Changes In Periodontal Tissues Research Articles

Radiological, histological and clinical side effects of incisor trimming in rabbits.

Incisor malocclusion in rabbits (Oryctolagus cuniculus) is a common clinical problem seen in general practice. Given that the growth rate is about 2 mm per week, a lack of wear quickly leads to feeding difficulties and soft tissue injuries. Therefore, pathologically elongated incisors must be shortened every three to six weeks. The goal of this study was to assess the potential adverse effects on dental and periodontal tissues associated with the three most commonly used trimming methods: nail cutter, diamond-coated cutting disc and diamond burr. The left mandibular incisor of 28 healthy New Zealand rabbits was subjected to four trimmings with one of the three cutting methods. After the fattening period, the mandibles were collected and both mandibular incisors were investigated on dental radiographs, micro-computed tomography scans and histological sections. Dental and periodontal tissue changes were evaluated. This study allowed a more accurate statement of the potential short-term adverse effects of the three trimming methods. At the clinical level, the nail cutter caused the formation of an irregular occlusal surface with sharp edges. Both engine-drive methods allowed the attainment of a smooth surface but the disc was less accurate. Histological evaluation revealed that the primary modifications, including coronal fractures, periodontal ligament widening and inflammation, reparative osteodentine, paracementosis and biofilm accumulation, were found in the nail cutter group.

Histological changes in the structural components of the gums in lipopolysaccharide periodontitis

Summary. Inflammatory diseases of periodontal tissues are one of the most important problems in dentistry. There is a strong connection between periodontal pathology and inflammatory diseases of the stomach. The aim of the study – to investigate pathomorphological changes in rat periodontal tissues with generalized lipopolysaccharide periodontitis associated with chronic atrophic gastritis. Мaterials and Methods. The experiments were performed on white outbred male rats weighing 160–180 g. 30 animals were used during the work. The tested animals were divided into the following groups: I – intact rats (control); II – animals with a model of generalized lipopolysaccharide periodontitis. For a morphological study of the periodontium, a fragment of the upper jaw was isolated. Histological preparations were studied using an SEOSCAN light microscope. Such classical research methods make it possible to study the structure of tissues, as well as the nature and depth of morphological changes, the sequence of development of destructive and regenerative processes. Results and Discussion. It has been established that with generalized lipopolysaccharide periodontitis, a reorganization of all structural components of the gum tissue occurs. It is manifested by changes in the epithelium of the mucous membrane of the gums, an increase in the stratum corneum, a decrease in the spinous layer, expansion of intercellular spaces, growth of lymphocytic infiltration, swelling of the connective tissue of the mucous membrane, expansion, blood filling of veins and hemocapillaries, cells of the walls of fibrous structures. Conclusions. Concomitant chronic atrophic gastritis significantly aggravates the pathomorphological picture of periodontitis induced in animals by the endotoxin of gram-negative microflora lipopolysaccharide.

The interplay between gingival crevicular fluid microbiome and metabolomic profile in intensively treated people with type 1 diabetes - a combined metagenomic/metabolomic approach cross-sectional study.

This study aimed to assess the gingival crevicular fluid (GCF) microbiome and metabolome of adults with type 1 diabetes (T1D) treated with continuous subcutaneous insulin infusion (CSII). In this cross-sectional study, the GCF of adults with T1D treated with CSII and non-diabetic controls were sampled, and metagenomic/metabolomic analyses were performed. In total, 65 participants with T1D and 45 healthy controls with a mean age of 27.05 ± 5.95 years were investigated. There were 22 cases of mild gingivitis (G) in the T1D group. There were no differences considering the Shannon and Chao indices and β-diversity between people with T1D and G, with T1D without G, and healthy controls. Differential taxa were identified, which were mainly enriched in people with T1D and G. Acetic acid concentration was higher in people with T1D, regardless of the presence of G, than in healthy controls. Propionic acid was higher in people with T1D and G than in healthy controls. Isobutyric and isovaleric acid levels were higher in individuals with T1D and G than in the other two subgroups. The concentration of valeric acid was lower and that of caproic acid was higher in people with T1D (regardless of gingival status) than in healthy controls. The identification of early changes in periodontal tissues by targeting the microbiome and metabolome could potentially enable effective prevention and initial treatment of periodontal disease in people with T1D.

