Tooth loss in aggressive periodontitis: a systematic review

Sinensetin protects against periodontitis through binding to Bach1 enhancing its ubiquitination degradation and improving oxidative stress

Periodontitis is a chronic inflammatory and immune reactive disease induced by the subgingival biofilm. The therapeutic effect for susceptible patients is often unsatisfactory due to excessive inflammatory response and oxidative stress. Sinensetin (Sin) is a nature polymethoxylated flavonoid with anti-inflammatory and antioxidant activities. Our study aimed to explore the beneficial effect of Sin on periodontitis and the specific molecular mechanisms. We found that Sin attenuated oxidative stress and inflammatory levels of periodontal ligament cells (PDLCs) under inflammatory conditions. Administered Sin to rats with ligation-induced periodontitis models exhibited a protective effect against periodontitis in vivo. By molecular docking, we identified Bach1 as a strong binding target of Sin, and this binding was further verified by cellular thermal displacement assay and immunofluorescence assays. Chromatin immunoprecipitation-quantitative polymerase chain reaction results also revealed that Sin obstructed the binding of Bach1 to the HMOX1 promoter, subsequently upregulating the expression of the key antioxidant factor HO-1. Further functional experiments with Bach1 knocked down and overexpressed verified Bach1 as a key target for Sin to exert its antioxidant effects. Additionally, we demonstrated that Sin prompted the reduction of Bach1 by potentiating the ubiquitination degradation of Bach1, thereby inducing HO-1 expression and inhibiting oxidative stress. Overall, Sin could be a promising drug candidate for the treatment of periodontitis by targeting binding to Bach1.

Tooth loss during supportive periodontal care: A prospective study

AIM

To assess periodontal stability and the association between tooth- and patient-related factors and tooth loss during supportive periodontal care (SPC).

MATERIALS AND METHODS

A prospective observational study was carried out on previously treated periodontitis patients followed up for 5 years in SPC. The risk profile (low, moderate, high) of each patient based on periodontal risk assessment (PRA) scoring at baseline was evaluated, and tooth loss rates were analysed.

RESULTS

Two hundred patients were included in the study, and 143 had 5-year follow-up data available for analysis. The overall annual tooth loss per patient was 0.07 ± 0.14 teeth/patient/year. Older age, smoking, staging and grading were associated with increased tooth loss rates. Most patients whose teeth were extracted belonged to the PRA high-risk group. Both PRA and a tooth prognosis system used at baseline showed high negative predictive value but low positive predictive value for tooth loss during SPC.

CONCLUSIONS

Overall, the tooth loss rate of periodontitis patients in this prospective cohort study under SPC in private practice was low. Both tooth-based and patient-based prognostic systems can identify high-risk cases, but their positive predictive value should be improved.

The survival of periodontally treated molars in long-term maintenance: A systematic review and meta-analysis

AIM

This systematic review and meta-analysis aimed to determine the survival of periodontally treated molars during maintenance care and identify the risk factors associated with molar loss among patients with periodontitis who received professional periodontal therapy and maintenance.

MATERIALS AND METHODS

Longitudinal studies with a minimum follow-up duration of 5 years published until 28 August 2023 were retrieved from the following databases: the Cochrane Library, Embase, MEDLINE and Web of Science. All included studies reported data on molar retention. Meta-analysis was performed using Review Manager 5.4. A modified version of the Newcastle-Ottawa Scale was used to evaluate the study quality. Statistical results of analyses of the overall survival rate and molar loss are presented as estimated standardized mean differences, whereas the results of the analyses of risk factors are presented as risk ratios with 95% confidence intervals (95% CIs).

RESULTS

From among the 1323 potentially eligible reports, 41 studies (5584 patients, 29,908 molars retained at the beginning of maintenance therapy, mean follow-up duration of 14.7 years) were included. The pooled survival rate of the molars during maintenance therapy was 82% (95% CI: 80%-84%). The average loss of molars was 0.05 per patient per year (95% CI: 0.04-0.06) among the patients receiving long-term periodontal maintenance (PM) therapy. Fifteen factors were examined in this meta-analysis. Six patient-related factors (older age, lack of compliance, smoking, bruxism, diabetes and lack of private insurance) and five tooth-related factors (maxillary location, high probing pocket depth, furcation involvement, higher mobility and lack of pulpal vitality) were identified as risk factors for molar loss during maintenance therapy.

CONCLUSIONS

The findings of the present study suggest that the long-term retention of periodontally compromised molars can be achieved. The average number of molars lost per decade was <1 among the patients receiving long-term PM therapy. Older age, noncompliance, smoking, bruxism, diabetes, lack of private insurance coverage, maxillary location, furcation involvement, higher mobility, increase in the probing pocket depth and loss of pulpal vitality are strong risk factors for the long-term prognosis of molars.

The long-term effect of periodontitis treatment on changes in blood inflammatory markers in patients with generalized aggressive periodontitis

BACKGROUND

Periodontitis is characterized by local inflammatory conditions in the periodontium, its severe form has been associated with elevated systemic inflammatory markers. However, the long-term effects of periodontal inflammation control on systemic inflammatory markers are unclear.

OBJECTIVE

This study aimed to investigate the long-term effects of periodontal therapy on the levels of peripheral venous blood inflammatory markers in patients with generalized aggressive periodontitis (GAgP), all of whom were now diagnosed as Stage III or IV Grade C periodontitis.

METHODS

Patients with GAgP were consecutively recruited from April 2013 to August 2014 (T0). Active periodontal treatment (APT) was provided, and follow-ups were conducted over a 3- to 5-year period (T1). Clinical parameters were assessed and fasting venous blood was collected at T0 and T1. Complete blood cell counts were obtained, and biochemical analyses were performed to evaluate the levels of serum components. The correlations between probing depth (PD) and hematological parameters were analyzed.

RESULTS

A total of 49 patients with GAgP completed APT and follow-ups. Probing depth (PD) reduced from 5.10 ± 1.07 mm at T0 to 3.15 ± 0.65 mm at T1. For every 1-mm reduction in PD after treatment, the neutrophil count, neutrophil-lymphocyte ratio, and total protein concentration were reduced by 0.33 × 109 /L, 0.26, and 1.18 g/L, respectively. In contrast, the albumin/globulin ratio increased by 0.10.

CONCLUSION

This study indicated that periodontal therapy may have beneficial effects on peripheral venous blood inflammatory markers in patients with GAgP during long-term observation.

Prevalence of periodontitis in Saudi Arabia: A systematic review and meta-analysis

Objective

The aim of this systematic review was to assess the prevalence of periodontal disease among Saudi Arabian adults based on studies conducted from 1992 to 2023.

Methods

The study protocol was registered in PROSPERO. Three databases (MEDLINE, EMBASE and Cochrane library) and the Saudi Dental Journal were searched for published literature up to June 2023 using prespecified search strategy. Quality of included studies was checked using the risk of bias in population-based prevalence studies tool.

Results

The systematic review included 15 studies that assessed the prevalence of periodontal disease in Saudi Arabia. Most of the studies used non-confident case definitions. The pooled estimate of periodontal disease prevalence in Saudi Arabia based on the data of 14 which included 6,596 individuals is 51% (95% CI: 35.99, 73.05).

Conclusion

Periodontal disease is a significant public health issue in Saudi Arabia, with a substantial prevalence among the included participants. Nevertheless, the existing studies exhibit methodological disparities and regional limitations. Therefore, while the results shed light on the pressing nature of periodontal disease in Saudi Arabia, further comprehensive research is imperative. A more accurate estimate, coupled with effective strategies, can be achieved through broader, multidisciplinary collaborations and the prioritization of a national oral health survey in Saudi Arabia.

Periodontitis in young individuals: Important factors for disease progression

AIM

To investigate the progression of periodontitis in young individuals and identify factors that contribute to progression rate and whether periodontitis stage and grade have an impact on disease progression.

