Periodontal therapy

Impact of Periodontitis on Endothelial Risk Dysfunction and Oxidative Stress Improvement in Patients with Cardiovascular Disease

Periodontitis is a multifactorial chronic inflammatory disease that affects the periodontium and overall oral health and is primarily caused by a dysbiotic gingival biofilm, which includes, among others, Gram-negative bacteria such as Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, and Tannerella forsythensis that colonize gingival tissues and that can lead, if not properly treated, to periodontal tissue destruction and tooth loss. In the last few decades, several large-scale epidemiological studies have evidenced that mild and severe forms of periodontitis are strictly bilaterally associated with several cardiovascular diseases (CVDs), stroke, and endothelial dysfunction. Specifically, it is hypothesized that patients with severe periodontitis would have compromised endothelial function, a crucial step in the pathophysiology of atherosclerosis and several CVD forms. In this regard, it was postulated that periodontal treatment would ameliorate endothelial dysfunction, hence bolstering the notion that therapeutic approaches targeted at diminishing cardiovascular risk factors and different forms of periodontal treatment could improve several CVD biomarker outcomes in the short- and long-term in CVD patients. The aim of this review is to update and analyze the link between periodontitis and CVD, focusing on the inflammatory nature of periodontitis and its correlation with CVD, the effects of periodontal therapy on endothelial dysfunction and oxidative stress, and the impact of such therapy on CVD biomarkers and outcomes. The article also discusses future research directions in this field.

Periodontal Pocket Therapy Using a Class IV Dental Diode Laser in Dogs: A Retrospective Analysis

Class IV dental diode lasers have been introduced as a nonsurgical therapy for periodontal pockets in veterinary and human dentistry. This retrospective case series evaluates the use of Class IV dental diode laser therapy for abnormal periodontal pockets in a specialty veterinary dental practice. A hypothesis that the Class IV diode dental laser is a useful adjuvant modality in canine periodontal pocket therapy in the reduction of clinical pocket depth was made. This article discusses and demonstrates diode laser use in periodontal pocket therapy in a specialty veterinary dental practice and reviews the current literature. Inclusion in this study was limited to client-owned dogs with noted periodontal pocketing on any tooth type between 3 and 6 mm, which were treated with closed root planing (RP/C) and laser therapy who returned in 6 to 7 months for recheck of the pockets from the years 2017 to 2020. Twelve patients met the inclusion criteria. A total of 128 periodontal pockets were included in the study. Each periodontal pocket was a case receiving therapy. The mean periodontal pocket depth before the treatment is measured as 3.35 mm. The mean pocket depth of the periodontal pockets following treatment was 0.59 mm. The mean improvement in periodontal pocket depths after diode laser therapy when considering patient and tooth number using linear mixed-effects modeling was 2.63 mm (95% confidence interval [CI]: 1.81-3.46, P < .0001). No statistically significant results were observed for pocket type, as P values were greater than .05.

Influence of Gallic Acid-Containing Mouth Spray on Dental Health and Oral Microbiota of Healthy Dogs: A Pilot Study

The pilot study aimed to investigate the effects of GAMS on oral microbiota in healthy dog subjects. Thirty-eight dogs were recruited and randomly allocated to the placebo (n = 19) and treatment groups (n = 19). The dogs were treated with mouth spray once daily for 42 days. The changes in the gingival index (GI), plaque index (PI), and calculus index (CI) were measured at baseline (day 0) and end of the study (42nd day). The changes in the oral microbial composition of representative dogs (placebo, n = 7; and treatment, n = 7) were also evaluated at baseline and end of the study. Oral microbial composition was assessed by sequencing. The sequences were annotated using the QIIME 2.0^TM. The GI, PI, and CI indexes were reduced after the GAMS usage. The abundance of the commensal bacterial phylum Actinobacteria and Chloroflexi, genera Frederiksenia, and Bergeyella was improved after six weeks of GAMS usage. GAMS reduced the pathogenic bacterial species, including Neisseria sp., Desulfobulbus sp., Capnocytophaga canis, and Corynebacterium mustelae. Moreover, some pathogenic bacterial abundances were increased at the end of the study. All the microbial variations were observed within the group. The inter-group analysis revealed that the changes were unrelated to GAMS usage. Further studies need to be carried out using more experimental subjects to confirm the effectiveness of GAMS. More metagenomic data are required to evidence the GMAS impact on the oral microbiome of healthy dogs.

