using a mouth gag for pulpitis assessment in mice

Création d’un modèle murin d’inflammation de la pulpe à l’aide d’un nouveau bâillon buccal 

The dental pulp, an integral part of the tooth, is responsible for multiple essential functions such as nutrient supply, dentin formation, sensory function, and defense reactions1. Nevertheless, the dental pulp, surrounded by hard tissue, is susceptible to injuries and damages from deep caries, pulpitis, trauma, or subsequent therapies2,3. The absence of functional dental pulp increases the risk of tooth fragility4. Moreover, the loss of pulp vitality in young permanent teeth can adversely affect tooth maturation, and current denture techniques fail to restore the neural feedback offered by healthy pulp4. This situation has led researchers to explore alternative solutions for managing inflamed pulp beyond mere removal.
In 2007, Murray et al. initiated the application of tissue engineering in regenerative endodontics, thereby sparking increased interest in pulp preservation and regeneration5. However, inflamed pulp tissue poses a challenge as cells release inflammatory factors such as IL-6, which recruit inflammatory cells and results in cell necrosis, loss of pulp vitality, and complications in functional recovery6,7. Understanding inflammation and the associated cell death is, therefore, crucial for advancements in the preservation of vital pulp. There are a number of experiments that have been conducted to explore the molecular biology of the inflame pulp in vivo or in vitro8,9. Though in vitro&#160;experiments like 2D or 3D cell cultures have been developed for years and are becoming mature and widely used to test reactions of pulp cells to inflammatory factors, these experiments cannot reflect the interaction between pulp tissue and the systemic immune system10. If the phenomenon being studied is derived from cells of other tissue origin like immune, vascular and nervous system, then pure pulp cell culture will lead to a dead end. Therefore, in vivo experiments are very necessary and referential.
Mice have increasingly become a common choice in inflammation research in vivo&#160;due to their cost-effectiveness, high fertility, and vitality. However, a comprehensive protocol for mice pulpitis model is currently absent, which can serve as a reference. The small size of mice and their sensitivity to stimulation pose significant challenges during experimental procedures. Observing the minuscule teeth concealed deep within the mouse mouth often necessitates the use of a cantilever microscope, notwithstanding the more common presence of desktop microscopes in laboratories. The absence of a mouth opener requires assistance from others. To address this, the group has devised a mouth-gag using readily available materials which aims to provide a standardized and reproducible protocol for constructing the mice pulpitis model. This article details the procedure, covering preoperative preparation, immobilization, pulp exposure surgery, and sample collection on C57 mice. This protocol recommends the use of the mouth-gag, providing information on its structure, production, and application to facilitate other researchers in replicating the procedure.

Pleins feux sur l’auteur : Améliorer la recherche sur la pulpe dentaire grâce à des modèles murins améliorés

Etablissement d’un modèle d’exposition à la pulpe murine avec un nouveau bâillon pour la recherche sur la pulpite

Individual experiments like 2D or 3D cell cultures have been widely used to test the reactions of dental pulp cells. These experiments cannot reflect the interaction between pulp tissue and the systemic immune system. Therefore, in vivo experiments are becoming increasingly popular in endodontic research.C57 mice have increasingly become a common choice in inflammation research on dental pulp due to their cost effectiveness, high fertility and vitality. However, the small size of mice and lack of coordination posed significant challenges during experimental procedures. The fixation process is an important factor that higher the technical threshold.We devised a novel mouth gag using readily available materials and simple assemblies to assist researchers in pulp exposure surgery. According to our research, this mouth gag can significantly shorten the time required for beginners to immobilize the mouth and expose the maxillary first molar of mice.

Utilisation d’un bâillon buccal pour l’évaluation de la pulpite chez la souris

Pour commencer, fixez une souris anesthésiée en position couchée sur une plaque de fixation. Fixez les membres avec du ruban adhésif. Compressez les extrémités libres d’un bâillon buccal préparé avec le pouce et l’index.Fixez les incisives avant de la souris dans la rainure trapézoïdale entre les deux bras du bâillon buccal. Assurez-vous que le bras avec l’abaisse-langue est placé sur la mandibule. Vérifiez la première molaire maxillaire pour vous assurer qu’elle est exempte de caries dentaires, de traumatismes et d’odontogenèse.Évaluez la gencive environnante pour vous assurer de l’absence de rougeur, d’enflure ou de fistule. Ensuite, vérifiez la santé des dents opposées. Ensuite, à l’aide d’une fraise dentaire, percez le côté occlusal de la première molaire maxillaire à 20 000 tr/min.Retirez l’émail. À l’aide d’une seringue, déposez une solution saline normale toutes les trois minutes sur la dent pour éviter la surchauffe. Placez une lime C+ numéro 8 sur la position la plus basse de la fosse percée et percez la dernière dentine pour exposer la chambre pulpaire.Nettoyez les fragments autour de la dent, puis retirez le bâillon buccal. Le temps nécessaire pour réparer la bouche avec le bâillon buccal et pour trouver la première molaire maxillaire a été considérablement raccourci par rapport à la méthode traditionnelle. L’exposition de la pulpe a été confirmée par micro-tomodensitométrie et modélisation de reconstruction.24 heures après l’intervention, la majeure partie du tissu pulpaire a conservé sa morphologie.

Research

JoVE Journal

Medicine

Using A Mouth Gag for Pulpitis Assessment in Mice

Establishment of a Murine Pulp Exposure Model with a Novel Mouth-Gag for Pulpitis Research

Pulpitis, a common cause of natural tooth loss, leads to necrosis and loss of bioactivity in the inflamed dental pulp. Unraveling the mechanisms ...

Recherche

Médecine

Preparation of the Mouth Gag for a Mouse Pulpitis Model

Préparation du bâillon buccal pour un modèle de pulpite de souris