The burden of root caries: Updated perspectives and advances on management strategies

Novel Resin-Based Antibacterial Root Surface Coating Material to Combat Dental Caries

Root caries caused by cariogenic bacteria are a burden on a large number of individuals worldwide, especially the elderly. Applying a protective coating to exposed root surfaces has the potential to inhibit the development of caries, thus preserving natural teeth. This study aimed to develop a novel antibacterial coating to combat root caries and evaluate its effectiveness using the antibacterial monomer dimethylaminohexadecyl methacrylate (DMAHDM). DMAHDM was synthesized and incorporated into a resin consisting of 55.8% urethane dimethacrylate (UDMA) and 44.2% TEG-DVBE (UV) at a 10% mass fraction of glass filler. Multiple concentrations of DMAHDM were tested for their impact on the resin's mechanical and physical properties. S. mutans biofilms grown on resin disks were analyzed for antibacterial efficacy. Cytotoxicity was assessed against human gingival fibroblasts (HGFs). The results showed an 8-log reduction in colony-forming units (CFUs) against S. mutans biofilm (mean ± sd; n = 6) (p < 0.05) when 5% DMAHDM was incorporated into the UV resin. There was a 90% reduction in metabolic activity and lactic acid production. A low level of cytotoxicity against HGF was observed without compromising the physical and mechanical properties of the resin. This coating material demonstrated promising physical properties, potent antibacterial effects, and low toxicity, suggesting its potential to protect exposed roots from caries in various dental procedures and among elderly individuals with gingival recession.

CPP-ACP paste's effect on salivary conditions in patients with removable dentures

PURPOSE

Older adults with removable dentures experience high rates of both caries (when the natural dentition remains) and salivary gland dysfunction. While many commercial dental therapeutic agents target these two interrelated problems, none have been labeled for use on the fitting surface of removable dentures. Off-label use of MI Paste (GC America, Alsip, IL), a dental therapeutic containing casein-phosphopeptide-amorphous-calcium-phosphate (CPP-ACP), was investigated following its application to the fitting surface of complete denture(s) with subsequent effects on salivary conditions measured.

MATERIALS AND METHODS

Salivary flow rate and pH were recorded at baseline and 15 min following the application of 1 mL of CPP-ACP paste to the fitting surface of each participant's denture through whole saliva collection. To assess buffering capacity, equivalent volumes of 0.01 M lactic acid were added to the collected saliva samples, and pH reduction was measured. Comparisons of salivary parameters between baseline and post-CPP-ACP paste application and between subjects with and without self-reported xerostomia were conducted using a paired-sample t-test, Wilcoxon signed-rank test, or two-sample t-test as appropriate.

RESULTS

Of the 28 participants (mean age = 70.3 ± 13.7 years, 17 males), 11 reported xerostomia. CPP-ACP-paste application was associated with decreased pH reduction during acid challenge compared to baseline (0.95 ± 0.24 vs. 1.54 ± 0.53, p < 0.001), and a higher final pH following acid challenge (5.93 ± 0.34 vs. 5.40 ± 0.66, p < 0.001). While the flow rates observed at post-CPP-ACP paste application were greater than those at baseline, the difference was not statistically significant (0.67 ± 0.44 mL/min vs. 0.55 ± 0.34 mL/min, p = 0.053). No significant differences were found in any salivary parameters between participants with or without self-reports of xerostomia.

CONCLUSIONS

The findings highlight potential positive effects on salivary conditions following the application of the CPP-ACP-containing product, MI Paste, to the fitting surface of a removable complete denture as a potential caries-risk-management tool when natural dentition remains. Determining the caries-preventive clinical significance will require longer-term trials.

Depression and dental caries in US adults, NHANES 2015-2018

PURPOSE

This study aimed to investigate the link between depression and untreated dental caries among adults in the United States.

METHODS

Data were collected from the National Health and Nutrition Survey (2015-2018); respondents aged 20 years or older who completed a patient health questionnaire and underwent a comprehensive oral examination were included. Participants were categorized into three groups according to depressive symptoms as follows: those with no, mild, or moderate to severe depression. Data were weighted, and multiple potential covariates were included in the analysis to provide national estimates and account for the complex sample design. A multivariable weighted logistic regression model was performed to test the hypothesis that varying degrees of depression in American adults are associated with untreated dental caries. Subgroup analyses were performed based on age and gender after adjusting for potential covariates. A P value of <.05 was considered significant.

RESULTS

Among 8740 participants, the prevalence of untreated coronal and root caries was 20.50% and 12.92%, respectively. Moderate to severe depression was a significant risk factor (odds ratio, 1.25; 95% confidence interval, 1.09-1.66) for untreated root caries. The risk of untreated root caries increased by 87% in young adults (aged 20-44 years) and by 46% in women with moderate to severe depression. The suest analysis revealed that the impact of moderate to severe depressive disorder on untreated root caries was non-significantly different between the age subgroup (p=0.09) and sex subgroup (p=0.51). However, depression was non-significantly associated with untreated coronal caries (mild depression: OR, 1.07; 95% CI, 0.85-1.34; moderate to severe depression 1.06; 95% CI, 0.83-1.36; respectively).

CONCLUSION

The results of this study suggested a significant association between moderate and severe depression and untreated root caries; however, the association with untreated coronal caries was non-significant. In the United States, moderate and severe depression in adults is associated with root caries.

