How effective is surgical therapy compared with nonsurgical debridement?

Assessment of the Effect on Periodontitis of Antibiotic Therapy and Bacterial Lysate Treatment

Periodontitis is an inflammatory process that starts with soft tissue inflammation caused by the intervention of oral bacteria. By modulating local immunity, it is possible to supplement or replace current therapeutic methods. The aim of this study was to compare the effects of an immunostimulatory treatment with the antibiotherapy usually applied to periodontitis patients. On a model of periodontitis induced in 30 rats (divided into three equal groups) with bacterial strains selected from the human oral microbiome (Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Streptococcus oralis), we administered antibiotics, bacterial lysates and saline for 10 days. Clinically, no significant lesions were observed between the groups, but hematologically, we detected a decrease in lymphocyte and neutrophil counts in both the antibiotic and lysate-treated groups. Immunologically, IL-6 remained elevated compared to the saline group, denoting the body's effort to compensate for bone loss due to bacterial action. Histopathologically, the results show more pronounced oral tissue regeneration in the antibiotic group and a reduced inflammatory reaction in the lysate group. We can conclude that the proposed bacterial lysate has similar effects to antibiotic therapy and can be considered an option in treating periodontitis, thus eliminating the unnecessary use of antibiotics.

Immunomodulation in the Treatment of Periodontitis: Progress and Perspectives

Periodontitis is one of the most common dental diseases. Compared with healthy periodontal tissues, the immune microenvironment plays the key role in periodontitis by allowing the invasion of pathogens. It is possible that modulating the immune microenvironment can supplement traditional treatments and may even promote periodontal regeneration by using stem cells, bacteria, etc. New anti-inflammatory therapies can enhance the generation of a viable local immune microenvironment and promote cell homing and tissue formation, thereby achieving higher levels of immune regulation and tissue repair. We screened recent studies to summarize the advances of the immunomodulatory treatments for periodontitis in the aspects of drug therapy, microbial therapy, stem cell therapy, gene therapy and other therapies. In addition, we included the changes of immune cells and cytokines in the immune microenvironment of periodontitis in the section of drug therapy so as to make it clearer how the treatments took effects accordingly. In the future, more research needs to be done to improve immunotherapy methods and understand the risks and long-term efficacy of these methods in periodontitis.

Early Tooth Loss after Periodontal Diagnosis: Development and Validation of a Clinical Decision Model

The aim of this study was to develop and validate a predictive early tooth loss multivariable model for periodontitis patients before periodontal treatment. A total of 544 patients seeking periodontal care at the university dental hospital were enrolled in the study. Teeth extracted after periodontal diagnosis and due to periodontal reasons were recorded. Clinical and sociodemographic variables were analyzed, considering the risk of short-term tooth loss. This study followed the transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (TRIPOD) guidelines for development and validation, with two cohorts considered as follows: 455 patients in the development phase and 99 in the validation phase. As a result, it was possible to compute a predictive model based on tooth type and clinical attachment loss. The model explained 25.3% of the total variability and correctly ranked 98.9% of the cases. The final reduced model area under the curve (AUC) was 0.809 (95% confidence interval (95% CI): 0.629–0.989) for the validation sample and 0.920 (95% CI: 0.891–0.950) for the development cohort. The established model presented adequate prediction potential of early tooth loss due to periodontitis. This model may have clinical and epidemiologic relevance towards the prediction of tooth loss burden.

Impact of Molar Furcations on Photodynamic Therapy Outcomes: A 6-Month Split-Mouth Randomized Clinical Trial

The effectiveness of adjunctive photodynamic treatment (PDT) to non-surgical periodontal therapy has been shown to depend on initial periodontal status. As molar furcation involvement impairs healing response to non-surgical periodontal therapy, the aim of this study was to evaluate the impact of furcation involvement on PDT outcomes. Thirty-six patients suffering from severe chronic periodontitis were included in a 6-month split-mouth randomized clinical trial. PDT applications used the toluidine blue O and a light-emitting diode (LED) with a red spectrum. Repeated PDT applications were performed in addition to non-surgical periodontal treatment at baseline and at 3-months. Pocket probing depth (PPD), plaque index, bleeding on probing, and clinical attachment level were recorded at baseline, and again at 3- and 6-months. Furcation sites of molars were compared to other sites of molars and non-molars. Multilevel analysis showed no PDT effect in molar furcation sites while an additional significant reduction (odds ratio = 0.67) of pockets with PPD > 5 mm in other sites at 3-months was measured. PPD reduction appeared delayed in molar furcation sites treated with PDT. There is no additional apparent benefit to use PDT in molar furcation sites for the reduction of pockets with PPD > 5 mm contrary to other sites.

