Effect of Periodontitis and Periodontal Therapy on Oral and Gut Microbiota.

Mounting evidence indicates that periodontitis-related oral bacteria may contribute to gut microbial dysbiosis. This clinical study aimed to explore the oral-gut microbial signatures associated with periodontitis and to longitudinally evaluate the effect of periodontal treatment on the oral and gut microbial composition. Stool and saliva samples from generalized stage III/IV periodontitis patients (n = 47) were collected and analyzed by 16S ribosomal RNA gene amplicon sequencing, before and 3 mo after steps I to II of periodontal therapy. Periodontally healthy matched subjects (n = 47) were used as controls. Principal component analysis was carried out to identify oral-gut microbial profiles between periodontitis patients at baseline and healthy subjects; periodontitis samples were longitudinally compared before and after treatment. ß-Diversity of gut microbial profiles of periodontitis patients before treatment significantly differed from healthy controls (P < 0.001). Periodontal therapy was associated with a significant change in gut microbiota (P < 0.001), with post-treatment microbial profiles similar to healthy volunteers. A higher abundance of Bacteroides, Faecalibacterium, Fusobacterium, and Lachnospiraceae was noted in fecal samples of periodontitis patients at baseline compared to healthy controls. In contrast, Lactobacillus was the only genus more abundant in the latter. Additionally, periodontal therapy led to a parallel reduction in the salivary carriage of periodontal pathobionts, as well as gut Bacteroides, Lachnoclostridium, Lachnospiraceae, Oscillospiraceae, and Ruminococcaceae, to levels similar to healthy controls. Collectively, discriminating oral-gut microbial signatures of periodontitis were found. Periodontal treatment both mitigated oral dysbiosis and altered gut microbial composition, signifying potential broader implications for gastrointestinal health and disease.

Periodontitis and COVID-19: Biological Mechanisms and Meta-analyses of Epidemiological Evidence.

Since the beginning of 2020, the entire global health care system has been severely challenged by the outbreak of coronavirus 2019 disease (COVID-19). Robust evidence has demonstrated a more severe course of COVID-19 in the presence of several comorbidities, such as cardiovascular diseases, diabetes mellitus, and obesity. Here, we critically appraise the recent research discoveries linking periodontitis to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and to severe COVID-19, with a special focus on the associated biological mechanisms and the available epidemiological evidence. SARS-CoV-2 main receptors and coreceptors (ACE2, TMPRSS2, furin, CD147) are overexpressed in periodontal tissues of periodontitis patients, with inflammation, periodontal pathogens, and damage-induced pyroptosis triggering a positive feedback loop. However, meta-analyses of epidemiological studies only indicated a nonstatistically significant tendency for an increased risk of SARS-CoV-2 infection in subjects with periodontitis (odds ratio [OR] = 1.69; 95% CI, 0.91-3.13, P = 0.09). Furthermore, periodontitis may worsen clinical COVID-19 courses through multiple direct and indirect pathways, including damage to lower airways due to aspiration of periodontal pathogens, exacerbation of the cytokine storm via the low-grade chronic systemic inflammation, and SARS-CoV-2 dissemination through the ulcerated gingival epithelium with consequent induced pulmonary vessels vasculopathy. Indeed, meta-analyses of epidemiological studies indicated that periodontitis subjects are more likely to experience a more severe course of COVID-19. Specifically, periodontitis was associated with a 4-fold increased odds of hospitalization (OR = 4.72; 95% CI, 1.11-20.03, P = 0.04), 6-fold of requiring assisted ventilation (OR = 6.24; 95% CI, 2.78-14.02, P = 0.00), and more than 7-fold of death due to COVID-19 complications (OR = 7.51; 95% CI, 2.16-26.10, P = 0.00). The breakthrough analyzed here emphasizes the relevance of the mouth-systemic connection as a target to mitigate the current COVID-19 emergency and the future predicted coronavirus pandemics.

Periodontitis and Accelerated Biological Aging: A Geroscience Approach.

