Research Abstracts - Prevention

OBJECTIVES: This study investigated the biofilm removal capacity of two ultrasonic tips under standardized conditions using a multi-species biofilm model.
METHODS: Six-species biofilms were grown on hydroxyapatite discs for 64.5 h and treated for 15 s with a standardized load of 40 g with a piezoelectric or magnetostrictive device. Tips were applied either with the tip end or with the side facing downwards. Detached bacteria were determined in the supernatant and colony-forming units (CFUs) counted after 72 h of incubation. Untreated specimens served as controls. Moreover, the biofilms remaining on the hydroxyapatite surface after treatment were stained using the Live/Dead stain, and their detachment pattern was assessed by confocal laser scanning microscopy (CLSM).
RESULTS: Compared to the untreated control, only a side application of the magnetostrictive device was able to efficiently remove the biofilm. In contrast, its tip application as well as both applications of the piezoelectric device removed significantly less bacteria from the biofilm structure.
CONCLUSION: Both ultrasonic tips led to bacterial detachment, but the action mode as well as the tip configuration and adaptation appeared to be influenced by the biofilm removal effectiveness. The presented combination of methods applied on a multi-species biofilm model in vitro allows the evaluation of the effectiveness of different ultrasonic scaler applications.

It is critical that dental practitioners effectively treat patients who suffer from periodontal disease. This well-designed research study evaluated and compared biofilm (bacteria) removal using both piezoelectric and magnetostrictive ultrasonic scalers. It demonstrated that effectiveness in removing biofilm is device-specific. The orientation of the instrument working ends plays a significant role. In this study, the Cavitron Select SPS used in side application was significantly more effective in debriding biofilm from the specimens than its tip application or the piezoelectric device (either tip application or side application). Dentists and dental hygienists need to understand that the term ultrasonic scaler should not be generalized between devices for the effectiveness of clinical results desired.

Mittal A, Nichani AS, Venugopal R, Rajani V. J Indian Soc Periodontol. 2014;18(6):710-717.

BACKGROUND: This study compared the effectiveness of different ultrasonic scalers and a periodontal curette on the root surfaces for calculus removal and root surface roughness.
METHODS: Forty single-rooted teeth with subgingival calculus destined for extraction were assigned to one of three experimental groups (n = 10, in each group) and one control group (n = 10, untreated). Experimental groups were: piezoelectric ultrasonic group; magnetostrictive ultrasonic group; and hand instrumentation group (curette). After instrumentation, the teeth were extracted and the presence of residual deposits and root surface roughness were analyzed using a Planimetric analyzing tool and Surface Profilometer. Root surface characteristics were evaluated qualitatively using scanning electron microscope (SEM).
RESULTS: Residual deposits were similar in all experimental groups. With respect to roughness parameters, a significant difference was observed among hand instrumentation and ultrasonic devices. SEM analysis revealed a similar root surface pattern for the ultrasonic devices, but curette produced rougher root surfaces, instrument scratches, and removal of large amounts of cementum. Piezoelectric devices produced minimum root surface roughness but caused more root substance removal and more cracks.

The goal of periodontal procedures is to remove bacterial plaque, calculus, and infected root cementum while producing a smooth surface with minimal damage to the root. This study compared different ultrasonic scalers and hand scaling using established evaluation techniques. All techniques significantly removed stained deposits; however, the curette created more damage to root surfaces. The piezoelectric scaler caused greater loss of dentin than the magnetostrictive device. For patients, more aggressive loss of cementum and damage to the root can be responsible for increased rates of postoperative dentin-root hypersensitivity. Care needs to be taken when using hand instrumentation to supplement the use of ultrasonic devices when removing deposits and creating smooth root surfaces.

Fratolin MM, Bianco VC, Santos MJ, et al. Compend Contin Educ Dent. 2014;35(9):e31-e35.