MATERIALS AND METHODS

This retrospective cohort study was based on patients younger than 36 years at two periodontal clinics between 2003 and 2009. At least 10 years later, a clinical and radiographic examination was performed on 215 patients. The marginal bone loss between baseline and follow-up for the tooth with the most severe bone loss at follow-up was estimated by radiographic measurements. Linear regression analysis was used to investigate the influence of potential risk indicators on periodontitis progression.

RESULTS

Most patients (83%) were classified as periodontitis stage III at baseline. At follow-up, 70% of these patients remained in stage III. The frequency of patients with grade C decreased from 79% to 17% at follow-up. The median (Q25%; Q75%) of the longitudinal marginal bone loss was 0.5 mm (0.0; 2.0). High bleeding on probing (BOP) index at baseline, smoking and interruption of periodontal treatment were found to significantly increase longitudinal bone loss.

CONCLUSIONS

High levels of BOP at baseline, smoking and interruption of periodontal treatment increased the risk of marginal bone loss. The stage and grade at baseline had no significant impact on disease progression.

Knockdown of Bach1 protects periodontal bone regeneration from inflammatory damage

Periodontal bone regeneration is a major challenge in the treatment of periodontitis. However, the regenerative vitality of periodontal ligament cells (PDLCs) declines in the environment of periodontitis and accompanying oxidative stress. This study aimed to investigate the functional mechanisms of Bach1, a transcriptional suppressor involved in oxidative stress response, and its regulation of PDLC osteogenesis under inflammatory conditions. We observed a significant elevation in Bach1 expression in periodontal tissues with periodontitis and PDLCs under inflammatory conditions. Knockdown of Bach1 alleviated the inflammation-induced oxidative stress level and partly offset the inhibitory effect of inflammatory conditions on osteogenesis, as well as the expression of osteogenic genes BMP6, OPG and RUNX2. Similarly, knockdown of Bach1 protects PDLCs from inflammatory damage to periodontal bone regeneration in vivo. Furthermore, we found that Bach1 could bind to the histone methyltransferase EZH2, and the binding increased under inflammatory conditions. Bach1 enhanced the ability of EZH2 to catalyse H3K27me3 on the promoter region of RUNX2 and BMP6, thus repressing the expression of osteoblastic genes. In conclusion, our study revealed that knockdown of Bach1 effectively rescued the osteogenesis and oxidative stress of PDLCs with inflammation. Bach1 could be a promising target for enhancing periodontal tissue regeneration under periodontitis conditions.

Involvement of ferroptosis in Porphyromonas gingivalis lipopolysaccharide-stimulated periodontitis in vitro and in vivo

OBJECTIVES

Ferroptosis is associated with multiple inflammatory diseases. Periodontitis is an inflammatory disease mainly caused by oral opportunistic pathogens. However, the ferroptosis-periodontitis relationship has not been thoroughly described. We here analyzed whether ferroptosis is involved in periodontitis.

MATERIALS AND METHODS

Human gingival fibroblasts (HGFs) were stimulated with P. gingivalis-LPS and ferrostatin-1 (Fer-1, a ferroptosis inhibitor), and changes in mitochondrial morphology, ferroptosis-related factors, and inflammation levels were detected. After the rat experimental periodontitis model was established, changes in ferroptosis-related factors and inflammation levels were re-evaluated in the same manner.

RESULTS

Porphyromonas gingivalis-LPS-induced mitochondrial shrinkage, an increase in mitochondrial membrane density, and upregulation of reactive oxygen species in HGFs. The expression of prostaglandin-endoperoxide synthase 2, transferrin receptor 1, and malondialdehyde and inflammation levels were upregulated, whereas the expression of solute carrier family seven member 11, glutathione peroxidase 4, superoxide dismutase, and glutathione were downregulated. Fer-1 attenuated these aforementioned changes and inflammation levels induced by P. gingivalis-LPS. The in vivo experiment results were consistent with the in vitro experiment results.

CONCLUSIONS

Ferroptosis is involved in inflammatory processes in HGFs upon P. gingivalis-LPS stimulation. Ferroptosis is observed in the gingival tissue of periodontitis rats.

Suspension of oral hygiene practices highlights key bacterial shifts in saliva, tongue, and tooth plaque during gingival inflammation and resolution

Experimentally induced gingivitis is associated with inflammatory and microbiological changes in an otherwise healthy subject, demonstrating the impacts of discontinuing oral hygiene routines. Understanding the bacterial dynamics during the induction and resolution of gingival inflammation will aid in the development of bacterial prognostic tests and probiotics for severe oral disease. We profiled the bacterial community in 15 healthy subjects who suspended all oral-hygiene practices for three weeks. Saliva, tongue, subgingival, and supragingival plaque samples were collected over seven weeks and showed a return to community baseline after oral hygiene practices were resumed. Stronger temporal changes in subgingival and supragingival plaque suggest these sample types may be preferred over saliva or tongue plaque for future prognostics. Taxonomic groups spanning ten phyla demonstrated consistent abundance shifts, including a significant decrease in Streptococcus, Neisseria, and Actinomyces populations, and an increase in Prevotella, Fusobacterium, and Porphyromonas populations. With four distinct oral sites surveyed and results mapped to the Human Oral Microbiome Database reference set, this work provides a comprehensive taxonomic catalog of the bacterial shifts observed during the onset and resolution of gingival inflammation.

Hypertension and periodontitis: A joint report by the Italian society of hypertension (SIIA) and the Italian society of periodontology and implantology (SIdP)

An accumulating body of evidence supports an independent association between high blood pressure (BP) and periodontitis, possibly mediated by low-grade inflammation. This joint report by the Italian Society of Hypertension (SIIA) and the Italian Society of Periodontology and Implantology (SIdP) working group on Hypertension and Periodontitis (Hy-Per Group) provides a review of the evidence on this topic encompassing epidemiology, biological plausibility, relevance, magnitude, and treatment management. Consensus recommendations are provided for health professionals on how to manage BP in individuals showing signs of poor oral health. In summary, (1) large epidemiological studies highlight that individuals with periodontal diseases have increased risk for high/uncontrolled BP independent of confounders; (2) mechanistically, low-grade inflammation might have a causal role in the association; (3) BP profile and control might benefit from periodontal treatment in pre-hypertensive and hypertensive individuals; (4) oral health status should be evaluated as a potential risk factor for high/uncontrolled BP, and effective oral care should be included as an adjunct lifestyle measure during hypertension management. Further research is needed to optimize BP management in individuals with poor oral health.

Comparison of the efficacy of periodontal prognostic systems in predicting tooth loss

Aim

The aim of this analysis was to assess how different tooth‐prognosis systems could predict tooth loss in a cohort of periodontitis patients followed up prospectively during supportive periodontal care (SPC).

Materials and Methods

Clinical and radiographic data of 97 patients undergoing regular SPC for 5 years were used to assign tooth prognosis using four different systems (McGuire & Nunn, 1996; Kwok & Caton, 2007; Graetz et al., 2011; Nibali et al., 2017). Three independent examiners assigned tooth prognosis using all four systems, following a calibration exercise. The association between prognostic categories and tooth loss was tested for each prognostic system separately and across prognostic systems.

Results

All four systems showed good reproducibility and could identify teeth at higher risk of being lost during 5 years of SPC; the risk of tooth loss increased with the worsening of tooth‐prognosis category (p < .0001). Although specificity and negative predictive values were good, low sensitivity and positive predictive values were detected for all systems.

Conclusions

Previously published periodontal prognostic systems exhibited good reproducibility and predictive ability for tooth retention. However, low sensitivity was detected, with several teeth in the worst prognosis category being retained at 5 years. Some modifications in the number of categories and their definitions are suggested.