A cost-effectiveness analysis of fluoride varnish application in preventing Root caries in elderly persons: a Markov simulation study

BACKGROUND

Root caries are prevalent issues that affect dental health, particularly among elderly individuals with exposed root surfaces. Fluoride therapy has shown effectiveness in preventing root caries, but limited studies have addressed its cost-effectiveness in elderly persons population. This study aimed to evaluate the cost-effectiveness of a fluoride treatment program for preventing root caries in elderly persons within the context of Chinese public healthcare.

METHODS

A Markov simulation model was adopted for the cost-effectiveness analysis in a hypothetical scenario from a healthcare system perspective. A 60-year-old subject with 23 teeth was simulated for 20 years. A 5% sodium fluoride varnish treatment was compared with no preventive intervention in terms of effectiveness and cost. Tooth years free of root caries were set as the effect. Transition probabilities were estimated from the data of a community-based cohort and published studies, and costs were based on documents published by the government. The incremental cost-effectiveness ratio (ICER) was calculated to evaluate cost-effectiveness. Univariate and probabilistic sensitivity analyses were performed to evaluate the influence of data uncertainty.

RESULTS

Fluoride treatment was more effective (with a difference of 10.20 root caries-free tooth years) but also more costly (with a difference of ¥1636.22). The ICER was ¥160.35 per root caries-free tooth year gained. One-way sensitivity analysis showed that the risk ratio of root caries in the fluoride treatment group influenced the result most. In the probabilistic sensitivity analysis, fluoride treatment was cost-effective in 70.5% of the simulated cases.

CONCLUSIONS

Regular 5% sodium fluoride varnish application was cost-effective for preventing root caries in the elderly persons in most scenarios with the consideration of data uncertainty, but to a limited extent. Improved public dental health awareness may reduce the incremental cost and make the intervention more cost-effective. Overall, the study shed light on the economic viability and impact of such preventive interventions, providing a scientific basis for dental care policies and healthcare resource allocation.

Influence of surface pre-reacted glass-ionomer (S-PRG) filler eluate on collagen morphology, remineralization, and ultimate tensile strength of demineralized dentin

OBJECTIVE

To evaluate the effect of ions released from surface pre-reacted glass-ionomer (S-PRG) filler on collagen morphology, remineralization, and ultimate tensile strength (UTS) of demineralized dentin.

MATERIALS AND METHODS

Bovine incisor root dentins were demineralized with EDTA and divided into three treatment groups: 1) water (control); 2) S-PRG filler eluate; 3) 125 ppm sodium fluoride (NaF). After a 3-min treatment, the specimens were stored in simulated body fluid (SBF) for 3 months. Collagen morphology and remineralization were assessed using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FTIR). Additionally, ultimate tensile strength (UTS) was measured.

RESULTS

TEM and SEM demonstrated that S-PRG induced more effective remineralization compared to NaF, while the control group exhibited faint mineral deposition with collagen degradation. S-PRG displayed the most homogenous mineral deposition in collagen fibrils, along with closure of interfibrillar spaces. Extensive mineral precipitation was observed within dentinal tubules in the S-PRG group. In addition, S-PRG filler eluate demonstrated significantly higher phosphate-to-amide ratio and UTS compared to NaF and control groups (p < 0.05).

CONCLUSIONS

Ion released from S-PRG filler positively influenced collagen morphology, remineralization, and ultimate tensile strength of demineralized dentin.

CLINICAL SIGNIFICANCE

S-PRG filler enhances remineralization and improve the biomechanics of demineralized dentin.

The associations between dental disease and systemic health

Understanding the relationship between a patient's systemic and oral health is key for clinicians. The aim of this study was to determine if there is an association between specific findings in a dental exam, such as class V carious lesions, and the American Society of Anesthesiologists (ASA) classification as a proxy for systemic health. A retrospective chart review was performed on all patient charts that met inclusion criteria including detailed, complete, and vetted charts obtained over a three-year period in the predoctoral clinic of a United States dental college. Findings recorded at the initial exam included the decayed, missing or filled teeth (DMFT) score, the location of carious lesions and restorations, the presence of periodontal disease, the number of endodontically treated teeth and the number of fractured teeth or restorations. We found no association found between DMFT score and ASA status but did find that ASA I patients had a higher degree of occlusal carious lesions and that ASA III patients were more likely to have interproximal restorations and fractured teeth. We found associations between a greater number of missing teeth and the presence of periodontal disease with worsening ASA status. Our data suggest that ASA classification cannot be used as a reliable predictor for the health of a patient's dentition or the number of cervical caries. However, the data does demonstrate a positive correlation between the number of missing teeth and ASA status, promoting the idea that the number of missing teeth is a crude prognosticator of systemic health. This information can be used by physicians and dentists to help understand the relationships between a patient's dental and systemic health.

Oral health-related quality of life and depressive symptoms in adults: longitudinal associations of the English Longitudinal Study of Ageing (ELSA)

BACKGROUND

Little is known about the relationship between oral health status and depressive symptoms in adults in England. The aim of this study was to examine the longitudinal association between oral health parameters and depressive symptoms in adults in England.

METHODS

Data were obtained from the English Longitudinal Study of Aging (ELSA), which included information on self-rated oral health, oral impairment in daily life (Oral Impacts on Daily Performances, OIDP), and depressive symptoms (Center for Epidemiologic Studies Depression Scale, CES-D) in 6790 adults aged ≥ 50 years. Wave 3 data were used as baseline, while Waves 5 and 7 were used for follow-up assessments. Logistic regression was used to determine whether depressive symptoms at baseline anticipated self-rated oral health and OIDP and whether oral health status (at baseline) was associated with the development of depressive symptoms at follow-up assessment.

