Analysis of the nano and microstructures of the cervical cementum and saliva in periodontitis: A pilot study

ObjectivesDuring the progression of periodontitis, the structures of the cementum and saliva are altered due to pathological changes in the environment. This study aimed to analyze the nanostructures of the cervical cementum and saliva in patients with periodontitis.MethodsPatients with periodontitis (n = 10) and periodontally healthy controls (n = 8) were included. Single-rooted teeth with indications for extraction were obtained from individuals. The cervical-thirds of the roots were sectioned transversely to obtain 1 mm thick sections. Unstimulated whole saliva samples were collected from each individual. The nanostructures of the cementum and saliva were analyzed using small and wide-angle X-ray scattering methods.ResultsThe mean radius and distance values of the cementum nanoparticles in the periodontitis and control groups were 368 Å and 1152 Å, and 377 Å and 1186 Å, respectively. The mean radius and distance values of the saliva nanoparticles in the periodontitis and control groups were 425 Å and 1359 Å, and 468 Å and 1452 Å, respectively. More wide-angle X-ray scattering profile peaks were observed in the cementum of the controls. Similarities were observed between the 3D profiles of the cementum and the saliva nanoparticles.ConclusionsAccording to the results of the present study, (i) the cementum and saliva nanoparticles were of similar size in periodontitis and healthy controls, (ii) the cementum was more crystalline according to the (002) crystallographic plane in controls, and (iii) the similarities in the 3D-profile of the cementum and saliva nanoparticles suggest some interactions between them in the sulcus/periodontal pocket at the nanolevel.     

Extractions in kidney transplant recipients: A prospective observational pilot study

BackgroundThe authors undertook a prospective study to determine whether kidney transplant recipients had an increased risk of developing complications, such as local acute infection, alveolitis, increased bleeding, pain, and delayed healing, after tooth extraction.MethodsThe authors selected patients who underwent kidney transplants more than 6 months ago (study group) and patients who had not (control group) older than 18 years who needed to undergo extraction of erupted teeth. The same oral surgeon performed all tooth extractions while the patients were under local anesthesia. Another blind researcher examined the patients 3, 7, and 21 days after tooth extraction. The first end point was occurrence of complications (local acute infection, alveolitis, increased bleeding), and the second end point was socket reepithelialization on day 21.ResultsForty-five tooth extractions were performed on 38 study group participants and 61 on 57 control group participants. There was no statistical difference between the groups regarding the incidence of any complication or delayed socket epithelialization.ConclusionsThe results of this pilot study suggest that there is no difference in postoperative healing after tooth extractions between stable kidney transplant patients and control patients.Practical ImplicationsThis is the first prospective study assessing the frequency of postoperative complications after tooth extraction in kidney transplant recipients.This clinical trial was registered at ClinicalTrials.gov. The registration number is NCT02547753.     

Localization of phospholipid-related signal molecules in salivary glands of rodents: A review

BackgroundIn the 1950s, Hokin conducted initial studies on phosphoinositide turnover/cycle in salivary glandular cells. From these studies, the idea emerged that receptor-mediated changes in intramembranous levels of phosphoinositides represent an early step in the stimulus-response pathway. Based on this idea and the general view that knowledge of the exact localization of a given endogenous molecule in cells in situ is important for understanding its functional significance, we have reviewed available information about the localization of several representative phosphoinositide-signaling molecules in the salivary glands in situ in mice.HighlightWe focused on phosphatidylinositol 4-kinase, phosphatidylinositol 4 phosphate 5-kinase α, β, γ, phospholipase Cβ, muscarinic cholinoceptors 1 and 3, diacylglycerol kinase ζ, phospholipase D1 and 2, ADP-ribosylation factor 6 and its exchange factors for Arf6, and cannabinoid receptors. These molecules individually exhibit differential localization in a spatiotemporal manner in the exocrine glands, making it possible to deduce their functional significance, such as their involvement in secretion and cell differentiation.ConclusionAlthough phosphoinositide-signaling molecules whose in situ localization in glandular cells has been clarified are still limited, the obtained information on their localization suggests that their functional significance is more valuable in glandular ducts than in acini. It thus suggests the necessity of greater attention to the ducts in their physio-pharmacological analyses. The purpose of this review is to encourage more in situ localization studies of phosphoinositide-signaling molecules with an aim to further understand their possible involvement in the pathogenesis of salivary gland diseases.     