Hypertension and Periodontitis: A Joint Report by the Italian Society of Hypertension (SIIA) and the Italian Society of Periodontology and Implantology (SIdP)

An accumulating body of evidence supports an independent association between high blood pressure (BP) and periodontitis, possibly mediated by low-grade inflammation. This joint report by the Italian Society of Hypertension (SIIA) and the Italian Society of Periodontology and Implantology (SIdP) working group on Hypertension and Periodontitis (Hy-Per Group) provides a review of the evidence on this topic encompassing epidemiology, biological plausibility, relevance, magnitude, and treatment management. Consensus recommendations are provided for health professionals on how to manage BP in individuals showing signs of poor oral health. In summary, (1) large epidemiological studies highlight that individuals with periodontal diseases have increased risk for high/uncontrolled BP independent of confounders; (2) mechanistically, low-grade inflammation might have a causal role in the association; (3) BP profile and control might benefit from periodontal treatment in pre-hypertensive and hypertensive individuals; (4) oral health status should be evaluated as a potential risk factor for high/uncontrolled BP, and effective oral care should be included as an adjunct lifestyle measure during hypertension management. Further research is needed to optimize BP management in individuals with poor oral health.

Periodontal Surgery Combined with Multiple Extractions: A Case Report

BACKGROUND Dental extraction is the only treatment option for terminal stage periodontal disease. Remnants of the pathological periodontal tissue can still be present after the extraction. Periodontal flap surgery contributes to achieving a better regeneration process at the extraction site. This case report includes a unique unconventional approach to periodontal therapy, not commonly reported in the literature. CASE REPORT A 37-year-old man reported mobility and migration of the teeth in both jaws and was referred to the Periodontology Department of the University of Prishtina Dentistry School. The patient had no personal history of any current systemic condition or family history of similar gum conditions. After a clinical and radiographic evaluation (periodontal probing depth and gingival index), most of the front teeth of both jaws were diagnosed with terminal stage periodontal disease (stage 4, grade C). Modified Widman flap periodontal surgery was conducted on the maxilla and mandible to extract most of the front teeth. The sites of tooth extraction underwent profound debridement to remove the pathological soft tissues and sharp bone extrusions. The 4 postoperative follow-up visits at 1, 4, 8, and 10 weeks showed sufficient restitution of the wounds. He received temporary mobile prostheses for the areas with multiple extractions. After 10 weeks, he began treatment for a fixed prosthetic bridge. He had a satisfactory recovery and was followed up over 3 annual visits after his surgery. CONCLUSIONS Multiple extractions can be considered as a treatment option for terminal stage periodontitis.

Development of an miRNA-Array-Based Diagnostic Signature for Periodontitis

Periodontitis progression is accompanied by irreversible alveolar bone absorption and leads to tooth loss. Early diagnosis is important for tooth stability and periodontal tissue preservation. However, there is no recognized miRNA diagnostic signature with convincing sensitivity and specificity for periodontitis. In this study, we obtained miRNA array expression profiles of periodontitis from the Gene Expression Omnibus (GEO) database. After screening for differentially expressed miRNAs, the least absolute shrinkage and selection operator (LASSO) method was performed to identify and construct a 17-miRNA-based diagnostic signature (hsa-miR-3917, hsa-mir-4271, hsa-miR-3156, hsa-miR-3141, hsa-miR-1246, hsa-miR-125a-5p, hsa-miR-671-5p, hcmv-mir-UL70, hsa-miR-650, hsa-miR-497-3p, hsa-miR-145-3p, hsa-miR-141-3p, hsa-miR-210-3p, hsa-miR-204-3p, hsa-miR-203a-5p, hsa-miR-99a-3p, and hsa-miR-30a-3p). Periodontal tissue samples with higher risk scores were more likely to show symptoms of periodontitis. Then, the receiver operating characteristic (ROC) curves were used to assess the diagnostic value of the miRNA signature, which indicated that the optimum cutoff value in periodontitis diagnosis was 0.5056 with an area under the ROC curve (AUC) of 0.996, a sensitivity of 97.3%, a specificity of 100.0% in the training cohort; in the testing cohort, the corresponding values were as follows: an AUC of 0.998, a sensitivity of 97.9%, and a specificity of 91.7%. We next evaluated the efficacy of the signature in differentiating disease subtype and affected range. Furthermore, we conducted functional enrichment analysis of the 17 miRNA-targeted mRNAs, including the regulation of mTOR activity and cell autophagy, Th1/Th2 cell balance and immunoregulation, cell apoptosis, and so on. In summary, our study identified and validated a 17-miRNA diagnostic signature with convincing AUC, sensitivity, and specificity for periodontitis.

Periodontitis is associated with hypertension: a systematic review and meta-analysis

Recent evidence suggests a link between periodontitis (PD) and hypertension, but the nature of this association remains unclear. The overall aim of this review was to critically appraise the evidence linking these two common disorders. Systematic search was conducted for studies published up to December 2018. Prevalence of hypertension in patients with PD (moderate/severe groups) vs. those without PD (non-PD) was the primary outcome. Additional outcomes included adjusted mean difference in systolic (SBP) and diastolic (DBP) blood pressure (BP) levels in PD vs. non-PD, assessment of biomarkers in PD and hypertension, and BP changes after periodontal therapy. From 81 studies selected, 40 were included in quantitative meta-analyses. Diagnoses of moderate-severe PD [odds ratio (OR) = 1.22; 95% confidence interval (CI): 1.10-1.35] and severe PD (OR = 1.49; 95% CI: 1.09-2.05) were associated with hypertension. Prospective studies confirmed PD diagnosis increased likelihood of hypertension occurrence (OR = 1.68; 95% CI: 0.85-3.35). Patients with PD exhibited higher mean SBP [weighted mean difference (WMD) of 4.49 mmHg; 95% CI: 2.88-6.11] and DBP (2.03 mmHg; 95% CI: 1.25-2.81) when compared with non-PD. Lastly, only 5 out of 12 interventional studies confirmed a reduction in BP following periodontal therapy, ranging from 3 to 12.5 mmHg of SBP and from 0 to 10 mmHg of DBP. PD is associated with increased odds of hypertension (SORT C) and higher SBP/DBP levels. The evidence suggesting that PD therapy could reduce BP is inconclusive. Although additional research is warranted on this association, these results suggest that oral health assessment and management of PD could not only improve oral/overall health and quality of life but also be of relevance in the management of patients with hypertension.

Impact of history of periodontitis on gene expression of bone-related factors in young patients

Although dental implants and bone regenerative procedures are important approaches for the reestablishment of esthetics and function in young patients with a history of generalized aggressive periodontitis (GAP), no predictable outcomes have been reported, and the host osteo-immunoinflammatory response may play a relevant role in this context. In view of the lack of molecular investigations into the bone tissue condition of young patients with periodontitis, the aim of this study was to evaluate the gene expression of bone-related factors in this population. Bone biopsies were obtained from the posterior mandible in 16 individuals previously diagnosed with GAP and on periodontal support therapy and from 17 periodontally healthy (PH) patients. The gene expression of tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β, receptor activator of the NF-κB ligand (RANKL), osteoprotegerin (OPG), osteocalcin (OC), bone sialoprotein (BSP), and type I collagen (COL-I), important biomarkers of bone turnover, was evaluated by qRT-PCR. Lower TGF-β and OPG mRNA levels were observed in GAP patients compared to PH individuals (p ≤ 0.05). There were no between-group differences in levels of TNF-α, BSP, RANKL, OC, or COL-I mRNA (p>0.05). In young adults, a history of periodontal disease can negatively modulate the gene expression of important bone-related factors in alveolar bone tissue. These molecular outcomes may contribute to the future development of therapeutic approaches to benefit bone healing in young patients with history of periodontitis via modulation of osteo-immuno-inflammatory biomarkers.