Revisiting Periodontal Disease in Dogs: How to Manage This New Old Problem?

Periodontal disease (PD) is one of the most prevalent oral inflammatory diseases in dogs. PD onset begins with the formation of a polymicrobial biofilm (dental plaque) on the surface of the teeth, followed by a local host inflammatory response. To manage this disease, several procedures focusing on the prevention and control of dental plaque establishment, as well as on the prevention of local and systemic PD-related consequences, are essential. The removal of dental plaque and the inhibition of its formation can be achieved by a combination of dental hygiene homecare procedures including tooth brushing, the application of different oral products and the use of specific diet and chew toys, and regular professional periodontal procedures. Additionally, in some cases, periodontal surgery may be required to reduce PD progression. Associated with these measures, host modulation therapy, antimicrobial therapy, and other innovative therapeutic options may be useful in PD management. Moreover, PD high prevalence and its relation with potential local and systemic consequences reinforce the need for investment in the development of new preventive measures, treatments, and oral procedures to improve the control of this disease in dogs. Knowledge on the specific guidelines and diversity of the available products and procedures are fundamental to apply the most adequate treatment to each dog with PD.

A polymicrobial biofilm model for testing the antimicrobial potential of a nisin-biogel for canine periodontal disease control

BACKGROUND

Periodontal disease (PD) in dogs is prompted by the establishment of a polymicrobial biofilm at the tooth surface and a subsequent host inflammatory response. Several strategies may be used for PD control, including dental hygiene home care procedures, like toothbrushing, special diet and chew toys that reduce dental plaque accumulation, or professional periodontal treatments. Aiming at PD control, a biogel composed by nisin and guar-gum was previously developed. This work aimed to establish an in vitro model mimicking the PD-associated biofilms and to evaluate the nisin-biogel inhibitory activity against this polymicrobial biofilm by determining its Minimum Biofilm Inhibitory (MBIC) and Eradication Concentrations (MBEC). Bacterial species tested included Neisseria zoodegmatis CCUG 52598T, Corynebacterium canis CCUG 58627T, Porphyromonas cangingivalis DSMZ VPB 4874, Peptostreptococcus canis CCUG 57081 and an Enterococcus faecalis isolate belonging to a collection of oral bacteria obtained from dogs with PD. Before establishing the biofilm, coaggregation between species was determined by optical density measurement after 2 and 24 hours. Nisin-biogel MBIC and MBEC values regarding the polymicrobial biofilm were determined using a modified version of the Calgary biofilm pin lid device, after confirming the presence of the five bacterial species by Fluorescent In Situ Hybridization.

RESULTS

Only 40% of the bacterial dual suspensions were able to coaggregate at 2 hours, but all species tested exhibited a coaggregation percentage higher than 30% at 24 hours. It was possible to establish a 48 h polymicrobial biofilm model composed by the five bacterial species selected. This model was used to determine nisin-biogel MBIC (26.39 ± 5.89 µg/mL) and MBEC (62.5 ± 27.73 µg/mL) values.

CONCLUSIONS

Our results showed that the nisin-biogel can inhibit and eradicate PD multispecies biofilms. As this in vitro model mimics an in vivo periodontal polymicrobial biofilm, our results reinforce the potential of the application of nisin-biogel for canine PD control.