Effect of Weissella cibaria on the reduction of periodontal tissue destruction in mice

BACKGROUND

Periodontitis is associated with dysbiosis of microbial flora in the oral cavity. We evaluated the effects of an oral care probiotic, Weissella cibaria CMU, on periodontal tissue destruction and regulation of inflammatory cytokines in mice with ligature-induced periodontitis (LIP).

METHODS

Fourteen-day LIP model was used. Ninety animals were randomly divided into six groups: negative control (Ctrl), positive control (LIP/Ctrl), PBS-treated (LIP/PBS), W. cibaria-low (1 × 10⁷ colony forming unit (CFU)/d; LIP/WC-L), W. cibaria-medium (1 × 10⁸ CFU/d; LIP/WC-M), and W. cibaria-high (1 × 10⁹  CFU/d; LIP/WC-H). After the 14-day treatment, alveolar bone loss was determined using micro-computed tomography. The gingival tissue and serum samples from Ctrl, LIP/Ctrl, and LIP/WC-H groups were immunoassayed for cytokines. Measurements of Porphyromonas gingivalis, total bacteria, and W. cibaria in the gingiva were performed using real-time polymerase chain reaction.

RESULTS

Mice in the LIP/WC-H group showed significant reduction in alveolar bone loss at the distal aspect of the ligatured teeth compared to those in the LIP/Ctrl group. There was a dose-dependent reduction (non-significant) in periodontal tissue destruction with increased W. cibaria concentration. Pro- and anti-inflammatory cytokines were significantly lower in LIP/WC-H than in LIP/Ctrl. The LIP/WC-H group showed significantly fewer total bacteria compared to the LIP/Ctrl group but it was similar to that in Ctrl groups, and P. gingivalis was not detected in the gingival tissue.

CONCLUSIONS

W. cibaria CMU reduces periodontal tissue destruction apparently by regulating the production of inflammatory cytokines and by reducing oral bacteria in a model for periodontal disease.

A dual-strain Lactobacilli reuteri probiotic improves the treatment of residual pockets: A randomized controlled clinical trial

Aim

To examine the adjunctive effect of a Lactobacillus reuteri probiotic (ATCC PTA 5289 & DSM 17938) on the re‐instrumentation of residual pockets.

Materials and Methods

This randomized, double‐blind, placebo‐controlled study included 39 previously non‐surgically treated periodontitis patients. A re‐instrumentation was carried out, and probiotic and/or placebo drops were applied according to the study protocoll. Patients afterwards received lozenges to use 2×/day for 12 weeks. Probing pocket depth (PPD), recession, bleeding on probing and plaque levels were analysed, next to the microbiological impact.

Results

No effects of the probiotic drops could be found. However, after 24 weeks, the overall PPD in the probiotic lozenges group (2.64 ± 0.33 mm) was significantly lower compared to the control lozenges (2.92 ± 0.42 mm). This difference was even more pronounced in moderate (4–6 mm) and deep (≥7 mm) pockets. In the probiotic lozenges group, there were also significantly more pockets converting from ≥4 mm at baseline to ≤3 mm at 24 weeks (67 ± 18% versus 54 ± 17%) and less sites in need for surgery (4 ± 4% versus 8 ± 6%). However, the probiotic products did not influence the microbiological counts of the periodontopathogens.

Conclusion

The adjunctive consumption of L. reuteri lozenges after re‐instrumentation improved the PPD reduction, without an impact on pocket colonization with periodontopathogens.

