Cause Of Tooth Loss Research Articles

Transcriptional regulation of human amelotin gene by interleukin-1β.

One of the major causes of tooth loss is chronic inflammation of the periodontium, the tissues surrounding the tooth. Amelotin (AMTN) is a tooth enamel protein which is expressed in maturation‐stage ameloblasts and also in the internal basal lamina of junctional epithelium, a unique epithelial structure attached to the tooth surface which protects against the constant microbiological challenge to the periodontium. Localization of AMTN suggests that its function could be involved in the dentogingival attachment. The purpose of this study was to investigate the effect of interleukin‐1β (IL‐1β) on AMTN gene transcription in human gingival epithelial Ca9‐22 cells. IL‐1β increased AMTN mRNA and protein levels at 3 h, and the levels reached maximum at 6 and 12 h. IL‐1β induced luciferase activities of human AMTN gene promoter constructs (−211, −353, −501, −769, and −950AMTN), but these activities were partially inhibited in −353AMTN constructs that included 3‐bp mutations in CCAAT/enhancer binding protein 1 (C/EBP1), C/EBP2, and Ying Yang 1 (YY1) elements. Transcriptional activities induced by IL‐1β were abrogated by protein kinase A (PKA), tyrosine kinase, mitogen‐activated protein kinase kinase (MEK1/2), and phosphatidylinositol 3‐kinase (PI3K) inhibitors. Gel shift and ChIP assays showed that IL‐1β increased C/EBPβ binding to C/EBP1 and C/EBP2, and YY1 binding to YY1 elements after 3 h, and that these DNA–protein interactions were inhibited by PKA, tyrosine kinase, MEK1/2, and PI3K inhibitors. These results demonstrated that IL‐1β increases AMTN gene transcription in human gingival epithelial cells mediated through C/EBP1, C/EBP2, and YY1 elements in the human AMTN gene promoter.

Mechanical adaptation of trabecular bone morphology in the mammalian mandible

Alveolar bone, together with the underlying trabecular bone, fulfils an important role in providing structural support against masticatory forces. Diseases such as osteoporosis or periodontitis cause alveolar bone resorption which weakens this structural support and is a major cause of tooth loss. However, the functional relationship between alveolar bone remodelling within the molar region and masticatory forces is not well understood. This study investigated this relationship by comparing mammalian species with different diets and functional loading (Felis catus, Cercocebus atys, Homo sapiens, Sus scrofa, Oryctolagus cuniculus, Ovis aries). We performed histomorphometric analyses of trabecular bone morphology (bone volume fraction, trabecular thickness and trabecular spacing) and quantified the variation of bone and tooth root volumes along the tooth row. A principal component analysis and non-parametric MANOVA showed statistically significant differences in trabecular bone morphology between species with contrasting functional loading, but these differences were not seen in sub-adult specimens. Our results support a strong, but complex link between masticatory function and trabecular bone morphology. Further understanding of a potential functional relationship could aid the diagnosis and treatment of mandibular diseases causing alveolar bone resorption, and guide the design and evaluation of dental implants.

Three-dimensional Inflammatory Human Tissue Equivalents of Gingiva

Periodontal diseases (such as gingivitis and periodontitis) are the leading causes of tooth loss in adults. Inflammation in gingiva is the fundamental physiopathology of periodontal diseases. Current experimental models of periodontal diseases have been established in various types of animals. However, the physiopathology of animal models is different from that of humans, making it difficult to analyze cellular and molecular mechanisms and evaluate new medicines for periodontal diseases. Here, we present a detailed protocol for reconstructing human inflammatory tissue equivalents of gingiva (iGTE) in vitro. We first build human tissue equivalents of gingiva (GTE) by utilizing two types of human cells, including human gingival fibroblasts (HGF) and human skin epidermal keratinocytes (HaCaT), under three-dimensional conditions. We create a wound model by using a tissue puncher to punch a hole in the GTE. Next, human THP-1 monocytes mixed with collagen gel are injected into the hole in the GTE. By adimistration of 10 ng/mL phorbol 12-myristate 13-acetate (PMA) for 72 h, THP-1 cells differentiated into macrophages to form inflammatory foci in GTE (iGTE) (IGTE also can be stumilated with 2 µg/mL of lipopolysaccharides (LPS) for 48 h to initiate inflammation). IGTE is the first in vitro model of inflammatory gingiva using human cells with a three-dimensional architecture. IGTE reflects major pathological changes (immunocytes activition, intracellular interactions among fibryoblasts, epithelial cells, monocytes and macrophages) in periodontal diseases. GTE, wounded GTE, and iGTE can be used as versatile tools to study wound healing, tissue regeneration, inflammation, cell-cell interaction, and screen potential medicines for periodontal diseases.