Comparison of treatment outcomes and time efficiency between a digital complete denture and conventional complete denture: A pilot study

BackgroundThe authors of this study aimed to compare the treatment outcomes and time efficiency between digital and conventional complete denture restorations and propose suggestions for clinical use.MethodsThe authors used digital (functionally suitable digital complete denture [FSD]) and conventional complete denture restorations to make 2 dentures each for 10 edentulous patients. All the operations of both techniques before denture delivery were completed in the first 4 visits, and then 2 dentures were delivered successively for the patients. The clinical and laboratory times were recorded to evaluate the time efficiency; treatment outcomes were evaluated via scoring the denture satisfaction of the dentist and patients in a double-blind manner.ResultsThe satisfaction scores of FSDs (7.6-9.6 [dentist's scores], 8.4-10 [patients' scores]) were higher than those of conventional dentures (7.2-9.7 [dentist's score], 7.4-9.8 [patients' scores]), but there were no significant differences. The clinical and laboratory operation times of the FSD group were less than those of the conventional group, saving an average of 28.0 minutes and 64.3 minutes in the clinic and laboratory, respectively.ConclusionsFSD technology can improve the efficiency of clinical and laboratory operations and shorten the manufacturing cycle of dentures. The occlusion stability of FSDs was statistically better than that of traditional dentures, but there was no statistical difference in other clinical indicators.Practical ImplicationsFSD technology is low cost and easy to operate and has several applications. Compared with conventional complete denture restoration technology, FSDs can save time and have a comparable clinical effect.This clinical trial was registered at the Chinese Clinical Trial Registry. The registration number is ChiCTR1900021722.     

Stainless steel crowns as a restoration for permanent posterior teeth in people with special needs: A retrospective study

BackgroundLimited information exists regarding the use of stainless steel crowns (SSCs) in permanent teeth. The objective of this retrospective cohort study was to present the long-term clinical outcomes of the SSC compared with those of amalgam and composite resin restorations and the SSC radiographic outcomes in a special-needs population.MethodsThis study included 271 patients with at least 1 SSC restoration from the Mount Sinai Hospital Dentistry Clinic for Persons with Special Needs in Toronto, Ontario, Canada. A total of 2,621 posterior permanent tooth restorations were documented: 766 SSCs, 1,651 amalgam restorations, and 204 composite resin restorations. Clinical analysis included patient demographics, treatment parameters, and outcome assessments for each restoration recorded. Radiographic analysis of SSC restorations included 127 bite-wing radiographs and 118 periapical radiographs, measurement of interproximal bone loss, and assessment of periapical status using the Periapical Index Scale.ResultsThe 10-year survival rates for new SSC and amalgam restorations were 79.2% and 63.5%, respectively. The 91 SSC failures included 2 recementations, 33 replacements, and 56 extractions. Primary diagnoses at the time of failure included chronic periodontal disease (25) and loose or lost SSCs (24). Of the 528 failed conventional restorations that were replaced, 60% were replaced with SSCs. The mean alveolar bone loss from mesial and distal sites was 1.36 millimeters and 1.40 mm, respectively. Therefore, 93% of the sites recorded were less than 2 mm and classified as healthy. All pre-SCC and post-SSC periapical radiographs had healthy Periapical Index Scale scores (1 or 2) recorded over an average duration of 8.4 years (1-29.1 years).ConclusionsSSCs are a durable treatment option for the restoration of the posterior permanent dentition.Practical ImplicationsPosterior permanent teeth restored with stainless steel crowns can be expected to last for 10 years and represent a viable treatment choice for severely carious or fractured posterior permanent teeth.     