As the whole world is epidemically aging, the burden of periodontitis and tooth loss is becoming a major health concern. Growing meta-epidemiological data implicate chronic systemic inflammation/infection due to periodontitis as an independent risk factor for aging-related diseases and mortality. However, because people age differently, chronological age is not a reliable marker of an individual's functional status. Recent advances in geroscience have shown that various biomarker signatures of biological aging are longitudinally associated with declined physical function, morbidity, and mortality due to major age-related diseases, including periodontitis. Here, we emphasize novel research developments bidirectionally linking periodontitis to accelerated biological aging. Using a composite biomarker age estimator, a striking increase in periodontitis and tooth loss was observed in subjects whose biological age at baseline was higher than their chronological age. Moreover, significantly shortened telomeres were encountered in populations affected by severe periodontitis. Second, we elucidate the cellular and molecular pillars of the aging process at the periodontal level. Accumulating evidence suggests that cellular senescence, stem cell exhaustion, and immunoaging are hallmarks of biological aging implicated in the impairment of periodontal homeostasis and the pathophysiology of periodontitis. Indeed, persistent bacteria-derived lipopolysaccharide stimulation influences cellular senescence in osteocytes, driving alveolar bone resorption. Moreover, inflammaging status induced by chronic hyperglycemia elevates the burden of senescent cells in gingival tissues, impairing their barrier function. Lastly, we reviewed a recent breakthrough in senotherapy to directly target the mechanisms of aging at the periodontal level. Physical exercise and intermittent fasting, together with natural compounds, senolytic drugs, and cell therapy, are increasingly being evaluated to rejuvenate the oral cavity. Following these innovations in geroscience, further advancements could provide oral clinicians the chance to intercept biological aging when still "subclinical" and set interventions for halting or delaying the trajectory toward aging-related diseases while patients are still chronologically young.

Increased early inflammatory response and osteoclastic activity in gingival tissues following conventional osseous resective surgery compared with the fibre retention technique: a pilot study.

BACKGROUND AND OBJECTIVE: The retention of suprabony connective fibres attached into the root cementum during fibre retention osseous resective surgery (FibReORS) results in a more conservative intrasurgical removal of bone, and limits further bone loss and patient morbidity during healing, compared with conventional osseous resective surgery (ORS). This may be a result of the protective effect of preserved connective tissue over the interproximal sites and the lower activation of the inflammatory mechanisms. Thus, the aim of this pilot study was to compare the expression of inflammatory and osteoclastic activity markers in gingival tissues following FibReORS and ORS in the early postsurgical phase. MATERIAL AND METHODS: Twenty-six posterior sextants requiring osseous resective surgery were selected in 13 patients with chronic periodontitis: 13 sextants were randomly assigned to ORS and 13 to FibReORS in a split-mouth design. Gingival biospies were collected during the surgical sessions and at suture removal. Tissue samples were analysed to evaluate the expression of proinflammatory and immunity regulatory mediators (interleukin-1α, C-X-C motif chemokine ligand 5, interferon-γ and tumour necrosis factor-α), cluster of differentiation 14 (CD14; a monocyte/macrophage marker) and TRAP (an osteoclast marker) using immunohistochemical, immunofluorescence and cytofluorimetric analyses, respectively. RESULTS: Postsurgery, a higher number of inflammatory cells and stronger expression of proinflammatory cytokines were observed in the epithelium and connective tissue of ORS gingival samples compared with FibReORS gingival samples (p < 0.001). This was accompanied by increased numbers of CD14-positive and TRAP-positive cells. CONCLUSION: Retention of the supracrestal connective fibres appears to reduce the postsurgical intensity of the host-mediated inflammatory response.

Unexpected resilience to experimental gingivitis of subepithelial connective tissue grafts in gingival recession defects: a clinical-molecular evaluation.