RESULTS

Participants with poor self-rated oral health were at higher risk of developing depressive symptoms, even after adjusting for behavioral, clinical, and sociodemographic characteristics (OR = 1.69, 95% CI 1.38-2.07). Similarly, having oral impacts on daily performances were associated with the development of depressive symptoms: The OR for developing depressive symptoms at Wave 5 or 7 was 2.19 (95% CI 1.62-2.96) after adjustment for all covariates. Participants with depressive symptoms at baseline were more likely to report poor self-rated oral health (OR = 1.93, 95% CI 1.52-2.44) or one or more oral impacts (OR = 1.86, 95% CI 1.45-2.40) at follow-up than those without depressive symptoms at baseline, even after adjusting for confounders.

CONCLUSIONS

In the present study, a bidirectional association was found between depressive symptoms and poor oral health in older adults. Maintaining good oral health in older adults may be a protective factor against depressive symptoms. Therefore, more attention should be paid to promoting oral health awareness in older adults, including encouraging regular dental checkups, proper toothbrushing and flossing techniques, and healthy lifestyles.

Prevalence of root caries in Indian population - a systematic review and meta-analysis

AIM

To evaluate the pooled prevalence of root caries among Indian population through systematic review and meta-analysis.

MATERIALS AND METHODS

The study protocol adhered to the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines and was registered in PROSPERO (CRD42022367365). Research articles published in English language till July 2022 were evaluated with the use of databases like PubMed, Science Direct, Google Scholar, Cochrane, and Scopus and employed standard Boolean operators.

RESULTS

The search turned up a total of 194 articles; however, only 14 of those matched the requirements for inclusion and were used to compile the meta-analysis. MedCalc® Statistical Software version 20.2 was used to determine the pooled estimates. Using the random effect model, the analysis was carried out. By estimating the heterogeneity using Higgins' I2 statistics, the extent and importance of differences between the chosen studies were ascertained. Publication bias was assessed using the funnel plot and Egger's test. The random effects model yielded a pooled prevalence of 27.617 (95% CI = 17.422-39.154).

CONCLUSION

Three out of ten persons in India may be affected by root caries, which is a serious health issue. To enhance the quality of life for the aged population, oral health policies and preventive actions should concentrate on this issue.

Association of Interdental Cleaning and Untreated Root Caries in Adults in the United States of America

PURPOSE

This study aimed to evaluate the association between interdental cleaning and untreated root caries amongst middle-aged and older adults in the US.

MATERIALS AND METHODS

Data were obtained from the National Health and Nutrition Examination Survey (NHANES) (2015-2016 and 2017-2018). Adults aged ≥40 years who underwent full mouth examination and root caries assessment were included. Participants were classified based on their interdental cleaning frequency as none, 1-3 d/wk, and 4-7 d/wk. Associations between interdental cleaning and untreated root caries were assessed using a weighted multivariable logistic regression model adjusted for sociodemographics, general behaviour, general health condition, oral conditions, oral health behavior, and dietary factors. Subgroup analyses stratified by age and sex were performed after adjusting for covariates in the logistic regression models.

RESULTS

The prevalence of untreated root caries was 15.3% amongst 6217 participants. Interdental cleaning for 4-7 d/wk was a significant risk factor (odds ratio, 0.67; 95% confidence interval, 0.52-0.85). It was associated with a 40% reduction in the risk of untreated root caries in participants aged 40 to 64 years and a 37% reduction in women. Untreated root caries was also significantly associated with age, family income, smoking status, root restoration, number of teeth, untreated coronal caries, and recent dental visit.

CONCLUSIONS

Interdental cleaning for 4-7 d/wk was associated with fewer untreated root caries amongst middle-aged adults and women in the US. The risk of root caries increases with age. Low family income was a risk indicator for root caries amongst middle-aged adults. Additionally, smoking, root restoration, number of teeth, untreated coronal caries, and recent dental visits were common risk factors for root caries in middle-aged and older people in the US.

Is there an association between periodontal disease and root caries? A systematic review and meta-analysis

Some periodontal diseases can be associated with cariogenic bacterial growth due to various oral health imbalances. This fact may be linked to a greater development of root caries. Thus, this systematic review analyzed the evidence on the association between periodontal disease and root caries. An electronic search was performed in five databases (Cochrane Library, LILACS, MedLine via PubMed, Scopus, and Web of Science) and two additional sources (Google Scholar and Open Grey) to partially capture the grey literature. The PECO strategy was used to identify prospective or retrospective observational studies assessing root caries in patients with periodontal disease without language or year publication restrictions. Two reviewers extracted data and evaluated the individual risk of bias in the eligible studies. Random effects meta-analyses were performed to calculate the Odds Ratio (OR). The risk of bias was assessed by the NIH tool, and the certainty of evidence was classified according to the GRADE tool. There were 1,725 studies retrieved, of which four met the eligibility criteria. All of them were evaluated for the control statements for possible confounders, bias consideration, and confounding factors because they had multivariate analysis. Adults with periodontal disease had a greater chance of presenting root caries than adults without, with OR 1.38 [CI 1.25, 1.53]. The certainty of evidence was classified as very low. Within the limits presented in this review, there was an association between periodontal disease and root caries, highlighted in the qualitative synthesis and the meta-analysis results.

