RETRACTED ARTICLE: Peri-implantitis-associated methanogens: a preliminary report

Abstract

Methanogens have already been described in periodontitis but not in peri-implantitis. Thirty peri-implantitis samples and 28 control samples were collected in 28 consenting peri-implantitis patients. PCR-sequencing of the 16S rRNA gene was used as a broad-spectrum screening method and results were further confirmed by real-time quantitative PCR targeting the mcrA genes. Results showed a methanogen community dominated by Methanobrevibacter oralis in 31/58 (51%) samples including 16/28 (57%) control samples and 15/30 (50%) peri-implantitis samples. Methanobrevibacter massiliense was detected in 5/58 (8.6%) samples including 3/28 (1%) control samples and 2/30 (6.7%) peri-implantitis samples. The prevalence of M. oralis or M. massiliense did not significantly differ in peri-implantitis and control samples (exact Fisher test, P = 0.61 and P = 0.67, respectively). Further ponderation of the methanogen load by the real-time quantitative PCR for actin human gene again indicated non-significant difference (Wilcoxon-Mann-Whitney test, P = 0.48 and P = 0.40, respectively). These data show that the prevalence of methanogens does not differ in peri-implantitis lesions and healthy sites, when individuals are their own control. These data do not allow assigning a specific pathogenic role to methanogens in peri-implantitis; methanogens rather are part of the commensal and normal flora of the oral cavity.

Strong oral plaque microbiome signatures for dental implant diseases identified by strain-resolution metagenomics

“…Currently available studies investigating the link between the plaque microbiome and peri-implantitis have, however, important limitations. First, they all rely on the 16S rRNA gene sequencing approach 30 to profile the plaque microbiome 26 , 31 – 56 . Compared to the shotgun metagenomic approach 57 – 59 , this cost-effective technique is unable to identify most microbes at the species level and cannot profile the overall functional potential of the microbial community.…”

“…Compared to the shotgun metagenomic approach 57 – 59 , this cost-effective technique is unable to identify most microbes at the species level and cannot profile the overall functional potential of the microbial community. Second, the oral human microbiome 60 , 61 requires large sample sizes and intra-subject microbiome controls (i.e., contralateral sites) to account for its large inter-subject variability that are not considered in the available studies 35 , 39 , 40 , 46 , 47 , 49 , 51 , 55 , 56 . A recent study sampled multiple implants from the same individual but on a small cohort ( n = 18) of also periodontal patients 55 .…”

First characterization of methanogens in oral cavity in Malian patients with oral cavity pathologies

“…Also, methanogens have been implicated in oral cavity pathologies including Methanobrevibacter massiliense and M. oralis in cases of periimplantitis [4, 15].…”

Oral microbial profile variation during canine ligature-induced peri-implantitis development

“…OTU_3 and OTU_7 were identified as keystone taxa, suggesting these two strains might be one potential peri-implantitis cause [10]. The compositions of methanogens were higher at Phase T2 and Phase T3, but they were not keystone taxa, indicating methanogens might not be an indicator of peri-implantitis development [40]. Prevotella nigrescens was also identified to be associated with peri-implantitis lesion [12,41], but no Prevotella was identified in oral peri-implantitis microbiome in this study ( Table 2).…”