Fine-tuning multilevel modeling of risk factors associated with nonsurgical periodontal treatment outcome

This retrospective study evaluated the influence of known risk factors on nonsurgical periodontal treatment (NSPT) response using a pocket depth fine-tuning multilevel linear model (MLM). Overall, 37 patients (24 males and 13 females) with moderate-to-severe chronic periodontitis underwent NSPT. Follow-up visits at 3, 6, and 12 months included measurements of several clinical periodontal parameters. Data were sourced from a previously reported database. In a total of 1416 initially affected sites (baseline PD ≥ 4 mm) on 536 teeth, probing depth (PD) and clinical attachment loss (CAL) reductions after NSPT were evaluated against known risk factors at 3 hierarchical levels (patient, tooth, and site). For each post-treatment follow-up, the variance component models fitted to evaluate the 3-level variance of PD and CAL decrease revealed that all levels contributed significantly to the overall variance (p < 0.001). Patients who underwent NSPT and were continually monitored had curative results. All 3 hierarchical levels included risk factors influencing the degree of PD and CAL reduction. Specifically, the type of tooth, surfaces involved, and tooth mobility site-level risk factors had the strongest impact on these reductions and were highly relevant for the success of NSPT.

Macrophage immunomodulation in chronic osteolytic diseases-the case of periodontitis

Periodontitis (PD) is a chronic osteolytic disease that shares pathogenic inflammatory features with other conditions associated with nonresolving inflammation. A hallmark of PD is inflammation-mediated alveolar bone loss. Myeloid cells, in particular polymorphonuclear neutrophils (PMN) and macrophages (Mac), are essential players in PD by control of gingival biofilm pathogenicity, activation of adaptive immunity, as well as nonresolving inflammation and collateral tissue damage. Despite mounting evidence of significant innate immune implications to PD progression and healing after therapy, myeloid cell markers and targets for immune modulation have not been validated for clinical use. The remarkable plasticity of monocytes/Mac in response to local activation factors enables these cells to play central roles in inflammation and restoration of tissue homeostasis and provides opportunities for biomarker and therapeutic target discovery for management of chronic inflammatory conditions, including osteolytic diseases such as PD and arthritis. Along a wide spectrum of activation states ranging from proinflammatory to pro-resolving, Macs respond to environmental changes in a site-specific manner in virtually all tissues. This review summarizes the existing evidence on Mac immunomodulation therapies for osteolytic diseases in the broader context of conditions associated with nonresolving inflammation, and discusses osteoimmune implications of Macs in PD.

Ultrasonic Surgical Aspirator to Treat Deep Infrabony Defects: A New Flapless Minimally Invasive Approach

The primary outcome of the present study was to assess the percentage of pocket closure, and the secondary aim was to evaluate the clinical performance in terms of clinical attachment level (CAL) gain, probing pocket depth (PPD) reduction, and gingival recession (REC) after the use of cavitron ultrasonic surgical aspirator (CUSA) in deep infrabony defects. Fourteen deep infrabony defects in 11 patients who were previously treated with active periodontal therapy followed by one year of supportive periodontal therapy (at least three sessions) were additionally treated by the aid of CUSA. Eighty-six percent of the initial defects (12 out of 14) resulted in a PD < 5 mm, showing complete resolution six months after CUSA treatment, without any adverse event and with negligible pain (VAS from 0 to 3). CUSA showed potential as a method to promote pocket healing, reduce PPD, and increase clinical attachment (P < 0.001) in deep infrabony defects. This trial is registered with ClinicalTrials.gov NCT03567161.

A novel flapless approach versus minimally invasive surgery in periodontal regeneration with enamel matrix derivative proteins: a 24-month randomized controlled clinical trial

OBJECTIVES

This investigation was designed to compare the effectiveness of enamel matrix derivative (EMD) proteins in combination with flapless or flap procedure in periodontal regeneration of deep intrabony defects.

MATERIALS AND METHODS

Thirty chronic periodontitis patients who had at least one residual periodontal defect with an intrabony component of ≥3 mm were consecutively enrolled. Defects were randomly assigned to test or control treatments which both consisted of the use of EMD to reach periodontal regeneration. Test sites (n = 15) were treated according to a novel flapless approach, whereas control sites (n = 15) by means of minimally invasive surgery (MIST). Clinical and radiographic parameters were recorded at baseline, 12 and 24 months post-operatively.

