How Periodontitis or Periodontal Bacteria Can Influence Alzheimer's Disease Features? A Systematic Review of Pre-Clinical Studies.

BACKGROUND: The negative effects of periodontitis on systemic diseases, including diabetes, cardiovascular diseases, and Alzheimer's disease (AD), have been widely described. OBJECTIVE: This systematic review aimed to gather the current understanding of the pathophysiological mechanisms linking periodontitis to AD. METHODS: An electronic systematic search of the PubMed/MEDLINE, Scopus, and Embase databases was performed using the following PECO question: How can periodontitis or periodontal bacteria influence Alzheimer's disease features?". Only preclinical studies exploring the biological links between periodontitis and AD pathology were included. This study was registered at the International Prospective Register of Systematic Reviews (PROSPERO), and the Syrcle and Camarades protocols were used to assess the risk of bias. RESULTS: After a systematic screening of titles and abstracts (n = 3,307), thirty-six titles were selected for abstract reading, of which 13 were excluded (k = 1), resulting in the inclusion of 23 articles. Oral or systemic exposure to periodontopathogens or their byproducts is responsible for both in situ brain manifestations and systemic effects. Significant elevated rates of cytokines and amyloid peptides (Aß) and derivate products were found in both serum and brain. Additionally, in infected animals, hyperphosphorylation of tau protein, hippocampal microgliosis, and neuronal death were observed. Exposure to periodontal infection negatively impairs cognitive behavior, leading to memory decline. CONCLUSIONS: Systemic inflammation and brain metastatic infections induced by periodontal pathogens contribute to neuroinflammation, amyloidosis, and tau phosphorylation, leading to brain damage and subsequent cognitive impairment.

Predicting probing depth reduction after periodontal non-surgical treatment in smokers according to the nicotine dependence and the number of cigarette consumed.

Introduction: Smoking is considered as a risk factor for the poor outcomes after periodontitis non-surgical treatment (PNST). The aim of this short communication is to predict probing depth reduction after periodontal non-surgical treatment in smokers according to the nicotine dependence (FTND) and the number of cigarette consumed (NCC). Methods: This work is a post-hoc study of a prospective controlled study on the effect of oral hygiene instructions and PNST on periodontal outcomes. This short communication focused only on the current conventional smokers (N = 34), based on specific smoking indicators, and on probing depth (PD) parameter that were recorded at baseline (time 0), after oral hygiene instruction (time 1) and 3 months after PNST (time 2). Results: The 34 smokers had a mean age 46.5 ± 11.5 years. The NCC- and FTND-based predictions allowed to show in a specific nomogram the PD values 3 months after PNST for each NCC and FTND category. Conclusion: Two nomograms are proposed for prognostic purposes and allow patients to understand the impact of smoking on periodontitis according to the number of cigarette consumed and the level of nicotine dependence. These nomograms might be also used for supporting smoking cessation. Clinical significance: In smoker patients with periodontitis, there is a need to predict, for both patient and clinicians, the impact of the number of cigarettes consumed and the level of nicotine dependence on probing depth after oral hygiene instructions and debridement. Two nomograms are proposed for prognostic purposes.

Update on the Bidirectional Link Between Diabetes and Periodontitis.

AIM: To provide an update on the evidence on the bidirectional relationship between periodontitis and diabetes. METHODS: This narrative review was focused on recent studies between 2015 and 2020. The literature search was performed on PubMed. The inclusion criteria were systematic reviews, consensus reports and controlled trials assessing the effect of diabetes on periodontitis, the effect of periodontitis on diabetes, and the influence of periodontitis non-surgical treatment on diabetes. RESULTS: Data concerning the influence of periodontitis on diabetes, and the influence of diabetes on periodontitis were summarized in descriptive tables. CONCLUSION: The control of hyperglycemia in the prevention of periodontitis and the control of periodontitis systemic inflammation in the prevention of diabetes, should be take into account in the treatment planning of both diseases.

Update on the Roles of Oral Hygiene and Plaque Control on Periodontal Disease.

AIM: to provide an update of the evidence on the effect of oral hygiene instructions (OHI), dental plaque control and in the prevention and treatment of periodontitis. METHODS: Literature searches were performed using MeSH terms, keywords and free words and were published between 2015 and November 2020. The data from the articles were summarized in a narrative review. RESULTS: Data concerning the influence of OHI on periodontal features, the impact of OHI before periodontitis non-surgical treatment, its efficacity on periodontitis prevention and maintenance of healthy periodontium were summarized in the tables of the present narrative review. CONCLUSION: as prevention is better than a cure, it is relevant to bring in light the role of oral hygiene instructions, the patient self-control of dental plaque as well as the professional mechanical plaque removal in the prevention of periodontitis.