Effectiveness of barrier devices,high-volume evacuators,and extraoral suction devices on reducing dental aerosols for the dental operator: A pilot study

BackgroundThe COVID-19 pandemic has increased the importance of minimizing exposure to aerosols generated during dental procedures. The authors’ objective was to measure the aerosolized particles in the breathing zone of operators using several facial protection and filtration methods.MethodsTwenty-one dentists performed maxillary anterior incisor veneer preparations using a microscope and drape and loupes with or without a face shield. In each test condition, the following 3 levels of filtration were tested: no filtration, a high-volume evacuator [HVE], and an HVE with an extraoral suction device. Measurements were made using a mass monitor attached to the operator’s chest with inlet within 10 inches of the operator’s face.ResultsThe authors found that the microscope and drape provided the lowest levels of aerosolized particles compared with loupes with or without a face shield (P < .001). There was no detectable difference in the concentration of particles between operators wearing a face shield and wearing loupes alone (P = .47). The particles in each test condition were lowered when an HVE was used (P < .001) and further lowered with an extraoral suction device.ConclusionsThe findings of this study suggest that the use of a surgical microscope and bag barrier drape, HVE, and extraoral suction device result in the lowest concentration of aerosolized particles. The face shield did not appear to offer any protection from aerosolized particles. HVE and extraoral suction were effective in decreasing aerosols regardless of the type of facial protection used.Practical ImplicationsDentists can reduce exposure to aerosols with a drape, HVE, and extraoral suction.     

A Ser252Trp substitution in mouse FGFR2 results in hyperplasia of embryonic salivary gland parenchyma

ObjectivesMutations in the fibroblast growth factor receptor 2 (FGFR2) gene are responsible for several severe forms of craniosynostotic disorders, such as Apert and Crouzon syndromes. Patients with craniosynostotic disorders caused by a mutation in Fgfr2 present with several clinical symptoms, including hypersalivation. Here we used a transgenic mouse model of Apert syndrome (Fgfr2^+/S252W mice) to evaluate the morphology of the submandibular glands at embryonic day 15.5 (E15.5), the time point reported to mark the start of lumen formation.MethodsFgfr2^+/S252W mice were generated by crossing ACTB-Cre^+/+ and Fgfr2^+/Neo-S252W mice. After measuring body weight, the submandibular glands were collected at E15.5. H&E staining, immunostaining, and RT-qPCR were performed to investigate the development of the submandibular gland.ResultsThe number of ducts and acini in Fgfr2^+/S252W mice was significantly higher than in control littermates; however, lumen formation was not affected. The mRNA expression of Fgf1, Fgfr1, Mmp2, Bmp4, Bmp7, Dusp6, and Etv5 in Fgfr2^+/S252W mice was significantly higher compared to control littermates. Immunoreactivity for FGF3, FGF1, BMP4, and F4/80 was detected in the parenchyma of Fgfr2^+/S252W mice. The area of apoptotic cells stained with TUNEL in Fgfr2^+/S252W mice was significantly larger than that of the control littermates.ConclusionsThese results suggested that increased FGFR1 signaling and apoptosis in the submandibular glands of Fgfr2^+/S252W mice occurred at E15.5, leading to parenchymal hyperplasia. This study demonstrated that a Ser252Trp substitution in mouse FGFR2 resulted in hyperplasia of the submandibular gland parenchyma during development.     

Adipose-derived mesenchymal stem cells promote salivary duct regeneration via a paracrine effect

ObjectivesThe self-regeneration of exocrine tissues, including salivary glands, is limited and their regeneration mechanism has not yet been fully elucidated. Here we identify the role of adipose-derived mesenchymal stem cells (AMSCs) in salivary gland regeneration.MethodsAMSCs expressing mesenchymal stem cell markers were applied to a submandibular gland injury model and the mechanism of salivary gland repair and regeneration was analyzed.ResultsTransplanted green fluorescent protein (GFP)-labeled AMSCs grew tightly together and promoted ductal regeneration in the regenerative nodule, with slight infiltration of nonspecific immune cells. A comprehensive gene analysis through RNA-sequencing revealed increased expression of bone morphogenetic protein (BMP), transforming growth factor (TGF), and Wnt in AMSC-transplanted regenerative nodules. The factors released from AMSCs scavenge hydrogen peroxidase-induced reactive oxygen species (ROS) through Wnt promoter activity in vitro. Furthermore, AMSC-conditioned medium recovered the growth of the hydrogen peroxidase-damaged primordium of the submandibular gland culture ex vivo.ConclusionsThese results suggest that AMSC-released factors scavenge ROS and maintain salivary gland repair and regeneration via paracrine effects. Thus, AMSCs could be a practical and applicable tool for use in salivary gland regeneration.     