Efficacy of regenerative therapy in aggressive periodontitis: a systematic review and meta-analysis of randomised controlled clinical trials

OBJECTIVES

To analyse evidence regarding the efficacy of periodontal regenerative procedures in intrabony defects in patients treated for aggressive periodontitis (AgP).

MATERIAL AND METHODS

A systematic search of the literature for randomised controlled clinical trials including patients treated for aggressive periodontitis that compared a group treated with regenerative therapy with another group treated with surgical debridement alone was conducted by two independent reviewers.

RESULTS

Six studies were included in the meta-analysis of clinical and/or radiographic parameters at 6 and 12 months. Probing pocket depth was smaller at 6 months in patients treated with regenerative therapies compared with those treated with regular debridement (1.00 mm, p < 0.001, 95% CI (0.67, 1.34)). At 12 months this difference was more marked (0.41 mm, p = 0.12, 95% CI (- 0.10, 0.91)). The distance between the cemento-enamel junction and the alveolar crest at both 6 (1.36 mm, p < 0.001, 95% CI (1.03, 1.68)) and 12 months (0.90 mm, p = 0.01, 95% CI (0.24, 1.56)) was smaller in the group treated with regeneration.

CONCLUSIONS

The use of biomaterials for regenerative therapy in AgP may be more effective than surgical debridement. Better outcomes were observed in terms of probing pocket depth and distance between the cemento-enamel junction and the alveolar crest at 6 months. Regeneration should be considered as a therapy to prevent tooth loss, although more studies with larger sample size and longer follow-up are needed.

CLINICAL RELEVANCE

Periodontal regeneration is effective in the treatment of intrabony defects in patients with AgP, as it leads to better outcomes in clinical and radiographic parameters.

Unique etiologic, demographic, and pathologic characteristics of localized aggressive periodontitis support classification as a distinct subcategory of periodontitis

BACKGROUND

Localized aggressive periodontitis (LAgP) occurs in 2% of African-American adolescents but only 0.15% of white adolescents. First molars and incisors are affected by rapid onset and progression.

METHODS

This nonsystematic critical review evaluated published data for LAgP and chronic periodontitis (CP), focusing on potential differences in epidemiology, microbiology, immunology, genetics, and response to therapy.

RESULTS

LAgP differs from CP by localization to incisors and first molars, early onset and rapid progression in adolescents and young adults, and a 10-fold higher prevalence in populations of African or Middle Eastern origin, often with strong familial aggregation. The bacterium Aggregatibacter actinomycetemcomitans and hyperresponsive neutrophils are frequently observed. Antibiotic and nonsurgical therapies are highly effective.

CONCLUSIONS

LAgP differs in many ways from the far more common CP that affects older adults. The substantial evidence of dissimilarities summarized in this review strongly supports the classification of LAgP as a distinct form of periodontitis.

PRACTICAL IMPLICATIONS

Classifying LAgP as a distinct subcategory of periodontitis will encourage future research and does not conflict with the newly proposed "staging and grading" system. The silent onset and rapid progression of LAgP make early diagnosis and frequent follow-up with patients essential for effective treatment.

Repeated application of photodynamic and antibiotic therapy as an adjunct to root surface debridement in patients with grade C and stage III or IV aggressive periodontitis

PURPOSE

To evaluate the efficacy of antimicrobial photodynamic therapy (aPDT) and antimicrobial therapy on clinical and immunological outcomes of periodontal treatment in patients with periodontitis grade C and stage III or IV.

MATERIAL AND METHOD

The patients recruited in the current research fulfil the clinical case definition of periodontitis 'grade C' in terms of onset of the infection and stage III or IV that defines degree and severity of the disease. One-stage full-mouth ultrasonic debridement (UD) was performed and randomly divided in two groups: Group-I - four applications of aPDT, and Group-II - combination of metronidazole (MTZ) and amoxicillin (AMX) 3 tablets each for 7 days. Whole-mouth periodontal parameters were recorded at baseline, 3-, 6-months after completion of treatment. Gingival crevicular fluid samples were obtained for assessment of inflammatory interleukin (IL)-10 and IL-17 at the same time points.

RESULTS

Seventeen healthy patients completed the study protocol and revealed similar clinical findings at baseline. Bleeding scores significantly reduced in group-I at 3 months post treatment (p < 0.05). It could be seen that group-I showed statistically significant reduction of deep periodontal pockets and gain in CAL in patients with GAP at 3 months (p < 0.05). This difference was maintained at 6 months of follow-up (p < 0.001). Group-II was capable of increasing the levels of IL-10 and reducing IL-17 in GCF at both time periods compared to Group-I (p < 0.05). Group-I did not have significant effect on either cytokine levels in GCF (p > 0.05).

CONCLUSION

Antimicrobial photodynamic therapy improved severe deep periodontal pockets. However, the combination of antimicrobial therapy helped in reducing proinflammation in grade C and stage III or IV periodontitis.

Association between the IL-10 rs1800872 polymorphisms and periodontitis susceptibility: A meta-analysis

BACKGROUND

Periodontitis is a common disease with an unclear pathological mechanism. No precise consensus has been reached to evaluate the association between the IL-10 rs1800872 (- 592, -590, -597 C>A) polymorphism and periodontal disease. Thus, we performed this meta-analysis to collect more evidence-based information.

METHODS

Four online databases, PubMed, Embase, Web of Science, and China Biology Medicine disc (CBM), were searched in August 2018. An odds ratio (OR) with a 95% confidence interval (CI) was applied to evaluate the association of the rs1800872 with periodontitis susceptibility.

RESULTS

Twenty three case-control studies with 2714 patients and 2373 healthy controls were evaluated. The overall analyses verified that the IL-10 rs1800872 polymorphism was significantly associated with an increased risk of periodontitis in the allelic model, homozygote model, dominant model, and recessive model (A vs C: OR = 1.28, 95%CI = 1.11-1.49, P = .00, I = 56.87%; AA vs CC: OR = 2.06, 95%CI = 1.32-3.23, P = .00, I = 73.3%; AA + AC vs CC: OR = 1.42, 95%CI = 1.03-1.96, P = .03, I = 76.2%; AA vs AC + CC: OR = 1.78, 95%CI = 1.26-2.56, P = .00, I = 76.7%). Moreover, the subgroup analysis based on ethnicity, periodontitis type, and smoking status showed significant differences.

CONCLUSIONS

The results of our meta-analysis demonstrate that rs1800872 is associated with periodontitis susceptibility in Caucasians and Asians. Moreover, A allele, AA genotype, CC genotype may be closely associated with chronic periodontitis (CP), while A allele, AA genotype may be closely associated with aggressive periodontitis (AgP).

The socioeconomic impact of Korean dental health insurance policy on the elderly: a nationwide cohort study in South Korea

Purpose

The purpose of this retrospective study was to investigate the relationships of types of dental insurance coverage in Korea with sociodemographic characteristics and the prevalence of systemic and oral diseases, as well as to evaluate the socioeconomic impact of Korean dental insurance policies.

Methods

Sample cohort data from 2006 to 2015 were obtained from the National Health Insurance Service. Patients were divided into 2 groups. The exposed group comprised patients who received insurance benefits for complete dentures, removable partial dentures, and implant care, while the control group comprised patients who did not receive these benefits. The type of insurance coverage and the prevalence of systemic and oral diseases were compared between the 2 groups.

Results

Patients who received benefits in the form of complete dentures, removable partial dentures, and implants had similar sociodemographic characteristics in terms of sex, age, income quintile, and type of insurance coverage to the control group. The prevalence of hypertension, anemia, renal disease, rheumatoid arthritis, osteoporosis, asthma, and cerebral infarction was higher in the exposed group than in the control group (P<0.05). The prevalence of periodontal diseases and dental caries was also higher in the exposed group.