BACKGROUND AND OBJECTIVE: The subepithelial connective tissue graft (SCTG) is the most widely used procedure for the treatment of gingival recession defects. Little is known, however, as to whether the apposed gingival flaps are more predisposed to develop plaque-related inflammation compared to healthy sites. This has salient clinical implications, as the long-term results of root coverage will depend largely on the level of inflammation of the grafted tissue. METHODS: In the present split-mouth case-control study, clinical and biomolecular parameters were used to assess the level of inflammation of periodontal sites 12 mo after treatment with SCTG (test) and healthy non-treated gingivae (control) following the induction of plaque-related gingivitis in 19 patients. RESULTS: The data showed that test sites had a significantly (P < 0.05) lower gingival index and angulated bleeding score compared to control sites (gingival index = 1.05 ± 0.23 vs. 1.34 ± 0.47; angulated bleeding score = 0.34 ± 0.37 vs. 0.61 ± 0.39) after induction of experimental gingivitis, whereas the plaque index did not differ in the two groups (P > 0.05). With regard to the biomolecular parameters, baseline levels of the proinflammatory cytokine interleukin-1ß were higher in the gingival crevicular fluid of test sites. However, control sites exhibited more pronounced increase in the levels of interleukin-1ß compared to test sites, upon plaque accumulation, so that the final concentration was similar in both groups. No changes were recorded in the gingival crevicular fluid volume. CONCLUSION: Analysis of the data demonstrates that the sites of gingival recession treated with SCTG develop a lower degree of plaque-induced inflammation compared to healthy gingivae. This strongly suggests that SCTG does not predispose to inflammation and to further gingival recession and makes it a safe technique in the treatment of gingival defects.

Healing properties of implants inserted concomitantly with anorganic bovine bone. A histomorphometric human study.

BACKGROUND: The present prospective, randomized, double-blind study evaluated the bone-forming process around implants inserted simultaneously with anorganic bovine bone (ABB) in sinus grafting. METHODS: A total of 18 threaded mini-implants with Osseotite (O) and Nanotite (N) surfaces were placed in seven patients (nine sites). After 12 months, the implants were retrieved and processed for histological analysis. A total of 18 cutting and grinding sections were investigated with bright-field light microscopy, circularly polarized light microscopy (CPLM), confocal scanning laser microscope (CSLM), and scanning electron microscope (SEM) with energy dispersive spectrometer (EDS). RESULTS: The bone-to-implant contact rate in native crestal bone was 62.6 ± 0.4% for N implants and 54.3 ± 0.5% for the O implants (p = 0.001). The collagen fibre density, as assessed by CPLM, was 79.8 ± 6.0 nm for the N group and 74.6 ± 4.6 nm for the O group (p < 0.05). Line scan EDS starting from ABB to newly formed bone showed a decrease in calcium content and an increase of carbon while phosphorus content was constant. CONCLUSIONS: While the N surface improved the peri-implant endosseous healing properties in the native bone, when compared to the O surface, it did not improve the healing properties in the bone-graft area.

Bone production by human maxillary sinus mucosa cells.

The Schneider membrane is the mucosa that covers the inner part of the maxillary sinus cavities. The free surface is a ciliated pseudostratified epithelium, while the deeper portion is a highly vascularized connective tissue. The stromal fraction, bordering the bony wall of the sinus, after tooth loss can exhibit increased osteoclastic activity resulting in resorption of the bone in the posterior maxilla. Goal of our study was to isolate and characterize mesenchymal progenitors in the Schneider's membrane connective net and to evaluate their self ability to differentiate toward osteoblastic lineage, in absence of osteoinductive factors and osteoconductive biomaterials of support. This should indicate that maxillary sinus membrane represents an useful an approachable source of MSCs for bone tissue engineering and cell therapy and owns the intrinsic capacity to restore maxillary bone after tooth loss without the needing of biomaterials.

Transglutaminase 2 expression is significantly increased in cyclosporine-induced gingival overgrowth.

Cyclosporine A is a potent immunosuppressant used to prevent organ transplant rejection and treat various autoimmune diseases. However, cyclosporine A can also induce gingival overgrowth, which is characterized by increased extracellular matrix due to an altered balance between collagen synthesis and degradation. This study proposed to verify whether trans-glutaminase 2, an enzyme thought to be responsible for the assembly and remodelling of extracellular matrix, plays any role in the pathogenesis of cyclosporine A-induced gingival overgrowth. Cyclosporine A-induced gingival overgrowths were collected from 21 liver transplant patients and case-controlled with 20 non-hyperplastic gingival biopsies from healthy patients who had previous periodontal treatment. In both groups, the presence and tissue distribution of transglutaminase 2 were determined by immunohistochemistry and analyzed in comparison with the tissue morphology and expression of lymphocyte-related antigens (CD3 and CD20) and a vessel-related marker (CD34). Transglutaminase 2 expression showed a significant increase (2.6-fold) in the stromal component of cyclosporine A-treated patients compared with controls (p<0.001), which suggested that transglutaminase 2 had a role in the pathogenesis of the disease. Further studies should investigate the therapeutic effect of anti-transglutaminase 2 drugs (putrescine or 1,4-diamino-butane) in these patients.