OBJECTIVE: The aim of this study was to assess the effect of dental prophylactic methods on the surface roughness of enamel.
METHODS: Enamel specimens (150) were sectioned from human molars and mounted on resin bases. This work consisted of two parts. In the first, there were eight groups (n = 15): three treated with two air-polishing devices (AP)—LM-ProPower AirLED (Mode 1 and 2) and EMS Air-Flow Handy 2—for 30 seconds and sodium bicarbonate prophylactic powder, and three treated with the two APs using microsphere calcium carbonate prophylactic powder. The seventh group was treated with rubber-cup polishing using medium and fine grits, and the eighth (control) was enamel with no surface treatment. In the second part of the work, two groups (n = 15) were subjected to treatment with the LM unit (Mode 2) and each of the abrasive powders for 5 seconds. Surface roughness (Ra) of samples was assessed using a mechanical stylus profilometer and SEM. Statistical analysis of the data was conducted using two-way ANOVA and Tukey HSD (honest significant difference) rank order test at P = 0.05.
RESULTS: Both prophylactic methods resulted in a statistically significant increase in surface roughness when compared to untreated specimens. All air-abrasive treatments for 30 seconds resulted in an increase in roughness compared to rubber-cup prophylaxis. However, AP with calcium carbonate and the sodium bicarbonate for 5 seconds produced results that were not significantly different from rubber-cup prophylaxis. CONCLUSION: Both types of prophylactic dental cleaning have an effect on surface roughness. The abrasiveness of APs depends upon the length of treatment and the type of powder used.

Patients associate dental cleanings with a whiter and brighter smile. A routine dental prophylaxis removes plaque and stain from teeth with scaling and root planing, rubber-cup polishing, and air polishing (AP). Not damaging tooth surfaces is always a concern. This study provides a comparative analysis of potential enamel damage and roughening. Tooth surface roughness can lead to increased plaque buildup and calculus retention. Rubber-cup polishing does the least damage. While AP appears to be the same with all devices and abrasive powders, in fact the duration of air polishing and type of powder makes a difference. This research provides insight into better practices when using an AP. The sodium bicarbonate powder (LM-ProPower) did less damage than the calcium carbonate. Also, use of an AP should be only for the least amount of time needed to accomplish the result desired, and the dental prophylaxis should be finished with rubber-cup polishing.

Lee BS, Chou PH, Chen SY, et al. Sci Rep. 2015 Aug 21;5:13352. doi: 10.1038/srep13352.

OBJECTIVES: There is no topically applicable low-concentration fluoride delivery device available for caries prevention. Slow-release devices of low-level fluoride are regarded as a potential method to elevate fluoride concentration at the biofilm/saliva/dental interface and inhibit dental caries. The objective of this study was to assess the use of a low-concentration (1450 ppm) fluoride strip as an effective fluoride delivery system against enamel demineralization.
METHODS: The enamel surface composition and calcium-deficient hydroxyapatite or toothpaste treatments were investigated using x-ray photoelectron spectroscopy. In vitro enamel demineralization was assayed using a pH cycling model, and the dissolution of calcium ions from the treated specimens was quantified using ion chromatography. After 24-hr fluoride-strip treatment, the enamel was covered with a calcium fluoride (CaF2) layer, which showed a granular morphology of 1 μm in size. Below the CaF2 layer was a region of mixed fluorapatite and CaF2.
RESULTS: Fluoride infiltrated extensively in enamel to produce highly fluorinated fluorohydroxyapatite. In comparison, low-fluoride-level fluorinated fluorohydroxyapatite was formed on the enamel specimen exposed to toothpaste. The treatments with the fluoride strip as short as 1 hr significantly inhibited enamel demineralization. The fluoride strip was effective for topical fluoride delivery and inhibited in vitro demineralization of enamel by forming CaF2 and fluoride-containing apatites at the enamel surface.
CONCLUSION: The low-concentration fluoride strip exhibited the potential as an effective fluoride delivery device for general use in prevention of caries.

Dental caries, a bacterially caused demineralization of the tooth structure, continues to be one of the most significant infectious diseases, affecting approximately 36% of the world’s population. In fact, nearly all adults will have dental caries at some point in their lives. Fluoride has been successfully used as an effective preventive measure against caries. High-concentration fluoride treatments are used in dental practices. At-home topical application of fluoride is limited to toothpastes and fluoride rinses with relatively short duration therapeutic effects. This study presents a novel slow-release, low-concentration fluoride-containing strip technique that was effective over 24 hours. This is an exciting technology that has potential to impact dentistry. For the future, the challenges for this system will be clinical trials to show its effectiveness, as well as the cost equivalencies to current products and patient acceptance of this therapeutic technique.