Adipokines in dental pulp: Physiological,pathological, and potential therapeutic roles

BackgroundHundreds of adipokines have been identified, and their extensive range of endocrine functions—regulating distant organs such as oral tissues—and local autocrine/paracrine roles have been studied. In dentistry, however, adipokines are poorly known proteins in the dental pulp; few of them have been studied despite their large number. This study reviews recent advances in the investigation of dental-pulp adipokines, with an emphasis on their roles in inflammatory processes and their potential therapeutic applications.HighlightsThe most recently identified adipokines in dental pulp include leptin, adiponectin, resistin, ghrelin, oncostatin, chemerin, and visfatin. They have numerous physiological and pathological functions in the pulp tissue: they are closely related to pulp inflammatory mechanisms and actively participate in cell differentiation, mineralization, angiogenesis, and immune-system modulation.ConclusionAdipokines have potential clinical applications in regenerative endodontics and as biomarkers or targets for the pharmacological management of inflammatory and degenerative processes in dental pulp. A promising direction for the development of new therapies may be the use of agonists/antagonists to modulate the expression of the most studied adipokines.     

Tooth loss in patients with and without diabetes: A large-scale,cross-sectional study of Mexican adults

BackgroundThe objective of this study was to compare the experience and distribution of tooth loss in people with and without diabetes.MethodsThe authors conducted a comparative cross-sectional study of patients at a public university. Analysis included medical records of those treated from 2013 through 2017. The dependent and main independent variables were the number of missing teeth and a diagnosis of diabetes, respectively. As covariables, the authors analyzed the sociodemographic and socioeconomic characteristics, as well as the general and oral health status of patients. A multivariate model based on negative binomial regression was constructed.ResultsOf the 3,406 medical records analyzed, 64.2% (n = 2,185) pertained to women, the mean age was 42.45 years, 87.9% did not have diabetes, and 12.1% had received a diagnosis of diabetes. The mean (standard deviation) number of missing teeth was 7.46 (7.89), 7.09 (7.60) in patients without diabetes, and 10.12 (9.32) in patients with diabetes. According to our final multivariate model, the expected mean number of missing teeth was 11.4% higher in patients with diabetes than in those without (P = .006). For every 1-year increase in age, the expected mean number of missing teeth increased by 3.9% (P < .001). Other variables related to tooth loss included occupation, marital status, and type of insurance.ConclusionsThe results of the study indicate that the mean number of missing teeth is higher in people with diabetes and suggest that certain socioeconomic inequalities exist in the area of oral health.Practical ImplicationsThe population needs to be apprised of the impact of diabetes on oral health.     

Association between metabolic syndrome and tooth loss: A systematic review and meta-analysis

BackgroundThe authors conducted a systematic review and meta-analysis to verify the existence and level of scientific evidence concerning the association between metabolic syndrome (MetS), as the main exposure, and tooth loss (TL), as the outcome.Types of Studies ReviewedThrough electronic databases and partially through gray literature, the authors identified observational studies in adults. The authors used no date or language restrictions. The authors evaluated the studies’ methodological quality by using the Newcastle-Ottawa Scale. The authors conducted a random-effects model meta-analysis. The authors assessed the quality of evidence by using the Grading of Recommendations Assessment, Development and Evaluation criteria.ResultsTwelve studies met the eligibility criteria, and 9 were retained for the meta-analysis. Most were cross-sectional studies with good methodological quality. Participants with MetS had fewer teeth (standardized mean difference, −2.77; 95% confidence interval, −4.56 to −0.98) and an increased likelihood of lacking functional dentition (odds ratio, 2.37; 95% confidence interval, 1.89 to 2.96) than did those without MetS. The overall quality of evidence was very low.Conclusions and Practical ImplicationsBetter-conducted longitudinal studies are necessary to establish a causal relationship between MetS and TL to inform the best strategies to prevent TL in populations with MetS.     