In vivo study of gingival crevicular fluid interleukin 1-beta (IL1-β) and prostaglandin-E2 (PGE-2) levels with pain perception after placement of elastomeric separators with and without low level laser therapy: An in vivo study

Orthodontic tooth movement following application of force features bone remodelling changes in periodontal and dental tissues. These necessary orthodontic tooth movement achieved by numerous orthodontic procedures that evokes pain sensations in patients, such as separator placement, archwire placement and activations. The aim of the study is to compare the levels of interleukin 1-beta and prostaglandin E2 in GCF with pain perception after placement of elastomeric separators with and without low level laser therapy. 12 patients scheduled for orthodontic treatment, were screened test and control. Mesial and distal elastomeric separators flanked the maxillary first molar arch. The experimental side received 20s of Ga Al As, diode laser irradiation at 810 nm, 2 J/cm2, 200 mW power output, while the control tooth did not. GCF was collected from the mesiobuccal and mesiopalatal sides of first molars in the maxillary quadrant before, 1hr, 24 hours, and 48 hours after separator installation from both groups to quantify IL1-b and PGE2. The control and experimental group had IL-1β levels of 18.609 ng/ml (SD = 3.833) and 17.582 ng/ml (SD = 2.425) at the 'Before' time point, with p< 0.001. Significant variations in IL-1β and PGE2 were observed from baseline, with p < 0.001. After 1 hour, IL-1β levels significantly increased to 132.678 ng/ml (SD = 9.628)/ 83.848 ng/ml (SD = 8.833).In the 24-hour interval, IL-1β levels increased dramatically to 185.283 ng/ml (SD = 9.875) and 116.998 ng/ml (SD = 5.680). By 48 hours, IL-1β levels remained high at 157.459 ng/ml (SD = 10.141) and 103.664 ng/ml (SD = 9.662). Low-level laser therapy has been shown to reduce pain perception and decrease inflammatory mediators IL-1β and PGE2 in GCF patients with elastomeric separators. A positive correlation exists between these biomarkers, pain perception, and laser irradiation across all time intervals.

EFFECTIVENESS OF THERAPEUTIC AND PROPHYLACTIC MEASURES IN THE MANAGEMENT OF GENERALISED PERIODONTITIS OF THE INITIAL AND FIRST DEGREE IN PATIENTS WITH ATHEROSCLEROSIS ACCORDING TO PARACLINICAL STUDIES

Summary. In recent years, scientists have been paying great attention to the relationship between dental and general somatic health, where, in particular, they express the opinion that periodontitis may play a role as an independent risk factor for the development of vascular atherosclerosis and its clinical manifestations (coronary heart disease, myocardial infarction, stroke).
 The aim of the study – to evaluate the effectiveness of the proposed therapeutic and prophylactic measures in the management of generalized periodontitis of the initial I degree in patients with atherosclerosis according to paraclinical indices.
 Materials and Methods. The effectiveness of treatment of generalized periodontitis of the initial I degree was evaluated on the basis of the dynamics of hygienic and periodontal indices in 26 patients with atherosclerosis: 15 patients – the main group and 11 patients – the control group. To study the intensity and prevalence of the inflammatory process in the gums, we used a modified method of determining the papillary-marginal-alveolar index by C. Parma. The combined periodontal index proposed by Russel was used to determine the severity of dystrophic-inflammatory changes in periodontal tissues. The loss of epithelial attachment was determined by the method of G.F. Beloklitskaya. The degree of gingival bleeding was determined using the papillary bleeding index (PBI). To determine the degree and nature of bone resorption of the alveolar ridge, the radiological index (Rtg) according to Fush was used. The hygienic condition of the oral cavity was assessed by the Fedorova-Volodkina index. The statistical calculation of the results was performed using Statistica 8.0 (StatSoft, USA) and the statistical functions package of Microsoft Excel 2021.
 Results and Discussion. As a result of our studies, it was found that the use of the proposed therapeutic and prophylactic complex for the management of initial I-degree GP contributed to the improvement of the hygienic state of the oral cavity, which was confirmed by a decrease in the index by 47.58 % 6 months after treatment. Improvement in the clinical condition of periodontal tissues in patients of the main group was confirmed by a decrease in the index scores of the indices: PMA, PBI, HEC, p<0,01, PI, p<0,05, against the background of an increase in the Rtg index, p<0,01, relative to the data before treatment. On the basis of the conducted studies, the effectiveness of the use of our proposed treatment and prevention complex, which included a set of individual hygiene measures, local and general pharmacotherapy, adapted for the successful management of initial I degree GP in patients with atherosclerosis, was proved, and was confirmed by the «stabilization» of the pathological process in 80,0% of the treated patients of the main group against 36,36% of the control group, in whom the treatment of initial I degree GP was carried out according to generally accepted methods. The state of periodontal tissues was objectified as «unchanged» in 20,0% of the main group and 36.36% of the treated control group. «Deterioration» of periodontal tissues was diagnosed only in 27,28 % of patients in the control group.
 Conclusions. Thus, the use of the proposed therapeutic and prophylactic complex for the management of generalized periodontitis of the initial I degree in patients with atherosclerosis contributed to the improvement of the clinical condition of periodontal soft tissues, which was confirmed by the positive dynamics of hygienic and periodontal indices and was characterized by the «stabilization» of the pathological process in 80,00±5,78 % of the treated patients of the main group against 36,36±7,24 % of the control group.

