Maintenance therapy for teeth and implants

The Effects of Dental Hygiene Instruments on Streptococcus sanguinis Adhesion to Titanium Implant Abutments

INTRODUCTION

Maintenance of dental implant with different hygiene methods or instruments may cause a surface alteration. It directly affects bacterial colonization and adhesion on titanium implant surfaces that result in peri-implant diseases. This study aimed to compare the Streptococcus sanguinis (S. sanguinis) adhesion on titanium implant abutments after instrumentation with a rubber cup with pumice and erbium, chromium-doped: yttrium, scandium, gallium, and garnet (Er, Cr: YSGG) laser using scanning electron microscope (SEM) observation and colony-forming unit (CFU) measurement.

METHODS

Twenty-one MegaGen titanium implant abutments were randomly distributed into three groups. Seven abutments were respectively selected for the control/untreated (C) group, while the other two groups were treated with rubber cups with pumice (P) and Er, Cr: YSGG laser (L). All samples were cultured with S. sanguinis for bacterial colonization and adhesion. One sample for each group was selected for SEM observation, while the other samples were prepared for CFU calculation.

RESULTS

For SEM results, at 2,000× magnification, machining marks were intact in the C group, roughened in the L group, and smoothened in the P group. At 5,000× and 10,000× magnifications, moderate colonies of S. sanguinis were revealed in C and L groups, while sparse bacterial colonies were detected in the P group. However, for CFU results, statistical analysis showed no significant value (p>0.05) comparing all three groups.

CONCLUSION

P instrumentation revealed a lesser amount of S. sanguinis adhesion in SEM photographs, but no statistical significance of CFU results was noted for all three groups.

Maintenance of peri-implant health in general dental practice

The long-term maintenance or restoration of peri-implant tissues' health depends on the strategic implementation of preventive measures and interventions. These measures should be initiated before implant placement and continued throughout a patient's lifetime, as part of a tailored and comprehensive supportive peri-implant care (SPIC) programme. Central to the clinical efforts of maintaining and rehabilitating peri-implant tissues are several key factors, including the ongoing assessment and frequent monitoring of tissue health and stability, proactive oral health promotion, the control of risk factors and indicators and the provision of professional plaque biofilm removal. It is of paramount importance to underline that SPIC should not limit its scope exclusively to patients already in a state of peri-implant health; in fact, it is imperative that it should extend its protective effect to individuals who have been previously diagnosed and treated for peri-implant diseases, focusing on preventing its recurrence and progression, thereby avoiding further complications, such as implant loss.This narrative review presents an overview of the current literature on the maintenance of peri-implant tissues' health and the steps of SPIC providing insights into the critical factors to be considered when managing dental implant patients in the general dental practice.

Quantity and Size of Titanium Particles Released from Different Mechanical Decontamination Procedures on Titanium Discs: An In Vitro Study

Complications such as peri-implantitis could ultimately affect the survival of a dental implant. The prevention and treatment of peri-implant diseases require managing bacterial biofilm and controlling environmental risks, including the presence of pro-inflammatory titanium (Ti) particles in the peri-implant niche. Objectives included the evaluation of the size and quantity of Ti particles released from moderately roughened Ti surfaces during common mechanical surface decontamination methods. One hundred and forty moderately roughened Ti discs were divided into seven groups (n = 20 per group); six groups received mechanical decontamination procedures (ultrasonic scaling (US) with a metal tip and poly-ether-ketone (PEEK) under low and medium power settings, air-polishing with erythritol powder, and Ti brush), and the control group underwent air-water spray using a dental triplex. The rinsing solution was collected for Ti mass analysis using inductively coupled plasma mass spectrometry (ICPMS), as well as for Ti particle size and count analysis under scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS). US metal tip instrumentation generated 34.00 ± 12.54 μg and 34.44 ± 6.08 μg of Ti under low and medium power settings, respectively. This amount of Ti generation was significantly higher than other instrumentation methods. The mean Ti particle size of the US groups ranged from 0.89 ± 0.27 μm to 1.25 ± 0.24 μm. No statistically significant difference was found in the particle size among US groups and Ti brush group (1.05 ± 0.11 μm), except for US with the PEEK tip, where a significantly smaller mean particle diameter was found at the low power setting (0.89 ± 0.27 μm). Mechanical instrumentation can produce Ti particulates and modify the implant surfaces. US using a metal tip generated the highest amount of Ti with smaller Ti size particles compared to all other commonly used mechanical surface instrumentations. The EDS analysis confirmed Ti in PEEK US tips. It can be suggested that deterioration from the PEEK US tip and Ti brush, as observed under SEM, is an additional source of Ti release during Ti surface decontamination.

Statins and oral biofilm: Simvastatin as a promising drug to control periodontal dysbiosis

OBJECTIVES

This study evaluated antimicrobial activity of atorvastatin, pravastatin, rosuvastatin, and simvastatin against oral bacteria, and the interaction of simvastatin with standard antimicrobials (amoxicillin and metronidazole).

METHODS

Minimal inhibitory concentration assays were performed with Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum, Actinomyces odontolyticus, Streptococcus oralis, Streptococcus mitis, Streptococcus salivarius, Streptococcus sanguinis, and Streptococcus gordonii; checkerboard microdilution assays between simvastatin and standard antimicrobials; monospecies and multispecies biofilms.

