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Endodontic flora is dominated in the apical part of the channels by strict anaerobic and some facultative anaerobic bacteria but also by Candida yeasts, especially Candida albicans species that are involved in the maintenance and persistence of endodontic infections. Their elimination of the canal system in practice by chemo-mechanical methods of disinfection is not always guaranteed. Thus, this in vitro study was performed to determine the sensitivity of C. albicans with sodium hypochlorite (NaOCl) dosed at 2.5 %, the chlorhexidine digluconate 0.5 % and calcium hydroxide used in inter-session medication.The diffusion method was used initially to test the sensitivity of C. albicans strains with the above products. Then a dilution technique has allowed us to determine the minimum inhibitory concentration of these active products on C. albicans.Strains from infected pulp teeth of patients showed a sensitivity of C. albicans to sodium hypochlorite to a minimum inhibitory concentration less than 70μg/mL and 30μg/mL for chlorhexidine.This study demonstrated a sensitivity of C. albicans to sodium hypochlorite and chlorhexidine.

Direct pulp capping allows, in the event of pulpal exposure, to preserve the vitality of the pulp with its dentinogenic potential. Since its first use in 1920 by Hermann, calcium hydroxide was considered as "Gold Standard" for pulp capping. However, since 1998, the Mineral Trioxide Aggregate (MTA) appeared on the market. Its use as a material of direct pulp capping showed excellent results. Since 2010, a new bioactive cement is available for our treatments: Biodentine®. This product seems to be interesting and promising thanks to its physicochemical and biological properties. Studies are awaited in order to determine the contribution of this product, compared to the two others, for the preservation of pulpal vitality. We present a study carried out in the department of Odontology of the hospital of Brest. This study has assessed the short-term outcome of direct pulp cappings using calcium hydroxide, MTA and Biodentine®, as well as the factors having influenced the success rate.; Le coiffage pulpaire direct permet, en cas d'exposition pulpaire, de conserver la pulpe vivante avec son potentiel dentinogénique. Depuis sa première utilisation en 1920 par Hermann, l'hydroxyde de calcium a été considéré comme le "Gold Standard" en matière de coiffage pulpaire. Cependant, depuis 1998, le Mineral Trioxide Aggregate (MTA) est apparu sur le marché. Son utilisation comme matériau de coiffage pulpaire direct a montré d'excellents résultats. Désormais, depuis 2010, un nouveau ciment bioactif est disponible dans notre arsenal thérapeutique : le Biodentine®. Ses propriétés physico-chimiques et biologiques en font un produit intéressant et prometteur. Des études sont attendues afin de déterminer la contribution de ce produit par rapport aux deux précédents pour le maintien de la vitalité pulpaire. Nous présentons une étude réalisée dans le service d'Odontologie du Centre Hospitalier Universitaire de Brest, évaluant le devenir à court-terme de coiffages pulpaires directs réalisés à l'aide d'hydroxyde de calcium, de MTA et de Biodentine®, ainsi que les facteurs ayant influencé le taux de succès.

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.

The aim of this study was to compare hydroxyl ions diffusion from various calcium hydroxide forms: Hycal (1), Roeko points (2) and aqueous suspension placed in the pulpar chamber (3) or in the root canal (4). These experiments were conducted with bovine incisors in order to obtain quantitative evaluation. 540 lateral cavities, deep and superficial, were created in root dentin to measure the hydroxyl ions diffusion with a color indicator, the Blue epsilon With Hycal and aqueous suspension the diffusion of the OH- is obtained in the superficial cavities situated in the coronal part at 14 days (1 = 72%; 3 = 44%; 4 = 100%, (n=18)). In the apical part of the canal this phenomenon is never complete at 21 days (1 = 17%; 3 = 22%; 4 = 17%, (n=18)). No diffusion was observed with the Roeko points (the first generation).

Calcium hydroxide has found its use in endodontic treatments. On the other hand, chlorhexidine is more and more proposedfor uses in clinical endodontics. Could chlorhexidine surpass calcium hydroxide and what are the benefits of chlorhexidine? This literature overview concludes that both medications are useful and that further studies are necessary before chosing one above the other.

