Attitudes of dentists regarding the restoration of root canal treated teeth: a survey in Greece.

OBJECTIVES: To investigate attitudes of Greek dentists regarding the restoration of root canal treated (RCT) teeth and to compare them to recommended guidelines. Additionally, to examine relationships between degree of dentists' professional experience or region of practice location and attitudes of restoring RCT teeth. METHOD: Data were collected from 302 dentists using a structured self-administered questionnaire. For each dentist a score was assigned reflecting the level of compliance with scientific recommendations for restoration of RCT teeth. RESULTS: 89.4% of the respondents reported that not every RCT tooth requires a post while the 46.4% stated that a post reinforces it. 76.2% of the participants believed that the ferrule design provides a reinforcement to RCT teeth. Dentists with 6-20 years of experience showed a higher level of compliance with the principles in the literature than their colleagues with less or more years of practising. No significant difference was detected between dentists practising in urban and rural areas. CONCLUSIONS: The majority of Greek dentists had knowledge in accordance with recommended guidelines, except the aspect of the reinforcement effect by the post. In contrast to the region of practice location, the degree of professional experience influenced the restoration of root-treated teeth.

Dental pulp stem cells' secretome enhances pulp repair processes and compensates TEGDMA-induced cytotoxicity.

OBJECTIVES: Aim of this study was to investigate the effects of dental pulp stem cells' (DPSCs) secretome, expressed through their culture conditioned medium (CM), on biological endpoints related to pulp repair and on TEGDMA-induced cytotoxicity. METHODS: DPSCs cultures were established and characterized for stem cell markers with flow cytometry. CM was collected from DPSCs under serum deprivation conditions (SDC) and normal serum conditions (NSC) at various time-points. CM effects on DPSCs viability, migration and mineralization potential were evaluated by MTT assay, transwell insert and in vitro scratch assay and Alizarin Red staining/quantification respectively. TEGDMA (0.25-2.0mM) cytotoxicity regarding the same biological endpoints was tested in the presence/absence of CM. TGF-ß1 and FGF-2 secretion in CM was measured by ELISA. RESULTS: CM collected under SDC (4d) was able to increase cell viability by 20-25% and to reduce TEGDMA cytotoxicity by 20% (p<0.05). CM positive effects were not obvious when collected under NSC. Transwell assay showed significant increase (26%, p<0.05) of DPSCs' migration after CM exposure, whereas both migration assays could not support a migration rate improvement in TEGDMA-treated cultures exposed to CM compared to TEGDMA alone. CM significantly (p<0.01) increased DPSCs mineralization potential and completely counteracted TEGDMA cytotoxicity on this process. ELISA analysis showed a time-dependent increase of TGF-ß1 and a TEGDMA concentration-dependent increase of both TGF-ß1 and FGF-2 in CM. SIGNIFICANCE: These findings suggest that DPSCs secretome increases their viability, migration and mineralization potential and counteracts TEGDMA-induced cytotoxicy, revealing a novel mechanism of DPSCs autocrine signaling on pulp repair processes.