Antibacterial and Anti-inflammatory Potential of Morus alba Stem Extract.

Background:Periodontitis, a chronic inflammatory disease, is the leading cause of tooth loss in adults. Evidence for the anti inflammatory activity of M. alba Stem Extract (MSE) in periodontal disease is limited.Objective:The study aimed to investigate the inhibitory effect of MSE on the growth of periodontopathic bacteria and expression of interleukin (IL)-6 and IL-8 in Porphyromonas gingivalis Lipopolysaccharide (LPS)-stimulated human Periodontal Ligament (hPDL) fibroblasts.Methods:The antimicrobial activities of MSE were tested against P. gingivalis and Aggregatibacter actinomycetemcomitans by the disk diffusion, the minimum inhibitory concentration and the minimal bactericidal concentration methods. Cytotoxicity of P. gingivalis LPS and MSE on hPDL fibroblasts was determined by MTS assay. The expression of cytokines (IL-6 and IL-8) mRNA and proteins in hPDL fibroblasts was measured using the reverse transcription-qPCR and enzyme-linked immunosorbent assay, respectively.Results: MSE exhibited antibacterial activities against P. gingivalis and A. actinomycetemcomitans with the zones of inhibition of 10.00 ± 0.33 mm and 17.33 ± 0.58 mm, respectively. MIC and MBC values for MSE against P. gingivalis were 62.5 μg/ml. The MIC and MBC values against A. actinomycetemcomitans were 250 μg/mL and 500 μg/ml, respectively. P. gingivalis LPS was shown to mediate the expression of pro-inflammatory cytokines in hPDL fibroblasts. However, treatment with MSE concentrations of 2.5 and 5.0 μg/ml significantly suppressed P. gingivalis LPS-induced IL-6 and IL-8 mRNA and protein expression (p< 0.05).Conclusion: The present study demonstrates that MSE has antibacterial activity against two putative periodontal pathogens. MSE suppressed IL-6 and IL-8 expression in P. gingivalis LPS-stimulated hPDL fibroblasts, indicating a possible anti-inflammatory effect. Thus, it is a potential adjunctive agent for the treatment of periodontitis.

Automatic quantification framework to detect cracks in teeth.

Studies show that cracked teeth are the third most common cause for tooth loss in industrialized countries. If detected early and accurately, patients can retain their teeth for a longer time. Most cracks are not detected early because of the discontinuous symptoms and lack of good diagnostic tools. Currently used imaging modalities like Cone Beam Computed Tomography (CBCT) and intraoral radiography often have low sensitivity and do not show cracks clearly. This paper introduces a novel method that can detect, quantify, and localize cracks automatically in high resolution CBCT (hr-CBCT) scans of teeth using steerable wavelets and learning methods. These initial results were created using hr-CBCT scans of a set of healthy teeth and of teeth with simulated longitudinal cracks. The cracks were simulated using multiple orientations. The crack detection was trained on the most significant wavelet coefficients at each scale using a bagged classifier of Support Vector Machines. Our results show high discriminative specificity and sensitivity of this method. The framework aims to be automatic, reproducible, and open-source. Future work will focus on the clinical validation of the proposed techniques on different types of cracks ex-vivo. We believe that this work will ultimately lead to improved tracking and detection of cracks allowing for longer lasting healthy teeth.