On non-vital deciduous molars, inter-radicular bone resorption is often an indication of extraction. The endodontic treatment of these teeth by means of zinc oxide-eugenol (ZOE) paste also showed its limits. To mitigate the deficiencies of this material, we suggested a preliminary treatment by means of calcium hydroxide (Ca(OH)2) for its anti-inflammatory and antiseptic properties as well as its ability to stimulate calcified tissues apposition or remineralisation. This study concerns 21 non-vital deciduous molars. X-rays excluded any lesion of the underlying permanent bony crypt (bone tissue) as well as any inflammation of the dental follicle. After preparation, root canals were filled by means of Pulpdent. An initial X-ray check was made 15 days and then every 3 months. After disappearance of the inflammatory resorption, root canal fillings were performed with ZOE paste. The remineralisation of the inter-radicular alveolar bone was observed for 14 deciduous molars, which were then filled using ZOE. The remineralisation period varies from 3 to 18 months depending on the scale of the lesion. Of the 7 failed treatments, 3 failed following downfall of the crown filling material, and 2 due to failure to keep appointments and late replacement of resorbed Ca(OH)2. On 2 teeth, the treatment did not stop the lesion forming. Calcium hydroxide (Ca(OH)2) give encouraging results in the treatment of inter-radicular alveolar bone resorption of non-vital deciduous tooth. Its fast resorption requires rigorous controls, frequent refills, and thus strong motivation on the part of the child and parents. It cannot, on any account, be considered as permanent filling material.

The aim of the present study is to propose a classification of calcium hydroxide pastes on the basis of the vehicle that retains the calcium hydroxide. The vehicle determines the working characteristics of the calcium hydroxide: viscous and only vehicles prolong the action of the calcium hydroxide as compared with water-soluble substances. Physicochemical properties of the vehicle may limit the effectiveness in disinfecting the entire root canal system. As calcium hydroxide is not effective against all bacterial species found in root canal infections, associations with other medicaments have been proposed to enhance the efficacy of the intracanal medication.

Calcium hydroxide is a widely used material in endodontic treatment due to its high alkalinity and antimicrobial properties. It is thought to create a favourable environment for periradicular repair and healing, and to stimulate hard tissue formation. The aim of the present retrospective study was to evaluate the effect of accidental and voluminous overextensions of calcium hydroxide pastes into periapical lesions and tissues on the prognosis of periapical healing. It was seen that calcium hydroxide overextensions did not disfavour healing, none of the endodontic treatments failed but healing was delayed in the majority of cases and in a number of cases extrusion induced immediate flare-ups. Therefore the deliberate extrusion of calcium hydroxide into periapical tissues is not advocated.

The calcium hydroxide used as intracanalar temporary medication in modern endodontics, is the aim of this clinical and radiographic appraisal of endodontic treatment during two sessions (HESS J. C. and all. 1990); on 22 mature permanent teeth with peri apical lesion. In this second Dakar serial study, the mediate disinfection during 6 weeks in average, was followed by a root canal filling for: 11 mono-radicular teeth by compactage of gutta percha, adjusted monocone for 11 pluri-radicular teeth; and so by definitive coronal restoration. The direct magistral preparations used in this study are not expensive, but simple and efficient; our endodontic processing (pre-treatment and treatment) end up at clinical silence and radiographic apical healing in 90.91% of cases after 9 months for 66.67% of root canal filling located at the safety apical limit.

Root resorption can be divided into two main categories: internal root resorption and external root resorption. Internal root resorption is a pathology that can lead to tooth destruction in the short term and must consequently be stopped as soon as possible by applying adequate canal treatment. Until now, despite many research studies, very little is known about its causes and the way this kind of resorption appears. There are many different forms of external root resorption and it has a very diverse etiology. An external root resorption can thus appear in case of orthodontic treatment or due to the pressure brought by cysts, tumours or impacted teeth. A trauma or an infection may also lead to the development of an external root resorption. Because they are so diverse, each of these forms of external root resorption requires a specific treatment. It should also be noted that internal root resorptions, and some forms of external resorption too, often respond favourably to a calcium hydroxide treatment.

Medication can never disinfect a badly shaped canal and successful treatment will depend on the endocanal preparation. Despite the indisputable antibacterial efficacy of Rocklès 4 in vitro, use of this medicament should be banned because of its toxicity, its mutagenic and antigenic action and its long-term inefficacy in vivo. The same goes for all other antiseptics, anti-inflammatory agents and antibiotics mentioned, that should be discarded because of their harmful effects on patients or their inefficacy on endodontic flora. Our endodontic medicine cabinet should only contain the following products: irrigation agent: NaOCl 2.5% medication in 2 sessions: calcium hydroxide prescription or 'Réogan rapide'.