RESULTS

Simvastatin showed the best antimicrobial activity against most species (MIC range from 3.12 to 25 μg/ml), highlighting the sensitivity of P. gingivalis. In the checkerboard assay, synergistic interaction was found between simvastatin and amoxicillin against S. oralis and S. sanguinis. P. gingivalis biofilm was inhibited by simvastatin at 10 and 50× Minimal inhibitory concentration, with similar effects to metronidazole. For multispecies biofilm, SMV reduced the biofilm metabolic activity (79%) and total counts (87%), comparable to amoxicillin. Simvastatin also reduced bacterial counts of Veilonnella parvula, P. gingivalis, Streptococcus mutans, Actinomyces naeslundii, P. intermedia, and Capnocytophaga ochracea in the multispecies biofilm.

CONCLUSIONS

Simvastatin showed antimicrobial and antibiofilm activity against oral bacteria and may contribute to the control of dysbiosis, and may be considered in clinical studies as an adjuvant in the treatment of periodontitis.

Etiology, pathogenesis and treatment of peri-implantitis: A European perspective

Peri-implantitis is a plaque-associated pathological condition occurring in tissues around dental implants. It is characterized by inflammation in the peri-implant mucosa and progressive loss of supporting bone. Over the last 30 years, peri-implantitis has become a major disease burden in dentistry. An understanding of the diagnosis, etiology and pathogenesis, epidemiology, and treatment of peri-implantitis must be a central component in undergraduate and postgraduate training programs in dentistry. In view of the strong role of European research in periodontology and implant dentistry, the focus of this review was to address peri-implantitis from a European perspective. One component of the work was to summarize new and reliable data on patients with dental implants to underpin the relevance of peri-implantitis from a population perspective. The nature of the peri-implantitis lesion was evaluated through results presented in preclinical models and evaluations of human biopsy material together with an appraisal of the microbiological characteristics. An overview of strategies and outcomes presented in clinical studies on nonsurgical and surgical treatment of peri-implantitis is discussed with a particular focus on end points of therapy and recommendations presented in the S3 level Clinical Practice Guideline for the prevention and treatment of peri-implant diseases.

Enamel Matrix Derivative Suppresses Chemokine Expression in Oral Epithelial Cells

Epithelial cells in periodontitis patients increasingly express chemokines, suggesting their active involvement in the inflammatory process. Enamel matrix derivative (EMD) is an extract of porcine fetal tooth germs clinically applied to support the regrowth of periodontal tissues. Periodontal regeneration might benefit from the potential anti-inflammatory activity of EMD for epithelial cells. Our aim was, therefore, to set up a bioassay where chemokine expression is initiated in the HSC2 oral squamous carcinoma cell line and then test EMD for its capacity to lower the inflammatory response. To establish the bioassay, HSC2 cells being exposed to TNFα and LPS from E. coli (Escherichia coli) or P. gingivalis (Porphyromonas gingivalis) were subjected to RNAseq. Here, TNFα but not LPS caused a robust increase of chemokines, including CXCL1, CXCL2, CXCL8, CCL5, and CCL20 in HSC2 cells. Polymerase chain reaction confirmed the increased expression of the respective chemokines in cells exposed to TNFα and IL-1β. Under these conditions, EMD reduced the expression of all chemokines at the transcriptional level and CXCL8 by immunoassay. The TGF-β receptor type I kinase-inhibitor SB431542 reversed the anti-inflammatory activity. Moreover, EMD-activated TGF-β-canonical signaling was visualized by phosphorylation of smad3 and nuclear translocation of smad2/3 in HSC2 cells and blocked by SB431542. This observation was confirmed with primary oral epithelial cells where EMD significantly lowered the SB431542-dependent expression of CXCL8. In summary, our findings suggest that TGF-β signaling mediates the effects of EMD to lower the forced expression of chemokines in oral epithelial cells.

Advanced and Readily-Available Wireless-Powered Blue-Light-Implant for Non-Invasive Peri-Implant Disinfection

Non-invasive light-based antibacterial therapy has a good prospect in non-surgical treatment of peri-implant infections. However, its applications are severely limited by poor penetration of light into human tissues, leading to unsatisfying outcomes. Moreover, as an essential prerequisite for traditional light therapy, lasers can no longer meet the patients' needs for convenient treatment at any time. To break through the spatial and temporal limitations of traditional light therapy, a wireless-powered blue-light zirconia implant for readily available treatment of peri-implant infection is proposed. In space, complete irradiation to complex peri-implant structure is realized by the built-in wireless-powered light source, thus improving the efficacy. In time, wireless-powering allows timely and controllable anti-infection treatment. Blue micro-light emitting diodes are used as therapeutic light sources, which effectively kill peri-implant infection-related bacteria without exogenous photosensitive agents. Porphyromonas gingivalis biofilm on implant surface can be completely killed after 20 min irradiation in vitro. The bactericidal rate of peri-implant methicillin-resistant Staphylococcus aureus infection reaches 99.96 ± 0.03% under 30 min per day blue light exposure in vivo. Within the scope of this study, the treatment of peri-implant infection with blue-light implant has preliminary feasibility, giving a new approach to non-invasive treatment of deep oral infections, including peri-implant infections.