Comparison of the Effects of Local Injection and Oral Intake of Diclofenac and Atorvastatin in Alveolar Bone Density Assessed with CT in Experimental Periodontitis in Rat

Objectives The first cause of tooth loss in developed countries is periodontitis. Chronic periodontitis is the most common form of periodontitis and it is characterized by loss of periodontal attachment, destruction of alveolar bone and eventual loss of teeth. Atorvastatin is a statin drug used for the treatment of high cholesterol. Statins can stop the inflammatory process by inhibiting the cholesterol pathway. Diclofenac is an NSAID with anti-inflammatory, anti-pyretic and analgesic effects. Its primary mechanism is through the inhibition of prostaglandins synthesis by the inhibition of the cyclooxygenase enzyme (COX). The purpose of this study is to compare the effects of local injected and oral intake of Diclofenac and atorvastatin on alveolar bone density measured in HUs with the use of a CT scan in a periodontitis-induced model in rats.Methods Thirty rats were randomly divided into 6 groups of 5 rats each. Ligatures were placed around the left second maxillary molar to induce periodontitis for 10 days. Administration of 12.5 mg/kg of oral atorvastatin (group 1), 0.25 mg/kg of injectable atorvastatin (group 2), 7.5mg/kg of oral Diclofenac (group 3), 6.25mg/kg of injectable Diclofenac (group 4), the oral solvent without medicine as oral control (groups 5), and the injectable solvent without medicine as injectable control (group 6). In each group, the right side of maxilla was considered as control group (without ligature and drug interaction). At day eleven, the rats were sacrificed and the maxillary bone was separated from the soft tissue and fixed in 4% formalin. The prepared samples were then radiologically evaluated to determine the bone density with CT in fixed exposure conditions.Results There was a statistically significant difference between the alveolar bone density of the oral atorvastatin group and the oral Diclofenac (P = 0.006). There was no statistical significant difference in alveolar bone density between the injectable atorvastatin and the injectable Diclofenac groups (P=0.228).Conclusion Both atorvastatin and Diclofenac have shown better results when assessing bone density in a periodontitis rat model as compared to controls. Additionally, Diclofenac has been shown to be more effective at both oral and injectable administrations as compared with atorvastatin in the prevention of loss of bone density in a rat model with periodontitis.

Prevalence of gingivitis and calculus in 12-year-old Puerto Ricans: a cross-sectional study

BackgroundGingivitis is a common oral health problem. Untreated gingivitis may progress to periodontitis, a common cause of tooth loss. The prevalence of gingivitis and calculus among Puerto Rican children is unknown. Understanding this prevalence can support early public health preventative strategies. This study aims to estimate the prevalence of gingivitis and calculus among 12-year-old Puerto Ricans by health region and to explore differences in distribution by school type (proxy for socio-economic status) and gender.MethodsA probability-based sample of 113 schools was selected proportional to enrollment size and stratified by health region, school type, and gender. Two trained examiners evaluated the presence of gingivitis and both supragingival and subgingival dental calculus. Gingivitis was defined as the presence of gingival bleeding upon gentle probing (BOP) in at least one site, and the extent of the problem was classified according to the percentage of teeth whose gingiva presented BOP (limited: 25–49% of the teeth tested; extensive: >50% of teeth tested). Logistic and linear regression models, adjusted for health regions, were used to compare gingivitis and calculus prevalence and extent between genders and school types.ResultsGingivitis was found in 80.41% of the 1586 children evaluated. Urban-public schoolchildren had a slightly higher prevalence (83.24%) compared to private (79.15%, p = 0.16); those in rural-public (77.59%) and private schools had similar prevalence (p = 0.15). Extensive gingivitis was present in 60.81% of all children. The mean percentage of sites presenting BOP (BOP%) was 17.79%. Rural and urban public schoolchildren presented significantly higher BOP% compared to children from private schools (p = 0.0005, p = 0.002, respectively). Dental calculus was detected in 61.59% of the sample, boys presenting significantly higher (p = 0.005) total and supragingival calculus. Rural-public schoolchildren had a significantly higher prevalence of subgingival calculus compared to private schoolchildren (p = 0.02).ConclusionsGingivitis prevalence is higher among 12-year-old Puerto Ricans compared to data reported for U.S. adolescents. Public schoolchildren presented significantly higher BOP% sites compared to private schoolchildren. Boys presented a significantly higher total and supragingival calculus prevalence than girls. Oral health disparities related to gender and school type were identified by this study. Studies exploring the reasons for these disparities are recommended.

