Mesenchymal stem cells (MSC) are involved in the regeneration of various missing or compromised periodontal tissues, including bone. MSC-derived conditioned medium (CM) has recently been explored as a favorable surrogate for stem cell therapy, as it is capable of producing comparable therapeutic effects. This study aimed to evaluate the influence of periodontal ligament stem cells (PDLSC)-CM on osteoblasts (OB) and its potential as a therapeutic tool for periodontal regeneration. Human PDLSC were isolated and characterized, and CM from these cells was collected. The presence of exosomes in the culture supernatant was observed by immunofluorescence and by transmission electron microscopy. CM was added to a cultured osteoblastic cell line (Saos-2 cells) and viability (MTT assay) and gene expression analysis (real-time PCR) were examined. A cell line derived from the periodontal ligament and showing all the characteristics of MSC was successfully isolated and characterized. The addition of PDLSC-CM to Saos-2 cells led to an enhancement of their proliferation and an increased expression of some osteoblastic differentiation markers, but this differentiation was not complete. Saos-2 cells were involved in the initial inflammation process by releasing IL-6 and activating COX2. The effects of PDLSC-CM on Saos-2 appear to arise from a cumulative effect of different effective components rather than a few factors present at high levels.

The objective of the present work was to develop a three-dimensional culture model to evaluate, in a short period of time, cartilage tissue engineering protocols. The spheroids were compared with the gold standard pellet culture. The dental mesenchymal stem cell lines were from pulp and periodontal ligament. The evaluation used RT-qPCR and Alcian Blue staining of the cartilage matrix. This study showed that the spheroid model allowed for obtaining greater fluctuations of the chondrogenesis markers than for the pellet one. The two cell lines, although originating from the same organ, led to different biological responses. Finally, biological changes were detectable for short periods of time. In summary, this work demonstrated that the spheroid model is a valuable tool for studying chondrogenesis and the mechanisms of osteoarthritis, and evaluating cartilage tissue engineering protocols.

Purpose: Several studies have demonstrated the role of periodontal disease as risk factor of adverse pregnancy outcomes, including preterm birth, low birthweight and pre-eclampsia. As such, midwives can play an essential role in prevention and early screening as the preferred intermediary of pregnant women. The purpose of this study was to assess the knowledge, training and daily practice habits of midwives to determine if they fulfill their role in oral health prevention.Materials and Methods: A questionnaire was sent by e-mail to practicing midwives and fifth-year midwifery stu-dents in the Brittany region of France. Data were collected online and descriptive data analyses were conducted.Results: A total of 192 practicing midwives and 13 students participated in the survey. The results showed that the majority of midwives were not familiar with the correlation between periodontal disease and adverse pregnancy outcomes and did not implement screening and prevention to a sufficient extent. Conclusion: The explanation for this lack of knowledge seems to come from the initial training, since the topic of oral health is almost never discussed during midwives' studies. Most agreed they needed more training on peri-odontal disease and adverse pregnancy outcomes. Improving and integrating oral health education into the midwife academic curriculum can enhance midwives' engagement in oral health.

L’ingénierie tissulaire constitue une approche prometteuse pour la reconstruction des tissus parodontaux. Dans ce domaine, les cellules souches mésenchymateuses (CSM) sont particulièrement attrayantes du fait de leurs caractéristiques uniques et de leur rôle majeur dans la réparation osseuse. Des CSM d’origine pulpaire et ligamentaire ont été obtenues à partir d’explants dentaires et caractérisées par cytométrie en flux et tests fonctionnels. Le modèle des sphéroïdes a été utilisé pour évaluer le comportement des CSM en 3D. Les milieux conditionnés de CSM ligamentaires, contenant leur sécrétome, ont été recueillis et leurs effets sur la différenciation ostéoblastique étudiés. L’association d’un verre bioactif (46S6) au Vanadium a été évaluée pour un futur protocole d’ingénierie tissulaire. Les caractérisations phénotypique et fonctionnelle ont permis d’objectiver la présence de CSM dans le ligament alvéolo-dentaire et dans la pulpe dentaire. La culture sous forme de sphéroïdes a permis de potentialiser la différenciation des CSM, avec cependant une diminution des diamètres des sphéroïdes et une chute du nombre de cellules constitutives. Les milieux conditonnés de CSM ligamentaires ont eu un effet, en particulier via les exosomes, sur des cellules de lignées ostéoblastiques. Le 46S6 s’est avéré de forte biocompatibilité avec les CSM, bien que l’ajout de Vanadium n’ait pas eu l’effet escompté.