The Role of Bacterial, Dentinal, Salivary, and Neutrophil Degradative Activity in Caries Pathogenesis

Until recently, it was widely accepted that bacteria participate in caries pathogenesis mainly through carbohydrate fermentation and acid production, which promote the dissolution of tooth components. Neutrophils, on the other hand, were considered white blood cells with no role in caries pathogenesis. Nevertheless, current literature suggests that both bacteria and neutrophils, among other factors, possess direct degradative activity towards both dentinal collagen type-1 and/or methacrylate resin-based restoratives and adhesives, the most common dental restoratives. Neutrophils are abundant leukocytes in the gingival sulcus, where they can readily reach adjacent tooth roots or gingival and cervical restorations and execute their degradative activity. In this review, we present the latest literature evidence for bacterial, dentinal, salivary, and neutrophil degradative action that may induce primary caries, secondary caries, and restoration failure.

Interactive Effect of Salivary Protein Carbonyl, Total Glutathione, pH, and Flow Rate on Root Caries Severity: A Case-Control Study

Aims and Objectives

Oxidant and antioxidant components in saliva play an essential role in caries development. The purpose of the current study was to disclose the interactive effect of salivary protein carbonyl (PC), total glutathione (GSH), pH, and flow rate on root caries severity.

Materials and Methods

The control and study groups consisted of 90 older adults of both genders classified into six groups: normal salivary flow rate with no root caries (control), normal salivary flow rate with incipient root caries, normal salivary flow rate with shallow root caries, hyposalivation with no root caries, hyposalivation with incipient root caries, and hyposalivation with shallow root caries. Each group consisted of 15 older adults. The study participants were selected from those patients who attended the teaching hospital at the College of the Dentistry/University of Baghdad and fit the study's criteria. Unstimulated saliva was collected. Both salivary pH and flow rate were determined immediately. After that, saliva was subjected to biochemical analysis to determine PC and total GSH levels colorimetrically. Root surface caries was diagnosed clinically using the Root Caries Index. Data were statistically analyzed using descriptive statistics, two-way univariate analysis of variance, two-way multivariate analysis of variance, and Pearson's correlation coefficient (α = 5%).

Results

Salivary total glutathione revealed a significant interactive effect with salivary flow rate and root decay severity. Levels of salivary total GSH were significantly higher in subjects with shallow root caries than those with incipient root caries; no root caries levels of salivary PC were significantly high in the hyposalivation group, but no correlation with caries severity was found. High root caries severity was found to be associated with reduced salivary pH and flow rate.

Conclusion

A significant interactive effect was recorded for salivary flow rate, pH, and total GSH on root caries severity except for salivary PC.

Effect of Silver Diamine Fluoride on Bacterial Biofilms-A Review including In Vitro and In Vivo Studies

Caries/carious lesions are a growing concern among the general population across the world, and different strategies are evolving to combat the bacterial invasion that resultantly leads to caries. In this systematic review, we are looking to analyse the role of silver diamine fluoride (SDF) on the growth of bacterial biofilms. The search strategy for the studies to be selected for the review was initiated by a search across multiple databases, which ultimately yielded 15 studies that were in accordance with our objectives. The reviewed articles indicate a very clear correlation between the usage of SDF and the decrease in bacterial biofilms, which are limited not just to one or two but multiple bacterial species. As shown by the events favoring SDF's odds ratio of 3.59 (with a 95% confidence interval of 2.13 to 6.05), a risk ratio of 1.63 (1.32 to 2.00), and a risk difference of 0.28 (0.16 to 0.40), there was strong evidence that SDF is a successful treatment for reducing bacterial biofilms in dental practice. This study offers substantial proof that SDF works well to reduce bacterial biofilms in dentistry practices. We advise further investigation to examine the potential of SDF as a standard therapy choice for dental caries and related conditions given the obvious relationship between the use of SDF and the reduction in bacterial biofilms.

Inorganic Compounds as Remineralizing Fillers in Dental Restorative Materials: Narrative Review

Secondary caries is one of the leading causes of resin-based dental restoration failure. It is initiated at the interface of an existing restoration and the restored tooth surface. It is mainly caused by an imbalance between two processes of mineral loss (demineralization) and mineral gain (remineralization). A plethora of evidence has explored incorporating several bioactive compounds into resin-based materials to prevent bacterial biofilm attachment and the onset of the disease. In this review, the most recent advances in the design of remineralizing compounds and their functionalization to different resin-based materials' formulations were overviewed. Inorganic compounds, such as nano-sized amorphous calcium phosphate (NACP), calcium fluoride (CaF₂), bioactive glass (BAG), hydroxyapatite (HA), fluorapatite (FA), and boron nitride (BN), displayed promising results concerning remineralization, and direct and indirect impact on biofilm growth. The effects of these compounds varied based on these compounds' structure, the incorporated amount or percentage, and the intended clinical application. The remineralizing effects were presented as direct effects, such as an increase in the mineral content of the dental tissue, or indirect effects, such as an increase in the pH around the material. In some of the reported investigations, inorganic remineralizing compounds were combined with other bioactive agents, such as quaternary ammonium compounds (QACs), to maximize the remineralization outcomes and the antibacterial action against the cariogenic biofilms. The reviewed literature was mainly based on laboratory studies, highlighting the need to shift more toward testing the performance of these remineralizing compounds in clinical settings.

In situ detection of endogenous proteolytic activity and the effect of inhibitors on tooth root surface

OBJECTIVES

The aim of this study was to clarify the distribution and activity of proteolytic enzymes and examine the inhibitory effects of various substances on this proteolytic activity on tooth root surfaces in situ.