Conclusions

Korean dental health insurance policy has been beneficial for the medical expenses of low-income and elderly people suffering from a cost burden due to systemic diseases. However, since there is a tendency to avoid invasive interventions in older patients due to the high risk of systemic diseases, insurance coverage of dentures may be more helpful from a socioeconomic perspective than coverage of dental implant treatments.

Periodontal disease in a young Romanian convenience sample: radiographic assessment

Background

The goal of this study was to determine the distribution of periodontal disease in a population seeking oral rehabilitation in a Romanian prosthodontics department and to identify the factors associated with each type of periodontal condition.

Methods

The study population consisted of patients presenting consecutively to the Prosthodontics Department of the Faculty of Dental Medicine, Victor Babeş University of Medicine and Pharmacy, Timisoara. The diagnosis and classification of periodontal conditions, as well as dental pathologies and conditions, were based on examination of panoramic radiographs. A standardized questionnaire was administered to obtain socio-demographic characteristics (age, gender, ethnicity, education, residency, marital status), medical history, dental/periodontal history (family history of periodontal disease), and behavior (smoking, brushing, flossing and regular cleaning).

Results

Among subjects presenting to the Prosthodontics department, only 34.2% were periodontal disease-free and 65.8% had periodontal disease, of which 11.4% had aggressive periodontitis. In univariate models, age, education, marital status, smoking, and tooth number were associated with chronic periodontitis. Age, education, family history, smoking, and tooth number were associated with aggressive periodontitis. However, in a multivariable model, only age, tooth number and family history were significant.

Conclusions

This study found a high prevalence of periodontal disease in patients seeking oral rehabilitation from the Prosthodontics department. Age, tooth number and family history of periodontal disease were associated with the type of periodontal disease. These results suggest the need for periodontal examination prior to prosthetic oral rehabilitation in this population.

Predictors for tooth loss in periodontitis patients: Systematic review and meta-analysis

AIM

A range of predictors for tooth loss in periodontitis patients have been reported. We performed a systematic review and meta-analysis to assess the consistency and magnitude of any association between a total of 12 predictors and tooth loss.

MATERIALS AND METHODS

Medline/Embase/Central were searched for longitudinal studies investigating the association between predictors and tooth loss in periodontitis patients. Random-effects meta-analysis was performed, and study quality assessed.

RESULTS

Twenty studies (15,422 patients, mean follow-up: 12 years) were included. The mean annual tooth loss/patient was 0.12 (min./max: 0.01/0.36). Older patients (n = 8 studies; OR: 1.05, 95% CI: 1.03-1.08/year), non-compliant ones (n = 11; 1.51, 1.06-2.16), diabetics (n = 7; 1.80, 1.26-2.57), those with IL-1-polymorphism (n = 3; 1.80; 1.29-2.52) and smokers (n = 15; 1.98, 1.58-2.48) had a significantly higher risk of tooth loss. Teeth with bone loss (n = 3; 1.04, 1.03-1.05/%), high probing pocket depth (n = 6; 3.19, 1.70-5.98), mobility (n = 4; 3.71, 1.65-8.38) and molars (n = 4; 4.22, 2.12-8.39), especially with furcation involvement (n = 5; 2.68, 1.75-4.08) also showed higher risks. Gender (n = 16; 0.95, 0.86-1.05) and endodontic affection (n = 3; 3.62, 0.99-13.2) were not significantly associated with tooth loss.

CONCLUSIONS

Older, non-compliant, smoking or diabetic patients, and teeth with bone loss, high probing pocket depth, mobility, or molars, especially with furcation involvement showed higher risks of tooth loss.

Regeneration of the Periodontal Apparatus in Aggressive Periodontitis Patients

The purpose of this study is to evaluate and compare, retrospectively, the outcome of two different periodontal regeneration procedures in patients suffering from aggressive periodontitis (AgP). Twenty-eight patients were diagnosed with AgP, suffering from several intra-bony defects (IBD); that were treated by one of two periodontal regeneration techniques randomly assigned to each patient: a. guided tissue regeneration (GTR) or b. an application of extracted enamel matrix derivatives (EMD) combined with demineralized bone xenograft particles (DBX). Probing pocket depth (PPD), clinical attachment level (CAL), and gingival recession were recorded. Pre-treatment and follow-up (up to 10 years from the surgery) recordings were analyzed statistically within and between groups. A significant reduction was shown at time on PPD and CAL values, however, not between subject groups. CAL values decreased in all sites. At the EMD group (44 sites), CAL gain was 1.92 mm (±1.68) from pre-treatment to follow-up (p < 0.001) and at the GTR group (12 sites) CAL gain of 2.27 (±1.82) mm. In conclusion, 1⁻10 years observations have shown that surgical treatment of AgP patients by either GTR or by application of EMD/DBX results in similar successful clinical results.

Long noncoding RNA LINC00707 sponges miR-370-3p to promote osteogenesis of human bone marrow-derived mesenchymal stem cells through upregulating WNT2B

BACKGROUND

Human bone marrow-derived mesenchymal stem cells (HBMSCs) are characterized by multiple differentiation potential and potent self-renewal ability, yet much remains to be elucidated on what determines these properties. Long-chain noncoding RNAs (lncRNAs) have been suggested to be involved in multiple biological processes under physiological and pathological conditions, including osteogenic differentiation.

METHODS

Alkaline phosphatase (ALP) activity assay, ALP staining, and Alizarin Red Staining were used for osteogenic potential detection. Western blot and qRT-PCR were used to examine the expression of LINC00707 and miR-370-3p. RNA-binding protein immunoprecipitation was used to detect the interaction between LINC00707 and RNA-induced silencing complex. Luciferase reporter assay was used to confirm the binding sites of miR-370-3p to LINC00707 and WNT2B.

RESULTS

We demonstrated that LINC00707 expression was gradually increased in HBMSCs during consecutive osteogenic induction, and it could further positively regulate the osteogenic differentiation both in vitro and in vivo, whereas LINC00707 inhibition led to suppressed osteogenic differentiation. Thereafter, we inferred a predicted interaction between LINC00707 and miR-370-3p and then confirmed the direct binding sites of miR-370-3p on LINC00707. While miR-370-3p upregulation led to decreased osteogenic differentiation, LINC00707 overexpression could reverse this suppression, indicating that LINC00707 acts as a competing endogenous RNA (ceRNA) for miR-370-3p. Moreover, LINC00707 could act as a ceRNA to upregulate WNT2B via miR-370-3p inhibition.

CONCLUSIONS

In conclusion, our study provides a novel lncRNA-miRNA regulatory network and a promising target to modulate the osteogenic differentiation of HBMSCs.

Predictive factors for tooth loss during supportive periodontal therapy in patients with severe periodontitis: a Japanese multicenter study

Background

Supportive periodontal therapy (SPT) must take individual patient risk factors into account. We conducted a multicenter joint retrospective cohort study to investigate the value of modified periodontal risk assessment (MPRA) and therapy-resistant periodontitis (TRP) assessment as predictive factors for tooth loss due to periodontal disease in patients with severe periodontitis during SPT.

Methods

The subjects were 82 patients from 11 dental institutions who were diagnosed with severe periodontitis and continued SPT for at least 1 year (mean follow-up = 4.9 years) between 1981 and 2008. The outcome was tooth loss due to periodontal disease during SPT. The Cox proportional hazards model was used to analyze sex, age, diabetes status, smoking history, number of periodontal pockets measuring ≥6 mm, rate of bleeding on probing, bone loss/age ratio, number of teeth lost, MPRA, and TRP assessment as explanatory variables.

Results

Univariate analysis showed that loss of ≥8 teeth by the start of SPT [hazard ratio (HR) 2.86], MPRA score indicating moderate risk (HR 8.73) or high risk (HR 11.04), and TRP assessment as poor responsiveness to treatment (HR 2.79) were significantly associated with tooth loss (p < 0.05). In a model in which the explanatory variables of an association that was statistically significant were added simultaneously, the HR for poor responsiveness to treatment and ≥8 teeth lost was significant at 20.17 compared with patients whose TRP assessment indicated that they responded favorably to treatment and who had lost <8 teeth by the start of SPT.