Influence of antiresorptive/antiangiogenic therapy on changes in periodontal and oral tissue structures: a histomorphometrical analysis in rats

ObjectiveThe objective of this study was to investigate the influence of various antiresorptive and antiangiogenic medications on morphological changes in periodontal and oral tissue structures.Materials and methodsFifty-five Wistar rats randomly received dual application (i.e., at baseline and after 12-weeks) one of the following medications: (1) amino-bisphosphonate [zoledronate (Zo)], (2) RANKL inhibitor [denosumab (De)], (3) antiangiogenic [bevacizumab (Be)], (4) Zo + Be, (5) De + Be or (6) no medication [Control (Co)]. Periodontal and oral tissue biopsies were obtained at 17 (n = 21 animals, Phase 1, (De = 3, De + Be = 3, Zo = 5, Be = 3, Zo + Be = 2, Co = 5) and 29 (n = 34 animals, (De = 8, De + Be = 6, Zo = 2, Be = 7, Zo + Be = 4, Co = 7, Phase 2) weeks after the second drug application. The following outcomes were histomorphometrically assessed: periodontal space width in the coronal (PLS-C, mm) and apical sections (PLS- A), number of empty alveolar bone lacunae in the coronal, apical sections and at the apex at respective tooth sites (EL – C, EL- A, EL- Ap), mucosal thickness at edentulous alveolar ridge areas (MT, mm), and, when present, associated areas of inflammatory cell infiltrates (ICI, mm2).ResultsComparable mean PLS-C, PLS-A, ET-A, ET-C, ET-Ap, and MT values were observed in all experimental groups after Phases 1 and 2. The presence of ICI was identified in 3 animals in the Co group (Phase 1: 1, Phase 2: 2), and 17 animals in the test groups (Phase 1: 4; Phase 2: 14). The estimated ICI surface area was significantly higher in the Zo + Be group, followed by the Zo and Be groups compared to that measured in the Co group. The time (i.e., Phases 1 and 2) was not found to be a predictor for the extent of the ICI area. In all groups, the EL-C, EL-A, and EL-Ap values were significantly higher after Phase 2 compared to those assessed after Phase 1. The MT values were significantly reduced in all groups after Phase 2 compared to those measured after Phase 1.ConclusionsThe present evaluation was not able to find any morphological effects of different antiresorptive and antiangiogenic medications on periodontal and oral tissue structures. The presence of inflammatory cell infiltrates was more frequently observed in the animals administered with antiresorptive and antiangiogenic medications as well as combinations thereof.Clinical relevanceAdministration of antiresorptive and antiangiogenic medications may be capable of inducing inflammatory reactions in periodontal tissues.

Age Related Senescence, Apoptosis, and Inflammation Profiles in Periodontal Ligament Cells from Canine Teeth.

The periapical tissues, including periodontal ligament cells (PDLCs) play an important role in repairing the surrounding tissue of the teeth. A decrease in the regenerative potentiality of resident stem cells (PDLCs) has been suggested to be attributed to the decline of pulp regeneration. Therefore, examining the functional changes in periodontal tissue and cells that occur during the aging process is necessary. The changes in the cementum extract (CE) and PDLCs isolated from young and aged dog teeth were evaluated. PDLCs growth rate, senescence markers, p16 and p21, and proinflammatory cytokines, IL-6, IL-1β, and TNF-α, were analyzed by RT-PCR. Bax, an apoptosis marker, Bcl-2, a marker for cell survival, and IL-6 were examined by Western blot analyses to detect their variance expression in the CE. Our results demonstrated that aged PDLCs exhibit a low growth rate and an increased expression of p16; however, no change has been demonstrated in the expression of p21. The chronic inflammatory molecules, IL-6 and TNF-α, were significantly upregulated compared to young PDLCs. Western blot analyses showed decreased expression of Bcl-2 in the CE of the aged tooth (p < 0.001). Taken together, aging influences the functional changes of PDLCs and CE and increases senescence, chronic inflammation, and apoptosis markers. As a result, donor age is a key factor influencing the utilization of PDLCs for tooth regeneration.