Dermatoglyphic patterns in children with dental caries: An In vivo Study

Background: Dental caries is the predominant cause of tooth loss in children and young adults. Mutans streptococci are the principal etiological agents of dental caries, of which Streptococcus mutans (SM) and Streptococcus sobrinus are most important in terms of human caries. Genetic factors also contribute to dental caries of which dermatoglyphics is one. Aim: The aim of the study was to explore the unique relationship between genetic component (dermatoglyphics) and dental components (dental caries, salivary pH, SM level) and to identify children at particular risk of dental decay. Settings and Design: One hundred children, 6–12 years of age, were selected and divided into two groups: Group 1 (children with dental caries, subject group) and Group 2 (children without dental caries, control group). Methods: Dermatoglyphic patterns were recorded using a digital scanner (CanoScan LiDE), and dental caries status was recorded with “decayed-extracted-filled teeth” index for primary teeth and “decayed-missing-filled teeth” index for permanent teeth. Salivary pH was determined using pH meter strips. SM level was estimated by microbial culture of collected saliva samples. Statistical Analysis: Mann–Whitney test, Wilcoxon test, and Z-test were applied. Results and Conclusion: (1) Subject group had a decreased frequency of loops, whereas control group had increased frequency of loop pattern on palmer digits (P < 0.001). (2) Subject group had a low salivary pH toward normal and control group had high salivary pH values toward normal (P < 0.001). (3) Subject group had high SM level as compared to control group (P < 0.001). Therefore, there exists a relationship between genetic component (dermatoglyphics) and dental component (dental caries, salivary pH, and SM level).

Diagnosis of aggressive periodontitis: A dilemma?

Periodontitis is one of the leading causes of tooth loss in the adult population. This disease can be classified into various categories, and one of the most destructive amongst them is aggressive periodontitis (AgP). The incidence of AgP is lower than other types of periodontitis. However, it affects young individuals and can cause severe destruction of tooth-supporting structures including tooth loss if left untreated. The current classification for diagnosing periodontal disease was established by the American Academy of Periodontology (AAP) in 1999. This classification provided strict guidelines to aid in AgP diagnosis. These include three main factors: systemically healthy individual, rapid loss of clinical attachment, and familial aggregation. In spite of these specific guidelines, AgP diagnosis is often missed clinically due to various reasons. There is still a vast variation in the diagnostic criteria for identifying AgP and not all practitioners utilize the AAP guidelines for their diagnosis. Furthermore, the definition of the disease might be changing in the future to better represent the current understanding of the disease. Since early diagnosis and prompt treatment is key in treating these patients, it is important to have calibration in the diagnosis process. This review aims to identify sources of variation and ambiguity in diagnosing AgP among dental practitioners. For this purpose, we have conducted an extensive literature search and outlined the various diagnostic aids for AgP patients reported in the literature. Understanding and correcting these variations can simplify the diagnostic process leading to faster treatment of patients affected with AgP. This review also emphasizes the importance of minimizing the bias in identifying patients with AgP and highlights the best tools for this purpose.