Gene--gene interaction among cytokine polymorphisms influence susceptibility to aggressive periodontitis.

Aggressive periodontitis (AgP) is a multifactorial disease. The distinctive aspect of periodontitis is that this disease must deal with a large number of genes interacting with one another and forming complex networks. Thus, it is reasonable to expect that gene-gene interaction may have a crucial role. Therefore, we carried out a pilot case-control study to identify the association of candidate epistatic interactions between genetic risk factors and susceptibility to AgP, by using both conventional parametric analyses and a higher order interactions model, based on the nonparametric Multifactor Dimensionality Reduction algorithm. We analyzed 122 AgP patients and 246 appropriate periodontally healthy individuals, and genotyped 28 polymorphisms, located within 14 candidate genes, chosen among the principal genetic variants pointed out from literature and having a role in inflammation and immunity. Our analyses provided significant evidence for gene--gene interactions in the development of AgP, in particular, present results: (a) indicate a possible role of two new polymorphisms, within SEPS1 and TNFRSF1B genes, in determining host individual susceptibility to AgP; (b) confirm the potential association between of IL-6 and Fc γ- receptor polymorphisms and the disease; (c) exclude an essential contribution of IL-1 cluster gene polymorphisms to AgP in our Caucasian-Italian population.

Merkel cells and permanent disesthesia in the oral mucosa after soft tissue grafts.

Connective tissue grafts are routinely procedures in the treatment of gingival defects. The clinical success of the gingival tissue graft procedures anyway should ensure not only the aesthetic integration between the tissues but also the physiological activity of the graft in terms of sensitivity and immunity because the skin and the mucosae constitute the first natural aspecific borders against pathogens. The aim of this paper was to investigate nervous net recovery after connective graft procedure, in relation with sensorial alteration in the injured area. Results showed that there is a close link among the number of Merkel cells and the alteration of sensations. Merkel cells can be found isolated standing in the basal layer, supposed to have neuroendocrine functions in the epithelia or in larger group not associated with nerves; when found in association with nerves they are named Merkel complexes, acting as slow adapter mechanical receptor. Our data can be explained in two ways: Merkel cells increase as a consequence of tissue injury, a sort of "SOS cells" that secrete neuroendocrine signals to guide tissue healing; as an alternative the presence of the Merkel cells could be read as a derailment of tissue regeneration with the stop of cellular differentiation in the direction of an abnormal proliferation, a sort of mad stem cell.

Patients' self-assessment of oral malodour and its relationship with organoleptic scores and oral conditions.

OBJECTIVES: The aim of this study was to compare patients' self-rating of oral malodour with organoleptic evaluation and to relate them to oral conditions. METHODS: One hundred and eighty systemically healthy patients with a primary complaint of oral malodour participated in this cross-sectional study. They were asked to complete a questionnaire regarding family and social discomfort and type of halitosis complaint, and to score the degree of their own oral malodour. The quality of the mouth air was assessed organoleptically by a calibrated odour judge. Odour-judge scores and self-assessments of bad breath were compared with one another as well as with clinical parameters (plaque index, bleeding index, probing depth and tongue coating score). RESULTS: The organoleptic test revealed that 93.9% of the subjects were found actually to have halitosis. The self-rating of oral malodour varied widely among patients. In 37.8% of patients, there was a correspondence between subjective and organoleptic measurements. The better correspondence was evident at 2-3 scores. The organoleptic ratings were significantly related to clinical parameters, whereas patients' self-measurements did not. The bleeding index had the highest correlation coefficient among the periodontal parameters examined (r = 0.665, P < 0.001). CONCLUSIONS: Self-estimation of bad breath correlated well with the presence of oral malodour as determined by organoleptic examination. Patients with slight or moderate oral halitosis presented the highest correlation rate between self- and odour-judge assessment.