Conclusion

MPRA and TRP assessment may be useful predictive factors for tooth loss due to periodontal disease during SPT in Japanese patients with severe periodontitis. Additionally, considering the number of teeth lost by the start of SPT in TRP assessment may improve its predictive accuracy.

Effect of total sonicated Aggregatibacter actinomycetemcomitans fragments on gingival stem/progenitor cells

Background

Aggregatibacter-actinomycetemcomitans (A.actinomycetemcomitans) are strongly associated with localized-aggressive-periodontitis (LAgP). The study’s aim was to test for the first time the effect of total sonicated A.actinomycetemcomitans-bacterial-fragments on gingival mesenchymal stem/progenitor cells’ (G-MSCs) proliferation and regenerative gene expression in-vitro.

Material and Methods

G-MSCs were isolated, characterized, expanded and stimulated by total sonicated A.actinomycetemcomitans-bacterial-fragments (0 (negative-control), 15, 60, 120 and 240µg/ml; serovar-b; n=6/group). Cellular proliferation and NF-κβ (NFKB1), Alkaline Phosphatase (ALPL), Collagen-I (COL1A1), Collagen-III (COL3A1), Osteonectin (SPARC) and Osteopontin (SPP1) m-RNA expression were assessed via reverse-transcription-polymerase-chain-reaction (RT-PCR) at 24, 48 and 72 hours and CFUs-ability evaluated at twelve days.

Results

G-MSCs demonstrated stem/progenitor cells’ characteristics. A.actinomycetemcomitans-bacterial-fragments (up to 72 hours) resulted in marked G-MSCs’ proliferation over-time (p<0.001) and elevated NFKB1 (p=0.017), COL1A1 (p=0.025), SPARC (p=0.025), decreased ALPL (p=0.017), with no significant differences for COL3A1 and SPP1 expression or stimulation times (p>0.05; Friedman-test). Longer-term stimulation for twelve days reduced G-MSCs’ CFUs.

Conclusions

Sonicated A.actinomycetemcomitans-bacterial-fragments’ exert beneficial short-term effects on G-MSCs’ proliferative and non-mineralized tissue forming aptitude. Results shed new light on the importance of periodontal treatment for LAgP patients, using power driven sonic/ultrasonic devices, which, in addition to reducing the subgingival microbial load, produces cell-stimulatory A.actinomycetemcomitans-bacterial-fragments, with positive attributes on tissue reparative/regenerative responses of tissue resident stem/progenitor cells in their niche.

Key words:Ultrasonic, Aggregatibacter actinomycetemcomitans, stem cells, gingiva, Aggressive periodontitis.

Clinical performance of non-surgical periodontal therapy in a large Chinese population with generalized aggressive periodontitis

AIM

This study aimed to evaluate clinical performance of non-surgical periodontal treatment (NSPT) and its influential factors in a large Chinese population with generalized aggressive periodontitis (GAgP).

MATERIAL AND METHODS

Longitudinal periodontal examination data of 1,004 GAgP patients (numbers of patients with observation periods 6 weeks~, 3 months~, 6 months~, 1 year~, 3 years~ and >5 years were 203, 310, 193, 205, 70 and 23, respectively) were extracted from a hospital-based electronic periodontal charting record system and analysed by multilevel analysis.

RESULTS

Mean probing depth (PD) and attachment loss (AL) reductions at patient level were 1.17 mm and 1.07 mm, respectively. Multilevel analysis demonstrated PD reductions after maintenance were mainly influenced by frequency of supportive periodontal treatment (FSPT), gender, adjunctive systemic use of antibiotics, baseline mobility, tooth type and baseline PD and bleeding index reductions were mainly influenced by FSPT, adjunctive systemic use of antibiotics, baseline AL, baseline mobility, tooth type and baseline PD.

CONCLUSION

The clinical performance of NSPT on patients with GAgP was proved in the large Chinese population. Outcomes of NSPT were mainly influenced by FSPT, adjunctive systemic use of antibiotics, baseline mobility, tooth type and baseline PD.

Host-defense peptides and their potential use as biomarkers in human diseases

Since the early 19th century, host-defense peptides (HDPs) have been known to play a crucial role in innate host defense. Subsequent work has demonstrated their role in adaptive immunity as well as their involvement in cancer and also a number of inflammatory and/or autoimmune diseases. In addition to these multiple functional activities, several studies have shown that HDP accumulation might be correlated with various human diseases and, therefore, could be used as a biomarkers for such. Thus, research has aimed to validate the clinical use of HDPs for diagnosis, prognosis, and further treatment. In this review, we outline the most recent findings related to the use of HDPs as biomarkers, their clinical and epidemiological value, and the techniques used to determine the levels of HDPs.

The Effects of Antimicrobial Peptide Nal-P-113 on Inhibiting Periodontal Pathogens and Improving Periodontal Status

Periodontal disease consists of chronic gingival inflammation characterized by both degradation of the periodontal connective tissue and alveolar bone loss. Drug therapy is used as an auxiliary treatment method in severe chronic periodontitis, aggressive periodontitis, and periodontitis-associated systemic disease. Nal-P-113, a modified antimicrobial peptide, specifically replaces the histidine residues of P-113 with the bulky amino acid β-naphthylalanine, and our previous studies have verified that this novel peptide is not toxic to the human body within a certain concentration range. The objective of the present study was to evaluate the effect of Nal-P-113 on periodontal pathogens and periodontal status in clinical studies. In a split-mouth clinical trial, the pocket depth and bleeding index values tended to decrease in the experimental group compared with those in the control group. SEM results verified that Nal-P-113 restrained the maturation of plaque. Based on real-time polymerase chain reaction, the levels of Fusobacterium nucleatum, Streptococcus gordonii, Treponema denticola, and Porphyromonas gingivalis in subgingival plaque were decreased when the subjects were given Nal-P-113. Bacterial growth curve analysis and a biofilm susceptibility assay verified that Nal-P-113 at a concentration of 20 μg/mL restrained the growth of S. gordonii, F. nucleatum, and P. gingivalis and biofilm formation. Therefore, Nal-P-113 effectively reduces periodontal pathogens and ameliorates periodontal status.

Autoimmune Diseases and Oral Health: 30-Year Follow-Up of a Swedish Cohort

Oral infections up-regulate a number of systemic inflammatory reactions that, in turn, play a role in the development of systemic diseases. We investigated the association between oral health and autoimmune diseases in a cohort of Swedish adults. Hypothesis was that poor oral health associates with incidence of autoimmune diseases. Overall 1676 subjects aged 30–40 years old from Stockholm County (Sweden) participated in this study in 1985. Subjects were randomly selected from the registry file of Stockholm region and were followed-up for 30 years. Their hospital and open health care admissions (World Health Organization ICD 9 and 10 codes) were recorded from the Swedish national health registers. The association between the diagnosed autoimmune disease and the oral health variables were statistically analyzed. In all, 50 patients with autoimmune diagnoses were detected from the data. Plaque index was significantly higher in the autoimmune disease group (≥median 35 (70%) vs. ˂median 872 (54%), p = 0.030). No statistical difference was found in gingival index, calculus index, missing teeth, periodontal pockets, smoking or snuff use between patients with and without autoimmune disease. Our study hypothesis was partly confirmed. The result showed that subjects with a higher plaque index, marker of poor oral hygiene, were more likely to develop autoimmune diseases in 30 years.

