The present study used 16S rRNA gene amplicon sequencing to assess the impact on salivary microbiome of different grades of dental and periodontal disease and the combination of both (hereinafter referred to as oral disease), in terms of bacterial diversity, co-occurrence network patterns and predictive models. Our scale of overall oral health was used to produce a convenience sample of 81 patients from 270 who were initially recruited. Saliva samples were collected from each participant. Sequencing was performed in Illumina MiSeq with 2 × 300 bp reads, while the raw reads were processed according to the Mothur pipeline. The statistical analysis of the 16S rDNA sequencing data at the species level was conducted using the phyloseq, DESeq2, Microbiome, SpiecEasi, igraph, MixOmics packages. The simultaneous presence of dental and periodontal pathology has a potentiating effect on the richness and diversity of the salivary microbiota. The structure of the bacterial community in oral health differs from that present in dental, periodontal or oral disease, especially in high grades. Supragingival dental parameters influence the microbiota’s abundance more than subgingival periodontal parameters, with the former making a greater contribution to the impact that oral health has on the salivary microbiome. The possible keystone OTUs are different in the oral health and disease, and even these vary between dental and periodontal disease: half of them belongs to the core microbiome and are independent of the abundance parameters. The salivary microbiome, involving a considerable number of OTUs, shows an excellent discriminatory potential for distinguishing different grades of dental, periodontal or oral disease; considering the number of predictive OTUs, the best model is that which predicts the combined dental and periodontal status.

PMR systems, particularly with combinations of a superior plus an inferior quadrant, could be useful to evaluate periodontal status based on PD and CAL. This tool could be useful for epidemiologic surveys on periodontal status.

Periodontal disease is a common worldwide oral inflammation/infection affecting tissues that surround and support teeth. This study aims to evaluate the prevalence, extent and severity of periodontal diseases and its risk factors, according to the most recent periodontal classification, in an adult population of Northern Portugal. This observational study collected data from clinical records of patients who attended the University Clinic of Gandra between April 2021 and April 2022. Of a total of 941 patients included, 457 (48.6%) had periodontitis, 253 (26.9%) had gingivitis and the remaining 231 (24.5%) were healthy patients. The prevalence of stage III severe periodontitis was 51.2%, more prevalent in males, and in the age group of 61–70 years. Gingivitis was more prevalent in females, and in the age group of 31–40 years; in both diseases, the most prevalent extension was the generalized one. Using a binary logistic regression, we observe a significant relation of the risk of periodontitis with age (p = 0.019; OR 1.033; 95% CI 1.005–1.062), tooth brushing (p = 0.002; OR 0.25; 95% CI 0.105–0.599) and dental flossing (p = 0.015; OR 0.63; 95% CI 0.09–0.768). This study revealed a high prevalence of periodontitis. Increased age, lack of tooth brushing and flossing were identified as potential risk factors for periodontitis in the investigated Portuguese population.

Objectives: In this paper we propose a new Global Oral Health Scale that will allow the infectious potential of the oral cavity, clinically manifest as local and focal infections, to be condensed into a single parameter. Study Design: Based on a number of oral health scales previously designed by our group, we designed a final version that incorporates dental and periodontal variables (some of them evaluated using corroborated objective indices) that reflect the presence of caries and periodontal disease. Results: The application of the proposed oral health scale requires the examination of 6 sites per tooth (mesio-buccal, medio-buccal, disto-buccal, disto-lingual, medio-lingual and mesio-lingual). The following variables are analysed: number of tooth surfaces with supragingival plaque, determined using the O’Leary index; number of teeth with caries and the severity of the caries; number of tooth surfaces with gingival inflammation, determined using the Ainamo and Bay index; and number of tooth surfaces with pockets ?4 mm and severity of the pockets. These variables are then grouped into 2 categories, dental and periodontal. The final grades of dental and periodontal health correspond to the grades assigned to a least 2 of the 3 variables analysed in each of these categories. The category (dental or periodontal) with the highest grade is the one that determines the grade of the Global Oral Health Scale. Conclusion: This scale could be particularly useful for the epidemiological studies comparing different populations and for analysis of the influence of distinct degrees of oral health on the development of certain systemic diseases. Key words:Scale, oral health, infectious potential, systemic disease.

The Q1+Q3 combination could be particularly applicable in studies investigating relationships between the state of gingival health and environmental or patient-related systemic factors, as well as in the development of oral health scales that include gingival parameters.