction at the level of the fracture line.

Primary sensory trigeminal neurons supplying the dental pulp of incisors in guinea pigs were labelled by retrograde axonal transport. Using an autometallographic intensification procedure, 48 h after injection of wheat germ agglutinin/colloidal gold in the pulp, gold particles were detected in the cytoplasm of the neurons as black granulations. A morphometric study showed a bimodal repartition of the labelled neurons of the ganglion. By submitting ganglion slices to an anti-substance P immunserum revealed by immunocytochemistry, it could be observed that, among the neurons supplying the dental pulp of incisors, the majority of the largest were substance P immunopositive while the smallest were substance P immunonegative. These observations suggest that there could be at least two different populations of nerve fibres supplying the guinea pig incisor dental pulp. Substance P negative neurons could express different neurotransmitters.

Management of avulsed permanent teeth requires perfect knowledge of the different parameters influencing the short and mid-term and above all long-term prognosis. Based on a review of the literature and the analysis of 50 cases cared for in our unit enables us to propose, in accordance with the extra oral delay and the degree of dental maturation, a protocol for the different emergency situations. This clarification emphasizes the contribution of new preserving solutions which allow reimplantation delays up to 24 hours without effect on prognosis.

Tooth discoloration's may cause serious damage to the aesthetic appearance of the patients. These discoloration's can be treated in several ways but up to lately tooth structure had to be removed in an irreversible manner in order to provide sufficient bulk for the new restorative material. Nowadays thanks to the work of T. Croll and others a method has been established in a scientific way whereby tooth discoloration's confined to the outermost layer of enamel can be removed, through the application of an compound called PREMA which will simultaneous erode and abrade the enamel surface. If carefully selected the discoloration can be removed with only a limited loss of tooth structure. The authors describe the historical background of the method. Furthermore patient's selection, specific instruments and materials are described in detail. The clinical procedure is explained step by step, followed by a complete report of the effects of the procedure on the different tooth structures. Finally the long term results are discussed and the possibility to enhance the result by combining this method with home bleaching.

Blood, hairs and sperm are tissues currently used in forensic science to carry out DNA fingerprints in the field of individual identification. Our study aims at showing that dental pulp can also be an exploitable DNA source. A quantitative and qualitative DNA investigation on a yield gel with sizing extracted from this tissue shows that the molecule appears to be in a great quantity and of a high molecular weight. The last characteristic allows the use of the restriction fragments length polymorphic technique to make DNA fingerprints, based on the individual variations of the restriction sites disposition, within the DNA molecule, for a given enzyme. Thus, for an enzyme, the length of the restriction fragments obtained and revealed by a probe, is visualized by autoradiograph. According to this technique, we compared the DNA fingerprints obtained on 8 persons with the probe MS43A, from both pulpal and nucleated blood cells. During the extraction of the third molar of each sample, a small quantity of blood was taken in the tooth socket. In the same time DNA was recovered. For a same person, the autoradiograph showed the same pattern for both blood and tooth sample. The DNA profile similitude confirms the possibility of using the tooth for genetic analysis. The interest in using dental tissues as a DNA source of individual identification falls within the particular character of resistance of this organ towards physical or chemical exterior aggressions. The tooth which until now was used in Anthropology and Forensic Science for its morphological aspects could be used this way for genetic study.

Bleaching vital and non-vital has now become, for most dentists, a routine treatment. However the use of caustic products is not without risks. This article is a report of several publications that appeared in the endodontic literature cautioning the practitioner. Practical hints are given to reduce the side-effects for the patient.

The odontoblast responds to caries by the formation of sclerotic as well as reparative dentin. Sclerotic dentin is deposited during the early stages of the dentinal injury. It is characterized by the amplification of the collagen synthesis and the increase in alkaline phosphatase activity in the odontoblastic cell layer. Reparative dentin will be deposited under the sclerotic zone after the destruction of odontoblasts. At this stage, specific components from damaged dentinal tissues and/or odontoblastic necrotic debris will trigger pulpal cells to elaborate a cartilage-like matrix layer (fibrodentin). The latter may induce pulpal odontoblast-like cells to give rise to the tubular reparative dentin. Thus, pulpal cell response seems to be similar to bone-cell response to injury. Molecular signals responsible for this tissular healing remain largely unknown, but dentin is a potential source of matrical or soluble organic molecules that may be released after demineralization. Some of these factors have been identified in the sound tissue (glycoproteins, proteoglycans, growth factors, ...), but their role in the stimulation of the elaboration of the cicatricial tissue remains to be elucidated.

This in vitro study was designed to ascertain the cytotoxicity of two new dentin systems, Scotchbond MP (3M) and A.R.T. Bond (Coltène), on cultured cell monolayers prepared from fresh explants of human pulp tissue and placed in contact with the materials according to two methods. In a direct method, the two components (primer, adhesive) of each bonding system were placed directly on the cell layers. In an indirect method the bonding agents were placed on dentin slices of 0.3 and 1.0 mm thickness, that were interposed between agents and cells. After 8 days the cytotoxicity was quantitatively assessed by counting of the remaining living cells. The results indicate that the different primer solutions, when placed in direct contact with the cells, are more cytotoxic than the adhesive resins. In indirect contact through dentin, both bonding systems exhibited a similar cytotoxicity. The cytotoxicity appeared to be considerably diminished with a thick dentin slice interposed. These data confirm the role of dentin as a diffusion and buffer membrane for bonding materials. This kind of experiment could in the future improve the correlation between in vitro and in vivo results.