Diabetes mellitus promotes susceptibility to periodontitis-novel insight into the molecular mechanisms.

Diabetes mellitus is a main risk factor for periodontitis, but until now, the underlying molecular mechanisms remain unclear. Diabetes can increase the pathogenicity of the periodontal microbiota and the inflammatory/host immune response of the periodontium. Hyperglycemia induces reactive oxygen species (ROS) production and enhances oxidative stress (OS), exacerbating periodontal tissue destruction. Furthermore, the alveolar bone resorption damage and the epigenetic changes in periodontal tissue induced by diabetes may also contribute to periodontitis. We will review the latest clinical data on the evidence of diabetes promoting the susceptibility of periodontitis from epidemiological, molecular mechanistic, and potential therapeutic targets and discuss the possible molecular mechanistic targets, focusing in particular on novel data on inflammatory/host immune response and OS. Understanding the intertwined pathogenesis of diabetes mellitus and periodontitis can explain the cross-interference between endocrine metabolic and inflammatory diseases better, provide a theoretical basis for new systemic holistic treatment, and promote interprofessional collaboration between endocrine physicians and dentists.

Digital and clinical approach to quantifying periodontal tissue changes after crown lengthening surgery: A case series pilot study

Crown lengthening surgery is a common periodontal procedure carried out to increase the amount of tooth exposure for aesthetic or restorative purposes. It is crucial for clinicians to understand the effect of crown lengthening surgery on the periodontal tissues to prevent relapse or over treatment. Even though various clinical parameters have been used by researchers in the past to quantify the amount of suprastructure exposed, the use of digital technology has not been widely adopted. The aim of this case series was to evaluate the changes in periodontal tissue after crown lengthening surgery with both clinical and digital approaches. This case series included five patients who underwent surgery at the Postgraduate Periodontics Clinic at the University of Otago over the period of six months. Clinical parameters such as probing depth, gingival recession, keratinised tissue height, plaque accumulation, gingival inflammation, crown height, gingival phenotype, and bone height were measured with a customised probing stent at baseline and 1-, 3-, and 6-month post-surgery. Digital impressions were also taken along with the clinical parameters to measure the volumetric changes. Most significant changes were observed in crown exposure, gingival recession and bone levels, followed by probing depth reduction for treated sites. Minimal changes were seen for the width of keratinised tissues, plaque levels and gingival scores. Volumetric changes were only significantly reduced after 6 months of healing. This case series found that crown lengthening resulted in an increase in tooth exposure and a reduction in tissue volume. Volumetric changes measured through sequential digital impressions were also comparable to clinical findings.

Mineralizing activity of periodontal bone tissue of rats with experimental diabetes

Background. To determine the effect of diabetes on the state of periodontal bone tissue.&#x0D; Methods. In rats, diabetes mellitus of the first type (DM1) was reproduced with the help of alloxan and diabetes mellitus of the second type (DM2) with the help of protamine. The activity of alkaline (ALP) and acid (ACP) phosphatases, calcium content, protein and elastase activity were determined in periodontal bone tissue. The level of biochemical markers of inflammation and protective systems was determined in the blood serum and in the gums. The mineralizing activity of bone tissue was determined by the ALP/ACP ratio.&#x0D; Results. It was established that the mineralizing activity of periodontal bones is significantly higher in males and increases with age. The reproduction of DM1 and DM2 in rats caused a significant decrease in the mineralizing activity of periodontal bone tissue and insignificant changes in the level of calcium and protein. In rats with diabetes, an inflammatory process develops in the gums (increase in the level of elastase) against the background of a decrease in the level of markers of protective systems (catalase and lysozyme).&#x0D; Conclusion. A decrease in the level of mineralizing activity of periodontal bone tissue under conditions of diabetes can be the reason for the development of diabetic periodontitis.

Submicroscopic changes of periodontal components under experimental periodontitis combined with hypothyroidism

