Subgingival bacterial clusters and serum antibody response as markers of extent and severity of periodontitis in adult Chinese

Efficacy of Platelet-rich Fibrin for the Treatment of Grade II Furcation Defects in Mandibular Molars

Aim:

To evaluate the efficacy of platelet-rich fibrin (PRF) in the treatment of grade II furcation mandibular molars.

Materials and Methods:

We enrolled 12 patients with 24 mandibular class II furcation defects in this randomized clinical trial with a split-mouth design. These defects were treated with either open flap debridement (OFD) in conjunction with PRF (test group) or only OFD (control group). We recorded and assessed clinical parameters (probing pocket depth [PPD], gingival recession [GR], and vertical and horizontal clinical attachment level [VCAL and HCAL, respectively]), radiographic parameters (bone defect fill [%BF]), and microbiological parameters at baseline and 6 months after treatment.

Results:

After treatment, PPD, VCAL, HCAL, BF, and microbiological parameters were significantly reduced in both groups. All clinical and radiographic parameters showed significant improvement at the sites that had been treated with PRF and OFD compared with those that had been treated with OFD alone. Among 24 furcation defects in both groups, 10 showed a significantly improved clinical condition and 14 remained at the initial grade. There were no more severe conditions recorded after treatment.

Conclusion:

Within the limitation of this article, we have demonstrated the effectiveness of PRF in the regenerative treatment of grade II furcation defects.

Evaluation of the preventive care effectiveness in the adults with odontogenic infection given social and hygienic risk factors

Relevance. Odontogenic infection is one of the most important problems of dental science. The variety of anti-inflammatory oral hygiene products determines the need for targeted selection of preventive toothpastes and rinses, balms, foams, elixirs, as well as monitoring and training the algorithm of hygienic measures for a patient with an odontogenic infection. The aim of the study was to study the hygienic status of the adult population for the selection of individual oral hygiene products for odontogenic infection, taking into account social and hygienic factors.

Materials and methods. The study examined the prevalence of odontogenic infection in the adult population to determine the need for professional care and dental education. The study involved 198 people without somatic pathology, who were allocated into four groups according to the performed oral care and taking into account the dental status and the intensity of oral microbiota formation in the adult population. The patients were followed-up every week for one month. The study examined the simplified oral hygiene index by GreenVermillion (OHI-S), PMA index and Mühlemann and Son sulcus bleeding index, which allowed calculating the effectiveness of oral care products.

Results. The preventive care effectiveness evaluation showed an increase in the cleansing effect in the adult population over the entire study period. The anti-inflammatory effectiveness analysis demonstrated positive changes: by the end of the study, the PMA index was 51.52 ± 3.40% in group 1; it increased by a factor of 3 and amounted to 44.17 ± 2.77% in group 2; 56.51 ± 4.61% – in group 3, 48.95 ± 3.60% – in group 4. The Mühlemann and Son sulcus bleeding index demonstrated the changes in the periodontal tissue condition and amounted to 52.78 ± 3.62% in group 1, 44.11 ± 3.54% in group 2, 54.97 ± 3.98% in group 3, 47.78 ± 2.73% in group 4.

Conclusions. The development of oral health promotion measures determines the significance of oral care products for the prevention of odontogenic infection in the adult population, which plays a crucial role in the individual program planning for the main dental disease prevention.

Oral Microbiome and Gingival Transcriptome Profiles of Ligature-Induced Periodontitis

This investigation evaluated the relationship of the oral microbiome and gingival transcriptome in health and periodontitis in nonhuman primates (Macaca mulatta). Subgingival plaque samples and gingival biopsies were collected from healthy sites and at sites undergoing ligature-induced periodontitis. Microbial samples were analyzed with 16S amplicon sequencing to identify bacterial profiles in young (3 to 7 y) and adult (12 to 23 y) animals. The gingival transcriptome was determined with a microarray analysis and focused on the expression level of 452 genes that are associated with the development of inflammation and innate and adaptive immune responses. Of the 396 total operational taxonomic units (OTUs) identified across the samples, 81.8% were detected in the young group and 99.5% in the adult group. Nevertheless, 58 of the OTUs composed 88% of the signal in adults, and 49 OTUs covered 91% of the OTU readouts in the young group. Correlation analyses between the microbiome members and specific gingival genes showed a high number of significant bacteria-gene correlations in the young healthy tissues, which decreased by 75% in diseased tissues. In contrast, these correlations increased by 2.5-fold in diseased versus healthy tissues of adult animals. Complexes of bacteria were delineated that related to specific sets of immune genes, differing in health and disease and in the young versus adult animals. The correlated gene profiles demonstrated selected pathway overrepresentation related to particular bacterial complexes. These results provide novel insights into microbiome changes with disease and the relationship of these changes to specific gene profiles and likely biologic activities occurring in healthy and diseased gingival tissues in this human-like periodontitis model.