Anti-inflammatory effect of ATB-352, a H2S −releasing ketoprofen derivative, on lipopolysaccharide-induced periodontitis in rats

Periodontal disease is the most common cause of tooth loss in humans, is an inflammatory disease initiated by oral microbial biofilm. Given the involvement of the inflammatory pathway in this type of pathology, the main pharmacological strategy for the treatment of periodontitis, is the inhibition of the inflammatory process in order to prevent tissue destruction and bone resorption, a condition associated with a painful state. To do this, the best class of drugs are Non-steroidal anti-inflammatory drugs (NSAIDs), however, the presence of side effects, especially at the gastrointestinal tract, limits their use for long-term therapy. Recently, some evidence shows that derivatives of NSAIDs capable of releasing hydrogen sulphide exhibit lower collateral effects, particularly at the gastric level. In fact, H2S is an endogenous gaseous mediator with a cytoprotective role at the gastric level. In this study, we have compared the protective effects of ketoprofen with ATB-352, a hydrogen sulfide-releasing derivative of ketoprofen, in an experimental model of periodontitis in rat. Periodontitis was induced by a single intragingival injection of 1 μl LPS (10 μg/μl), Our results show that 14 h after intragingival injection of LPS, there was a high tissue damage associated with bone resorption, and in gingivomucosal tissues there was a significant expression of NF-kb p65 and pro-inflammatory cytokine as well as a higher expression of COX-2 and iNOS, activation of the apoptotic process, and also increased levels of NGF expression, often associated with a higher nociceptive perception. Treatment with ATB-352 at the dose of 20mg\\kg, was able to reduce the inflammatory process associated with intragingival LPS injection and also had a positive effect on bone resorption and tissue damage.

Effects of local and systemic Atorvastatin on inflammation and alveolar bone loss in experimental periodontitis in rats

Background The first cause of tooth loss in developed countries is periodontitis and mostly occurs in people over 40 years old.Atorvastatin is a statin drug class, which has a revolutionary impact on the treatment of high cholesterol and also stimulates bone morphogenic protein which has osteogenic potential. The aim of this study was to evaluate the effect of local and systemic Atorvastatin in the treatment of periodontitis.Materials and Methods Forty eight Sprague Dawley rats were randomly divided into six groups of eight in each; experimental periodontitis was induced by ligature in five of them in each group daily (1) systemic Atorvastatin 12.5 mg/kg (2) systemic solvent (3) local Atorvastatin 0.25 mg/kg (4) local solvent (5) no drug was administered and group (6) left non-ligated, and rats were sacrificed on 11th day.Histopathological analysis on periodontal tissue; malondialdehyde (MDA) and superoxide dismutase (SOD) tests on serum were performed to investigate bone loss and inflammation. The statistical tests for MDA and SOD samples were one-way ANOVA with Duncan post-hoc whereas in histopathological samples nonparametric Kruskal–Wallis and Mann–Whitney tests were used.Results Although local injection and oral administration of Atorvastatin significantly decreased alveolar bone loss and serum MDA levels, no significant difference in their effectiveness was observed. Serum SOD levels were not significantly changed in all administered groups. P-value < 0.05.Conclusion In this study, both local injection and oral forms of Atorvastatin decreased inflammation and bone loss in periodontitis. However, no significant difference in their effectiveness was detected. However, local injection is superior to oral form due to effective lower dose.

Stemodia maritima L. Extract Decreases Inflammation, Oxidative Stress, and Alveolar Bone Loss in an Experimental Periodontitis Rat Model.