RESULTS

Both therapeutic modalities yielded similar probing depth (PD) reduction and clinical attachment level (CAL) gain at 24 months. In flapless-treated sites, a mean PD reduction of 3.6 ± 1.0 mm and a CAL gain of 3.2 ± 1.1 mm were observed. In the MIST group, they were 3.7 ± 0.6 and 3.6 ± 0.9 mm. The operative chair time was twice as long in the MIST compared to the flapless group, whereas comparable patient-oriented outcomes were observed.

CONCLUSION

The flapless procedure may be successfully applied in the regenerative treatment of deep intrabony defects reaching clinical outcomes comparable with those of minimally invasive surgical approaches and may present important advantages in terms of reduction of operative chair time.

CLINICAL RELEVANCE

The use of EMD as an adjunct to non-surgical periodontal treatment may be considered a suitable option to treat defects mainly in the anterior sextants.

Decision-Making for Residual Periodontal Pockets after Aetiological Treatment

The practitioner may have difficulties making decisions regarding the most appropriate therapeutic approach in the case of the persistence of periodontal pockets after initial periodontal treatment. Several options may be considered: aetiologic retreatment, maintenance, surgery of the pocket or extraction of the tooth for strategic reasons or when the conservation of the tooth is impossible. There are no clear guidelines for the treatment decision. The aim of this article is to present the main factors involved in making a treatment decision. An algorithm and its background rationale are presented to help the practitioner make a decision about residual periodontal pockets after aetiological treatment.

Surgical and Non-Surgical Procedures Associated with Recurrence of Periodontitis in Periodontal Maintenance Therapy: 5-Year Prospective Study

BACKGROUND AND OBJECTIVE

Prospective studies that investigated the influence of surgical and nonsurgical procedures in the recurrence of periodontitis and tooth loss in periodontal maintenance therapy (PMT) programs have not been previously reported. The objective of this study was to evaluate longitudinally the recurrence of periodontitis in regular compliers (RC) and irregular compliers (IC) individuals undergoing surgical and non-surgical procedures over 5 years in a program of PMT.

MATERIALS AND METHODS

A total of 212 individuals participated in this study. Full-mouth periodontal examination including bleeding on probing, probing depth, and clinical attachment level were determined at all PMT visits over 5 years. The recurrence of periodontitis was evaluated in RC and IC individuals undergoing surgical and non-surgical procedures in PMT. The influences of risk variables of interest were tested through univariate analysis and multivariate logistic regression.

RESULTS

Recurrence of periodontitis was significantly lower among RC when compared to IC. Individuals with recurrence of periodontitis and undergoing surgical procedures showed higher probing depth and clinical attachment loss than those who received non-surgical procedures. Recurrence of periodontitis was higher in individual undergoing surgical procedures and irregular compliance during PMT.

CONCLUSIONS

Irregular compliance and surgical procedures in individuals undergoing PMT presented higher rates of recurrence of periodontitis when compared to regular compliant patients undergoing non-surgical procedures.

Crevicular fluid levels of interleukin-8, interleukin-17 and soluble intercellular adhesion molecule-1 after regenerative periodontal therapy

Objective:

The aim of this study is to evaluate the influence of regenerative periodontal therapy on clinical parameters and interleukin-8 (IL-8), IL-17 and soluble intercellular adhesion molecule-1 (sICAM-1) levels in gingival crevicular fluid (GCF) of subjects with chronic periodontitis (CP).

Materials and Methods:

Fifteen patients received demineralized freeze-dried bone allograft (DFDBA) surgically to the site of infrabony defect. Clinical periodontal indices were recorded, and GCF samples were collected at baseline and at the 6^th and the 9^th month after the surgery.

Results:

Except plaque index, all clinical parameters improved following surgery (P < 0.05). The volume of GCF diminished from baseline to follow-up periods (P < 0.05). However, no effect was observed on the total amount of IL-8, IL-17 and sICAM-1 in GCF.

Conclusion:

DFDBA improved clinical outcome in CP subjects and was effective on decreasing the volume of GCF, but no effect was determined on IL-8, IL-17 and sICAM-1. Findings did not indicate a direct relationship between biochemical parameters and periodontal healing after demineralized freeze-dried bone grafting.