Endocrine disorders are an extremely urgent medical and social problem of modern society. Changes in the thyroid gland activity cause violations of the regulation of metabolism in periodontal tissues. Expressed clinical signs of periodontal tissues inflammation directly depend on the severity and duration of disorders of the functional state of the thyroid gland. The purpose of this study was to describe the ultrastructural changes of periodontal tissues under the conditions of experimental periodontitis in combination with hypothyroidism. To model periodontitis lipopolysaccharide was injected into the gum tissue of rats. The experimental thyroid gland hypofunction was simulated using intragastrical administration of mercazolyl. To confirm the state of hypothyroidism we determined the content of free thyroxine, free triiodothyronine and thyroid-stimulating hormone. Submicroscopic studies revealed profound destructive-degenerative changes in all components of the periodontium. Changes in periodontal tissues in experimental hypothyroidism are stereotyped: dystrophic, atrophic and destructive changes in parenchymal structures, mucinous edema of the stroma, mild reparative processes. Thus, it can be concluded that during experimental periodontitis in combination with hypothyroidism, there are violations of the functioning of all the components of the vessels of the periodontal microcirculatory channel. This is manifested by damage and deformation of the blood vessel wall with desquamation of the endothelium, edema, thinning of the basement membrane, stasis, thrombosis and spasm. Also, significant destruction and lysis of fibrous structures and components of the connective tissue amorphous substance in the lamina propria of the attached and free part of gums and periodontium are characteristic.

Expression of spleen macrophages in a mouse model of alveolar bone resorption periodontitis.

It has been shown that macrophages can be endotoxin-tolerant under the stimulation of continuous endotoxin of Porphyromonas gingivalis. Macrophage transforms into M2-type which inhibits inflammation, and its pro-inflammatory cytokine secretion is reduced to avoid the tissue damaged by inflammation. This experiment established the corresponding animal model to explore the relative number, phenotypic proportion, and function of spleen macrophages in mice with chronic periodontitis. Twenty 16-week-old mice were randomly divided into a true ligation group (LFP group) and a pseudo-ligation group (LFC group). The periodontitis in the LFP group was induced by experimental ligation, and the LFC group was treated as a control. After 10 days of ligation, the maxilla was taken, IHC and HE staining were performed to observe the pathological changes of periodontal tissues, and IHC staining was performed to observe the RANKL/OPG ratio. Spleen mononuclear cells were isolated and counted. The ratio of M1 and M2 phenotypes was determined by fluorescence-activated cell sorting (FACS) in the spleen. The relative expression levels of macrophage-associated inflammatory cytokine TNF-a, IL-1β and anti-inflammatory cytokine IL-10 mRNA were detected by real-time PCR. Compared with the control group (LFC:M2/M110.04%), the M2 ratio among spleen mature macrophages in the periodontitis group (LFP: M2/M135.86%) was significantly increased (P<0.01) in the spleen. The proportion of M1 macrophages was not significantly different, and the ratio of M1/M2 was significantly decreased (P<0.05) in the spleen. But the expression level of M1-type macrophage inflammatory factor TNF-a mRNA was inclined. Chronic periodontitis can up-regulate the proportion of M2 macrophages, decrease the ratio of macrophage phenotype M1/M2, and incline the expression of pro-inflammatory factor TNF-a mRNA.

Age- and sex-related differences of periodontal bone resorption, cognitive function, and immune state in APP/PS1 murine model of Alzheimer’s disease

BackgroundThe existence of an interconnected mechanism between cognitive disorders and periodontitis has been confirmed by mounting evidence. However, the role of age or sex differences in this mechanism has been less studied. This study aims to investigate sex and age differences in the characterization of periodontal bone tissue, immune state and cognitive function in amyloid precursor protein/presenilin 1(APP/PS1) murine model of Alzheimer’s disease (AD).MethodsThree- and twelve-month-old male and female APP/PS1 transgenic mice and wild-type (WT) littermates were used in this study. The Morris water maze (MWM) was used to assess cognitive function. The bone microarchitecture of the posterior maxillary alveolar bone was evaluated by microcomputed tomography (micro-CT). Pathological changes in periodontal bone tissue were observed by histological chemistry. The proportions of helper T cells1 (Th1), Th2, Th17 and regulatory T cells (Tregs) in the peripheral blood mononuclear cells (PBMCs) and brain samples were assessed by flow cytometry.ResultsThe learning ability and spatial memory of 12-month-old APP/PS1 mice was severely damaged. The changes in cognitive function were only correlated with age and genotype, regardless of sex. The 12-month-old APP/PS1 female mice exhibited markedly periodontal bone degeneration, evidenced by the decreased bone volume/total volume (BV/TV), trabecular thickness (Tb.Th), and bone mineral density (BMD), and the increased trabecular separation (Tb.Sp). The altered periodontal bone microarchitecture was associated with genotype, age and females. The flow cytometry data showed the increased Th1 and Th17 cells and the decreased Th2 cells in the brain and PBMC samples of 12-month-old APP/PS1 mice, compared to age- and sex-matched WT mice. However, there was no statistical correlation between age or sex and this immune state.ConclusionsOur data emphasize that age and sex are important variables to consider in evaluating periodontal bone tissue of APP/PS1 mice, and the cognitive impairment is more related to age. In addition, immune dysregulation (Th1, Th2, and Th17 cells) was found in the brain tissue and PBMCs of APP/PS1 mice, but this alteration of immune state was not statistically correlated with sex or age.