Treatment of Localized Aggressive Periodontitis With Guided Tissue Regeneration Technique and Enamel Matrix Derivative

INTRODUCTION

Aggressive periodontitis (AgP) is a form of periodontitis characterized by rapid attachment loss in otherwise healthy individuals. Although different treatment options have been explored for management of the disease, control of disease progression and subsequent regeneration of the attachment apparatus are considered the ideal treatment objectives. Limited evidence is available with respect to the efficacy of different regenerative materials in the treatment of AgP.

CASE PRESENTATION

The present case report describes periodontal regeneration techniques and 6-month outcomes in bilateral intrabony non-contained defects around mandibular first molars in a 21-year-old patient diagnosed with localized AgP (LAgP). Periodontal lesions were treated with regenerative therapy with enamel matrix derivative (EMD) and allograft on the right side and allograft with bioabsorbable collagen membrane without EMD on the left side. Treatment yielded favorable clinical outcomes in terms of probing depth reduction, clinical attachment level gain, minimal gingival inflammation, and radiographic bone fill. Radiographic bone fill was observed after 6 months, suggesting possible periodontal regeneration.

CONCLUSION

Both regeneration techniques used in this clinical report (guided tissue regeneration involving allograft and bioabsorbable membrane versus EMD combined with allograft without a barrier membrane) resulted in favorable outcomes in the treatment of deep (≥7 mm) non-contained intrabony defects in LAgP.

Periodontal maintenance following active specialist treatment: Should patients stay put or return to primary dental care for continuing care? A comparison of outcomes based on the literature

OBJECTIVES

To review the evidence for the efficacy of periodontal maintenance (PM) carried out in primary dental care (PDC) compared to the specialist setting for patients previously treated in a specialist setting for chronic (ChP) or aggressive (AgP) periodontitis.

METHODS

A focused PICO question and search protocol were developed. Online databases including MEDLINE, EMBASE, WEB OF SCIENCE™ and COCHRANE LIBRARY were searched along with specialist journals in the subject area of periodontal research. Selection criteria included studies that investigated delivery of PM in both specialist and PDC settings for patients with ChP or AgP over a minimum 12 months. We looked for studies that reported changes in clinical attachment levels (CAL), tooth loss, pocket probing depths (PPDs) and bleeding on probing (BoP) as outcome measures.

RESULTS

Eight cohort studies were chosen for inclusion. There was considerable heterogeneity found between the eight studies, which did not allow for quantitative (meta) analysis and statistical testing of differences between groups. Clinical attachment levels remained relatively stable in patients who received specialist PM with mean changes of -0.42 mm to +0.2 mm, while for those enrolled in PDC-based PM for periods >12 months, mean CAL losses were between -0.13 mm and -2.80 mm. PPD reduction for those subjects receiving specialist PM was between 0.05 and 1.8 mm for five studies but two cohorts experienced increases of 0.32 and 0.80 mm, respectively. Increases of up to 2.90 mm (range: -0.1 to +2.90) and a higher proportion of deeper pockets were noted among PDC PM cohorts. Higher rates of BoP among those in receipt of PDC PM were reported in half of all studies. There were insufficient long-term data to make any firm conclusions about the effect of the delivery of PM on tooth loss.

CONCLUSION

Within the limitations of the data available, it appears that specialist PM is effective in sustaining periodontal stability following active specialist intervention. There is limited evidence that PDC provides the same level of care; however, the limited comparative data available suggest that outcomes could be slightly worse in PDC.

Diagnosis and Management of Chronic and Aggressive Periodontitis Part 2: Periodontal Management

The first paper of this three-part series discussed periodontal disease pathogenesis and highlighted elements in the clinical assessment which will help the clinician to establish the diagnosis of chronic and aggressive periodontitis. This second paper will focus on the management of chronic and aggressive periodontitis. Finally, the diagnosis and management of chronic and aggressive periodontitis will be reviewed in the third part of the series using two clinical examples. Clinical relevance: This paper aims to provide the general dental practitioner with an understanding of the aim of periodontal treatment, the management of chronic and aggressive periodontitis and the prognosis of periodontally involved teeth.

Long-term clinical response to treatment and maintenance of localized aggressive periodontitis: a cohort study

AIM

To evaluate long-term clinical response to periodontal therapy and maintenance in localized aggressive periodontitis (LAP).

MATERIALS AND METHODS

One hundred forty-one African Americans diagnosed with LAP, aged 5-25 years, were enrolled. Patients underwent periodontal mechanical debridement plus 1 week of amoxicillin/metronidazole. Mechanical therapy was repeated as needed and clinical parameters were recorded at baseline, 3, 6, 12, 18 and 24 months, and two additional annual follow-up visits after treatment. Radiographs from primary dentition of patients with LAP in permanent dentition, and additional healthy siblings (HS) were analysed retrospectively.

RESULTS

Periodontal therapy significantly improved probing depth and clinical attachment level up to 4 years (mean reductions: 2.18 ± 1.03 and 2.80 ± 1.43 mm, respectively). Percentage of affected sites was reduced at all time points and maintained up to 4 years. Non-compliance with antibiotics/appointments negatively affected the treatment response. Ninety per cent of LAP patients in permanent dentition and 32% of HS presented radiographic bone loss in primary dentition.

CONCLUSIONS

Mechanical debridement with 1 week of systemic antibiotics along with proper periodontal maintenance was effective in the treatment and successful maintenance of LAP for up to 4 years. LAP in permanent dentition may be preceded in the primary dentition. Clinicaltrials.gov #NCT01330719.

Regenerative effect of hOPG gene-modified autologous PDLs in combination with cell transplantation on periodontal defection in beagle dogs

This study evaluated the ability of human osteoprotegerin gene-modified autologous periodontal ligament cells (PDLCs) in combination with cell transplantation to promote periodontal regeneration in beagle dogs. Adenovirus Ad5-hOPG-EGFP-transfected PDLCs and BME-10X collagen membranes were fabricated and used for periodontal repair. Buccal periodontal defects (mesiodistal width × depth: 5 × 5 mm) were created on the second, third, and fourth mandibular premolars in six normal beagle dogs, and the defects were histologically and histomorphometrically assessed for periodontal regeneration in the following four groups: (1) hOPG-PDLCs + BME-10X, (2) mock-PDLCs + BME-10X, (3) PDLCs + BME-10X, and (4) BME-10X. The radiographic and histological results suggested that hOPG-PDLCs significantly promoted periodontal defect repair. This study demonstrates the potential of hOPG-modified PDLCs for periodontal tissue regeneration.

Sphingomyelin Phosphodiesterase 3 Enhances Cytodifferentiation of Periodontal Ligament Cells

Sphingomyelin phosphodiesterase 3 ( Smpd3), which encodes neutral sphingomyelinase 2 (nSMase2), is a key molecule for skeletal development as well as for the cytodifferentiation of odontoblasts and alveolar bone. However, the effects of nSMase2 on the cytodifferentiation of periodontal ligament (PDL) cells are still unclear. In this study, the authors analyzed the effects of Smpd3 on the cytodifferentiation of human PDL (HPDL) cells. The authors found that Smpd3 increases the mRNA expression of calcification-related genes, such as alkaline phosphatase (ALPase), type I collagen, osteopontin, Osterix (Osx), and runt-related transcription factor (Runx)-2 in HPDL cells. In contrast, GW4869, an inhibitor of nSMase2, clearly decreased the mRNA expression of ALPase, type I collagen, and osteocalcin in HPDL cells, suggesting that Smpd3 enhances HPDL cytodifferentiation. Next, the authors used exome sequencing to evaluate the genetic variants of Smpd3 in a Japanese population with aggressive periodontitis (AgP). Among 44 unrelated subjects, the authors identified a single nucleotide polymorphism (SNP), rs145616324, in Smpd3 as a putative genetic variant for AgP among Japanese people. Moreover, Smpd3 harboring this SNP did not increase the sphingomyelinase activity or mRNA expression of ALPase, type I collagen, osteopontin, Osx, or Runx2, suggesting that this SNP inhibits Smpd3 such that it has no effect on the cytodifferentiation of HPDL cells. These data suggest that Smpd3 plays a crucial role in maintaining the homeostasis of PDL tissue.