Is Laser Therapy an Adjuvant in the Treatment of Peri-Implant Mucositis? A Randomized Clinical Trial

(1) Background: Early diagnosis and treatment of peri-implant mucositis may reduce inflammatory markers and halt the progression of the condition to peri-implantitis. Adjunctive laser treatment may have therapeutic benefits that are not yet well known. The aim of this study was to determine the advantages and limitations of laser therapy as an adjuvant in the treatment of peri-implant mucositis. (2) Methods: A total of 42 patients with at least 2 implants situated in different hemiarches were included in this study and divided into two groups: G1 (received laser therapy) and G2 (no laser therapy). Periodontal health status indices were recorded at the initial moment (T0), and all patients underwent non-surgical debridement therapy accompanied by oral hygiene training. In patients from group G1, one implant site received adjuvant laser therapy (subgroup IL), and the other one did not receive active laser light (IC). The plaque index (PI), probing pocket depth (PPD), and bleeding on probing (BOP) values recorded after 3 months (T1) and 6 months (T2) were analyzed and compared with those at T0. (3) Results: PI values considerably reduced at moment T1 and T2 for both G1 and G2 (p = 0.0031). PPD was also reduced, but the difference between the groups and the three recording moments was not statistically significant. Statistically significant differences were found when comparing the BOP values between G1 IL and G1 IC for T0/T1 (p = 0.0182) and T1/T2 (p < 0.0001), but there was no significant difference between G2 and G1 IL or G1 IC. (4) Conclusions: Laser therapy as an adjunct to conventional treatment of peri-implant mucositis leads to a statistically significant reduction in bleeding on probing at 3-month and 6-month re-evaluations. Moreover, it leads to an evident reduction in probing depth but with no statistical significance. These results should be interpreted with caution, and more in-depth research should be performed to create a complete laser therapy protocol for peri-implant mucositis.

6 mm short versus 11 mm long inter-foraminal implants in the full-arch rehabilitation of edentulous non-atrophic mandibles: 5-year results from a multicenter randomized controlled trial

OBJECTIVE

The aim of this multicenter parallel-group randomized controlled trial is to compare, in the same clinical scenario, 6 mm short with 11 mm long implants for the rehabilitation of completely edentulous non-atrophic mandibles.

MATERIALS AND METHODS

Thirty patients in three study centers received a fixed full-arch mandibular rehabilitation supported by five inter-foraminal implants, with no need for bone augmentation procedures. Patients were randomly allocated (1:1 ratio), at the time of surgery, to test (6 mm implants) or control group (11 mm implants). After 3 months, a screw-retained full-arch prosthesis was positioned (baseline). Peri-implant marginal bone level change (MBLc, primary outcome) together with implant and prosthesis survival rate, and biological/technical complications (secondary outcomes) were evaluated up to 5 years.

RESULTS

Twenty seven patients were controlled at 5 years (3 drop-outs). No implant or prosthesis loss occurred. No significant intergroup difference for biological/technical complications (p > .05, Fisher's exact test) and no significant intragroup and intergroup difference in the MBLc values were registered (test -0.03 ± 0.17 mm and control -0.13 ± 0.32 mm at 5-years; p > .025, one-sided Mann-Whitney U-test).

CONCLUSIONS

When used in comparable anatomic, surgical, and prosthetic conditions, no difference in the clinical and radiographic outcomes between 6-mm and 11-mm implants was observed at 5 years of follow-up. Short implants showed to be a reliable option for the rehabilitation of completely edentulous non-atrophic mandibles. There is growing clinical evidence supporting the use of short implants, even in the case of non-atrophic sites.

Periodontal maintenance: individual patient responses and discontinuations

Aim

There is a lack of data on long-term impact of different psychological variables on periodontitis. Aim of the current study was to investigate the impact of psychological factors in patients with chronic periodontitis (CP; according to the 1999 Classification of Periodontal Diseases) to explain adherence to or discontinuation of supportive periodontal therapy (SPT) in a university setting.

Methods

A sample of n = 119 patients were examined in a questionnaire-based, cross-sectional survey. All patients had received active periodontal treatment (APT) and were reevaluated in a university setting (Kiel) before 2016 [T1: start SPT]. Patients who showed sufficient adherence to SPT of ≥ 2 years (maximum ± 6 months of deviation between SPT intervals, last visit and questionnaire at T2) were assigned to the adherence group (AG: n = 58), or, if they interrupted SPT or stopped treatment altogether, to the non-adherence group (NAG: n = 61). In addition to dental parameters, we assessed socio-demographic, treatment-related (critical attitudes/complaints), dental as well as psychological variables (especially psychological attachment, but also dental fear, patient participation style, personality functioning) and examined between-group differences as well as possible mediating factors of non-adherence to treatment continuation.

Results

For both groups we found similar average observation time (NAG/AG: 15.9(8.9)/14.9(10.6)years). There were significant differences in age, critical attitudes, dental fear, and patient participation style between the groups. With the help of exploratory sequential mediation models, we found a significant indirect pathway of the impact of attachment anxiety on discontinuation of treatment mediated through dental fear and number of critical attitudes/complaints.

Conclusion

Considering the limitations, dentists should be aware of personality-related risk-factors such as attachment anxiety as well as their interplay with levels of dental fear and critical attitudes which may influence adherence to SPT.

Trial registration: The clinical trial was retrospectively registered in the DRKS—German Clinical Trials Register (https://www.drks.de) with registration DRKS00030092 (26/08/2022).