THE IMPACT OF ORTHODONTIC TREATMENT ON THE PERIODONTAL STATUS OF PATIENTS

Today, the frequency of dental and jaw anomalies and the need for their correction is extremely high. Orthodontic treatment has a direct impact on the state of the apparatus that supports and retains the teeth; this requires timely detection of periodontal diseases and their therapy in order to save the teeth and successfully correct the bite.&#x0D; The purpose of this work is to review and analyze modern professional literature on the impact of orthodontic treatment of maxillofacial anomalies on the periodontal status of patients, in particular pathogenetic mechanisms of the development of periodontal diseases and features of their clinical course in this category of patients.&#x0D; The study has demonstrated the use of various types of orthodontic appliances for the treatment of maxillofacial anomalies is accompanied by the deterioration of hygienic status, a decrease in the local immune response, dysbiotic changes in periodontal tissues, hemodynamic and microcirculatory disorders and loss of bone tissue. This causes the rapid development and progression of inflammatory diseases of periodontal tissues such as catarrhal and hypertrophic gingivitis, as well as generalized periodontitis in young and working-age individuals. Therefore, the analysis of this problem is relevant and necessary for deeper understanding of the pathogenesis of the development of this pathology in persons having orthodontic treatment, for its timely diagnosis and prevention.&#x0D; The in-depth analysis of scientific literature on the issue enables to systematize and understand the main pathogenetic mechanisms of the development of periodontal diseases in patients during orthodontic treatment. Both the negative multi-vector effect of orthodontic appliances on the periodontal status of patients due to the deterioration of hygienic indicators and the increase of microbial contamination in the early stages of treatment, as well as the positive role in stabilizing the state of supporting tissues in the long term, were noted.

Effect of obesity on tooth movement using an orthodontic device and changes in inflammatory cytokines, periodontal tissues, and orofacial pain.

This study aimed to investigate the effect of obesity prospectively on tooth movement via an orthodontic device and changes in inflammatory cytokines, periodontal tissues, and orofacial pain. Prospective design in which data was gathered at baseline T0, 1 hour, 24 hours, and 1 week after the application of fixed orthodontic appliances. The total sample size was 60 participants aged between 12 to 18 years and divided into 2 groups based on the inclusion and exclusion criteria. Anthropometrical estimation was made using a bioimpedance meter. A clinical assessment was performed before the application of fixed appliance bonding (T0) one hour after bonding (T1), after 24 hours (T2), and finally after one week (T3). At T0 little irregularity index was assessed, gingival crevicular fluid (GCF) was collected and periodontal examination including probing depth (PD), gingival bleeding (GB), and the presence or absence of calculus were measured. Orofacial pain was assessed at three levels: 1 hours, 24 hours, and 1 week after application of fixed orthodontics using a visual analog scale. For inter-group comparison, Mann-Whitney and t-tests were used and for interphase, comparison cluster analysis was performed. The level of significance was p<0.05. The participants in obese groups were significantly higher in terms of weight, BMI, WHR, FM, and BF than in the non-obese group (p<0.05). Obese participants had significantly more PD 4-5 mm (0.64±0.23 mm) and significantly higher BoP than non-obese participants (0.13±0.10 mm). Little's irregularity index at T0 and T3 showed no significant difference among obese and non-obese participants. The inflammatory cytokines level of IL-β was higher in the obese group compared to non-obese groups. The intensity of orofacial pain was higher in obese participants after 24 hours along with high levels of IL-β pro-inflammatory cytokines before and during orthodontic treatment. No difference was noted in tooth movement in both obese and non-obese during orthodontic treatment in the first week.

The effects of smoking on genotoxic and histopathologic damage in exfoliated oral epithelial cells and the periodontium: A cross-sectional study.