Fagerström test for nicotine dependence as an indicator in tobacco-related studies in periodontology.

BACKGROUND: Smoking is considered a risk factor for periodontitis genesis and progression. Numerous clinical studies have demonstrated the negative effect of smoking, in particular the number of cigarettes consumed (NCC), on periodontal clinical parameters. However, smoking addiction assessed by the Fagerström test for nicotine dependence (FTND) has received little attention in periodontal research. METHODS: In smoking patients presenting with periodontitis, the periodontal clinical features were measured and correlated with smoking status. The ability of FTND and NCC to predict periodontitis severity was assessed and compared. RESULTS: Thirty-four smoking patients aged 46.5 ± 11.5 years were included. The means of NCC and FTND were 16.6 ± 5.5 and 5.2 ±1.8, respectively. NCC and FTND were correlated with each other (r = 0.57, P < 0.001). Patients had stage III (44.1%) or stage IV (55.9%) periodontitis and 73.5% presented a generalized extension of periodontitis. The combination of FTND and NCC in discerning disease severity (ROC curve analysis: AUC = 0.746, P = 0.027) was superior to each indicator separately. A discriminant score based on both indicators (D = -0.42 - 0.15 × NCC + 0.63 × FTND) derived by logistic regression showed the opposite role of the indicators and the greater relevance of FTND (P = 0.031) compared to NCC (P = 0.084) in the relationship. CONCLUSION: This study shows that FTND could substantially complement NCC as an indicator of smoking status in periodontal research.

Blood Biomarkers and Serologic Immunological Profiles Related to Periodontitis in Abdominal Aortic Aneurysm Patients.

BACKGROUND: Periodontitis is a chronic inflammatory gum disease associated with systemic diseases such as cardiovascular diseases. AIM: To investigate the association of systemic blood biomarkers, C-reactive protein (CRP), levels of lipopolysaccharide (LPS), and IgG levels against periodontal pathogens Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) with the stability, based on the aortic diameter, the growth rate and the eligibility for surgical intervention, of patients with abdominal aortic aneurysm (AAA). METHODS: Patients with stable AAA (n = 30) and unstable AAA (n = 31) were recruited. The anti-A. actinomycetemcomitans and anti-P. gingivalis IgG levels were analyzed by ELISA, the LPS analysis was performed by using the limulus amebocyte lysate (LAL) test, and plasma levels of CRP were determined using an immune turbidimetric method. The association between these blood systemic biomarkers, AAA features, periodontal clinical parameters and oral microbial profiles were explored. Regression models were used to test the relationship between variables. RESULTS: The presence of antibodies against Pg and Aa, LPS and high CRP concentrations were found in all AAA patients. The IgG levels were similar in patients with stable and unstable AAA (both for Aa and Pg). Among investigated blood biomarkers, only CRP was associated with AAA stability. The amount of LPS in saliva, supra, and subgingival plaque were significantly associated with the systemic LPS (p <0.05). CONCLUSIONS: This post-hoc study emphasizes the presence of antibodies against Pg and Aa, LPS and high CRP concentrations in all AAA patients. The presence of Pg in saliva and subgingival plaque was significantly associated with the blood LPS levels. For further studies investigating periodontitis and systemic diseases, specific predictive blood biomarkers should be considered instead of the use of antibodies alone.

Respective Effects of Oral Hygiene Instructions and Periodontal Nonsurgical Treatment (Debridement) on Clinical Parameters and Patient-Reported Outcome Measures with Respect to Smoking.