Periodontitis phenotypes and clinical response patterns to non-surgical periodontal therapy: reflections on the new periodontitis classification

We aimed to identify response patterns to non-surgical periodontal therapy and to investigate whether the new classification system for periodontitis reflects response to treatment after 1 yr. At baseline, data on sociodemographic status, smoking, and diabetes were obtained from participants with periodontal disease. Clinical periodontal data and subgingival plaque were also collected. Participants underwent non-surgical periodontal therapy, and after 3 and 12 months, clinical data were reassessed. Factor analyses, group-based-trajectory modeling, and mixed-effects regression models were used for data analysis. Factor analysis of the baseline periodontal parameters revealed two different periodontitis dimensions: 'moderate' and 'severe'. Two response patterns for each of these periodontitis dimensions were identified. Periodontal therapy had a beneficial effect on both 'moderate' and 'severe' periodontitis; however, individuals with higher levels of disease at baseline experienced greater treatment effect. Regarding the new classification system, while the staging component distinguished different levels of 'moderate' and 'severe' periodontitis before and after treatment, the grading component did not. This study shows the beneficial effect of non-surgical periodontal therapy on both 'moderate' and 'severe' periodontitis. However, the benefit was limited among individuals with low levels of disease. The new classification system did not adequately reflect the periodontal response to therapy in this patient group.

Soluble urokinase-type plasminogen activator receptor is associated with signs of periodontitis in adolescents

Owing to its molecular stability in body fluids, soluble urokinase-type plasminogen activator receptor (suPAR) is used as a biomarker for the level of systemic inflammation. This study compares the suPAR levels in serum with those in the saliva of adolescents and evaluates their association with the periodontal conditions. Adolescents identified as screen positive (n = 87) or screen negative (n = 73) for periodontitis had saliva and serum samples taken, along with subgingival plaque samples. The concentrations of suPAR were determined in saliva and serum, and 18 microbial species and the immunoglobulin response to them was evaluated. Factor analyses were used to reduce the number of variables within each of the domains of clinical, microbiological, and immunological findings. The median salivary suPAR concentration was 13.18 [(interquartile range (IQR): 6.20-23.36] μg l^-1 and was not associated with the serum suPAR levels (median 2.05; IQR: 1.62-2.46 μg l^-1 ). Linear regression analysis showed that the log₁₀ (salivary suPAR concentration) was statistically significantly positively associated with the clinical phenotype 'Periodontitis Extent' (β = 0.28; 95% CI: 0.16-0.39) along with 'Putative periodontopathogens' (β = 0.65; 95% CI: 0.51-0.79). The study represents the first determination of salivary suPAR concentration in a larger well-defined adolescent population. Our results suggest the potential for clinical use of suPAR in saliva as an inflammatory risk indicator/biomarker of periodontitis.

Caries and Periodontitis: Contesting the Conventional Wisdom on Their Aetiology

We review the literature on the oral microbiome and the role of the microbiota in the development of dental caries and periodontitis. While most research has been focused on identifying one or more specific determinants of these diseases, the results have provided limited predictive value and have not been able to explain the variation in the distribution of these diseases observed in epidemiological or clinical studies. Drawing on existing knowledge about the nature of the oral microbiota, we suggest that a stochastic model based on the Weiner process provides simple and parsimonious explanations for the pathogenesis of both caries and periodontitis, making few assumptions, and providing explanations for phenomena that have hitherto proved difficult, or have required complex arguments, to explain. These diseases occur as the result of the dental hard tissues and periodontal tissues integrating the random "noise" caused by normal metabolic activities of commensal microorganisms in the dental biofilm. The processes that result in the progression and regression of caries and periodontitis may be considered as "natural," rather than pathological, even if, when left unchecked over long periods of time, they can result in the development of pathologies. The likelihood of progression or regression can be influenced by other determinants, but these processes will nevertheless occur in the absence of such influences. The distributional characteristics of the model approximate the findings of epidemiological studies indicating that, for both caries and periodontitis, there will be few sites affected in the early period after the eruption of the permanent dentition, but in those older there is an almost linear relationship with increasing age; furthermore, the longer a site survives without being affected, the less likely that it will be affected. We discuss the clinical and public health importance of these findings.

Multiplex real-time PCR detection and relative quantification of periodontal pathogens

Periodontitis is a chronic inflammatory disease, which is strongly associated with certain pathogenic bacteria. The aim of this study was to develop a real-time multiplex polymerase chain reaction (PCR) assay to detect and quantify bacterial species associated with periodontitis. We targeted detection and relative quantification of the following five bacterial species relevant to periodontal diseases: Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia. The conserved regions of the genome of these species were targeted with oligos and TaqMan probes in real-time PCR assays. The species-specific TaqMan oligos and TaqMan probes showed no cross-amplification, and there was no loss of amplification yield in multiplex real-time PCR assays. All five bacterial targets were amplified analogous to the template concentrations used in these assays. This multiplex real-time PCR strategy could potentially be used to detect the bacterial species in periodontal pockets of patients with periodontal diseases. This assay may also serve as a quick tool for profiling and quantifying bacteria relevant to periodontal diseases and likely be a valuable tool for clinical translational research.