Periodontitis is very prevalent worldwide and is one of the major causes of tooth loss in adults. About 80% of the worldwide population use medicinal plants for their health care. Stemodia maritima L. (S. maritima) antioxidant and antimicrobial effects in vitro as well as anti-inflammatory properties. Herein, the potential therapeutic effect of S. maritima was assessed in rats subjected to experimental periodontitis (EP). EP was induced in female Wistar rats by nylon thread ligature around 2nd upper left molars for 11 days. Animals received (per os) S. maritima (0.2; 1 or 5 mg/kg) or vehicle (saline + DMSO) 1 h before ligature and then once daily for 11 days. The naive group had no manipulation. After this time-point, the animals were terminally anesthetized, and the maxillae were removed for morphometric and histological analyzes (HE). Gingival tissues were dissected to cytokine levels detection (TNF-α, IL1-β, CINC-1, and IL-10), enzymes superoxide dismutase (SOD), and catalase (CAT) analysis, as well as gene expression (TNF-α, IL-1β, RANK, and iNOS) by qRT-PCR. Systemic parameters (weight variation, plasma levels of hepatic enzymes aspartate aminotransferase (AST) and alanine aminotransferase (ALT), creatinine, total alkaline phosphatase (TALP), and bone alkaline phosphatase (BALP) were performed. Histological analysis of the stomach, liver, kidney, and heart was also performed. S. maritima (5 mg/kg) decreased alveolar bone loss, TNF-α and CINC-1 gingival levels, oxidative stress, and transcription of TNF-α, IL1-β, RANK, and iNOS genes. It elevated both BALP activity and IL-10 gingival levels. The animals showed no any signs of toxicity. In conclusion, S. maritima reduced pro-inflammatory cytokine production, oxidative stress, and alveolar bone loss in a pre-clinical trial of periodontitis. S. maritima is a potential tool for controlling the development of periodontitis.

Risk factors for post-operative complications after procedures for autologous bone augmentation from different donor sites

AimThe aim of this study has been to identify risk factors for post-operative complications after grafting bone from different donor sites prior to implant placement. Material and methodsThe study encompassed 279 patients who underwent autologous bone augmentations in a 2-stage procedure, harvested from three intraoral and one extraoral donor sites, as well as sinus floor elevations prior to implant placement. The following complications were recorded: soft tissue dehiscence; wound infection; bone graft exposure; sensory disturbance; sinusitis symptoms; haemorrhage; graft failure; implant failure. Complications were correlated with: patient age; smoking status; history of gingivitis/periodontitis; cause of tooth loss; jaw area; dental situation; sinus membrane perforation; surgeons' experience. Results279 patients underwent 456 augmentation procedures, involving 546 sites. 436 grafts were successful. 525 implants were inserted into 436 augmented sites in 273 patients. 20 grafts were lost due to complications. 2 implants were removed before prosthetic restoration. 2 implants were lost within 2 years after placement. Age (p = 0.0009, Odds Ratio = 2.44), smoking (p < 0.0001, Odds Ratio = 2.47), Approximal Plaque Index (p < 0.0001, Odds Ratio = 6.64), Sulcus Bleeding Index (p < 0.0001, Odds Ratio = 39.06) and dental situation (p < 0.0001) were significantly correlated with higher post-operative morbidity. Cause of tooth loss (p = 0.7399), jaw area (p = 0.6725), sinus membrane perforation (p = 0.0762) and surgeons' experience (p = 0.0939) did not influence complication rates. ConclusionsPatients over 40 years old, smokers, a history of periodontitis, and augmentation in tooth gaps involving more than one tooth represent a significantly increased risk of there being post-operative complications compared with patients younger than 40 years old, non-smokers, no history of periodontitis, only a single-tooth gap, or free-end arch situations.

Tooth Loss in Patients under Periodontal Maintenance in a Private Practice: A Retrospective Study.

The aim of the present study was to evaluate the incidence and causes of tooth loss in periodontal subjects from a private practice in Brazil. Two trained examiners extracted data from the records of subjects who sought periodontal treatment from 1980 to 2013. Only records of patients who completed the non-surgical periodontal treatment and had at least one visit for maintenance were included. Data were analyzed by chi-square test, Student's t-test, Kaplan-Meier survival curve and Cox regression. A total of 3,319 records were reviewed and 737 records included (58.6% women, mean age of 46.6±13.0 years at the beginning of the treatment). Maintenance period ranged from 1 to 33 years (7.4±6 years). During this period, 202 individuals (27.4%) lost 360 teeth, 47.5% of losses within the first five years (n=171). Non-compliers lost more teeth than compliers (p<0.001), respectively 211 and 149 teeth. Regarding reasons of tooth loss, 84 individuals lost 38% of the teeth from periodontal disease progression (n=137). Survival analysis showed that most patients lost only one tooth from periodontal disease, and differences in the survival rates between compliers and non-compliers were observed following the second tooth loss. Approximately one-third of tooth losses was related to periodontal disease progression, and there was stability in time of the proportion of losses from disease progression and other reasons. Therefore, it is possible to conclude that compliant patients in a private practice lose fewer teeth than do non-compliers. Among compliers, periodontal disease progression was not the main cause of tooth loss.