METHODS

Disk-shaped bovine tooth root samples were partly pretreated in acid solution (50 mM lactic acid buffer, pH 4.0) for 48 h. The fluorescence intensity of samples was detected with fluorescent substrate solution for collagenase and gelatinase using a stereoscopic fluorescence microscope for 60 min. The acid-pretreated and non-acid-pretreated root samples were treated with chlorhexidine (CHX), sodium fluoride (NaF), epigallocatechin gallate (EGCG), and calcium hydroxide (Ca(OH)₂) for 10 min, and silver diamine fluoride (SDF) for 10, 30, and 60 s. These samples were immersed in the fluorescence substrate solution at pH 7.0, and the fluorescence intensity of samples was detected. The fluorescence intensity was calculated using analysis software.

RESULTS

Gelatinase activity was detected in root samples. Gelatinase activity of the acid-pretreated side was significantly higher than that of the non-acid-pretreated side (1.63 times) at 60 min. CHX, EGCG, Ca(OH)₂, and SDF decreased the gelatinase activity of root samples, while NaF had no effect.

CONCLUSIONS

Gelatinase activity was detected from the root in situ and it was increased by acid-pretreatment. CHX, EGCG, Ca(OH)₂, and SDF inhibited gelatinase activity.

CLINICAL SIGNIFICANCE

Substances that inhibit proteolytic activity found in this research method will be useful for root caries prevention.

Prevalence of Dental Caries in Patients on Renal Replacement Therapy-A Systematic Review

Patients under renal replacement therapy (RRT) often show oral problems, including dry mouth, periodontal and dental diseases. This systematic review aimed to evaluate the caries burden in patients on RRT. Therefore, a systematic literature search based on the databases PubMed, Web of Science and Scopus was performed by two independent individuals in August 2022. Search terms were: "caries" AND "dialysis", "caries" AND "renal replacement therapy", "caries" AND "kidney". The systematic process was complemented by manual search. Studies on adult patients (age ≥ 18 years), treated by any form of RRT and explicitly reporting caries prevalence or incidence were checked for their eligibility and subsequently analyzed qualitatively. For all included studies, a quality appraisal was applied. From the systematic search, 653 studies were identified, of which 33 clinical investigations were included in the qualitative analysis. The majority (31 studies) of all included patients underwent hemodialysis (HD), with a sample size between 28 and 512 participants. Eleven studies investigated a healthy control group. Oral examinations were heterogeneous across studies; the caries burden was primarily assessed by decayed-(D-T), missing- and filled-teeth index (DMF-T). The number of decayed teeth ranged between 0.7 and 3.87 across studies. Only six out of these 11 studies found significant differences in caries prevalence/incidence between RRT and controls, whereby only four studies confirmed worse caries burden in RRT individuals. No information was provided on caries stadium (initial caries, advanced caries, invasive treatment need), caries activity or location (e.g., root caries) across studies. Most of the included studies were assessed to be of moderate quality. In conclusion, patients on RRT suffer from a high prevalence of dental caries. Alongside a need for further research in the field, improved, multidisciplinary, patient-centered dental care concepts are required to support dental and overall oral health in individuals on RRT.

Dental innovations which will influence the oral health care of baby boomers

From the widespread use of smartphones and tablets to the multitude of applications available, older adults are showing an interest in utilizing technology to maintain their independence and to improve their quality of life. As technology continues to advance and be incorporated into many day-to-day activities, the baby boom generation will see these changes affecting the way they access and utilize dental services. Innovative toothbrushes and chemotherapeutics are continuing to be developed and utilized by many older adults. Within the dental office, older adults are seeing greater application of technology in every day dental procedures. These include the use of teledentistry, artificial intelligence (AI), innovative restorative materials, digitization of fixed and removable prosthodontics, cone beam computed tomography (CBCT) scans to guide dental implant placement and endodontic procedures. There is also new technology to aid in cancer detection and shielding during cancer treatment. Improved communication between the medical and dental fields has become increasingly necessary to facilitate effective patient care and a few innovative healthcare systems have begun to consolidate these services. Overall, the baby boom generation will continue to see dental innovations that will change the way they experience everyday life and dental services.

Effects of Acidic Challenge on Demineralized Root Surface Treated with Silver Diamine Fluoride and Potassium Iodide

BACKGROUND

The aim of the study was to assess the protective effect of applying potassium iodide (KI) over silver diamine fluoride (SDF) on demineralized root dentin in the case of a sustained acidogenic attack.

METHODS

Forty caries-free third molars were used in the study. A diamond disc was used to separate the roots and the tooth crowns from the roots. Each root fragment was randomly distributed in one of the four study groups: C-samples were not demineralized; DD-demineralized samples; RS1-demineralized samples covered with SDF+KI (RS-Riva Star product, SDI limited, Bayswater, Australia); RS2-demineralized samples covered with SDF+KI and submersed to another acidic challenge for 3 days. SEM and EDX were used for the morphological and elemental analysis. Vickers hardness assessment was performed using a tribometer CETR UMT-2 (Bruker Corporation, Berlin, Germany). One-way ANOVA and post hoc Bonferroni tests were used for the statistical analysis with a significance level of p < 0.05.

RESULTS

Morphological and elemental changes were observed on the surface of the study samples. Significant differences were observed between the recorded hardness values of groups C and DD (p = 0.005), C and RS2 (p = 0.002), DD and RS1 (p = 0.011); RS1 and RS2 (p = 0.004).

CONCLUSIONS

The application of SDF and KI (Riva Star product) on root dentin caries resulted in the formation of a heterogeneous outer layer that sealed the dentin and increased the microhardness of the treated surface. In the conditions of the present study, this layer did not provide enough protection for root dentin exposed to continuous attacks.