BACKGROUND: Oral hygiene instructions (OHI) and periodontal nonsurgical treatment (PNST) play pivotal roles in the management of periodontitis. The study aims to discern their respective effects on periodontal clinical parameters and patient-reported outcome measures (PROMs). METHODS: Ninety-one patients were included, 34 non-smokers (NS), 25 former smokers (FS) and 32 current smoker (CS). Clinical parameters such as probing depth (PD) and bleeding on probing (BOP) were collected, and the periodontal inflamed tissue area (PISA) was calculated. Clinical parameters and PROMs were recorded before and after receiving OHI, with electronic tooth brush and interdental brushes, as well as 3 months after debridement. RESULTS: Smokers presented a significantly higher proportion of severe periodontitis (64.7%) with generalized extension (76.5%) and with a rapid rate of progression (97.1%) compared to NS and FS. OHI led to a significant decrease of PD, BOP, and PISA (p < 0.0001) only in NS and FS. Debridement reduced PD and the percentage of PD >6 mm in all groups (p < 0.0001). OHI induced significant improvement of oral hygiene, frequency of interdental cleaning, and PROMs (p < 0.0001). Further debridement induced significant additional improvement PROMs in FS and NS (p < 0.0001). CONCLUSION: OHI and debridement improved periodontal clinical parameters and PROMs in both NS and FS. Former smokers had comparable outcomes to non-smokers, suggesting that smoking cessation should be encouraged.

Tunnel/Pouch versus Coronally Advanced Flap Combined with a Connective Tissue Graft for the Treatment of Maxillary Gingival Recessions: Four-Year Follow-Up of a Randomized Controlled Trial.

BACKGROUND: The long-term stability after soft tissue graft for covering gingival recession remains a pivotal goal for both patient and periodontist. Therefore, the aim of this study was to compare the four-year outcomes of the coronally advanced flap (CAF) versus the pouch/tunnel (POT) technique, both combined with connective tissue graft (CTG), for gingival recession treatment. METHODS: Forty patients were initially randomly assigned to the control group (CAF + CTG; N = 20) and the test group (POT + CTG; N = 20). Clinical outcomes included mean root coverage (MRC) and complete root coverage (CRC), gingival thickness (GT), and keratinized tissue (KT) gain. Esthetic outcomes were also analyzed using the pink esthetic score (PES) and patient-reported outcome measures (PROMs). All outcomes initially assessed at six months were extended to four years post-surgery. RESULTS: No significant differences were observed between the two patient groups in terms of MRC and CRC. At four years, significantly greater GT and KT gain were noted in the POT + CTG group, and tissue texture enhancement was also more prominent in the test group. CONCLUSIONS: The POT + CTG technique allows for long-term clinical coverage of gingival recessions comparable to that of the CAF + CTG technique, but it potentially improves gingival thickness, keratinized tissue and esthetic results.

Further evidence on the relationship between abdominal aortic aneurysm and periodontitis: A cross-sectional study.

BACKGROUND: Periodontitis is a chronic inflammatory disease characterized by Gram-negative bacteria responsible for the degradation of tissues surrounding tooth. Moreover, periopathogens can invade the bloodstream, disseminate and promote cardiovascular disease, such as the link between Porphyromonas gingivalis and atherosclerosis. The aim of this study was to explore the relationship between the severity of periodontitis and of abdominal aortic aneurysm (AAA). METHODS: This cross-sectional study compared patients with stable AAA (n = 30) and patients with unstable AAA (n = 31) based on aortic diameter, growth rate, and eligibility for surgical intervention. Periodontal clinical parameters were recorded as well as the Periodontal Inflamed Surface Area and the Periodontal Index for Risk of Infectiousness (PIRI). Microbiological analyses were performed on saliva and supragingival and subgingival plaque. Quantification of Tannerella forsythia (Tf), Porphyromonas gingivalis (Pg), Aggregatibacter actinomycetemcomitans (Aa), Fusobacterium nucleatum (Fn), and Prevotella intermedia (Pi) was done by quantitative polymerase chain reaction. RESULTS: The two AAA groups were homogeneous for age, sex, and most risk factors except hypertension and chronic obstructive pulmonary disease. Periodontal parameters were comparable but the proportion of patients with high PIRI scores was greater in those with unstable AAA (51.6% versus 23.3%). The probing depth (PD) and the proportion of PD >6 mm were positively correlated with AAA size and thrombus volume. Several associations were found between periopathogens such as Pg and AAA diameters and volumes, but no difference could be evidenced between stable and unstable AAA groups. CONCLUSIONS: Periodontitis was highly prevalent in both stable and unstable AAA patients. Severe and progressive periodontitis (stage IV and grade C) tended to be more frequent in the group of patients with unstable AAA. Moreover, Pg was observed in all the samples (saliva, supragingival, and subgingival plaque) and was correlated with AAA diameters and volumes. The study evidenced potential relationships between periodontitis severity and size of AAA.

Can Periodontitis Influence the Progression of Abdominal Aortic Aneurysm? A Systematic Review.