A Putative Association of a Single Nucleotide Polymorphism in GPR126 with Aggressive Periodontitis in a Japanese Population

Periodontitis is an inflammatory disease causing loss of tooth-supporting periodontal tissue. Disease susceptibility to the rapidly progressive form of periodontitis, aggressive periodontitis (AgP), appears to be influenced by genetic risk factors. To identify these in a Japanese population, we performed whole exome sequencing of 41 unrelated generalized or localized AgP patients. We found that AgP is putatively associated with single nucleotide polymorphism (SNP) rs536714306 in the G-protein coupled receptor 126 gene, GPR126 [c.3086 G>A (p.Arg1029Gln)]. Since GPR126 activates the cAMP/PKA signaling pathway, we performed cAMP ELISA analysis of cAMP concentrations, and found that rs536714306 impaired the signal transactivation of GPR126. Moreover, transfection of human periodontal ligament (HPDL) cells with wild-type or mutant GPR126 containing rs536714306 showed that wild-type GPR126 significantly increased the mRNA expression of bone sialoprotein, osteopontin, and Runx2 genes, while mutant GPR126 had no effect on the expression of these calcification-related genes. The increase in expression of these genes was through the GPR126-induced increase of bone morphogenic protein-2, inhibitor of DNA binding (ID) 2, and ID4 expression. These data indicate that GPR126 might be important in maintaining the homeostasis of periodontal ligament tissues through regulating the cytodifferentiation of HPDL cells. The GPR126 SNP rs536714306 negatively influences this homeostasis, leading to the development of AgP, suggesting that it is a candidate genetic risk factor for AgP in the Japanese population.

A Modified Glycosaminoglycan, GM-0111, Inhibits Molecular Signaling Involved in Periodontitis

Background

Periodontitis is characterized by microbial infection, inflammation, tissue breakdown, and accelerated loss of alveolar bone matrix. Treatment targeting these multiple stages of the disease provides ways to treat or prevent periodontitis. Certain glycosaminoglycans (GAGs) block multiple inflammatory mediators as well as suppress bacterial growth, suggesting that these GAGs may be exploited as a therapeutic for periodontitis.

Methods

We investigated the effects of a synthetic GAG, GM-0111, on various molecular events associated with periodontitis: growth of Porphyromonas gingivalis (P. gingivalis) and Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) pathogenic bacteria associated with periodontitis; activation of pro-inflammatory signaling through TLR2 and TLR4 in mouse macrophage RAW 264.7 cells and heterologously expressed HEK 293 cells; osteoclast formation and bone matrix resorption in cultured mouse pre-osteoclasts.

Results

(1) GM-0111 suppressed the growth of P. gingivalis and A. actinomycetemcomitans even at 1% (w/v) solution. The antibacterial effects of GM-0111 were stronger than hyaluronic acid (HA) or xylitol in P. gingivalis at all concentrations and comparable to xylitol in A. actinomycetemcomitans at ≥2% (w/v) solution. We also observed that GM-0111 suppressed biofilm formation of P. gingivalis and these effects were much stronger than HA. (2) GM-0111 inhibited TLR-mediated pro-inflammatory cellular signaling both in macrophage and HEK 293 cells with higher selectivity for TLR2 than TLR4 (IC₅₀ of 1–10 ng/mL vs. > 100 μg/mL, respectively). (3) GM-0111 blocked RANKL-induced osteoclast formation (as low as 300 ng/mL) and bone matrix resorption. While GM-0111 showed high affinity binding to RANKL, it did not interfere with RANKL/RANK/NF-κB signaling, suggesting that GM-0111 inhibits osteoclast formation by a RANKL-RANK-independent mechanism.

Conclusions

We report that GM-0111 inhibits multiple molecular events involved in periodontitis, spanning from the early pro-inflammatory TLR signaling, to pathways activated at the later stage component of bone loss.

Peri-implant and periodontal microbiome diversity in aggressive periodontitis patients: a pilot study

AIM

To investigate the bacterial microbiome in periodontal and peri-implant biofilms deriving from aggressive periodontitis patients (AgP) in conditions of health and disease.

MATERIAL AND METHODS

Ninety-one plaque samples were collected from 18 patients previously diagnosed and treated for AgP. The samples were taken from (i) 24 residual periodontal pockets (TD) (n = 6 patients), (ii) 24 healthy periodontal sites (TH) (n = 6 patients), (iii) 24 dental sites from the same implant patients (TM) (n = 6 patients), (iv) 5 peri-implantitis sites (II) (n = 2 patients), (v) 6 peri-mucositis sites (IM) (n = 2 patients) and (vi) 8 healthy implant sites (IH) (n = 2 patients). All subjects underwent periodontal clinical and radiographic assessments. Bacterial DNA was extracted, PCR amplified using 16S rRNA gene V5-V7 primers (barcoded amplicons 785F;1175R), purified, pooled at equimolar concentrations and sequenced (MiSeq, Illumina) yielding 250 bp paired-end reads. The 16S rRNA reads were filtered, assembled and analysed.

RESULTS

The genera Propionibacterium, Paludibacter, Staphylococcus, Filifactor, Mogibacterium, Bradyrhizobium and Acinetobacter were unique to peri-implant sites (P = 0.05). In TM samples, different proportions and bacterial spp. were found when compared with the same patients' samples at implant sites. Specifically, Actinomyces (P = 0.013) and Corynebacterium (P = 0.030) genera showed to be significantly more abundant in the TM group when compared to the II. The highest phylogenetic diversity was observed in residual periodontal pocket sites (TD). Increased annual tooth loss rate and residual pocketing was related to high proportions of the genera Actinomyces, Porphyromonas, Prevotella, Streptococcus, Actinomycetaceae, TM7-3, Selenomonas, and Dialister, Treponema, Parvimonas and Peptostreptococcus in the TD group.

CONCLUSION

Within the limitations of this pilot study, the periodontal and peri-implant microbiome presents a dissimilar taxonomic composition across different niches within AgP patients. The host response, the habitat structure and the vast coexistence of strains and species surrounding implants and teeth in health and disease are likely to be shaping the heterogeneous composition of the subgingival biofilms. The TM7 phylum was found only in TD cases. The investigation of the impact of periodontal and peri-implant keystone species on these complex ecosystems in states of health and disease seems to be essential.

Photodynamic therapy in the treatment of aggressive periodontitis: A systematic review

BACKGROUND

Aggressive periodontitis (AgP) is a severe form of periodontal diseases with rapid destruction of the supporting bone around teeth. The efficacy of PDT in suppressing periodontal pathogens may be crucial in adopting new protocols for the treatment of AgP. Thus, the aim of this systematic review was to investigate the possible role of PDT in the treatment of AgP as an adjunctive therapy or monotherapy.

MATERIAL AND METHODS

A systematic search of the literature was performed. Additionally, the references from all the selected full-text studies were searched for relevant articles. Two reviewers screened independently titles and abstracts or full text copies. Quality assessment of all the included studies was held.

RESULTS

Initial screening of electronic databases yielded 418 potentially relevant publications. After screening of the titles and full-text examination, five studies were included in the systematic review. Four publications evaluated the effects of PDT adjunctive to SRP in patients with AgP: two of them compared the clinical outcomes of SRP and PDT with a control group that received therapy with SRP and antibiotics (metronidazole and amoxicillin); two publications included SRP and PDT in the test group, and SRP alone in the control group. In one study, PDT was tested as a monotherapy compared with SRP alone.

CONCLUSIONS

Within the limitations of this review, PDT may exhibit a beneficial role in the therapy of aggressive periodontitis after repeated applications. In the future, more methodologically sound, long-term randomized clinical trials are needed to be conducted.