Rolnick SJ, Jackson JM, DeFor TA, Flottemesch TJ. J Clin Pediatr Dent. 2015;39(4):311-314.

OBJECTIVES: The study objectives were twofold: to examine how an intervention to apply fluoride varnish (FV) in a primary health setting to all young, low-income children was implemented and sustained; and to assess the feasibility of tracking medical care utilization in this population.
STUDY DESIGN: The study included children age 1 through 5, insured through a government program, seen (7/1/2010-4/30/2012). Data on age, race, sex, clinic encounter, and eligibility for and receipt of FV was obtained. The level of data in primary care, specialty care, urgent care, and hospitalizations to assess feasibility of future patient tracking was also acquired. RESULTS: Of 12,067 children, 85% received FV. Differences were found by age (youngest had highest rates). Small differences by race (81% to 88%, highest in Blacks) was found. No differences were found by sex. Ability to track over time was mixed. Approximately 50% had comprehensive data. However, primary care visit and hospitalization data was available on a larger percentage.
CONCLUSIONS: FV programs can be introduced in the primary care setting and sustained. Further, long-term follow up is possible. Future study of such cohorts capturing health and cost benefits of oral health prevention efforts is needed.

Recent data has shown steady growth in dental utilization by children due to increased public coverage programs, and in many cases children in families with low incomes are being seen for treatment of caries. Can preventive services for these children be provided earlier in their lives? An effective preventive service for young children is the use of fluoride varnish (FV). This study demonstrated that FV applications in medical settings can be cost effective over a patient’s lifetime. It demonstrates that FV programs in a primary care setting can be sustained. A substantial benefit of FV is that it takes less time to apply and results in fewer problems to younger children. Local dental societies and organizations need to have initiatives to educate medical professionals so they can incorporate FV programs into their primary care practices.

Jose A, Butler A, Payne D, et al. Br Dent J. 2015;219(3):125-130.

OBJECTIVES: Gingival bleeding following twice-daily use of 0.2% w/v chlorhexidine digluconate mouthrinse with and without alcohol (0.2% CHX-alcohol; 0.2% CHX-alcohol-free, respectively) and brushing with a standard fluoride toothpaste was compared to brushing alone.
METHODS: A total of 319 subjects with mild-to-moderate gingivitis completed this randomized, examiner-blinded, parallel-group study. A prophylaxis was performed at baseline. Gingival Severity Index (GSI; primary objective), Gingival Index (GI), and Plaque Index (PI) were assessed at baseline and after 6 weeks of treatment. Adverse events were recorded throughout. RESULTS: Between treatment differences at week 6 demonstrated significantly lower GSI for the 0.2% CHX-alcohol and 0.2% CHX-alcohol-free groups compared to brushing alone (primary endpoint; treatment difference -0.061 [95% CI -0.081, -0.041] and -0.070 [95% CI -0.090, -0.050], respectively; both P < 0.0001). There were also significant reductions in GI and PI for the 0.2% CHX-alcohol and 0.2% CHX-alcohol-free groups compared to brushing alone (all P < 0.0001). The proportion of subjects reporting ≥1 treatment-related adverse events (TRAEs) was 27.8% (0.2% CHX-alcohol), 24.8% (0.2% CHX-alcohol-free), and 3.7% (brushing alone).
CONCLUSIONS: Chlorhexidine mouthrinse with or without alcohol as an adjunct to brushing with regular fluoride toothpaste significantly reduces bleeding scores, plaque, and gingival inflammation compared to brushing alone. TRAEs are characteristic of those associated with the use of chlorhexidine and are similar for both mouthrinses.

While brushing with toothpaste and flossing are dependable methods to control gingival bleeding, these techniques rely upon patients being able to brush and floss in a way that will effectively remove bacterial plaque. Unfortunately, despite the best efforts of clinicians to provide patients with good oral hygiene instructions, they are not always well heeded. A number of studies have shown that the maintenance of improved gingival health over long periods of time requires prolonged, repeated instruction by professionals. This can be a significant challenge. This study provides an additional tool in the clinician’s oral health toolbox. By prescribing the use of a chlorhexidine mouthrinse as part of the usual oral hygiene regimen, there is potential to achieve a more positive oral health outcome than with brushing and flossing alone. Also, for those patients who are alcohol adverse, an alcohol-free chlorhexidine works as effectively.