Leptin effects on the regenerative capacity of human periodontal cells

Obesity is increasing throughout the globe and characterized by excess adipose tissue, which represents a complex endocrine organ. Adipose tissue secrets bioactive molecules called adipokines, which act at endocrine, paracrine, and autocrine levels. Obesity has recently been shown to be associated with periodontitis, a disease characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium, and also with compromised periodontal healing. Although the underlying mechanisms for these associations are not clear yet, increased levels of proinflammatory adipokines, such as leptin, as found in obese individuals, might be a critical pathomechanistic link. The objective of this study was to examine the impact of leptin on the regenerative capacity of human periodontal ligament (PDL) cells and also to study the local leptin production by these cells. Leptin caused a significant downregulation of growth (TGFβ1, and VEGFA) and transcription (RUNX2) factors as well as matrix molecules (collagen, and periostin) and inhibited SMAD signaling under regenerative conditions. Moreover, the local expression of leptin and its full-length receptor was significantly downregulated by inflammatory, microbial, and biomechanical signals. This study demonstrates that the hormone leptin negatively interferes with the regenerative capacity of PDL cells, suggesting leptin as a pathomechanistic link between obesity and compromised periodontal healing.

Beneficial effects of adiponectin on periodontal ligament cells under normal and regenerative conditions

Type 2 diabetes and obesity are increasing worldwide and linked to periodontitis, a chronic disease which is characterized by the irreversible destruction of the tooth-supporting tissues, that is, periodontium. The mechanisms underlying the association of diabetes mellitus and obesity with periodontal destruction and compromised periodontal healing are not well understood, but decreased plasma levels of adiponectin, as found in diabetic and obese individuals, might be a critical mechanistic link. The aim of this in vitro study was to examine the effects of adiponectin on periodontal ligament (PDL) cells under normal and regenerative conditions, and to study the regulation of adiponectin and its receptors in these cells. Adiponectin stimulated significantly the expression of growth factors and extracellular matrix, proliferation, and in vitro wound healing, reduced significantly the constitutive tumor necrosis factor-α expression, and caused a significant upregulation of its own expression. The beneficial actions of enamel matrix derivative on a number of PDL cell functions critical for periodontal regeneration were partially enhanced by adiponectin. The periodontopathogen Porphyromonas gingivalis inhibited the adiponectin expression and stimulated the expression of its receptors. In conclusion, reduced levels of adiponectin, as found in type 2 diabetes and obesity, may compromise periodontal health and healing.

Lessons learned and unlearned in periodontal microbiology

Periodontal diseases are initiated by bacterial species living in polymicrobial biofilms at or below the gingival margin and progress largely as a result of the inflammation elicited by specific subgingival species. In the past few decades, efforts to understand the periodontal microbiota have led to an exponential increase in information about biofilms associated with periodontal health and disease. In fact, the oral microbiota is one of the best-characterized microbiomes that colonize the human body. Despite this increased knowledge, one has to ask if our fundamental concepts of the etiology and pathogenesis of periodontal diseases have really changed. In this article we will review how our comprehension of the structure and function of the subgingival microbiota has evolved over the years in search of lessons learned and unlearned in periodontal microbiology. More specifically, this review focuses on: (i) how the data obtained through molecular techniques have impacted our knowledge of the etiology of periodontal infections; (ii) the potential role of viruses in the etiopathogenesis of periodontal diseases; (iii) how concepts of microbial ecology have expanded our understanding of host-microbe interactions that might lead to periodontal diseases; (iv) the role of inflammation in the pathogenesis of periodontal diseases; and (v) the impact of these evolving concepts on therapeutic and preventive strategies to periodontal infections. We will conclude by reviewing how novel systems-biology approaches promise to unravel new details of the pathogenesis of periodontal diseases and hopefully lead to a better understanding of their mechanisms.