Advances in macrophage function and its anti-inflammatory and proresolving activity and role in periodontitis development

Macrophage plays an important role in human innate immune system. It has powerful functions, such as recognition, phagocytosis, and bacteria and foreign body removal. Periodontitis, which is a chronic infectious disease characterized by gum inflammation and bone loss, is a major cause of tooth loss in adults. Several studies demonstrated that periodontal tissue destruction is caused by the host immune response defending against infections. As an important part of host immune response, macrophage is also involved in periodontitis pathogenesis. Recently, anti-inflammatory and proresolving activities of macrophage was discovered. Thus, the complex function of macrophage in the occurrence, development, and resolution of inflammation and its potential role in periodontitis were reviewed.

Diabetes Enhances IL-17 Expression and Alters the Oral Microbiome to Increase Its Pathogenicity

Diabetes is a risk factor for periodontitis, an inflammatory bone disorder and the greatest cause of tooth loss in adults. Diabetes has a significant impact on the gut microbiota; however, studies in the oral cavity have been inconclusive. By 16S rRNA sequencing, we show here that diabetes causes a shift in oral bacterial composition and, by transfer to germ-free mice, that the oral microbiota of diabetic mice is more pathogenic. Furthermore, treatment with IL-17 antibody decreases the pathogenicity of the oral microbiota in diabetic mice; when transferred to recipient germ-free mice, oral microbiota from IL-17-treated donors induced reduced neutrophil recruitment, reduced IL-6 and RANKL, and less bone resorption. Thus, diabetes-enhanced IL-17 alters the oral microbiota and renders it more pathogenic. Our findings provide a mechanistic basis to better understand how diabetes can increase the risk and severity of tooth loss.

Design, manufacture and test of a dental camera using fluorescence technique

Dental caries is a major oral health problem in most industrialised countries and is still a major cause of tooth loss. The early diagnostics of caries is of great importance for children and adults to facilitate the treatment and prevention of the diseases. In this study, a fluorescence camera was designed and manufactured for this purpose. This device includes a 380-nm LED, which stimulates porphyrins - metabolic products of the life cycle of caries-inducing bacteria to emit fluorescence, and a compact camera recording fluorescence images in real time. The device is connected to computer via usb cable. An archiving software helps save shots as image or video. The weight and size of this device are suitable for the visual inspection in oral cavity and can be used in daily dental practice. The test results showed that this fluorescence camera can detect some types of carious lesions including dental plaque, dental caries, hidden caries and early caries. Besides, this tool has a number of advantages such as noninvasiveness, safety (non-ionizing radiation), mobility, rapid test time, and economical.

Tooth loss and liver cancer incidence in a Finnish cohort.

Periodontal disease, a major cause of tooth loss in adults, may have systemic effects and has been associated with higher risk of several cancer types. However, the associations of periodontal disease or tooth loss with liver cancer have only been examined prospectively in two studies, neither of which had sufficient statistical power. In addition, no studies assessed the potential confounding by viral hepatitis or Helicobacter pylori infection status. In this study, we examined the association between tooth loss and primary liver cancer incidence in a prospective cohort of Finnish male smokers (n=29,096). We used Cox proportional hazards models to calculate multivariable-adjusted hazard ratios (HRs) and 95% CIs. As a sensitivity analysis, we conducted a nested case-control study within the original cohort to assess confounding by hepatitis B or C virus infection and seropositivity of H. pylori. A total of 213 incident primary liver cancers occurred during a mean follow-up of 17years. Among these cases, having 11-31 permanent teeth lost (HR 1.42, 95% CI 1.01-1.98) or all 32 teeth lost (HR 1.45, 95% CI 1.00-2.10) was each associated with higher risk of liver cancer, compared to those having 0-10 teeth lost. Adjusting for H. pylori seropositivity yielded a small attenuation of the effect estimate. Greater number of teeth lost was associated with higher risk of primary liver cancer in our study. The role of periodontal infection in the development of liver cancer warrants further investigation.