Smoking negatively affects the prognosis of periodontal disease by impairing tissue healing. While micronucleus is the most popular parameter for demonstrating DNA damage, inflammatory cell and vascular densities are the most evaluated parameters for determining histopathologic changes in the periodontium. This study aimed to study the effects of periodontitis and cigarette smoking on genotoxic changes in exfoliated oral epithelial cells and histopathologic changes in periodontal tissue. A cross-sectional study was conducted between November 2018 and July 2019 at a dental university hospital in Turkey, and registered as NCT05484765. Eighty systemically healthy subjects were divided into four groups according to periodontal status and smoking habits: 20 smokers with generalized periodontitis (SGP), 20 nonsmokers with generalized periodontitis (NGP), 20 smokers with healthy periodontium (SHP), and 20 nonsmokers with healthy periodontium (NHP). For each study participant, full-mouth clinical periodontal parameters (CPPs) were measured, smear samples were taken from buccal and gingival mucosa, and periodontal tissue was biopsied from the maxillary molars. Cytogenetic and histopathologic assays (primary and secondary outcomes) were conducted using Feulgen reaction and hematoxylin-eosin staining, respectively. The mean CPPs of healthy periodontium groups were lower than generalized periodontitis groups. No significant differences were found between other groups regarding CPPs. Buccal micronuclei counts in groups decreased with the highest to lowest counts occurring in the order SGP > SHP > NGP > NHP. Gingival micronuclei counts in groups decreased from SGP > SHP > NGP = NHP. The most intense inflammatory cell and vascular densities occurred in SGP and NGP groups, respectively; and the mildest values were in healthy periodontium groups. Histopathological damage score decreased significantly by group in order SGP > NGP > SHP > NHP. The synergy arising from the combination of smoking and periodontitis exposures exacerbates genotoxic and histopathologic damage in oral cells and the periodontium.

КЛИНИКО-РЕНТГЕНОЛОГИЧЕСКИЙ АНАЛИЗ СТРУКТУР ПАРОДОНТА ПРИ АНАТОМО-ФУНКЦИОНАЛЬНЫХ НАРУШЕНИЯХ МУКОГИНГИВАЛЬНОГО КОМПЛЕКСА

Subject. Anatomical and functional disorders of the mucogingival complex.&#x0D; Objectives. To evaluate microcirculatory, clinical and radiological changes in periodontal tissues in various variants of mucogingival complex disorders.&#x0D; Methodology. The study was conducted at the Department of Therapeutic Dentistry of ASMU. In the course of the study, 80 patients (49 women, 31 men) aged 18 to 35 years were examined with a ratio of dentition close to orthognathic bite in the presence of maximum occlusion. Three groups were formed depending on the anatomical and functional state of the mucogingival complex. In the clinical part of the study, an objective assessment of the condition of periodontal tissues was carried out on the basis of a dental examination with a comprehensive analysis of the periodontal status. The X-ray examination included the analysis and description of cone-beam computed tomograms for patients of clinical groups. To assess microcirculation in periodontal tissues, the method of ultrasonic Dopplerography with functional probe breakdown was used.&#x0D; Results. In the studied groups, the level of oral hygiene was characterized as good, and the indicators of hygiene indices did not differ significantly, periodontal indices indicated the absence or minimal degree of inflammation in periodontal tissues. Carrying out a functional tension test made it possible to divide patients into subgroups according to the type of reaction: normal, compensated, subcompensated, decompensated. According to the results of the study of CBCT in the comparison group, pathological changes in the bone tissue of the alveolar process of the studied areas were not recorded, in patients of the first clinical group, in most cases (80.2%), pathological changes in the bone tissue of the alveolar process were not observed, in the rest (19.8%), a low level of alveolar bone was noted. In patients of the second clinical group, the phenomena of osteoporosis and an increase in the distance from the dental enamel-cement border to the edge of the outer cortical plate were recorded.&#x0D; Conclusions. X-ray changes in bone tissue most often corresponded to the already existing clinical symptoms of periodontal tissue damage against the background of mucogingival pathology. The predictors of prenosological diagnosis in anatomical and functional disorders of the mucogingival complex were changes in microcirculation indicators.

Assessment of Effect of Intra-pocket Delivery of Metronidazole Loaded NTrimethyl Quaternary Ammonium Chitosan Nanoparticles in Treatment of Periodontal Disease

Background:Conventional drugs like metronidazole for periodontitis has shown several drawbacks. So based on in-vitro and acute toxicity study of metronidazole loaded n-trimethyl quaternary ammonium chitosan nanoparticles (NTMET NPs), animal studies was carried out to proof enhancement of activities over periodontitis.Objectives:To assess the effect of nanoparticles through an intra-pocket drug delivery on body weight, food consumption, clinical signs, gingival index, tooth mobility, inflammatory changes in periodontal tissues, and serum analysis that leads into gingival damage, connective tissues and alveolar bone resorption.Method:P. gingivalis and ligature induced periodontitis model was used to evaluate the effect of drug in rats.Results:periodontitis was successfully induced by using P. gingivalis and ligature induced periodontitis model in rats. It reflect elevated gingival index, tooth mobility, inflammatory changes in tissues, IL-6, TNF- ɑ, and IL -1β when compared to control group and NTMET NPs treated groups. It was also observed that the damage caused to gingival tissues and resorption of alveolar bone was improved by using NTMET NPs.Conclusion:Based on present findings, we can conclude that NTMET NPs at a dose of 1.8 &amp; 3.6 mg/ml has significant action on periodontal tissues and was able to reverse the effect of P. gingivalis as well as gingival damage and tooth mobility in rats at an administered dose, which are comparable to the IC50 value of a drug. The findings of the current study provide scientific preclinical data to support its clinical use for periodontitis via intra pocket drug delivery route.

