Expression of factors involved in dental pulp physiopathological processes by nemotic human pulpal fibroblasts.

AIM: To investigate in human dental pulp fibroblasts (HDPF) the expression of factors involved in dental pulp physiopathological processes and in an experimental model of cell activation called nemosis, and to compare the behaviour of pulp cell activation with sound lung fibroblast MRC5, employed as a reference model for nemosis. METHODOLOGY: Nemotic response was induced in three-dimensional cultures of HDPF and lung fibroblasts. The expressions of molecules involved in physiological (alkaline phosphatase, type I collagen) and in inflammatory processes (IL-6, CXCL8, CCL20, COX-2) were studied using real-time PCR. Concentrations of IL-6 and CXCL8 were analysed during 4 days with ELISA. Nonparametric tests were used to determine statistical differences between groups. RESULTS: A significant decrease (P < 0.001) in type I collagen and alkaline phosphatase was observed in MRC5 and HDPF nemotic responses. Although the amounts of mRNA differed between these cell types, there was an increase in CCL20, CXCL8 and COX-2 expression (P < 0.001). Unlike HDPF, MRC5 spheroids displayed significant amounts of IL-6 concentrations and mRNA expression. Notably, increased concentrations of CXCL8 were recorded in all three-dimensional cultures compared with monolayers as a function of time (P < 0.05). CONCLUSION: Although the nemotic responses observed were not identical in the pulpal and lung fibroblasts, similarities occurred in the expression of chemokines and cyclooxygenase-2. Nemotic reactions and inflammatory processes in pulp diseases share similarities in terms of the expression of factors. Thus, this in vitro model could constitute a powerful tool to study intercellular relations within the dental pulp and to develop new local treatments to counteract the inflammatory reaction that occurs during pulpitis.

Characterization of a programmed necrosis process in 3-dimensional cultures of dental pulp fibroblasts.

AIM: To analyse and compare the expression of necrosis markers in human lung and dental pulp fibroblasts and to determine whether this process differs by the type of mesenchymal cell. METHODS: Human dental pulp fibroblasts were obtained from unerupted third molars. Sound lung and pulpal fibroblasts were cultured in vitro as spheroids to determine the expression of the necrosis hallmark cyclooxygenase-2 (COX-2) mRNA using RT-PCR and the concentrations of vascular endothelial growth factor (VEGF) and hepatocyte growth factor/scatter factor (HGF/SF) proteins using an ELISA test. Cell viability within spheroids was also compared with spheroid diameters over time. RESULTS: Increased expression of COX-2 and VEGF was found in all spheroids compared with corresponding monolayers. Although HGF/SF was highly expressed in MRC5 cells, dental pulp fibroblasts aggregates maintained only a basal level compared with monolayer cultures. Further, the observed progressive loss of viable cells explained the decreased diameters of spheroids over time. The results demonstrate that necrosis occurs in sound lung and pulpal fibroblasts. This cell death also displays differences between these two different cell types, as they do not produce the same growth factors quantity release. CONCLUSIONS: The necrosis process occurred in human dental pulp fibroblasts and is different between the two cell types studied. This in vitro experimental necrosis model could become an interesting inflammatory tool. More investigations are needed to compare necrosis process in dental pulp fibroblast and inflammation during pulpitis.

Should pulp chamber pulpotomy be seen as a permanent treatment? Some preliminary thoughts.

AIM: To investigate the benefits of pulpotomy (to the level of the floor of the pulp chamber) as an endodontic treatment for teeth with vital pulps. METHODOLOGY: Seventeen patients, aged 7-54 years (mean of 37.2 year), were treated by pulpotomy and filling with ProRoot MTA(®) in premolar or molar teeth with vital pulps and without clinical evidence of irreversible pulpitis. The patients were then followed up for 12 to 24 months and the teeth then assessed by clinical and radiographic examination. Statistical analysis was performed with Kaplan-Meier survival probability statistics to estimate the survival of the treated teeth. RESULTS: At 24 months, the survival rate without any complementary treatment was estimated to be 82%. Two of the 17 treated teeth required root canal treatment for pain control and one for prosthetic reasons. CONCLUSIONS: Under the conditions of this study, pulpotomy offered a viable alternative to root canal treatment for teeth with vital pulps in the short term. However, there is insufficient clinical evidence to consider this technique for the treatment of every permanent tooth. Nevertheless, it should be considered as a potential alternative approach to be further developed for future applications.

[Communication in the patient care team about palliative situations' results of a survey at the Laennec Hospital, Paris]. / La communication dans les équipes de soins en situation palliative; résultat d'une enquête réalisée à l'hôpital Laënnec de Paris.

The authors report results from a sample survey in a university hospital in connection with the aspects of communication in medical team about paliative situations. The questionnaire, made from a paliative care group, consults the usual practices and during crisis just as patient is dying, in a curative medical care. Hospital is not a place to die. Difficulty in survey are probably in keeping with individual and collective defences opposite to dying patient.