There is some evidence that periodontitis increases the risk of atherothrombosis. Abdominal aortic aneurysm (AAA) is a cardiovascular disease with specific risk factors and physiopathological mechanisms that can lead to rupture in the absence of treatment. The aim of the present systematic review was to explore the influence of periodontitis on the progression of AAAs as a specific disease. A systematic search in PubMed/MEDLINE and Embase databases was performed. Human and animal studies exploring the influence of periodontal pathogens on the progression of AAA were considered for inclusion. After systematic screening, 5 articles were included in the review. Due to the heterogeneity of the selected studies, a meta-analysis could not be performed. The descriptive analyses of the studies emphasized that periodontal pathogens or their by-products contribute to systemic and local innate immunity likely to be associated with AAA physiopathology. Periodontitis seems to play a role in the development and progression of AAA. The present systematic review suggests that the presence of periodontal bacteria in the bloodstream or in situ in the vascular lesion is a risk associated with aneurysmal disease progression.

The effectiveness of a resorbable bone substitute with a resorbable membrane in the treatment of periodontal infrabony defect - A multicenter randomised controlled trial.

PURPOSE: To evaluate the effectiveness of a bone substitute covered with a resorbable membrane versus open flap debridement for the treatment of periodontal infrabony defects. MATERIALS AND METHODS: Ninety-seven patients with one infrabony defect, which was 3 mm or deeper and at least 2 mm wide were randomly allocated either to grafting with a bone substitute covered with a resorbable barrier (BG group) or open flap debridement (OFD group) according to a parallel group design in five European centres. Blinded outcome measures assessed tooth loss, complications, patient's satisfaction with treatment and aesthetics, changes in probing attachment levels (PAL), probing pocket depths (PPD), gingival recessions (REC), radiographic bone levels (RAD) on standardised periapical radiographs, plaque index (PI) and marginal bleeding index (MBI). RESULTS: 49 patients were randomly allocated to the BG group and 48 to the OFD group. At baseline there were more mobile teeth in the BG group (29 versus 15). One year after treatment two patients dropped out from the BG group and no teeth were lost. Three complications (minor postoperative wound dehiscence) occurred in the BG group versus none in the OFD group, where the difference was not statistically significant. The BG group obtained significantly greater statistical PAL gain (mean difference = -0.8 mm, 95% CI [-1.51; -0.03], P = 0.0428), PPD reduction (mean difference = -1.1 mm, 95% CI [-1.84; -0.19], P = 0.0165) and RAD gain (mean difference = -1.2 mm, 95% CI [-2.0; -0.4], P = 0.0058) compared to the OFD group. No statistically significant differences between the groups were observed for gingival recession, or the patient's satisfaction with the treatment and aesthetics. There were some statistically significant differences between the centres for PAL and PPD with the Italian centres reporting better outcomes. CONCLUSIONS: The use of a bone substitute covered with a resorbable membrane yielded significantly better statistical clinical outcomes than open flap debridement in the treatment of periodontal infrabony defects deeper than 3 mm, with regard to PAL gain, PPD reduction and RAD gain.

Coronally advanced flap versus the pouch technique combined with a connective tissue graft to treat Miller's class I gingival recession: a randomized controlled trial.

AIM: The objective of this study was to compare two different periodontal plastic surgery procedures to treat Miller's class I recession: a coronally advanced flap(control group) versus the pouch technique (test group), both of which were associated with connective tissue graft. METHODS: Forty consecutive patients were included, with 20 patients being allocated for each group. The level of recession coverage, the keratinized tissue (KT)quantity, gingival aesthetics (PES) and post-operative outcomes were assessed for a follow-up period of 6 months. RESULTS: After 6 months, both techniques allowed for the excellent mean root coverage of 96.3 plus/minus 12.1% in the control group and of 91.3 plus/minus 17.6% in the test group.Complete root coverage was achieved in 89.5% (17/19) and 79% (15/19) of the recession cases in the control and the test groups respectively. A significant increase in KT height (p = 0.0011) was observed in the test group. A significant improvement in the pink aesthetic score was found in the two groups, but gingival texture displayed significantly better results in the test group (p < 0.0001). No significant difference between the two groups was found in terms of the morbidity outcomes. Pain killer consumption was similar in the two groups and significantly decreased over time. CONCLUSIONS: Both surgical techniques are relevant in treating Miller's class I recession. The pouch technique seems to increase the height of KT better and provides good gingival-related aesthetic outcomes.