Non-surgical periodontal treatment of cyclosporin A-induced gingival overgrowth: immunohistochemical results.

AIM: The present study was planned to analyze the effects of a 12-month non-surgical periodontal treatment on histologic and immunohistochemical features of cyclosporin A (CsA)-induced gingival overgrowth (GO). MATERIALS AND METHODS: Gingival samples were collected from 21 liver transplant subjects exhibiting CsA-induced GO prior to, and 12 months after non-surgical periodontal therapy including oral hygiene instructions, scaling and 2-month recall appointments, and also from 18 healthy control subjects. Gingival biopsy specimens were stained with hematoxylin-eosin and monoclonal antibodies for vimentin, CD3 (T-lymphocytes), CD20 (B-lymphocytes), CD34 (endothelium) and Ki-67 (fibroblasts proliferation rate), using a streptavidin-biotin-peroxidase complex method. RESULTS: Total inflammatory cells, gingival vessels and fibroblast proliferation rate demonstrated significant reduction after non-surgical periodontal treatment (P < 0.0001) in overgrown gingiva, while B- and T-lymphocytes remained nearly unchanged (P = 0.61 and 0.33, respectively). At the 12-month evaluation no significant differences were found when comparing the gingival biopsies from CsA-treated patients and those from healthy controls (P > 0.05). CONCLUSIONS: Control of clinical inflammation by means of non-surgical periodontal treatment results both in lowering of inflammatory infiltrate and in changes in connective tissue composition. Thus, plaque-induced inflammation would seem to modulate the drug-gingival tissue interaction. CLINICAL RELEVANCE: A strict plaque control program play a pivotal role in the management of transplant patients exhibiting cyclosporin A-GO.

Use of resorbable membranes in periodontal defects treatment after extraction of impacted mandibular third molars.

AIM: The aim of this study was to evaluate the efficacy of guided-tissue regeneration therapy (GTR) in the treatment of periodontal defects on the distal surface of mandibular second molars following surgical extraction of impacted third molars. METHODS: This split-mouth design study included 11 subjects who required extraction of bilateral impacted mandibular third molars and were at high risk for developing second molar periodontal defects after third molar extraction, that is mesioangular impaction and pre-existing periodontal defect (probing depth [PD] = or >5 mm) on the distal aspect of second molars. Within subjects, 1 postextraction site was randomly selected to receive scaling and root planing (SRP) of the distal surface of the second molar and the application of a polyglycolic acid/polylactic acid bioresorbable membrane (test site) and the opposite site served as control and was treated with SRP alone. The change in PD and clinical attachment level (CAL) as well as bone gain were assessed on the distal aspect of second molars over a 12-month period. RESULTS: Although both treatment modalities resulted in improvements in clinical parameters, the application of a bioresorbable membrane was statistical significantly more effective than SRP alone in reducing PD and in promoting CAL gain (P<0.0001). In 10 GTR-treated sites a complete bone fill was achieved, while 10 out of 11 control sites had residual intrabony defect. CONCLUSION: Subjects at high risk for developing second molar periodontal defects after third molar removal may benefit from the GTR-therapy at the time of surgical extraction of mesioangular impacted third molars to enhance periodontal healing.

Periodontal pathogens in periodontal pockets and in carotid atheromatous plaques.

AIM: In the last years the relationship between periodontitis and cardiovascular diseases has been a subject of increasing research. The identification of periodontopathic bacteria in atheromas can contribute to our knowledge of such an association. The aim of our study was to assess the concomitant presence of 5 periodontal pathogens (Actinobacillus actinomycetemcomitans, Prevotella intermedia, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia) in periodontal pockets and in carotid atheromas recovered from the same individuals. METHODS: Twenty-one patients with chronic periodontitis scheduled for endarterectomy for carotid stenosis were enrolled in the study. Subgingival plaque samples and carotid atheromas were examined using the polymerase chain reaction and reverse hybridization techniques by means of specific probes for periodontal bacteria. Human beta-globin amplification was used as internal polymerase chain reaction efficiency control. RESULTS: Three patients were excluded because the endarterectomy specimens were negative to DNA amplification. All subgingival plaque samples were positive for at least one target micro-organism. The prevalence of Tannerella forsythia, Porphyromonas gingivalis, Prevotella intermedia, Treponema denticola, and Actinobacillus actinomycetemcomitans was 72.22%, 61.11%, 55.56%, 50%, and 33.33%, respectively. No periodontal bacteria DNA was detected in any endarterectomy specimen. CONCLUSIONS: The presence of periodontal bacteria in atheromatous plaques was not confirmed by this investigation and, thus, no correlation between periodontitis bacteria and micro-organisms involved in the atherosclerotic lesions could be drawn.