Remodeling of the periodontal ligament and alveolar bone during axial tooth movement in mice with type 1 diabetes.

To observe the elongation of the axial tooth movement in the unopposed rodent molar model with type 1 diabetes mellitus and explore the pathological changes of periodontal ligament and alveolar bone, and their correlation with tooth axial movement. The 80 C57BL/6J mice were randomly divided into the streptozotocin(STZ)-injected group (n = 50) and the control group (n = 30). Mice in the streptozotocin(STZ)-injected group were injected intraperitoneal with streptozotocin (STZ), and mice in the control group were given intraperitoneal injection of equal doses of sodium citrate buffer. Thirty mice were randomly selected from the successful models as the T1DM group. The right maxillary molar teeth of mice were extracted under anesthesia, and allowed mandibular molars to super-erupt. Mice were sacrificed at 0, 3, 6,9, and 12 days. Tooth elongation and bone mineral density (BMD) were evaluated by micro-CT analysis(0,and 12 days mice). Conventional HE staining, Masson staining and TRAP staining were used to observe the changes in periodontal tissue(0, 3, 6, 9, and 12 days mice). The expression differences of SPARC, FGF9, BMP4, NOGGIN, and type I collagen were analyzed by RT-qPCR. After 12 days of tooth extraction, our data showed significant super-eruption of mandibular mouse molars of the two groups. The amount of molar super-eruption in the T1DM group was 0.055mm( ± 0.014mm), and in the control group was 0.157( ± 0.017mm). The elongation of the T1DM mice was less than that of the control mice(P<0.001). It was observed that the osteoclasts and BMD increased gradually in both groups over time. Compared with the control group, the collagen arrangement was more disordered, the number of osteoclasts was higher (P<0.05), and the increase of bone mineral density was lower(2.180 ± 0.007g/cm3 vs. 2.204 ± 0.006g/cm3, P<0.001) in the T1DM group. The relative expression of SPARC, FGF9, BMP4, and type I collagen in the two groups increased with the extension of tooth extraction time while NOGGIN decreased. The relative expression of all of SPARC, FGF9, BMP4, and type I collagen in the T1DM group were significantly lower, and the expression of NOGGIN was higher than that in the control group (P<0.05). The axial tooth movement was inhibited in type 1 diabetic mice. The result may be associated with the changes of periodontal ligament osteoclastogenic effects and alveolar bone remodeling regulated by the extracellular matrix and osteogenesis-related factors.

Evaluation of morphological, histological, and immune-related cellular changes in ligature-induced experimental periodontitis in mice

Background/purposeThe ligature-induced periodontitis model is an effective approach to induce inflammation and bone loss similar to that of human periodontitis. Previous clinical and in vitro studies have shown the involvement of lymphocytes in periodontitis, while, the local and systemic profile of immune cells associated with periodontitis in the ligature-induced periodontitis model in mice remains unclear. Materials and methodsExperimental periodontitis was constructed in mice by ligating around the maxillary second molars for 14 and 28 days, respectively. Alveolar bone loss was assessed by micro-computed tomography (micro-CT). Hematoxylin and eosin (H&E) and tartrate-resistant acid phosphatase (TRAP) staining were used to evaluate the histological changes in the periodontal tissues. B and T cells in the cervical lymph nodes, spleen, and peripheral blood were analyzed by flow cytometry. ResultsThe 14-day ligation effectively induced significant periodontal inflammation and alveolar bone loss in C57BL/6J mice, which were progressive and maintained for a relatively long-term period until day 28. In addition, CD3+ T cells and CD19+ B cells were the dominant population in both health and disease, and the B cell population within the cervical lymph nodes (LN) increased significantly under periodontitis condition, while, no significant differences of the T and B cell population among the spleen and peripheral blood were observed. ConclusionThe ligature-induced periodontitis mice model was established to perform a longitudinal assessment of changes in periodontal tissues morphologically and histologically, meanwhile, explore the local and systemic changes of the predominant immune-associated cells.