Regulation of regenerative periodontal healing by NAMPT

Periodontitis is an inflammatory disease characterized by destruction of the tooth-supporting tissues. Obese individuals have an increased risk of periodontitis, and elevated circulating levels of nicotinamide phosphoribosyltransferase (NAMPT) may be a pathomechanistic link between both diseases. Recently, increased levels of NAMPT have also been found in patients with periodontitis, irrespective of the presence of obesity. This in vitro study sought to examine the effects of NAMPT on the regenerative capacity of human periodontal ligament (PDL) cells and, thereby, periodontal healing. PDL cells treated with enamel matrix derivative (EMD), which was used to mimic regenerative healing conditions in vitro, were grown in the presence and absence of NAMPT for up to 14 d. EMD stimulated significantly (P < 0.05) the expression of growth factors and their receptors, matrix molecules, osteogenesis-associated factors, and wound closure and calcium accumulation. In the presence of NAMPT, all these stimulatory effects were significantly (P < 0.05) reduced. In conclusion, the beneficial effects of EMD on a number of PDL cell functions critical for periodontal regeneration are counteracted by NAMPT. Enhanced levels of NAMPT, as found in obesity and periodontal inflammation, may compromise the regenerative capacity of PDL cells and, thereby, periodontal healing in the presence of EMD.

Minimally-invasive non-surgical periodontal therapy

Periodontitis is a complex disease that has both oral and systemic consequences. The treatment of periodontitis may be both surgical and non-surgical but, in recent years, there has been a shift towards managing disease non-surgically in preference to surgery. Fundamental to all types of therapy is the patient's role in disease control, in the form of self-performed plaque control, and it is important that the patient understands this. Non-surgical periodontal therapy has a long history and has traditionally been carried out using a variety of hand and powered instruments, the objective being root surface disinfection by the removal of plaque, calculus and contaminated root cementum. However, over the last 30 years or so, it has become apparent that calculus does not cause disease, cementum does not become significantly infected and bacteria and their toxins are only loosely adherent to the diseased root surface. This has led to the development of less invasive instrumentation principles which may be better for patients, more cost-effective and more easily applied in different clinical settings.

CLINICAL RELEVANCE

This paper aims to describe and justify a minimally-invasive approach to the management of the diseased root surface in periodontitis, to clarify the terminology used and to suggest how these principles may be applied in general practice.

Clinical and microbiological changes after minimally invasive therapeutic approaches in intrabony defects: a 12-month follow-up

OBJECTIVES

This 12-month randomized, controlled trial evaluated the clinical effects and microbiological changes of minimally invasive nonsurgical and surgical approaches for the therapy of intrabony defects.

MATERIALS AND METHODS

Twenty-nine subjects with intrabony defects in single-rooted tooth were randomly assigned to; (1) minimally invasive nonsurgical technique (MINST) or (2) minimally invasive surgical technique (MIST). Quantities of Aggregatibacter actinomycetemcomitans, Tannerella forsythia, and Porphyromonas gingivalis, determined by using real-time PCR, were evaluated at baseline, 3, 6, and 12 months after the treatments. Clinical recordings--probing depth (PD), position of the gingival margin (PGM), and relative clinical attachment level (RCAL)--were obtained at baseline and 12 months post-therapy. The primary outcome variable of the study was RCAL.

RESULTS

Both treatment modalities resulted in an improvement in all clinical recordings, with significant PD reductions (p < 0.05), RCAL gains (p < 0.05), and no change in the PGM (p > 0.05) after 12 months in both MINST and MIST groups. No clinical differences were observed between groups (p > 0.05). Regarding the microbiological outcomes, at the re-examinations, a significant decrease was observed for T. forsythia and P. gingivalis when compared with baseline (p < 0.05) for both treatments. The amount of A. actinomycetemcomitans did not reduced decrease throughout the study (p > 0.05). Intergroup differences in the microbiological assay were not found at any time point (p > 0.05).

CONCLUSIONS

Both MINST and MIST provided comparable clinical results and microbiological changes in the treatment of intrabony defects over 12 months follow-up.

CLINICAL RELEVANCE

This randomized, controlled, parallel trial revealed that both therapeutic modalities may promote clinical and microbiological benefits at 12 months post-therapy.

Morphometric study of the root anatomy in furcation area of mandibular first molars

Furcation involvement in periodontal disease has been a challenge for the dentist.