Effect of Three Chlorhexidine-Based Mouthwashes on Human Gingival Fibroblasts: An In Vitro Study

Mouthwashes containing chlorhexidine (CHX) are deemed to be associated with dose-dependent side effects, including burning sensation and taste alteration. To overcome these drawbacks, mouthwashes with CHX at lower concentrations with or without adjunctive agents are proposed. The aim of this in vitro study was to investigate the effects of three CHX-based mouthwashes on human gingival fibroblasts (HGFs). After 3 days of cell culture, groups were randomly treated for 30 s, 60 s or 120 s with (a) CHX 0.05% in combination with cetylpyridnium chloride (CPC) 0.05%; (b) CHX 0.1%; (c) CHX 0.2%; or (d) NaCl as control. Cell viability, cytotoxicity and apoptosis were evaluated at 2 h, 3 days and 6 days after the exposure to the different solutions. Similar cell viability values were found among the test groups at all time points. At day 0, higher cytotoxicity was measured in the group treated with CHX 0.02%, in particular after long application time (120 s), while no significant difference was found between CHX + CPC and the control group. All the investigated mouthwashes were well tolerated by HGF cells for the tested application times. The highest cytotoxic effect was observed for CHX 0.2%; therefore, clinicians should consider limiting its usage to carefully selected clinical situations.

Influence of Periodontitis, Implant, and Prosthesis Characteristics on the Peri-Implant Status: A Cross-Sectional Study

Background

The association between peri-implant diseases and the periodontal, implant, and prosthesis characteristics has been characterized in various ways.

Purpose

The aim of this study was to evaluate the link between the peri-implant and periodontal status and the influence of implant and prosthesis parameters during implant follow-up.

Materials and Methods

One hundred and seven patients with a total of 310 implants that had at least one year of function who were attending periodontal and implant maintenance at a university clinic setting were included in this cross-sectional study. The demographic, periodontal, peri-implant tissue, implant, and prosthesis parameters were recorded. A pocket depth > 4 mm with bleeding on probing defined periodontal/peri-implant soft tissue diseased sites. Analyses were performed at the patient and implant levels using univariable and multivariable mixed regression analysis.

Results

The mean implant follow-up was 7.22 years. At the patient level, the bleeding on probing and pocket depth measurements were more pronounced around the implant than around the teeth. The opposite was observed for plaque and the clinical attachment levels. At the implant level, multivariable analysis showed that the periodontal and corresponding peri-implant tissue parameters, such as diseased sites, were closely related. The implant location, bone level, and number were selectively associated with the implant bone level, while cemented retention and emergence restoration profile influenced the implant pocket depth.

Conclusions

The present study suggested that clinical peri-implant and periodontal soft tissue statuses were different, which could be a consequence of the initial implant and prosthesis healing process. However, during implant follow-up, the peri-implant parameters were predominantly associated with their corresponding periodontal parameters regardless of an association with the implant and prosthesis characteristics. This trial is registered with ClinicalTrials.gov ID: NCT03841656.

Classic vs. Novel Antibacterial Approaches for Eradicating Dental Biofilm as Adjunct to Periodontal Debridement: An Evidence-Based Overview

Periodontitis is a multifactorial chronic inflammatory disease that affects tooth-supporting soft/hard tissues of the dentition. The dental plaque biofilm is considered as a primary etiological factor in susceptible patients; however, other factors contribute to progression, such as diabetes and smoking. Current management utilizes mechanical biofilm removal as the gold standard of treatment. Antibacterial agents might be indicated in certain conditions as an adjunct to this mechanical approach. However, in view of the growing concern about bacterial resistance, alternative approaches have been investigated. Currently, a range of antimicrobial agents and protocols have been used in clinical management, but these remain largely non-validated. This review aimed to evaluate the efficacy of adjunctive antibiotic use in periodontal management and to compare them to recently suggested alternatives. Evidence from in vitro, observational and clinical trial studies suggests efficacy in the use of adjunctive antimicrobials in patients with grade C periodontitis of young age or where the associated risk factors are inconsistent with the amount of bone loss present. Meanwhile, alternative approaches such as photodynamic therapy, bacteriophage therapy and probiotics showed limited supportive evidence, and more studies are warranted to validate their efficiency.

Peri-Implantitis: Application of a Protocol for the Regeneration of Deep Osseous Defects. A Retrospective Case Series

Background and aims: Peri-implantitis is a complex pathology, both in its diagnosis and in the identification of etiological causes. Although we have been studying more and more over the years to try to answer the many questions that remain regarding everything that circulates around this disease which affects implants, nothing has yet been taken as an official consensus regarding its surgical treatment. There are still many proposed protocols, each of which has been shown to have comforting results and promising prospects, but no total predictability. The aim of this case series is to assess the clinical outcomes of a mixed protocol for the regeneration of deep osseous defects. Materials and methods: The data and clinical records of 23 patients, with 29 implants affected by peri-implantitis treated surgically in private practice, were analyzed retrospectively. The method used for the surgical treatment was a mixed protocol of mechanical–chemical decontamination and bone regeneration with bovine xenograft. Results: All patients were followed for at least 2 years, averaging 28.9 months (a range of 24–38 months) with a reduction in the probing depth (PD) at one year from the initial 8.14 ± 1.156 mm to 3.72 ± 0.649 mm, and to 4.14 ± 1.093 mm at the final assessment. The differences between assessment time points were always statistically significant. The data regarding bleeding on probing (BoP) and suppuration also showed a statistically significant reduction at the final time point compared to the baseline. Only one patient, at 24 months, still showed BoP, suppuration, and a PD deeper than 5 mm, indicating a recurrence of the disease compared to the initial improvement of the PD (5 mm) at one year. Conclusions: In conclusion, within the limits of this retrospective analysis, it can be affirmed that this combined mechanical–chemical and regenerative decontamination therapy is effective in the treatment of peri-implantitis.