Bone Marrow Mesenchymal Stem Cell-Derived Small Extracellular Vesicles Promote Periodontal Regeneration

Bone marrow mesenchymal stem cell-derived small extracellular vesicles (BMSC-sEVs) can be used as a potential cell-free strategy for periodontal tissue regeneration, and we aim to investigate the effect and possible mechanism of BMSC-sEV in periodontal tissue regeneration in this study. The BMSC-sEV was isolated by the Exosome Isolation™ reagent and identified by transmission electron microscopy, nanoparticle tracking analysis, and Western blotting. The human periodontal ligament cells (hPDLCs) were cocultured with BMSC-sEV in vitro to detect the effects of BMSC-sEV on hPDLC migration, proliferation, and differentiation. The BMSC-sEV loaded by hydrogel was injected into experimental periodontitis rats to verify the therapeutic effect and possible mechanism. The results showed that BMSC-sEVs were 30-150 nm vesicles and expressed the exosome protein CD63 and tumor susceptibility 101 (TSG101), which could promote the migration, proliferation, osteogenic differentiation of hPDLCs. The BMSC-sEV-hydrogel had a therapeutic effect on periodontitis rats. After administration for 4-8 weeks, microcomputed tomography and histological analysis showed that alveolar bone loss, inflammatory infiltration, and collagen destruction in the BMSC-sEV-hydrogel group were less than that in the phosphate-buffered saline (PBS)-hydrogel group and periodontitis group. Further immunohistochemical and immunofluorescent staining revealed that the number of tartrate-resistant acid phosphatase-positive cells and the expression ratio of osteoprotegerin (OPG) and receptor-activator of nuclear factor kappa beta ligand (RANKL) in the BMSC-sEV-hydrogel group were lower than that in the PBS-hydrogel group and periodontitis group, while the expression of transforming growth factor-beta 1 (TGF-β1) and the ratio of macrophage type 2 and macrophage type 1 (M2/M1) were opposite. Therefore, BMSC-sEV can promote the regeneration of periodontal tissues, and that may be partly due to BMSC-sEV involvement in the OPG-RANKL-RANK signaling pathway to regulate the function of osteoclasts and affect the macrophage polarization and TGF-β1 expression to modulate the inflammatory immune response, thereby inhibiting the development of periodontitis and immune damage of periodontal tissue. Impact statement Bone marrow mesenchymal stem cell-derived small extracellular vesicles (BMSCs-sEVs) have been proven to have similar functions to BMSCs, such as promoting the regeneration of heart, liver, kidney, and bone tissue and regulating immune responses. BMSCs are candidate seed cells of periodontal regeneration, but it is unclear about the role of BMSC-sEV on periodontal regeneration. In this study, we explored the effects and possible mechanism of BMSC-sEV on periodontal regeneration. The results of this study provide the evidence of BMSC-sEV as a cell-free strategy for periodontal regeneration.

World Small Animal Veterinary Association Global Dental Guidelines

Dental, oral, and maxillofacial diseases are some of the most common problems in small animal veterinary practice. These conditions create significant pain as well as localized and potentially systemic infection. As such, the World Small Animal Veterinary Association (WSAVA) believes that un- and under treated oral and dental diseases pose a significant animal welfare concern. Dentistry is an area of veterinary medicine which is still widely ignored and is subject to many myths and misconceptions. Effective teaching of veterinary dentistry in the veterinary school is the key to progression in this field of veterinary medicine, and to the improvement of welfare for all our patients globally. These guidelines were developed to provide veterinarians with the information required to understand best practices for dental therapy and create realistic minimum standards of care. Using the three-tiered continuing education system of WSAVA, the guidelines make global equipment and therapeutic recommendations and highlight the anaesthetic and welfare requirements for small animal patients. This document contains information on common oral and dental pathologies, diagnostic procedures (an easily implementable and repeatable scoring system for dental health, dental radiography and radiology) and treatments (periodontal therapy, extractions). Further, there are sections on anaesthesia and pain management for dental procedures, home dental care, nutritional information, and recommendations on the role of the universities in improving veterinary dentistry. A discussion of the deleterious effects of anaesthesia free dentistry (AFD) is included, as this procedure is ineffective at best and damaging at worst. Throughout the document the negative effects of undiagnosed and/or treated dental disease on the health and well-being of our patients, and how this equates to an animal welfare issue, is discussed.

Topical oral 1-tetradecanol complex in the treatment of periodontal diseases in cats

OBJECTIVES

The aim of this study was to evaluate the outcomes of the treatment of chronic periodontal disease with an oral application of tetradecanol complex (1-TDC) in cats.