Interactions of enamel matrix derivative and biomechanical loading in periodontal regenerative healing

BACKGROUND

Although enamel matrix derivative (EMD) has been shown to promote periodontal regeneration, it is unknown whether the actions of EMD are modulated by occlusal loading. This in vitro study was performed to investigate whether biomechanical forces regulate the response of periodontal ligament (PDL) cells to EMD.

METHODS

Human PDL cells were treated with EMD in the presence and absence of cyclic tensile strain (CTS) of various magnitudes for ≤ 14 days. Synthesis of transforming growth factor (TGF)-β1, vascular endothelial growth factor (VEGF), growth factor receptors, collagen, and runt-related transcription factor 2- (RUNX2), cell numbers and adhesion, wound fill rate, and calcium accumulation were analyzed by real-time polymerase chain reaction, enzyme-linked immunosorbent assay, a wound healing assay, and alizarine red S staining.

RESULTS

Wound fill rate, cell numbers and adhesion, and expression of TGF-β1, VEGF, collagen, and RUNX2 were significantly increased by EMD. In the presence of CTS, the EMD-induced effects were significantly reduced. The inhibition of the EMD-upregulated VEGF expression by CTS was blocked by a specific inhibitor of nuclear factor-kappa B signaling. Moreover, CTS downregulated receptors for growth factors involved in the actions of EMD. CTS also antagonized significantly the EMD-induced calcium deposition.

CONCLUSIONS

These in vitro findings suggest that the beneficial actions of EMD on PDL cell functions critical for periodontal regeneration are jeopardized by biomechanical loading. Clinical studies should clarify whether protection of teeth against occlusal forces in the early healing stage may positively affect the outcome of regenerative therapy with EMD.

Microscope-controlled glass bead blasting: a new technique

OBJECTIVE

The aim of periodontal therapy is the healing of periodontal inflammation; the protection of the attachment and the alveolar bone; and the regeneration of the periodontal structures. In the therapy of periodontitis, supra- and subgingival scaling and root planing plays a main role. The procedure described combines perfect root cleaning without scaling and root planing and minimal invasive periodontal surgery without a scalpel.

MATERIAL AND METHODS

Glass beads of 90 μm were used with the kinetic preparation unit PrepStart(®) under a pressure of 0.5-5 bar. This technique was practised only under visual control using the OPMI(®) PRO Magis microscope. Seven examinations were carried out at baseline after 3, 6, 12, 18, 24, and 36 months.

RESULTS

Time shows a statistically significant influence on all of the considered target variables (P < 0.0001 for all). As the according estimate is negative, probing depth decreases over time. The major decrease seems to be during the first 6 months. Considering probing depth, plaque on the main effect root shows significant influence (again, P < 0.0001 for all). Observations with high probing depth at the beginning were faster than those with low probing depth. The same characteristic appears by attachment level. Patients with more loss of attachment show more gain.

CONCLUSIONS

Using microscope-controlled glass bead blasting results in a perfectly clean root surface using visual control (magnification 20×). Microscope-controlled glass bead blasting is therefore a good alternative to periodontal surgery.

Anti-inflammatory effects of EMD in the presence of biomechanical loading and interleukin-1β in vitro

Enamel matrix derivative (EMD) used to promote periodontal regeneration has been shown to exert anti-inflammatory effects. This in vitro study was performed to investigate if the anti-inflammatory actions of EMD are modulated by the local cellular environment, such as inflammation or occlusal, i.e., biomechanical, loading. Human periodontal ligament cells were seeded on BioFlex plates and incubated with EMD under normal, inflammatory, and biomechanical loading conditions for 1 and 6 days. In order to mimic inflammatory and biomechanical loading conditions in vitro, cells were stimulated with interleukin (IL)-1β and exposed to dynamic tensile strain, respectively. The gene expression of IL-1β, IL-1 receptor antagonist (IL-1RN), IL-6, IL-8, IL-10, and cyclooxygenase (COX)-2 was analyzed by real-time RT-PCR and the IL-6 protein synthesis by enzyme-linked immunoassay. For statistical analysis, Student's t test, ANOVA, and post-hoc comparison tests were applied (p < 0.05). EMD downregulated significantly the expression of IL-1β and COX-2 at 1 day and of IL-6, IL-8, and COX-2 at 6 days in normal condition. In an inflammatory environment, the anti-inflammatory actions of EMD were significantly enhanced at 6 days. In the presence of low biomechanical loading, EMD caused a downregulation of IL-1β and IL-8, whereas high biomechanical loading significantly abrogated the anti-inflammatory effects of EMD at both days. Neither IL-1RN nor IL-10 was upregulated by EMD. These data suggest that high occlusal forces may abrogate anti-inflammatory effects of EMD and should, therefore, be avoided immediately after the application of EMD to achieve best healing results.