Microbiome differences in periodontal, peri-implant, and healthy sites: a cross-sectional pilot study

OBJECTIVES

To explore microbial communities associated with health and disease status around teeth and dental implants.

MATERIALS AND METHODS

A total of 10 healthy, 24 periodontitis, and 24 peri-implant sites from 24 patients were sequenced by next-generation sequencing. Microbial DNA was extracted and 16S rRNA gene was amplified. Bioinformatic analyses were performed using quantitative insights into microbial ecology (QIIME), linear discriminant analysis effect size (LEfSE), and STAMP.

RESULTS

Differences in microbial diversity across three types of sites were not statistically significant. Several genera and species were more prevalent in healthy compared with diseased sites, including Lautropia, Rothia and Capnocytophaga and Kingella. Among diseased sites, Peptostreptococcaceae, Dialister, Mongibacterium, Atopobium, and Filifactor were over-represented in peri-implantitis sites, while Bacteroidales was more abundant in periodontitis sites.

CONCLUSIONS

Diseased periodontal and peri-implant sites and corresponding healthy sites have distinct microbiological profiles. These findings suggest that microbial analyses could identify biomarkers for periodontal health and disease and lead to the development of new strategies to improve periodontal health and treat peri-implant and periodontal diseases.

CLINICAL RELEVANCE

The study contributes to improving our understanding of healthy, periodontally affected, and peri-implantitis sites which can improve our ability to diagnose, monitor, and manage these oral conditions.

Effect of repeated ultrasonic instrumentation on single-unit crowns: a laboratory study

OBJECTIVES

This laboratory study aimed to assess the effects of ultrasonic instrumentation, simulating 10 years of supportive periodontal therapy (SPT), on single-unit crowns.

MATERIALS AND METHODS

Standardized crowns were fabricated from porcelain-fused-to-metal (PFM) (n = 12), zirconia (ZrO₂) (n = 12), lithium disilicate (LDS) (n = 12), feldspar ceramic (FSFC) (n = 6), and polymer-infiltrated ceramic network material (PICN) (n = 6). The crowns, luted on PICN abutments with resin-based luting material (RBLM), and if applicable glass ionomer cement (GILC), underwent thermal cycling and trimonthly ultrasonic instrumentation. After 1 and 10 years of simulated SPT, restoration quality assessments were performed, comprising profilometric surface roughness measurements, marginal integrity evaluations, and scores for luting material remnants and visible cracks. The statistical analysis included multiple logistic regressions with nested designs (α = 0.05).

RESULTS

During simulated SPT, bulk fractures (n = 2) and a de-cementation failure (n = 1) of LDS and ZrO₂ crowns were observed. No significant change in roughness was detected after 10 years (p = 0.078). Over time, marginal defects increased (p = 0.010), with PFM crowns showing the highest rate of chippings at sites with a narrow shoulder. Fewer marginal defects were detectable on crowns luted with RBLM compared with GILC (p = 0.005). Luting material remnants decreased during SPT (p < 0.001). Ultrasonic instrumentation caused cracks in most crown materials, in particular at sites with a narrow shoulder and in PFM crowns.

CONCLUSIONS

Repeated ultrasonic instrumentation may damage single-unit crowns. PFM crowns with a narrow, all-ceramic margin are especially prone to defects.

CLINICAL RELEVANCE

Frequent ultrasonic instrumentation of restoration margins of fixed dental prostheses, PFM crowns in particular, ought to be avoided.

Soft Tissue Regeneration at Natural Teeth

This article provides an overview of the best-documented surgical techniques for recession coverage and draws conclusions for the clinician. Use of a connective tissue graft with either coronally advanced flap (CAF) or tunnel is the most predictable technique for the treatment of single and multiple gingival recessions. Long-term results exist only for CAF with/without connective tissue graft providing evidence for long-term stability with only minor relapses. Soft tissue replacement materials and biologics may represent a valuable modality to additionally improve the clinical outcomes obtained with CAF alone or, in certain clinical situations, to serve as an alternative to autogenous tissue.

Efficacy of Adjunctive Antimicrobial Photodynamic Therapy to Mechanical Debridement in the Treatment of Peri-implantitis or Peri-implant Mucositis in Smokers: A Systematic Review and Meta-analysis

This systematic review and meta-analysis aimed to determine whether adjunctive use of antimicrobial photodynamic therapy (a-PDT) in peri-implant diseases improves clinical outcomes in smokers. An electronic search was performed in MEDLINE (through PubMed), Scopus, Cochrane Library, Embase, Web of Science and Google Scholar. The primary outcome measures were bleeding on probing (BOP) and pocket depth (PD). Plaque index (PI) was the secondary outcome. Four RCTs, (188 participants) comprised of 118 cigarette smokers, 38 E-cig smokers and 32 water pipe smokers with follow-up periods ranged from 6 weeks to 6 months were recruited. All trials applied diode laser in one session with wavelengths ranged from 660 to 670 nm. There was a significant difference between mechanical debridement (MD)+a-PDT and MD alone groups in PD (WMD = -1.26 mm, 95% CI: -2.19 to -0.32, P = 0.01) and PI (WMD = -10.60%, 95% CI: -14.46 to -6.74, P < 0.001) at 3-month follow-up. However, a great amount of heterogeneity was observed (PD: χ² = 199.19, I² = 98%, P < 0.001 and PI: χ² = 25.63, I² = 84.4%, P < 0.001). Due to methodological heterogeneity and small number of studies, this systematic review was unable to reach conclusive evidence in regards of adjunctive a-PDT efficacy in improving clinical parameters in smokers.