Development of Root Caries Prevention by Nano-Hydroxyapatite Coating and Improvement of Dentin Acid Resistance

There is no established method for optimizing the use of dentin to prevent root caries, which are increasing in the elderly population. This study aimed to develop a new approach for root caries prevention by focusing on bioapatite (BioHap), a new biomaterial, combined with fluoride. Bovine dentin was used as a sample, and an acid challenge was performed in three groups: no fluoride (control group), acidulated phosphate fluoride treatment (APF group), and BioHap + APF treatment (BioHap group). After applying the new compound, the acid resistance of dentin was compared with that of APF alone. The BioHap group had fewer defects and an increased surface hardness than the APF group. The BioHap group had the smallest lesion depth and least mineral loss among all groups. Using a scanning electron microscope in the BioHap group showed the closure of dentinal tubules and a coating on the surface. The BioHap group maintained a coating and had higher acid resistance than the APF group. The coating prevents acid penetration, and the small particle size of BioHap and its excellent reactivity with fluoride are thought to have contributed to the improvement of acid resistance in dentin. Topical fluoride application using BioHap protects against root caries.

Clinical and primary evidence of silver diamine fluoride on root caries management

Root caries is a growing problem for the worldwide aging population. Silver diamine fluoride (SDF) contains high concentrations of silver and fluoride ions, which prevents and arrests root caries, as well as dentin caries in the primary teeth of young children. Unlike other fluoride products that mainly reduce the formation of new carious lesions, 38% SDF is an effective agent that can efficiently arrest the carious process, remineralize the decayed dental tissues, and protect the tooth structure against the formation of new caries lesions. The use of SDF can result in more caries-resistant tooth structures. Despite these merits, its clinical disadvantages are the deep penetration of silver ions and sequential formation of silver compounds, which cause esthetic concern due to the discoloration and impaired efficacy of dentin bonding after using SDF. Thus, this narrative review, by addressing the primary experimental results and clinical applications of SDF on root caries, proposes management methods for root caries in conjunction with the application of SDF. We propose a two-visit treatment protocol to take advantage of the SDF application for root surface caries and utilize the discoloration caused by SDF.

Demonstration of an optical dentin hardness measuring device using bovine dentin with different demineralization times

SIGNIFICANCE

The increase in root caries is a serious problem as society ages. Root caries is diagnosed by inspection and palpation, which are qualitative. A method to objectively and quantitatively evaluate the progress of root caries in a clinical setting is strongly desired. The root caries could be diagnosed by measuring hardness because dentin becomes softer as the caries progresses. Vickers hardness has been customarily used as an indicator of tooth hardness. However, this method cannot be used to in vivo teeth because the teeth must be dried prior to measurement to make the indentation. A hardness meter using an indenter with light for tooth monitoring (HAMILTOM) is proposed as an optical device. HAMILTOM could measure hardness of teeth in wet condition as a dark area while applying a load to dentins without drying. Therefore, HAMILTOM may realize hardness measurements of in vivo teeth in a clinical setting quantitatively.

AIM

The aim of our study is to demonstrate the optical dentin hardness measuring device HAMILTOM using bovine dentin with different demineralization times and to evaluate the correlation between the dark areas measured by HAMILTOM and the Vickers hardness measured by the Vickers hardness tester.

APPROACH

The samples were 20 bovine dentins. They were demineralized by a lactic acid solution with different times and divided into groups 1 and 2 of 10 samples each. In both groups, the dark areas and Vickers hardness were measured for each sample. Group 1 was used to obtain a calibration curve to calculate Vickers hardness from the dark area. Group 2 was used to validate the calibration curve obtained from the dentin samples of group 1.

RESULTS

The areas appearing black without a total internal reflection of the indenter measured by HAMILTOM increased as the demineralization time increased. Additionally, the Vickers hardness of group 2 calculated by the dark areas of group 2 and the calibration curve obtained in group 1 and the Vickers hardness of group 2 measured by the Vickers hardness tester were strongly correlated with a determination coefficient of 0.99.

CONCLUSIONS

The results demonstrate that HAMILTOM may be a suitable alternative to the conventional method. Unlike the conventional method, which cannot be used for in vivo teeth, HAMILTOM holds potential to quantitatively evaluate the progress of caries in in vivo teeth.

Clinical and Microbiological Evaluation of a Chlorhexidine-Modified Glass Ionomer Cement (GIC-CHX) Restoration Placed Using the Atraumatic Restorative Treatment (ART) Technique

The aims of this study were to investigate the clinical effectiveness and patient acceptability of a modified glass ionomer cement placed using the atraumatic restorative treatment (ART) technique to treat root caries, and to carry out microbiological analysis of the restored sites. Two clinically visible root surface carious lesions per participant were restored using ART. One was restored with commercial glass ionomer cement (GIC) (ChemFil® Superior, DENTSPLY, Konstonz, Germany) which acted as the control. The other carious root lesion was restored with the same GIC modified with 5% chlorhexidine digluconate (GIC-CHX; test). Patient acceptability and restoration survival rate were evaluated at baseline and after 6 months. Plaque and saliva samples around the test and control restorations were collected, and microbiological analysis for selected bacterial and fungal viability were completed at baseline, and after 1, 3, and 6 months. In total, 52 restorations were placed using GIC and GIC-CHX in 26 participants; 1 patient was lost to follow-up. After reviewing the restorations during their baseline appointments, participants indicated that they were satisfied with the appearance of the restorations (n = 25, 96%) and did not feel anxious during the procedure (n = 24, 92%). Forty-eight percent (n = 12) of the GIC-CHX restorations were continuous with the existing anatomic form as opposed to six for the GIC restorations (24%), a difference which was statistically significant (p = 0.036). There was no statistically significant reduction in the mean count of the tested microorganisms in plaque samples for either type of restorations after 1, 3, or 6 months. Restoration of carious root surfaces with GIC-CHX resulted in higher survival rates than the control GIC. ART using GIC-CHX may therefore be a viable approach for use in outreach dental services to restore root surface carious lesions where dental services are not readily available, and for older people and special needs groups.

