Protective effect of a new biomaterial against the development of experimental osteoarthritis lesions in rabbit: a pilot study evaluating the intra-articular injection of alginate-chitosan beads dispersed in an hydrogel.

OBJECTIVE: This study aimed to evaluate the structural benefit of a new biomaterial composed of alginate-chitosan (AC) beads dispersed in a hydrogel (H) derived from chitosan on the development of osteoarthritis (OA) in rabbit. DESIGN: OA was induced by the surgical transection of the anterior cruciate ligament in rabbits. Animals received a single intra-articular injection (900 µl) of AC beads in H hydrogel, H hydrogel alone or saline a week after surgery. OA development was followed by X-rays. Blood samples were collected throughout the study to measure biological markers (Prostaglandins E2 - PGE2 and C reactive protein - CRP). Macroscopic observation and histological evaluation of articular cartilage and synovial membrane were performed 6 weeks after surgery. RESULTS: AC beads in H hydrogel prevented from the development of OA based on the reduction of the Kellgren & Lawrence (K&L) score. It also significantly reduced the histological score of cartilage lesion severity. This effect was homogenous on every joint compartment. It was due to a significant effect on cartilage structure and cellularity scores. The injection of AC beads in H hydrogel also tended to reduce the synovial membrane inflammation. No significant variation of biological markers was noted. CONCLUSIONS: The present pilot study provides interesting and promising results for the use of AC beads in H hydrogel in animal. It indeed prevented the development of OA cartilage lesions without inflammatory signs. The potencies of this biomaterial to protect OA joint should be further documented. It could then represent a new alternative for viscosupplementation in human OA management.

Combined benign odontogenic tumors: CT and MR findings and histomorphologic evaluation.

SUMMARY: Calcifying epithelial odontogenic tumors and calcifying odontogenic cysts are rare, benign odontogenic tumors. We report two cases of an exceptional combination of these tumors with either an ameloblastic fibroodontoma or an odontoma.

[Lesions of the inferior alveolar nerve during extraction of the wisdom teeth. Consequences--prevention]. / Lésions du nerf alvéolaire inférieur au cours de l'extraction des dents de sagesse. Conséquences--prévention.

Neurological consequences of extractions of the third inferior molar can be severe. Progress in imaging techniques has made it possible to identify molars << at risk >>. Extraction by wear without removal of the apex is proposed as a means of avoiding damage to the alveolar nerve. If no surgical prophylaxy is used the risk is major sequellae: painful anaesthesia of the area involved. There is no really effective treatment for such sequellae, creating persistent psychological problems throughout life.

[Mandibular osseous lacuna, salivary inclusion]. / Lacune osseuse mandibulaire, inclusion salivaire.

Salivary inclusion is seen, on panoramic films of the maxilla and the mandible, in the form of a mandibular osseous lacuna. Such an indicative diagnostic image, the prognosis for which is often sobering, requires CT scan exploration. The latter permits the diagnosis of Stafne's lacuna, the nature of which is benign. Quick and sure.