Efficacy of 0.05% Chlorhexidine and 0.05% Cetylpyridinium Chloride Mouthwash to Eliminate Living Bacteria on In Situ Collected Biofilms: An In Vitro Study

Chlorhexidine (CHX) mouthwashes are frequently used as an adjunctive measure for the treatment of periodontitis and peri-implantitis, as well as in patients on maintenance therapy. However, their prolonged use is associated with several side effects. This study aimed at evaluating if a mouthwash with a reduced concentration of CHX combined with cetylpyridnium chloride (CPC) was as effective as a conventional CHX mouthwash in the reduction in living cells in oral biofilms attached to hydroxyapatite (HA) and micro-rough titanium (Ti) surfaces. Four healthy volunteers wore a customized acrylic appliance containing HA and Ti discs for in situ plaque accumulation. Biofilms were grown on the discs for 24 or 48 h and then randomly exposed for 60 s to: 0.05% CHX + 0.05% CPC, 0.1% CHX (positive control) or sterile saline (negative control). Viability assay and live-dead staining were performed to quantify bacterial viability and to distinguish live and dead cells, respectively. At both time points, contrary to saline, CHX, both alone and in combination with CPC, exhibited high antibacterial properties and induced a significant reduction in biofilm viability. This study demonstrates the potential of mouthwashes containing a low concentration of CHX combined with CPC as effective antibacterial agents for long-term applications with reduced undesired side effects.

What do we know about the mechanisms of action of probiotics on factors involved in the pathogenesis of periodontitis? A scoping review of in vitro studies

OBJECTIVE

Probiotics are increasingly used in oral prevention and treatment conditions, but little is known about their abilities. The aim of this review is to clarify, summarize and disseminate current knowledge about the mode of action of in vitro probiotics on factors involved in the pathogenesis of periodontitis.

METHOD

2495 articles were identified in three databases (Medline, Web of Science, SpringerLink) and 26 studies included in this scoping review.

RESULTS

Twenty-three probiotic species were identified, the majority of which were Lactobacilli or Bifidobacteria. Lactobacillus rhamnosus (30.8 %) and Lactobacillus reuteri (42.3 %) were found to be the two predominantly studied probiotic species and three main mechanisms of action of probiotics could be classified as: (i) modulation of the immuno-inflammatory response, (ii) direct actions of probiotics on periodontopathogens by adhesion or nutritive competitions and/or the secretion of antimicrobial molecules and (iii) indirect actions through environmental modifications. A combination of several probiotic strains seems to be beneficial via synergistic action amplifying the functions of each strain used. However, heterogeneity of the methodologies and probiotic species included in studies leads us to consider the following avenues for future research: (i) implementation of standardized periodontal models as close as possible to in vivo periodontal conditions to identify the functions of each strain for appropriate medication, (ii) updating data about interactions within oral biofilms to identify new candidates and to predict then analyze their behavior within these biofilms.

CONCLUSION

Probiotics may have their place in the response to inter-individual variability in periodontitis, provided that the choice of the probiotic strain or combination of them will be personalized and optimal for each patient.

Success of supportive periodontal therapy in periodontitis patients - A retrospective analysis

Objective

The aim of this retrospective analysis was to evaluate, in adult patients treated for periodontitis, the periodontal stability during supportive periodontal therapy (SPT).

Methods

Data were collected and analyzed retrospectively for periodontitis patients aged ≥36 years who underwent active periodontal therapy (APT) and were following an SPT programme. The stability of the APT success, defined as a probing pocket depth (PPD) of ≤5 mm, was the main outcome parameter. Analyses were performed in which PPD, tooth loss (TL), bleeding on probing (BOP), periodontal epithelium surface area (PESA), and the effects of age, gender, smoking status, and the number of years in SPT were evaluated. The annual TL and BOP of <10% in addition to a PPD of ≤5 mm were considered to be secondary outcome variables.

Results

In total, 993 patients were included, in 36% of whom a PPD ≤5 mm was found at the evaluation of APT. If the outcome was defined as a BOP of <10% in addition to a PPD of ≤5 mm, this was present in only 16% of the patients. During SPT, a small overall increase in clinical parameters for the total population and an annual average TL of 0.15 per patient was observed. Patients of male gender and smokers negatively affected the success of SPT.

Conclusion

The periodontal clinical status remained ‘fairly’ stable during SPT in chronic periodontitis patients aged ≥36 years. Smoking negatively affects the outcome of APT and periodontal stability during SPT.

Ibero-Panamerican Federation of Periodontics Delphi study on the trends in diagnosis and treatment of peri-implant diseases and conditions: A Latin American consensus

BACKGROUND

The social diversity, heterogeneous culture, and inherent economic inequality factors in Latin America (LA) justify conducting a comprehensive analysis on the current status and future trends of peri-implant diseases and conditions. Thus, the aim of this Delphi study was to predict the future trends in the diagnosis and treatment of peri-implant diseases and conditions in LA countries for the year 2030.

METHODS

A Latin American steering committee and group of experts in implant dentistry validated a questionnaire including 64 questions divided into eight sections. The questionnaire was run twice with an interval of 45 days, with the results from the first round made available to all the participants in the second round. The results were expressed in percentages and data was analyzed describing the consensus level reached in each question.

