Establishment and Evaluation of A Rat Model of Halitosis Caused by Imbalance of Oral Flora

doi:10.13701/j.cnki.kqyxyj.2023.08.015

Abstract

Abstract: Objective: To construct a rat halitosis model using salivary holistic microbiota colonization in patients with intra-oral halitosis (IOH), and to evaluate the feasibility of the model by detecting the changes of oral-associated microorganisms, associated metabolism, and breath values in rats. Methods: The healthy 6-8 week-old male Wistar rats were randomly divided into two groups, the model group (Group H) and the control group (Group C). Oral flora sampling was performed and breath values were measured under anesthesia after 1 week of acclimatization, mechanical cleaning of the teeth and mucosa of both groups of rats using cotton swabs dipped in saline. The cleaning was repeated and the oral mucosa and tooth were rinsed with 0.1% NaoCl for 5 min after 1 week of routine feeding, followed by a 10 min rinse with 23 μM buffered sodium ascorbate. Tooth and oral mucosa of rats in group H were coated using salivary holistic microbiota of IOH patients added with protective solution once daily, with water and food fasting for 1 h after application, followed by continuous administration of 10% high sugar water, and oral flora sampling under anesthesia for 6 weeks. Group C was also routinely reared and sampled. The 16SrRNA sequencing technique was used to detect microbial changes in the rat oral cavity, the PICRUSt was used to predict the metabolic function of the flora, and the Halimeter breath detector was used to test the breath values of the rats every 2 weeks. Results: Compared with group C, the proportion of IOH-associated species such as porphyromonas, fusobacterium, gemella, leptotrichia, and peptostreptococcus in the oral flora of group H was significantly higher. PICRUSt metabolic prediction analysis showed that the metabolic pathways associated with halitosis were significantly enhanced in group H compared with group C. There was also a significant increase in breath test values. Conclusion: This modeling method allows IOH-related microorganisms to colonize the oral cavity of rats and exert their odor-producing function and well simulates the oral flora and breath characteristics of clinical patients, and can be used in future research on new treatment modalities and disease development of IOH.

Key words: intra-oral halitosis, oral flora, animal models

HUANG Zhiqiang, CHENG Yongbo. Establishment and Evaluation of A Rat Model of Halitosis Caused by Imbalance of Oral Flora[J]. Journal of Oral Science Research, 2023, 39(8): 745-750.

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