Multiple Chronic Diseases Associated With Tooth Loss Among the US Adult Population

Background

Half of US adults aged 20–64 years have lost at least one permanent tooth; one in six adults aged 65 and over in the USA is edentulous. Tooth loss and edentulism interfere with nutritional intake and quality of life. Although selected chronic diseases (e.g., diabetes) have been identified as possible risk factors for tooth loss, data on multiple chronic diseases and on having two or more concurrent chronic diseases (multimorbidity) in relation to tooth loss are lacking. Therefore, this study aimed to assess the association between multiple chronic diseases, multimorbidity, and tooth loss in US adults.

Methods

We performed a secondary data analysis using the US 2012 Behavioral Risk Factor Surveillance System (BRFSS), a national cross-sectional telephone survey studying health conditions and health behaviors among US adults (≥18 years) who are non-institutionalized residents. Variables were derived from the BRFSS Standard Core Questionnaire. Descriptive analysis including means, standard deviations (SDs), and percentages was calculated. Sample weights were applied. The stepwise multinomial logistic regression method was used to examine the relationship between several chronic diseases and tooth loss. Separate multinomial logistic regression models were used to examine the relationship between multimorbidity and tooth loss among all adults aged more than 18 years, adults aged 18–64 years, and adults aged more than 65 years, respectively.

Results

Among the samples (n = 471,107, mean age 55 years, 60% female), 55% reported losing no tooth loss, 30% reported losing one to five teeth, 10% reported losing six or more but not all teeth, and 5% reported losing all teeth. After adjusting for demographic characteristics, socioeconomic status, smoking, BMI, and dental care, chronic diseases that were associated with edentulism were chronic obstructive pulmonary disease (COPD) [adjusted risk ratio (adj. RR) 2.18, 95% confidence interval (CI) 2.08–2.29]; diabetes (adj. RR 1.49, 95% CI 1.44–1.56); arthritis (adj. RR 1.49, 95% CI 1.44–1.54); cardiovascular disease (adj. RR 1.38, 95% CI 1.30–1.45); stroke (adj. RR 1.31, 95% CI 1.24–1.40); kidney disease (adj. RR 1.16, 95% CI 1.08–1.25); cancer (adj. RR 1.05, 95% CI 1.01–1.11); and asthma (adj. RR 1.07, 95% CI 1.02–1.12). For those who reported losing six or more teeth, the association remained significant for all the chronic diseases mentioned, albeit the magnitude of association appeared to be comparative or smaller. In addition, adults with multimorbidity were more likely to have tooth loss (loss of one to five teeth: adj. RR 1.17, 95% CI 1.14–1.19; loss of six or more teeth: adj. RR 1.78, 95% CI 1.73–1.82; edentulous: adj. RR 2.03, 95% CI 1.96–2.10).

Conclusions

Multiple chronic diseases were associated with edentulism and tooth loss. People with multimorbidity are more likely to be edentulous than those with one or no chronic disease. The findings from this study will help to identify populations at increased risk for oral problems and nutritional deficits, thus the assessment of oral health should be evaluated further as an important component of chronic illness care.

How do carious root lesions develop after the end of professional preventive measures?—Preliminary findings of a randomized clinical trial

Aim of this randomized clinical trial was to assess the development of root caries lesions with and without (adjuvant) professional prevention treatment over 24 months. 20 participants with two or three non-cavitated root carious lesions were included (n = 52), whereby lesions were randomly assigned to one out of three groups depending on varnish application (CF: Cervitec F [n = 20], P: placebo [n = 20], DP: Duraphate [n = 12]). All lesions were assessed by quantitative light-induced fluorescence (QLF; QRayCam); following outcome parameters were analyzed: fluorescence loss (ΔF %), lesion volume (ΔQ %µm²) and bacterial activity (ΔR %). Professional tooth cleaning and adjuvant varnish application were performed at baseline, after 3, 6, and 9 months. A follow-up examination was performed 1 year after preventive care with varnish application 24 months after baseline. ∆F showed a significant time effect in CF (p = 0.03), which was not confirmed in post hoc analysis (p > 0.05). For P and DP, no time effect was detected (p > 0.05). ∆Q was significantly higher 12 months after baseline in CF (p = 0.02). In P, a significant time effect occurred (p = 0.01), without significant results in post hoc testing. ∆R showed higher values at baseline vs. 12 months in CF (p = 0.03) and 24 months compared to 12 months in DP (p = 0.02). Professional preventive treatment inhibited the progression of root caries lesions beyond their termination for 12 months, irrespective of an adjunctive varnish application. Preventive measures have a long-term effect on root carious lesions, even 1 year after their termination.