Calcium hydroxide is one of the most often medication used for temporary treatment in endodontics. Different forms of preparation are available. The aim of this study is to evaluate in vitro the elimination of the pharmaceutical and the commercial forms of presentation. The aspect of the dentinal walls were analysed using SEM and X-ray microanalysis. The results show that Ca(OH)2 removal is difficult but there is no significant difference of elimination between the two forms.

This study was designed to complete the cell culture test for the cytotoxicity assessment of dental material presented by Christen et al. (1989) and Regad et al. (1989). Two liner materials were selected for this experiment which had already been subjected to both in vivo and in vitro tests. After 2, 7 and 14 days of contact with the test materials, the cell responses were evaluated under the light microscope by their growth pattern and morphological aspects. Cell synthesis of fibronectin and type I and III collagen was studied by immunofluorescence. Surface appearance of the cells in contact with the materials as well as their structures were observed by scanning electron microscopy. This study confirmed the viability of the in vitro cytotoxicity assessment methods with cell cultures. The results also demonstrated the potentials of this method in the early screening of dental materials for their biological compatibility.

The purpose of this in vitro study was to evaluate the sensibility of frozen human pulp cells, in order to examine the cytotoxicity of dental products. The cell cultures and the biological assessments, using still incomplete human premolars and pulp germs, were achieved according to a standardized method. The sensibility of frozen cells was assessed by comparison of cell reactions before and after 1, 3 and 6 months of congelation, for two dental products called Aquacem and Pulpdent, the cytotoxicity and biocompatibility of which were further confirmed. The behaviour of cells with and without congelation was microscopically evaluated, the growth and morphology of cells were assessed after 7, 14, 21 and 28 days. The comparison of the results showed a similar behaviour between cells with and without congelation, except for few cell alterations in the form of granula which occurred during a short period, probably due to the congelation process. This cell liability offers the opportunity to elaborate a bank of cells available on demand for preliminary cytotoxicity assessments.

Stimulation on exposed dentine at the enamo-dentinal junction is often painful and uncomfortable for the affected patient. Two hundred and forty-four subjects suffering from dentinal sensitivity, aged from 18 to 48 years old, were treated with two types of desensitizing agent. In this study, we used sodium fluoride (Duraflor) and calcium hydroxide (Dycal catalyst). The desensitizing agent is first applied on the exposed dentine and then burnished, without local anaesthesia, until all sensitivity has disappeared. After the first session, 100% of the subjects were desensitized. All subjects were seen 1, 2, 3, 6, 13 and 26 weeks after the first application. After 6 months, 94% of the subjects treated with calcium hydroxide (Dycal) and 87% of those treated with sodium fluoride (Duraflor) were still desensitized. This difference is statistically significant at alpha = 0.01 (Anova test). In conclusion, our study reveals that both calcium hydroxide (Dycal) and sodium fluoride (Duraflor) are effective in the treatment of dentinal hypersensitivity. A slight significant advantage in using calcium hydroxide is also noted.

With the use of calcium hydroxide, apexification and apexogenesis will result in the formation of an apical barrier (osteo-cementum or similar hard tissue) or in the apical closure of the traumatised tooth, in order to realise later on, a hermetic and permanent root canal obturation.

To assess the efficiency of a calcium hydroxide containing root canal sealer (Sealapex), 227 obturated canals were examined clinically and radiologically after one year. When compared to a previously published study (VerdonHolz 1988), the results show a decline of radiopacity within the canals and an almost complete resorption of the cement overfillings. It was also noted a slight improvement in the radiologic appearance of the periapical lesions.

The radiologic studies of 200 consecutive AIDS patients with neurologic symptoms were evaluated to determine their diagnostic specificity and prognostic value. Of 81 patients with initially normal CT scans, four (5%) later developed progressive neurologic illness. Of 75 patients with CT evidence of diffuse cerebral atrophy, 12 (16%) later developed CT abnormalities or had postmortem CNS disease. CT scans showed mass lesions initially in 44 patients and later in an additional seven patients. Although toxoplasma gondii infection was the most frequent cause of these lesions, the CT characteristics of cerebral toxoplasmosis are too nonspecific to warrant diagnosis without biopsy. Preliminary evidence suggests that MRI may be more sensitive than CT in detecting intracranial disease in patients with AIDS.

Increasing emphasis is being placed on the use of agents for protection of the pulp and the deep regions of the pulp cavity, modern conservative dentistry attempting as far as possible to conserve pulp vitality. The aim of this report is to assist the dental practitioner in his choice of the different varnishes and cements marketed by dental product manufacturers, to ensure the maximum of benefits for patients' teeth.