Investigating Oral Microbiome Profiles in Children with Cleft Lip and Palate for Prognosis of Alveolar Bone Grafting

Abstract

In this study, we sought to investigate the oral microbiota structure of children with cleft lip and palate (CLP) and explore the pre-operative oral bacterial composition related to the prognosis of alveolar bone grafting. In total, 28 patients (19 boys, 9 girls) with CLP who were scheduled to undergo alveolar bone grafting for the first time were recruited. According to the clinical examination of operative sites at the third month after the operation, the individuals were divided into a non-inflammation group (n = 15) and an inflammation group (n = 13). In all, 56 unstimulated saliva samples were collected before and after the operation. The v3-v4 hypervariable regions of the 16S rRNA gene were sequenced using an Illumina MiSeq sequencing platform. Based on the beta diversity of the operational taxonomic units (OTUs) in the inflammation and non-inflammation samples, the microbial variation in the oral cavity differed significantly between the two groups before and after the operation (P < 0.05). Analysis of the relative abundances of pre-operative OTUs revealed 26 OTUs with a relative abundance higher than 0.01%, reflecting a significant difference of the relative abundance between groups (P < 0.05). According to a principal component analysis of the pre-operative samples, the inflammation-related OTUs included Tannerella sp., Porphyromonas sp., Gemella sp., Moraxella sp., Prevotella nigrescens, and Prevotella intermedia, most of which were enriched in the inflammation group and showed a significant positive correlation. A cross-validated random forest model based on the 26 different OTUs before the operation was able to fit the post-operative status of grafted sites and yielded a good classification result. The sensitivity and specificity of this classified model were 76.9% and 86.7%, respectively. These findings show that the oral microbiota profile before alveolar bone grafting may be related to the risk of post-operative inflammation at grafted sites.

Evaluation of the Microbiological Profile of Alveolar Residual Screws and Cleft-Adjacent Teeth in Individuals With Complete Unilateral Fissures

“…The number of individuals selected for the study (n = 20) was chosen based on previous studies that analyzed the same population profile (Mombelli et al, 1992; Huynh-Ba et al, 2009; Liu et al, 2016; Zhang et al, 2016; Machorowska-Pieniczek et al, 2017). All patients in the study had unilateral complete cleft palates, which had been submitted to surgical closure.…”

“…The oral microbiota in individuals with cracks has been evaluated by several authors (Mombelli et al, 1992; Costa et al, 2003; Tuna et al, 2008; Cocco et al, 2010; Liu et al, 2016; Zhang et al, 2016; Machorowska-Pieniczek et al, 2017; Funahashi et al, 2019). Mombelli et al (1992) used microbiological culture and characterized the microbiota isolated from the crevices and periodontal sites of adjacent teeth in adult individuals and demonstrated that microbiological compositions did not differ between the slits and the dental sites.…”

“…Tuna et al (2008) indicated a positive correlation between frequency of Staphylococcus aureus transmission and fistula size. Cocco et al (2010) and Liu et al (2016) considered that the presence of pathogenic bacteria (beta-hemolytic streptococci, Tannerella sp., Porphyromonas sp., Gemella sp., Moraxella sp., P nigrescens , and Prevotella intermedia ) was associated with a higher risk of postoperative inflammation. Using recent methodological techniques, Zhang et al (2016) found a disturbed ecological ecosystem in oral and nasal microbiome of children with cleft palate as a consequence of the abnormal communication between the 2 cavities.…”

“…To date, few studies have analyzed the microbiota of alveolar slits, and those already published have focused on a limited number of bacterial species. It is also important to highlight that the presence of bacteria in the oral cavity with pathogenic potential in other regions of the human body may pose a potential risk to the general health of the individual (Vebo et al, 2009; Vu & Carvalho, 2011; Valour et al, 2013; Liu et al, 2016). Thus, a more detailed knowledge of the microbiota installed in this niche is important for the delineation of therapeutic procedures for the prevention of possible infections in this specific group of individuals.…”

Microbiome in oral and maxillofacial surgery

“…Schmidt et al 4 studied that the microbiome may provide a framework for monitoring oral cancer development, progression and recurrence. Liu et al 5 reported that the risk of post-operative inflammation at grafted sites might be related to the oral microbiota profile before alveolar bone grafting. Also, Pushalkar et al 6 suggested that colonization of unique bacterial communities coupled with deficient innate immune response is likely to impact the pathogenesis of osteonecrosis of the jaw.…”