Abstract A13: Tooth loss, liver cancer incidence, and chronic liver disease mortality in the ATBC study

Abstract Background: Periodontal disease, a common disorder of the tissue surrounding and supporting the teeth, is a major cause of tooth loss in adults. Periodontal infection by oral microorganisms may have systemic effects and has been associated with several types of cancer. However, its association with liver cancer has only been examined in two prospective studies, both of which had very small number of liver cancer cases (n &amp;lt; 20). Methods: We examined the association of tooth loss, as a proxy measure of periodontal infection, with primary liver cancer incidence and chronic liver disease mortality in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) study, a prospective cohort of male Finnish smokers (n = 29,096). Number of permanent teeth lost was assessed at study baseline (1985-1988). We used Cox proportional hazards models to calculate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). As a sensitivity analysis, we conducted a nested case-control study to assess confounding by hepatitis B or C virus (HBV or HCV) infection and seropositivity of Helicobacter pylori. Results: A total of 213 incident primary liver cancers occurred during a mean follow-up of 17 years. Having 11-31 permanent teeth lost was associated with a 42% higher risk of liver cancer (HR=1.42, 95% CI: 1.01-1.98), and having all 32 teeth lost was associated with a 45% higher risk of liver cancer (HR=1.45, 95% CI: 1.00-2.10), compared to having 0-10 teeth lost. In the sensitivity analysis, adjusting for Helicobacter pylori seropositivity yielded a modest attenuation of the effect estimate, whereas adjustment for HBV or HCV did not materially change the results. No consistent pattern was observed for liver disease mortality (n = 250 deaths). Conclusions: In this study, greater number of teeth lost was associated with higher risk of primary liver cancer. Further investigations are warranted to clarify the role of periodontal infection in hepatocarcinogenesis and to determine the utility of tooth loss as a predictor of liver cancer development. Citation Format: Baiyu Yang, Jessica L. Petrick, Christian C. Abnet, Barry I. Graubard, Stephanie J. Weinstein, Satu Männistö, Demetrius Albanes, Katherine A. McGlynn. Tooth loss, liver cancer incidence, and chronic liver disease mortality in the ATBC study. [abstract]. In: Proceedings of the AACR Special Conference: Improving Cancer Risk Prediction for Prevention and Early Detection; Nov 16-19, 2016; Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(5 Suppl):Abstract nr A13.

Global epidemiology of dental caries and severe periodontitis - a comprehensive review.

Dental caries and periodontitis are the most common oral diseases and major causes of tooth loss. To perform a review of global prevalence and incidence of dental caries and periodontitis. Inclusion and exclusion criteria were developed. MEDLINE database and EMBASE database were used to search for eligible publications using keywords and MeSH terms. Additionally, WHO databank was used for obtaining dental caries information and PUBMED for a search on trends of dental caries prevalence and severity. Over the last four decades, the prevalence and severity of dentine carious lesions among 5- and 12-year-olds have declined; the decay-component is very high, with the lowest prevalence among 12-year-olds in high-income countries, which also had the lowest prevalence among 35- to 44-year-olds; and the number of retained teeth has increased around the globe. The prevalence of periodontitis is high, with approximately 10% of the global population affected by severe periodontitis. Study heterogeneity and methodological issues hamper comparisons across studies and over time. While the prevalence of dental caries has decreased, the disease is prevalent in all age groups. The prevalence of periodontitis is high. There is insufficient evidence to conclude that the prevalence of periodontitis has changed over time.