Design of the Prevention of Adult Caries Study (PACS): a randomized clinical trial assessing the effect of a chlorhexidine dental coating for the prevention of adult caries

Clinical Trials with Herbal Products for the Prevention of Dental Caries and Their Quality: A Scoping Study

It is currently recognized that an injudicious strategy about caries in the last decades has been not only focusing of research mostly in children, but also the narrow focusing on fluoride, because despite sufficient availability of fluoride in water and oral healthcare products, caries levels escalate steadily as people get older and caries remain a main public health issue to be settled. In the last two decades the scientific community intensified efforts of exploring other products for caries prevention, herbal products being one of these approaches. Preliminary evidence indicated that clinical trials for caries prevention with herbal products are heterogeneous in design, quality and products evaluated, we therefore performed a scoping review intended to explore the main characteristics of such clinical trials. From an initial collection of 1986 unique papers from different literature databases, 56 articles satisfied the inclusion and exclusion criteria. The species investigated, dosage forms, study designs, duration of intervention, controls, endpoints, quality of reporting, and risk of bias are discussed. Of the trials reviewed here, 85.71% reported positive results but given the methodological flaws and biases affecting them, it is difficult to conclude on the efficacy of those products based on the studies published thus far.

Calibration of dentists for Caries Management by Risk Assessment Research in a Practice Based Research Network - CAMBRA PBRN

Background

To prove that Caries Management by Risk Assessment (CAMBRA) can be successfully implemented in dental practices outside of the university setting, dentists in the San Francisco Bay Area (CA) were approached to participate in a Practice Based Research Network (PBRN) study. The overall goal of the CAMBRA-PBRN study was to recruit 30 dentists to perform a two-year study involving approximately 900 patients. Goal of the calibration study was to standardize and calibrate dentists potentially participating in the CAMBRA-PBRN study.

Methods

To minimize inter-examiner variability in data collection, including classification of carious lesions and recording of existing restorations, participating dentists were trained and calibrated in accurate DMFS (decayed, missing, filled surfaces) charting. Dentists were also trained and calibrated to diagnose and differentiate between sound surfaces and non-cavitated caries lesions (International Caries Detection and Assessment - ICDAS scores 1 and 2) for posterior occlusal surfaces.

Thirty dentists were calibrated to a single gold standard examiner (BJ) during 6 calibration sessions, between 2011 and 2014. Kappa statistics were used to determine inter-examiner reliability on 13 or more patients, aged 12–63 (average age 38 ± 15 years), per examiner during each session, resulting in 94 patient encounters over the course of all 6 sessions. To participate in the main study, examiners needed to achieve a minimum required kappa of 0.75. During the calibration process, examiners scored between 1036 and 2220 tooth surfaces.

Results

The kappa values (unweighted kappa) of the participating dentists compared to the gold standard examiner ranged from 0.75 to 0.90, with an average kappa of 0.84 ± 0.03. 90% of the examiners achieved overall kappa values above 0.8. However, separate reliability for assessment of non-cavitated lesions, as in other studies, was lower (0.55 ± 0.15). Multiple subcategories were evaluated. All dentists reached sufficient reliability values to proceed into the study; nevertheless, one dentist discontinued with the study due to scheduling conflicts.

Conclusions

The high inter-examiner reliability results have shown that dentists who work in primarily non-research based practices can be effectively standardized and calibrated in data collection, based on specific guidelines created to anticipate potential research study scenarios.

Caries-risk profiles in Italian adults using computer caries assessment system and ICDAS

The aim of this study was to examine the correlation among socio-behavioral factors, caries status and caries risk, calculated through Cariogram, in an adult population. Four hundred eighty subjects (mean age 40.73, SE ± 0.33) randomly selected from the municipal electoral registry consented to participate in the survey. Subjects were examined, and the International Caries Detection Assessment System (ICDAS) index was registered. A highly structured questionnaire was submitted to investigate (1) personal data (i.e., age, gender, educational level, job categorization), (2) life-style behavior (i.e., smoking and dietary habits), and (3) oral health behavior (i.e., tooth brushing, use of fluoride and dental check-up frequency). An evaluation of the mutans streptococci concentration in saliva was also performed. Information on caries-related factors was entered into the Cariogram in order to generate an individual caries risk profile for each subject. Multinomial logistic regression was performed using Cariogram levels as the dependent variable. The possible correlated variables were analyzed using the principal component analysis (PCA). Considering ICDAS scores, 5.62% of the sample had at least an initial decay (ICDAS = 1-2), whereas 40.83% of the sample presented at least one moderate decay (ICDAS = 3-4) and 17.08% a severe decay (ICDAS = 5-6). Decay at ICDAS levels 5-6 and more than 5 missing teeth were statistically associated with Cariogram scores (OR = 2.36, 95%CI = 1.83-3.03 and OR = 1.43, 95%CI = 1.13-1.82, respectively). The results suggest that the Cariogram model was able to identify caries-related factors in an adult population. A direct association among the risk categories from Cariogram, the caries status and some socio-behavioral variables was verified.

Predictors of coronal caries progression in adults: results from the Prevention of Adult Caries Study

OBJECTIVES

This secondary analysis of data from the Prevention of Adult Caries Study (PACS) assesses risk factors for progression of coronal caries.

METHODS

Participants (n = 983) were adults at increased caries risk with at least one cavitated and one noncavitated lesions who were enrolled in a randomized clinical trial to test the effect of a 10% w/v chlorhexidine varnish coating on caries progression. Calibrated examiners scored tooth surfaces using a modified International Caries Detection and Assessment System (ICDAS) classification at baseline and at 7 and 13 months postrandomization. Potential baseline predictors of caries risk were used in adjusted negative binomial regression models to predict net D2FS increment and in linear regression models to predict the rank-normalized net D12FS increment.