Effect of high-fluoride dentifrice on root dentine and bacterial composition in a multispecies biofilm model

The present study evaluated the effect of high-fluoride dentifrice on dentine demineralization and bacterial composition in a multispecies biofilm model in vitro. A seven-organism bacterial consortium was grown on bovine dentine discs in a high-throughput active attachment model. The biofilms were submitted twice per day to the following dentifrices treatments: 5,000 ppm F, 1,100 ppm F, with placebo as a negative control. After 5 days of biofilm growth, dentine samples were assessed by transversal microradiography, the biofilm was collected for bacterial counts and the pH of the media was determined. Lower integrated mineral loss values were observed when 5,000 ppm F-treatment was used compared to the other treatments. Overall microbiological counts decreased with increasing F-concentration as well the pH of the media throughout the experiment. The 5,000 ppm F-treatment caused a shift in microbial composition and reduced dentine demineralization in the in-vitro experimental model.

Anti-Demineralization Effects of Dental Adhesive-Composites on Enamel-Root Dentin Junction

Oral biofilm reactor (OBR) and pH cycling (pHC) artificial caries model were employed to evaluate the anti-demineralization effects of four composite filling systems on enamel-root dentin junction. Sixty-four enamel-root dentin blocks (6 mm × 6 mm × 2 mm) each with a cylindrical cavity were randomly assigned to the pHC and OBR group, then four subgroups (n = 8) and filled with either the Beautifil II (BEF, SPRG-filler-containing) or Estelite (EST) composite after the adhesive (either Single Bond Universal (SBU) or FL Bond II (FL, SPRG-filler-containing)). The demineralization lesions of filling interface were examined by micro-computerized tomography (μCT) and swept-source-optical coherence tomography (SS-OCT). According to the degree of interface damage, the caries lesions were sorted into four types: Type A and B (no attachment loss); Type C and D (attachment loss). EST/SBU showed the worst demineralization lesion and attachment loss (100% Type D), while BEF/FL exhibited the shallowest lesion depth (p < 0.05, 145 ± 45 μm on enamel, 275 ± 35 μm on root dentin) and no attachment loss (75% Type A and 25% Type B). Using FL adhesive alone does not effectively reduce enamel demineralization. BEF plays a leading role in acid resistance. The combination of BEF and FL showed a cumulative synergistic effect on anti-demineralization.

Bifunctional Composites for Biofilms Modulation on Cervical Restorations

Cervical composites treating root carious and noncarious cervical lesions usually extend subgingivally. The subgingival margins of composites present poor plaque control, enhanced biofilm accumulation, and cause gingival irritation. A potential material to restore such lesions should combine agents that interfere with bacterial biofilm development and respond to acidic conditions. Here, we explore the use of new bioresponsive bifunctional dental composites against mature microcosm biofilms derived from subgingival plaque samples. The designed formulations contain 2 bioactive agents: dimethylaminohexadecyl methacrylate (DMAHDM) at 3 to 5 wt.% and 20 wt.% nanosized amorphous calcium phosphate (NACP) in a base resin. Composites with no DMAHDM and NACP were used as controls. The newly formulated 5% DMAHDM-20% NACP composite was analyzed by micro-Raman spectroscopy and transmission electron microscopy. The wettability and surface-free energy were also assessed. The inhibitory effect on the in vitro biofilm growth and the 16S rRNA gene sequencing of survival bacterial colonies derived from the composites were analyzed. Whole-biofilm metabolic activity, polysaccharide production, and live/dead images of the biofilm grown over the composites complement the microbiological assays. Overall, the designed formulations had higher contact angles with water and lower surface-free energy compared to the commercial control. The DMAHDM-NACP composites significantly inhibited the growth of total microorganisms, Porphyromonas gingivalis, Prevotella intermedia/nigrescens, Aggregatibacter actinomycetemcomitans, and Fusobacterium nucleatum by 3 to 5-log (P < 0.001). For the colony isolates from control composites, the composition was typically dominated by the genera Veillonella, Fusobacterium, Streptococcus, Eikenella, and Leptotrichia, while Fusobacterium and Veillonella dominated the 5% DMAHDM-20% NACP composites. The DMAHDM-NACP composites contributed to over 80% of reduction in metabolic and polysaccharide activity. The suppression effect on plaque biofilms suggested that DMAHDM-NACP composites might be used as a bioactive material for cervical restorations. These results may propose an exciting path to prevent biofilm growth and improve dental composite restorations' life span.

Perspective and practice of root caries management: A multicountry study - Part II: A deeper dive into risk factors

BACKGROUND

The potential of an improved understanding to prevent and treat a complex oral condition such as root caries is important, given its correlation with multiple factors and the uncertainty surrounding the approach/material of choice. Deeper insights into risk factors may improve the quality of treatment and reduce the formation of root surface caries.

AIM

The present work aims to gain knowledge about dentists' opinions and experiences on assessing the risk factor related to the development of root caries and to help identify any overlooked factors that may contribute to less efficacious clinical outcomes.

METHODOLOGY

A questionnaire related to root surface caries was distributed among practicing dentists in nine different countries, namely the United Kingdom, Libya, Jordan, Saudi Arabia, Egypt, Brazil, India, Malaysia, and Iraq. Questionnaire responses were analyzed, and the results were compared among the groups.

RESULTS

Dentists around the world ranked the oral hygiene status of patients as the most important factor in the development of root surface caries. Patients with poor oral hygiene, active periodontal disease, reduced salivary flow, and gingival recession are perceived to have a higher risk of developing new root surface caries. There is a greater focus on prevention in the UK and greater levels of untreated dental disease in other countries, especially those recovering from civil wars.

CONCLUSION

This work identified some overlooked factors that may have contributed to the less efficacious clinical outcomes reported in the literature. It is hoped that this deep dive into risk factors coupled with the findings presented in Part I of this study will be used as a basis for a more comprehensive investigation into the management of patients with root surface caries.