Treatment of mandibular class II furcation defects by the use of amelogenins and autologous bone. Two case reports.

The aim of this preliminary study was to evaluate the clinical effectiveness of the association of amelogenins and autologous bone graft in the management of mandibular class II furcation defects. This randomized case-controlled study was conducted on 2 patients who presented 2 contralateral mandibular buccal class II furcation lesions. One defect was treated by amelogenins and autologous bone graft (test site) and the other one by open flap debridement (control site). At baseline and at 12 months postoperatively, the full-mouth plaque score (FMPS) and the full-mouth bleeding score (FMBS), the probing depth (PD), the clinical attachment level (CAL) and the recession (REC) were recorded and a periapical radiograph of the selected area was taken. In addition, at 12 months a surgical re-entry was performed. Test sites had a greater horizontal PD reduction and radiographic bone filling compared to control sites. None of the treated sites achieved complete furcation closure. At the time of re-entry, furcations treated by amelogenins were partially filled by newly formed not soundable hard tissue, while furcations treated by conventional flap surgery were filled by epithelial and connective tissue. These findings suggest that the treatment of mandibular class II furcations by amelogenins and autologous bone graft may result in a significant clinical improvement. Further long-term studies conducted on a larger sample size are therefore needed to confirm our results.

Treatment of wide, shallow, and predominantly 1-wall intrabony defects with a bioabsorbable membrane: a randomized controlled clinical trial.

BACKGROUND: The regenerative therapy of non-contained intrabony defects achieves better results when bioabsorbable membranes are combined with a filling material. The purpose of the present study was to analyze clinical and radiographic effectiveness of a space-making bioabsorbable membrane in the treatment of wide and shallow intrabony defects characterized by a relevant 1-wall component. METHODS: Eighteen pairs of angular bone defects were selected in 18 healthy, non-smoking patients (age range 30 to 66 years). Prior to the surgical phase, patients were enrolled in a strict periodontal program including oral hygiene instructions and scaling and root planing (presurgical full-mouth plaque score <10%). Using a split-mouth design, 18 sites were randomly assigned to receive guided tissue regeneration (GTR) using a bioabsorbable membrane (test group) and 18 to receive open flap debridement alone (control group). Clinical treatment outcome was evaluated 12 months postoperatively for changes in probing depth (PD), clinical attachment level (CAL), and position of gingival margin (REC) and radiographically for bone changes. RESULTS: Open flap debridement and GTR yielded statistically significant (P<0.0001) PD reduction (2.39+/- 0.92 mm and 3.44+/- 0.78 mm), CAL gain (1.50+/- 0.99 mm and 2.89 +/- 0.90 mm), increased REC (-0.89 +/- 0.58 mm and -0.56 +/- 0.92 mm) and bone fill (1.05+/- 0.94 mm and 2.13+/- 1.21 mm) when 12-month data were compared to baseline. The differences between test and control groups were statistically significant for all parameters (P<0.007) except for REC (P=0.25). CONCLUSION: The use of this bioabsorbable membrane would seem to be effective in the treatment of intrabony defects with unfavorable architecture without the use of filling materials.

Non-surgical periodontal therapy of cyclosporin A gingival overgrowth in organ transplant patients. Clinical results at 12 months.