Impact of motivational interviewing on early childhood caries: A systematic review and meta-analysis

BackgroundThe authors aimed to assess the scientific evidence on motivational interviewing for the clinical reduction of early childhood caries compared with traditional dental health education.MethodsSearch terms were selected on the basis of Medical Subject Headings and non–Medical Subject Headings terms. The main key words were motivational interviewing, early childhood caries, and education. Potentially eligible studies involved the clinical assessment of caries rate in children whose parents or caregivers received motivational interviewing as an intervention. The authors assessed the risk of bias using the Cochrane risk-of-bias tool. In March 2019, the authors performed an electronic database search of literature published in English within the following databases: Scopus, Cochrane, PubMed, and Embase.ResultsOf 329 articles retrieved initially, 14 were eligible for inclusion in the systematic review and 3 articles contributed to the meta-analysis. For statistical analysis, the mean difference of continuous data was analyzed at a 95% confidence interval using the random-effects model.ConclusionsOverall, the evidence presented in this review was limited. Although the results of the meta-analysis showed that motivational interviewing is as effective as dental health education in controlling early childhood caries, we need more and better designed and reported interventions to assess its impact on early childhood caries accurately.     

Association of MMP9, MMP13 and MMP20 genes polymorphism with dental caries: A meta-analysis

ObjectivesGenetic factors can be involved in dental caries as the most common chronic oral diseases. The association between polymorphism of MMP9, MMP13 and MMP20 genes with tooth decay has been studied but contradictory outcomes have been indicated. Thus, a meta-analysis was done to get comprehensive outcomes in this path.Materials and methodsAll articles in English by March 2022 were searched with correlated keywords from known database as PubMed, Scopus, Embase and Web of Science, and the articles were selected in several stages based on exclusion and inclusion criteria. Comprehensive meta-analysis software v.2.0 was used for Meta-analysis.ResultsFinally, 11 related articles were selected for meta-analysis. According to the results, MMP9 and MMP20 polymorphisms were not related with increased susceptibility to caries in the studied models, but in the case of MMP13, a significant association was observed between gene polymorphism and caries risk.ConclusionThe results about MMP13 gene polymorphism showed that guanine G allele and GG genotype have a protective role and decrease the risk of dental caries. It should be noted that, these conclusions could be promoted by studies contain large sample sizes. Finding the genetic factors influencing tooth decay can help increase our current knowledge of caries pathology, predict its occurrence, and target genes at the molecular level to prevent it.     

Buccal bifurcation cyst: A case series and review of the literature

IntroductionBuccal bifurcation cyst is an inflammatory odontogenic cyst and constitutes up to 5% of all odontogenic cysts. The aim of this study was to report a series of cases, review the recent literature, and facilitate recognition and proper treatment of this entity.MethodsWith institutional review board approval, the authors retrieved all archival cases of buccal bifurcation cyst from the oral pathology biopsy service from 1994 through 2018. Patient age and sex, cyst location, clinician’s impression, radiographic appearance, diagnosis, and treatment data were recorded.ResultsA total of 10 cases were identified. Average patient age was 9 years. A slight male predilection was observed (n = 6, 60%). One hundred percent of cases were in the mandible, including 3 (30%) bilateral cases.ConclusionsMandibular buccal bifurcation cyst is an important entity in pediatric patients but may be less likely to be recognized by clinicians not regularly treating children. The results of this study are mostly consistent with the literature. Treatment is typically via enucleation or even more conservative modalities, and extraction should be avoided if possible.Practical ImplicationsBuccal bifurcation cysts should be treated via enucleation or even more conservative methods. If possible, the affected teeth should be preserved.