METHODS

The test group (n = 9) received 1-TDC (525 mg per gel capsule/day) and the placebo group (n = 4) received olive oil (0.25 ml per gel capsule/day) for 6 weeks.

RESULTS

Oral treatment with 1-TDC resulted in significant reductions in all parameters of clinical periodontal disease except tooth mobility at 6 weeks. The 1-TDC group exhibited a statistically significant reduction in pocket depth, clinical attachment loss, gingival index and bleeding on probing after treatment at 6 weeks, whereas the placebo group did not show any significant change.

CONCLUSIONS AND RELEVANCE

Chronic inflammation associated with periodontal diseases leads to periodontal tissue destruction. As a result, modulation of the host response has been included in the treatment protocol for periodontal diseases. Fatty acids present anti-inflammatory properties and are being investigated for use in the treatment and prevention of progressive periodontal diseases.

Potential of two delivery systems for nisin topical application to dental plaque biofilms in dogs

BACKGROUND

Periodontal disease (PD) is caused by the development of a microbial biofilm (dental plaque) in the periodontium, affecting approximately 80% of dogs. Several bacterial species present in the canine oral cavity can be implicated in the development of this disease, including Enterococcus spp. To decrease antibiotic administration, a possible control strategy for dog's enterococcal PD may involve the use of the antimicrobial peptide (AMP) nisin. Nisin's inhibitory activity was evaluated against a collection of previously characterized enterococci obtained from the oral cavity of dogs with PD (n = 20), as well as the potential of a guar-gum gel and a veterinary toothpaste as topical delivery systems for this AMP. The Minimum Inhibitory (MIC) and Bactericidal Concentrations (MBC) and the Minimum Biofilm Eradication (MBEC) and Inhibitory Concentrations (MBIC) were determined for nisin and for the supplemented guar-gum gel. For the supplemented veterinary toothpaste an agar-well diffusion assay was used to evaluate its inhibitory potential.

RESULTS

Nisin was effective against all isolates. Independently of being or not incorporated in the guar-gum gel, its inhibitory activity on biofilms was higher, with MBIC (12.46 ± 5.16 and 13.60 ± 4.31 μg/mL, respectively) and MBEC values (21.87 ± 11.33 and 42.34 ± 16.61 μg/mL) being lower than MIC (24.61 ± 4.64 and 14.90 ± 4.10 μg/mL) and MBC (63.09 ± 13.22 and 66.63 ± 19.55 μg/mL) values. The supplemented toothpaste was also effective, showing inhibitory activity against 95% of the isolates.

CONCLUSIONS

The inhibitory ability of nisin when incorporated in the two delivery systems was maintained or increased, demonstrating the potential of these supplemented vehicles to be applied to PD control in dogs.

Low-power laser irradiation promotes the proliferation and osteogenic differentiation of human periodontal ligament cells via cyclic adenosine monophosphate

Retaining or improving periodontal ligament (PDL) function is crucial for restoring periodontal defects. The aim of this study was to evaluate the physiological effects of low-power laser irradiation (LPLI) on the proliferation and osteogenic differentiation of human PDL (hPDL) cells. Cultured hPDL cells were irradiated (660 nm) daily with doses of 0, 1, 2 or 4 J⋅cm⁻². Cell proliferation was evaluated by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, and the effect of LPLI on osteogenic differentiation was assessed by Alizarin Red S staining and alkaline phosphatase (ALP) activity. Additionally, osteogenic marker gene expression was confirmed by real-time reverse transcription-polymerase chain reaction (RT-PCR). Our data showed that LPLI at a dose of 2 J⋅cm⁻² significantly promoted hPDL cell proliferation at days 3 and 5. In addition, LPLI at energy doses of 2 and 4 J⋅cm⁻² showed potential osteogenic capacity, as it stimulated ALP activity, calcium deposition, and osteogenic gene expression. We also showed that cyclic adenosine monophosphate (cAMP) is a critical regulator of the LPLI-mediated effects on hPDL cells. This study shows that LPLI can promote the proliferation and osteogenic differentiation of hPDL cells. These results suggest the potential use of LPLI in clinical applications for periodontal tissue regeneration.