RESULTS

Mean (SD) D2FS and D12FS increments were and 2.4 (3.1) and 2.1 (6.9), respectively. In multivariate analyses, two or more baseline D2 lesions, consumption of acidic drinks, and increasing age were all significantly associated with increased D2FS and D12FS risk. Daily flossing also was associated with increased D2FS risk. More frequent dental care at baseline was associated with significantly decreased caries risk for both increments.

CONCLUSIONS

The general concordance of risk factors in the D12FS and D2FS models lends support to the hypothesis that the D1 increment is an intermediate stage in the progression to fully cavitated lesions.

Targeted antimicrobial treatment to re-establish a healthy microbial flora for long-term protection

Streptococcus mutans has been implicated as the major acid-producing (cariogenic) bacterium. Dietary sugars and other factors may cause an imbalance of oral microflora that enables S. mutans to become dominant in the multi-species biofilms on the tooth surface, which could lead to dental caries. The application of broad-spectrum antimicrobials often results in re-colonization and re-dominance of S. mutans within oral flora, while in contrast, therapies capable of selective elimination of S. mutans from oral microbial communities may help to re-establish the normal flora and provide long-term protection. C16G2, a novel synthetic antimicrobial peptide with specificity for S. mutans, was found to have robust killing efficacy and selectivity for S. mutans in vitro. A subsequent pilot human study found that a single application of C16G2 in the oral cavity (formulated in a mouthrinse vehicle) was associated with a reduction in plaque and salivary S. mutans, lactic acid production, and enamel demineralization during the entire 4-day testing period. C16G2 is now being developed as a new anticaries drug.

10% chlorhexidine varnish did not reduce caries in an adult population

DESIGN

A multi-centre, placebo-controlled, double-blind, randomised clinical trial involving 983 adults (aged 18-80 years old).

INTERVENTION

The test group received chlorhexidine diacetate 10% weight per volume (w/v) dental coating and the control group received a placebo coating. Coatings were applied weekly for four weeks and a fifth time six months later.

OUTCOME MEASURE

The Pitts and Fyffe taxonomy was used to measure caries progression or reversal, which identifies three stages of lesion on coronal surfaces. The primary outcome was the total net increment in D(1-2)FS; secondary outcomes included the cumulative net D(1-2)FS increment and the total crude D(1-2)FS increment and the cumulative crude D(1-2)FS increment.

RESULTS

No significant difference was seen between the treatment and placebo groups over a 13 month study period.

CONCLUSIONS

Ten percent chlorhexidine diacetate coating did not show a reduction in caries in an adult population.

Efficacy of chlorhexidine varnish for the prevention of adult caries: a randomized trial

The Prevention of Adult Caries Study, an NIDCR-funded multicenter, double-blind, randomized clinical trial, enrolled 983 adults (aged 18-80 yrs) at high risk for developing caries (20 or more intact teeth and 2 or more lesions at screening) to test the efficacy of a chlorhexidine diacetate 10% weight per volume (w/v) dental coating (CHX). We excluded participants for whom the study treatment was contraindicated or whose health might affect outcomes or ability to complete the study. Participants were randomly assigned to receive either the CHX coating (n = 490) or a placebo control (n = 493). Coatings were applied weekly for 4 weeks and a fifth time 6 months later. The primary outcome (total net D(1-2)FS increment) was the sum of weighted counts of changes in tooth surface status over 13 months. We observed no significant difference between the two treatment arms in either the intention-to-treat or per-protocol analyses. Analysis of 3 protocol-specified secondary outcomes produced similar findings. This trial failed to find that 10% (w/v) chlorhexidine diacetate coating was superior to placebo coating for the prevention of new caries (Clinicaltrials.gov registration number NCT00357877).

Clinical efficacy of a specifically targeted antimicrobial peptide mouth rinse: targeted elimination of Streptococcus mutans and prevention of demineralization

BACKGROUND/AIMS

Streptococcus mutans, the major etiological agent of dental caries, has a measurable impact on domestic and global health care costs. Though persistent in the oral cavity despite conventional oral hygiene, S. mutans can be excluded from intact oral biofilms through competitive exclusion by other microorganisms. This suggests that therapies capable of selectively eliminating S. mutans while limiting the damage to the normal oral flora might be effective long-term interventions to fight cariogenesis. To meet this challenge, we designed C16G2, a novel synthetic specifically targeted antimicrobial peptide with specificity for S. mutans. C16G2 consists of a S. mutans-selective 'targeting region' comprised of a fragment from S. mutans competence stimulation peptide (CSP) conjoined to a 'killing region' consisting of a broad-spectrum antimicrobial peptide (G2). In vitro studies have indicated that C16G2 has robust efficacy and selectivity for S. mutans, and not other oral bacteria, and affects targeted bacteria within seconds of contact.

METHODS

In the present study, we evaluated C16G2 for clinical utility in vitro, followed by a pilot efficacy study to examine the impact of a 0.04% (w/v) C16G2 rinse in an intra-oral remineralization/demineralization model.

RESULTS AND CONCLUSIONS

C16G2 rinse usage was associated with reductions in plaque and salivary S. mutans, lactic acid production, and enamel demineralization. The impact on total plaque bacteria was minimal. These results suggest that C16G2 is effective against S. mutans in vivo and should be evaluated further in the clinic.