RESULTS

A total of 221 experts were invited to participate in the study and a total 214 (96.8%) completed the two rounds. Moderate (65%-85%) to high consensus (≥ 85%) was reached in 51 questions (79.69%), except in the questions dealing with "prevalence", where no consensus was reached. High and moderate consensus was attained for all the questions in three fields (risk factors and indicators, diagnosis and treatment of peri-implant conditions and deficiencies, and prevention and maintenance).

CONCLUSIONS

The present study has provided relevant and useful information on the predictions in the diagnosis and treatment of peri-implant diseases with a high level of consensus among experts. Nevertheless, there is still a lack of agreement in certain domains.

Prosthodontic Principles in Dental Implantology: Adjustments in a Coronavirus Disease-19 Pandemic-Battered Economy

More patients are requesting fixed prosthesis to replace missing teeth. More than 5 million dental implants are placed annually in the United States. This number will decrease in 2020 owing to the coronavirus disease-19 pandemic. The edentulous patient has a decreased quality of life. Prosthodontic rehabilitation/reconstruction of edentulism improves overall quality of life. Patient-reported outcome measures are subjective reports of patients' perceptions of their oral health status and the impact that it has on their quality of life. This chapter contains a variety of prosthodontic principles for the reader to help satisfy the needs and expectations of the patient.

The occurrence of peri-implant mucositis associated with the shift of submucosal microbiome in patients with a history of periodontitis during the first two years

AIM

To investigate the dynamic changes of peri-implant microbiome in patients with a history of periodontitis and to construct a microbial prediction model.

MATERIALS AND METHODS

The prospective study was performed at one month (T1), one year (T2) and two years (T3) after restoration. Clinical examinations [probing depth (PD), bleeding on probing (BOP), suppuration (SUP)], radiographic examinations and sample collection were conducted at three timepoints. Peri-implant sulcular fluid (PISF) was collected and analysed by 16S rRNA gene sequencing. Generalized linear mixed model (GLMM) was used to identify differences.

RESULTS

Totally, 168 subjects were assessed for eligibility. Twenty-two patients were recruited in the longitudinal study. Eventually, 67 PISF samples from 24 implants of 12 patients were collected and analysed. Peri-implant microbiome showed increasing diversity and complexity over time. Disease-associated genera Porphyromonas, Tannerella, Treponema and Prevotella dramatically increased from T1 to T3. The prediction model for clinical suppuration at T1 showed a high accuracy of 90%.

CONCLUSION

The dysbiosis of peri-implant microbiome increased with time during the two-year observation in patients with a history of periodontitis. Genera of Porphyromonas, Tannerella, Treponema and Prevotella were biomarkers of peri-implant mucositis. Microbiota at the early stage could predict subsequent microbial dysbiosis and clinical suppuration.

Supportive treatment following peri-implantitis surgery: An RCT using titanium curettes or chitosan brushes

AIMS

The aim of this randomized controlled trial was to assess the effect of two maintenance programmes when treatments were performed every third month from six to 18 months following surgical treatment of peri-implantitis.

MATERIALS AND METHODS

At the 6-month post-surgical evaluation, 44 subjects were randomized into groups receiving supportive peri-implant treatment either by the use of titanium curettes or chitosan brushes at implants registered with BoP and PPD >3 mm. Follow-up examinations and supportive therapy were performed 6, 9, 12, 15 and 18 months post-surgically. Clinical and radiographic assessments were made.

RESULTS

The percentage of implants registered with inflammation was high at the 6-month baseline examination (>80% bleeding on probing in both test and control group) and remained high throughout the observation period. Similar observations were made for all clinical parameters, and no significant difference was found between test and control groups.

CONCLUSIONS

In the present study, no statistical significant difference was found when supportive peri-implant treatment was performed with either titanium curettes or chitosan brushes. Within the limits of the study, the results might indicate the need of more effective submucosal cleaning procedures following peri-implant surgery.

Changing the Focus to the Whole Patient instead of One Oral Disease: The Concept of Individualized Prevention

Oral diseases are highly prevalent and a global burden. Accordingly, their prevention appears essential. Recently, different strategies have been developed, mainly focusing on the presence of singular oral diseases or conditions. This article aims to construct a contemporary concept of individualized preventive care in dentistry whereby the focus is switched from viewing oral health in isolation to viewing the patient as a whole. The basis for individualized prevention measures is the case-oriented profile, including the synthesis of risk- and need-oriented parameters. The risk profile comprises different risk factors within the fields of systemic diseases, medications, and lifestyle that inherently pose a potential risk of complications (e.g., infectious endocarditis) and/or oral diseases (e.g., periodontitis). The needs profile includes factors originating from the aspects of oral diseases, dental restorations/appliances, and dental results with a potential risk of pathogenesis (e.g., the de novo development of caries) and/or the potential progression of oral diseases (e.g., an existing caries lesion). Based on these parameters, the general framework and content of prevention measures, as well as the maintenance interval, should be adapted to the individual patient. The implications of this concept might increase the safety, effectiveness, and efficiency of prevention in dental care. A further area of focus is primary prevention, that is, a focus on the preservation of oral health instead of a disease-related approach. However, clinical validation is needed to prove the benefits of the model presented. Individualized prevention promotes a shift from a disease-focused model to a whole-patient-focused model and provides a potential approach for establishing a contemporary concept for preventive care in dentistry.