Periodontal disease immunology: 'double indemnity' in protecting the host

During the last two to three decades our understanding of the immunobiology of periodontal disease has increased exponentially, both with respect to the microbial agents triggering the disease process and the molecular mechanisms of the host engagement maintaining homeostasis or leading to collateral tissue damage. These foundational scientific findings have laid the groundwork for translating cell phenotype, receptor engagement, intracellular signaling pathways and effector functions into a 'picture' of the periodontium as the host responds to the 'danger signals' of the microbial ecology to maintain homeostasis or succumb to a disease process. These findings implicate the chronicity of the local response in attempting to manage the microbial challenge, creating a 'Double Indemnity' in some patients that does not 'insure' health for the periodontium. As importantly, in reflecting the title of this volume of Periodontology 2000, this review attempts to inform the community of how the science of periodontal immunology gestated, how continual probing of the biology of the disease has led to an evolution in our knowledge base and how more recent studies in the postgenomic era are revolutionizing our understanding of disease initiation, progression and resolution. Thus, there has been substantial progress in our understanding of the molecular mechanisms of host-bacteria interactions that result in the clinical presentation and outcomes of destructive periodontitis. The science has embarked from observations of variations in responses related to disease expression with a focus for utilization of the responses in diagnosis and therapeutic outcomes, to current investigations using cutting-edge fundamental biological processes to attempt to model the initiation and progression of soft- and hard-tissue destruction of the periodontium. As importantly, the next era in the immunobiology of periodontal disease will need to engage more sophisticated experimental designs for clinical studies to enable robust translation of basic biologic processes that are in action early in the transition from health to disease, those which stimulate microenvironmental changes that select for a more pathogenic microbial ecology and those that represent a rebalancing of the complex host responses and a resolution of inflammatory tissue destruction.

Evaluation of a dental model for training veterinary students

Periodontal disease has deleterious effects on an animal's health and potentially serious implications for its welfare. Consequently, veterinarians frequently perform routine periodontal treatment in small-animal practice. One would therefore assume that small-animal dentistry would constitute a core component of a veterinary curriculum. However, most practitioners received little or no formal training in dentistry during their veterinary degrees, and the amount of instruction students currently receive is variable, often with limited opportunities to practice. At the Royal Veterinary College, a prototype dental model was developed to address the lack of practical training; it was made using ceramic tiles, silicone sealant, and grout to emulate teeth, gingiva, and calculus, respectively. A study was conducted with third-year veterinary students to compare the outcomes of learning to perform a professional dental cleaning using a model (group A) or a video (group B). Performance was assessed using an objective structured clinical examination. Students in group A scored significantly better than those in group B (p<.001). All students also completed a questionnaire evaluating attitudes toward the use of a dental model in learning dentistry-related skills. All students identified a model as a potentially valuable learning tool to supplement existing teaching methods and facilitate the acquisition of small-animal dentistry skills. The dental model has the potential to equip students with useful, practical skills in a safe and risk-free environment.

Periodontal regeneration using a bilayered PLGA/calcium phosphate construct

The regeneration of tissues affected by periodontal disease is a complex process; it encompasses the formation of bone, cementum and periodontal ligament. We developed a semi-rigid PLGA (polylactide-co-glycolide acid)/CaP (calcium phosphate) bilayered biomaterial construct to promote periodontal regeneration, which has a continuous outer barrier membrane and an inner topographically complex component. Our experimental model compared periodontal prophylaxis alone with prophylaxis and biomaterial implantation in the treatment of class II furcation defects in dogs. Clinical evaluation, micro-computed tomography, histology and backscattered electron imaging were used for data analysis. Healing occurred uneventfully and bone volumetric values, trabecular number and trabecular thickness were all significantly greater in the treated group; while trabecular separation was significantly greater in the control group. New cementum, bone, and periodontal ligament with Sharpey fibre insertions were only seen in the treated group. Although periodontal regeneration has been reported elsewhere, the advantages of employing our bilayered PLGA + CaP construct are twofold: 1)it did not collapse into the defect; and, 2) its inner side was able to retain the blood clot throughout the buccal defect. The result was greater periodontal regeneration than has previously been reported with traditional flexible membranes.