NKOLO TOLO FD1*, NKECK JR2, ATANWO DONGMO LN1, EKO M3, TANETCHOP MAGOUO N1, OBONO EKAMENA MJ1, NJIKI BIKOI JAKY4
1Department of Oral Surgery, Faculty of Medicine and Biomedical Sciences of the University of Yaounde I
2Department of Internal Medicine, Faculty of Medicine and Biomedical Sciences, University of Yaounde I
3Department of Biochemistry, Faculty of Medicine and Biomedical Sciences, University of Yaounde I
4Department of Microbiology, Faculty of Science, University of Yaounde I
*Corresponding author: nkolo.tolo@fmsb-uy1.cm, +237694144681
Received: 20 April 2025, Reviewed: 09 July 2025, Revised: 10 July 2025, Accepted: 19 July 2025, Published: 06 August 2025Â
https://doi.org/10.63342/cjbbs2025.33.017.eng
ABSTRACT
A detailed understanding of the kinetics of mandibular bone consolidation requires robust experimental models. This study assesses the robustness and reproducibility of a Wistar rat model of mandibular bone lesions. The study was conducted on 24 Wistar rats, divided into three experimental groups of 08 rats. The first group served as control. The second group underwent extraction of the lower central incisor with injury to the underlying alveolar bone. The third group underwent drill holes in the mandibular symphysis. The rats were sedated by intraperitoneal injection of ketamine and diazepam. Tooth extraction was performed with an incisor forceps, and drill holes with a micromotor and steel drill, under saline irrigation. All animals received post-operative antibiotic and analgesic treatment. Alkaline phosphatase (ALP) activity was significantly increased in females (289.33 to 437 IU/L, p<0.01) and males (56.75 to 303.67 IU/L, p<0.01), indicating a more intense and prolonged osteogenic response with drilling than with tooth extraction. In females, the drill hole significantly decreased calcium to 55.5 mg/L (p<0.05), whereas in males, tooth extraction significantly increased it to 24.3 mg/L (p<0.05) and drilling to 128.25 mg/L (p<0.05), suggesting a variable bone remodeling response according to sex and lesion type. In females, phosphorus increased significantly from week 1 in the drill hole group (p<0.05), reaching a mean value of around 100 mg/L, while in males, the progressive increase in phosphorus in the same group occurred between weeks 2 and 6 (p<0.05), reaching a peak of around 120 mg/L at week 6. The results obtained, in particular the kinetics of biochemical markers, confirmed the relevance of this model for assessing the mechanisms of bone consolidation. The prospects for future research are vast and promising, paving the way for significant advances in maxillofacial surgery and regenerative medicine.
Keywords: Bone Remodeling, Robustness, Reproducibility, Mouse Model, Mandibular Fracture
RÉSUMÉ
La comprĂ©hension fine de la cinĂ©tique de la consolidation osseuse mandibulaire nĂ©cessite des modèles expĂ©rimentaux robustes. Ce travail Ă©value la robustesse et la reproductibilitĂ© d’un modèle de lĂ©sions osseuses mandibulaires chez le rat Wistar. L’Ă©tude a Ă©tĂ© menĂ©e sur 24 rats Wistar, divisĂ©s en trois groupes expĂ©rimentaux de 08 rats. Le premier groupe a servi de contrĂ´le. Le deuxième groupe a subi une extraction de l’incisive centrale infĂ©rieure avec lĂ©sion de l’os alvĂ©olaire sous-jacent. Le troisième groupe a subi des trous de forage au niveau de la symphyse mandibulaire. La sĂ©dation des rats a Ă©tĂ© rĂ©alisĂ©e par injection intra-pĂ©ritonĂ©ale de kĂ©tamine et de diazĂ©pam. L’extraction dentaire a Ă©tĂ© effectuĂ©e avec un davier incisif, et les trous de forage avec un micromoteur et un foret en acier, sous irrigation de sĂ©rum physiologique. Tous les animaux ont reçu un traitement antibiotique et analgĂ©sique post-opĂ©ratoire. L’activitĂ© de la phosphatase alcaline (PAL) a significativement augmentĂ© chez les femelles (289,33 Ă 437 UI/L, p<0,01) et chez les mâles (56,75 Ă 303,67 UI/L, p<0,01), indiquant une rĂ©ponse ostĂ©ogĂ©nique plus intense et prolongĂ©e avec le trou de forage qu’avec l’extraction dentaire. Chez les femelles, le trou de forage a diminuĂ© le calcium Ă 55,5 mg/L, tandis que chez les mâles, l’extraction dentaire l’a augmentĂ© Ă 24,3 mg/L et le forage Ă 128,25 mg/L, suggĂ©rant une rĂ©ponse de remodelage osseux variable selon le sexe et le type de lĂ©sion. Chez les femelles, le phosphore a significativement augmentĂ© dès la première semaine dans le groupe trou de forage, atteignant une valeur moyenne d’environ 100 mg/L, tandis que chez les mâles, l’augmentation progressive du phosphore dans le mĂŞme groupe s’est produite entre la 2ème et la 6ème semaine, atteignant un pic d’environ 120 mg/L Ă la 6ème semaine. Les rĂ©sultats obtenus, notamment la cinĂ©tique des marqueurs biochimiques, ont confirmĂ© la pertinence de ce modèle pour Ă©valuer les mĂ©canismes de consolidation osseuse. Les perspectives de recherche future sont vastes et prometteuses, ouvrant la voie Ă des avancĂ©es significatives dans le domaine de la chirurgie maxillo-faciale et de la mĂ©decine rĂ©gĂ©nĂ©rative.
Mots clés : Remodelage Osseux, Robustesse, Reproductibilité, Modèle Murin, Fracture Mandibulaire.
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