Tooth survival and clinical outcomes up to 26 years after guided tissue regeneration therapy in deep intra-bony defects: Follow-up investigation of three randomized clinical trials

AIM

To investigate tooth survival and clinical long-term outcomes up to 26 years following guided tissue regeneration (GTR) therapy in deep intra-bony defects.

METHODS

Patients from three prospective clinical split-mouth studies, which investigated the outcomes of GTR therapy, were re-evaluated 21-26 years after surgery independent of the membrane type used, and tooth survival was assessed according to several site-specific and patient-related factors.

RESULTS

About 50 patients contributing 102 defects were available for this long-term follow-up. After up to 26 years (median 23.3 years), 52.9% of the teeth were still in situ. The median survival of the extracted teeth was 13.8 years. Patients with diabetes mellitus and/or smoking history lost significantly more teeth in the long term. Compared to the 1-year situation, there was no new median CAL loss after up to 26 years in the teeth which were still in situ.

CONCLUSIONS

Within the limitations of this study, our data show that more than 50% of the initially seriously diseased teeth were still in situ up to 26 years following GTR therapy despite an overall limited adherence to SPT. In the majority of these teeth, the CAL gain 1 year after GTR could be maintained over this long period.

Role of Dental Implant Homecare in Mucositis and Peri-implantitis Prevention: A Literature Overview

Background:

Correlation between high plaque index and inflammatory lesions around dental implants has been shown and this highlights the importance of patient plaque control. Until now, knowledge of peri-implant home care practices has been based on periodontal devices.

Objective:

The aim of this overview is to identify the presence of scientific evidence that peri-implant homecare plays a role in mucositis and peri-implantitis prevention.

Methods:

Different databases were used in order to detect publications reflecting the inclusion criteria. The search looked into peri-implant homecare studies published from 1991 to 2019 and the terms used for the identification of keywords were: Dental implants, Brush, Interproximal brushing, Interdental brushing, Power toothbrush, Cleaning, Interdental cleaning, Interspace cleaning, Flossing, Super floss, Mouth rinses, Chlorhexidine. The type of studies included in the selection for this structured review were Randomized Clinical Trials, Controlled Clinical Trials, Systematic Reviews, Reviews, Cohort Studies and Clinical cases.

Results:

Seven studies fulfilled all the inclusion criteria: 3 RCTs, one Consensus report, one cohort study, one systematic review and one review. Other 14 studies that partially met the inclusion criteria were analyzed and classified into 3 different levels of evidence: good evidence for RCTs, fair evidence for case control and cohort studies and poor evidence for expert opinion and case report.

Conclusion:

Not much research has been done regarding homecare implant maintenance. Scientific literature seems to show little evidence regarding these practices therefore most of the current knowledge comes from the periodontal literature. Manual and powered toothbrushes, dental floss and interdental brushes seem to be useful in maintaining peri-implant health. The use of antiseptic rinses or gels does not seem to have any beneficial effects.

It can be concluded that to better understand which are the most effective home care practices to prevent mucositis and peri-implantitis in implant-rehabilitated patients, new specific high evidence studies are needed.

Risk factors for recurrence of periodontal disease in patients in maintenance care in a private practice

AIM

To assess periodontal and dental conditions in individuals in maintenance care after periodontal therapy in private practice, and to identify risk factors for recurrence of disease and tooth loss.

MATERIALS AND METHODS

One hundred patients attending a routine recall visit were included. All had been treated for periodontal disease and were in maintenance since ≥ 2 years.

RESULTS

Examinations took place 18.0 (±8.71) years after the start of periodontal therapy. A total of 40.1 ± 22.5 recall visits were registered during this time. 91% of the participants had an initial diagnosis of chronic, 9% of aggressive periodontitis. The average participant was 46 years old and had 26 teeth. 283 of 2,549 initially present teeth were lost, half of them being molars. Periodontal and endo-periodontal complications accounted for only 16 lost teeth. The prevalence of all probing depth (PD) categories decreased significantly. The longer the time, the more frequent the recall visits, and the more was spent during the maintenance phase, the greater was the reduction. Multivariate analysis rendered BMI and smoking as factors influencing number of sites with PD ≥ 4 mm and bleeding on probing.

CONCLUSION

Tooth loss and periodontal tissue damage can be contained over prolonged periods if periodontal disease is treated and patients attend regular maintenance care.

Treatment trends in periodontics

This volume of Periodontology 2000, entitled "Treatment Trends in Periodontics", evaluates the importance of nonsurgical periodontal therapy and defines its role as the key etiologic treatment of the disease. The need for scaling and root planing is mandatory step during the initial phase of therapy, as is self-care by the patient. Only after reevaluation of the outcome achieved by nonsurgical procedures should surgery be considered, and the concept of "critical probing depth" is emphasized. The chapters in this volume discuss different aspects of periodontal surgery, including regeneration and plastic periodontal procedures, and, looking toward the future, cell therapy in periodontics is explored. The impact of periodontal therapy on systemic diseases is reviewed, and the role of occlusion in periodontal disease is revisited and discussed. Topics on implants include their placement in fresh extraction sockets, socket healing with or without implant placement, and research on osseointegration. The important topic of maintenance care of teeth and implants for long-term therapeutic success is thoroughly evaluated, as is the efficacy of dentifrices in oral hygiene. The editors convey a nutshell review of the concepts of what periodontal treatment should entail, based on scientific evidence generated during half-a-century of work in periodontics.