AIM: The aim of the present study was to evaluate the clinical effects of non-surgical and supportive periodontal treatment on cyclosporin A-induced (CsA) gingival overgrowth (GO) in a group of transplant patients. METHODS: Thirty patients received etiological periodontal treatment and were placed in a -two-monthly recall program for 12 months. Plaque index, bleeding index, probing depth, degree of GO using the Seymour index (hypertrophy index, HI) and distance between the mucogingival junction and the base and the apex of each interdental papilla were recorded at baseline and repeated 12 months after treatment. RESULTS: At baseline, 22 patients had HI values >30% and were considered as ''responders''. A total of 376 gingival units (72.31%) in the anterior segments and 376 (54.97%) in the posterior ones presented GO with a mean HI value of 2.22 +/- 1.95 and 1.24 +/- 1.57, respectively. The etiological treatment resulted in a statistically significant improvement of all parameters assessed (P<0.0001). All patients had a decrease in the number of affected sites (mean HI values of 0.42 +/- 0.77 and 0.39 +/- 0.85 in the anterior and posterior segments) and none had HI values >30% and any gingival unit with score of 5 at the end of the observation period. CONCLUSIONS: Detailed instructions and intense motivation to oral home hygiene measures, inserted in an etiological treatment and a two-monthly maintenance therapy, appear to be effective in controlling the GO and in maintaining clinical improvements for prolonged time period.

Debridement and local application of tetracycline in the management of persistent periodontitis. Clinical and microbiological results after 12 months.

AIM: The purpose of this study was to evaluate the clinical and microbiological efficacy of local delivery of tetracycline in persistent periodontal lesions after topical therapy. METHODS: A total of 44 bilateral pockets 4-5 mm deep and bleeding on probing were selected in 11 non-smokers patients, 22 treated by scaling and root planing plus tetracycline fibres (test sites) and 22 with scaling and root planing alone (control sites) in a split-mouth design. Bleeding on probing, probing depth and clinical attachment level were recorded at baseline, 6 and 12 months postoperatively. The prevalence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia, Bacteroides forsythus and Treponema denticola was monitored by PCR at baseline, fibres removal, 6 and 12 months following treatment. RESULTS: The improvements in clinical parameters were greater in the tetracycline than in the control group. The reduction of bleeding on probing scores was 86.4% and 40.9%, the decrease of probing depth was 2.25 mm and 1.19 mm and the gain of clinical attachment level was 2.04 mm and 0.64 mm for test and control groups, respectively, over the 12-month period. The adjunctive use of tetracycline consistently resulted in a lower percentages of sites with detectable levels of A. actinomycetemcomitans, P. intermedia and P. gingivalis, while no differences were detected between treatments in the prevalence of T. denticola and B. forsythus. The pathogens could be eliminated from 3 periodontal pockets by debridement alone and from 12 sites by tetracycline at 12 months. CONCLUSIONS: Tetracycline local delivery gave the greatest advantage in the long-term treatment of periodontal persistent lesions.

Debridement and local application of tetracycline-loaded fibres in the management of persistent periodontitis: results after 12 months.

BACKGROUNDS/AIMS: The aim of our study was to evaluate the clinical, radiological and microbiological response to the local delivery of tetracycline (TE) of sites with persistent periodontal lesions. MATERIALS AND METHODS: The study was conducted in a split-mouth design. Nineteen patients with at least four bilateral pockets 4-5 mm and bleeding on probing (BOP) were treated with scaling and root planing (SRP) plus TE fibres (test sites) or with SRP alone (control sites). Clinical and radiological measurements were taken at baseline, 6 months and 12 months post-operatively. Subgingival plaque samples were collected at baseline, at fibres removal, 6 and 12 months following treatment and analysed by polymerase chain reaction. RESULTS: Both treatments yielded a statistically significant (p<0.05) reduction of probing depth (2.05 and 1.21 mm), gain of clinical attachment level (1.71 and 0.53 mm) and reduction of BOP scores (23.68% and 57.89%) for TE and SRP groups, respectively, when comparing 12-month data with baseline. The differences between two groups were significant. The prevalence of Treponema denticola and Bacteroides forsythus decreased after therapy in both groups but only in the test sites Actinobacillus actinomycetemcomitans and Prevotella intermedia were not yield detected. The pathogens could be eliminated from five periodontal pockets by SRP alone, while 21 TE sites were not recolonized at 12 months. CONCLUSIONS: SRP plus TE fibres gave the greatest advantage in the treatment of periodontal persistent lesions at least 12 months following treatment.