The biology, prevention, diagnosis and treatment of periodontal diseases: scientific advances in the United States

BACKGROUND

Major scientific advances in periodontology in the past 150 years have fundamentally changed how clinicians detect and treat periodontal diseases. These advances include the demonstration that gingivitis and periodontitis are biofilm-induced infections caused by components of the indigenous oral microbiota, and that host inflammatory-immunologic responses to these microbial challenges are responsible for most of the observed tissue damage.

TYPES OF STUDIES REVIEWED

In this brief overview, the authors focus on the discovery of the relationships between dental plaque and the host periodontal tissues. They highlight some of the pioneers in the United States who shaped new approaches to prevention and treatment of periodontal disease.

RESULTS

Biofilms that cause gingivitis and periodontitis are complex polymicrobial communities that are resistant to antimicrobial agents and host defense mechanisms. An increased understanding of natural inflammation-resolving mechanisms suggests that control of inflammation is at least as important as is antimicrobial therapy in the treatment of periodontal infections. Data from randomized controlled clinical trials have shown that most conventional forms of periodontal therapy are effective as long as patients comply with posttreatment maintenance programs.

CONCLUSIONS

Many mechanisms involved in the repair and regeneration of periodontal tissues have been identified. Results of laboratory studies of factors that enhance prevention and treatment of periodontal disease have made the transition to clinical practice. Advances in the fields of molecular biology, human genetics and stem cell biology have set the stage for significant discoveries that will pave the way for the development of procedures needed for the predictable regeneration of periodontal tissues. As a result, new generations of people in the United States can expect to retain a healthy and functional dentition for a lifetime.

Repeated scaling versus surgery in young adults with generalized advanced periodontitis

BACKGROUND

Residual probing depth (PD) after subgingival scaling can be treated with repeated scaling or periodontal surgery. Ambiguous results about the additional clinical benefit of a second scaling procedure exist. Therefore, we performed a prospective study comparing the clinical results of repeated subgingival scaling versus periodontal surgery in 30- to 40-year-old subjects with generalized advanced periodontitis.

METHODS

Twenty-six subjects (mean age, 37 +/- 3 years) were treated after an initial examination (t(1)), initial subgingival scaling, and baseline examination (t(2)) with a randomly assigned second subgingival scaling (test) and periodontal surgery (control) in a split-mouth design. The final examination (t(3)) took place 6 months postoperatively. Intraindividual comparisons of mean PD and clinical attachment level (CAL) were analyzed.

RESULTS

PD was reduced from 4.1 +/- 0.2 mm initially (t(1)) to 3.1 +/- 0.1 mm at baseline (t(2)), and to 2.9 +/- 0.1 mm at the end of the study (t(3)) for the test sites; and from 4.5 +/- 0.2 mm (t(1)) to 3.5 +/- 0.1 mm (t(2)), and 3.1 +/- 0.1 mm (t(3)) for the control sites. The total PD decrease from t(1) to t(3) was significant (P <0.001) for both therapies. PD reduction from t(2) to t(3) was only significant (P <0.001) for control sites, resulting in a significant (P = 0.010) difference between test and control at the final examination. CAL increased 0.2 +/- 0.1 mm (t(2)) plus 0.3 +/- 0.1 mm (t(3)) for the test sites and 0.2 +/- 0.1 mm (t(2)) plus 0.2 +/- 0.1 mm (t(3)) for the control sites. Total CAL gain was statistically significant for the test and control sites. CAL gain from t(2) to t(3) was only significant (P = 0.022) for the test sites.

CONCLUSIONS

Both treatments reduced PD and increased CAL. A second subgingival scaling resulted in significant additional CAL gain and reduced the need for surgery.