Powered versus manual toothbrushing for oral health.

BACKGROUND: Removing dental plaque may play a key role maintaining oral health. There is conflicting evidence for the relative merits of manual and powered toothbrushing in achieving this. This is an update of a Cochrane review first published in 2003, and previously updated in 2005. OBJECTIVES: To compare manual and powered toothbrushes in everyday use, by people of any age, in relation to the removal of plaque, the health of the gingivae, staining and calculus, dependability, adverse effects and cost. SEARCH METHODS: We searched the following electronic databases: the Cochrane Oral Health Group's Trials Register (to 23 January 2014), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 1), MEDLINE via OVID (1946 to 23 January 2014), EMBASE via OVID (1980 to 23 January 2014) and CINAHL via EBSCO (1980 to 23 January 2014). We searched the US National Institutes of Health Trials Register and the WHO Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: Randomised controlled trials of at least four weeks of unsupervised powered toothbrushing versus manual toothbrushing for oral health in children and adults. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by The Cochrane Collaboration. Random-effects models were used provided there were four or more studies included in the meta-analysis, otherwise fixed-effect models were used. Data were classed as short term (one to three months) and long term (greater than three months). MAIN RESULTS: Fifty-six trials met the inclusion criteria; 51 trials involving 4624 participants provided data for meta-analysis. Five trials were at low risk of bias, five at high and 46 at unclear risk of bias.There is moderate quality evidence that powered toothbrushes provide a statistically significant benefit compared with manual toothbrushes with regard to the reduction of plaque in both the short term (standardised mean difference (SMD) -0.50 (95% confidence interval (CI) -0.70 to -0.31); 40 trials, n = 2871) and long term (SMD -0.47 (95% CI -0.82 to -0.11; 14 trials, n = 978). These results correspond to an 11% reduction in plaque for the Quigley Hein index (Turesky) in the short term and 21% reduction long term. Both meta-analyses showed high levels of heterogeneity (I(2) = 83% and 86% respectively) that was not explained by the different powered toothbrush type subgroups.With regard to gingivitis, there is moderate quality evidence that powered toothbrushes again provide a statistically significant benefit when compared with manual toothbrushes both in the short term (SMD -0.43 (95% CI -0.60 to -0.25); 44 trials, n = 3345) and long term (SMD -0.21 (95% CI -0.31 to -0.12); 16 trials, n = 1645). This corresponds to a 6% and 11% reduction in gingivitis for the Löe and Silness index respectively. Both meta-analyses showed high levels of heterogeneity (I(2) = 82% and 51% respectively) that was not explained by the different powered toothbrush type subgroups.The number of trials for each type of powered toothbrush varied: side to side (10 trials), counter oscillation (five trials), rotation oscillation (27 trials), circular (two trials), ultrasonic (seven trials), ionic (four trials) and unknown (five trials). The greatest body of evidence was for rotation oscillation brushes which demonstrated a statistically significant reduction in plaque and gingivitis at both time points. AUTHORS' CONCLUSIONS: Powered toothbrushes reduce plaque and gingivitis more than manual toothbrushing in the short and long term. The clinical importance of these findings remains unclear. Observation of methodological guidelines and greater standardisation of design would benefit both future trials and meta-analyses.Cost, reliability and side effects were inconsistently reported. Any reported side effects were localised and only temporary.

Characterisation of bone following ultrasonic cutting.

OBJECTIVES: Ultrasonic surgery is an increasingly popular technique for cutting bone, but little research has investigated how the ultrasonic tip oscillations may affect the cuts they produce in bone. The aim of this investigation was to evaluate the oscillation and cutting characteristics of an ultrasonic surgical device. MATERIALS AND METHODS: A Piezosurgery 3 (Mectron, Carasco, Italy) ultrasonic cutting system was utilised with an OP3 style tip. The system was operated with the tip in contact with porcine bone samples (loads of 50 to 200 g) mounted at 45° to the vertical insert tip and with a water flow of 57 ml/min. Tip oscillation amplitude was determined using scanning laser vibrometry. Bone surfaces defects were characterised using laser profilometry and scanning electron microscopy. RESULTS: A positive relationship was observed between the magnitude of tip oscillations and the dimensions of defects cut into the bone surface. Overloading the tip led to a reduction in oscillation and hence in the defect produced. A contact load of 150 g provided the greatest depth of cut. Defects produced in the bone came from two clear phases of cutting. CONCLUSIONS: The structure of the bone was found to be an important factor in the cut characteristics following piezosurgery. CLINICAL RELEVANCE: Cutting of bone with ultrasonics is influenced by the load applied and the setting used. Care must be used to prevent the tip from sliding over the bone at low loadings.

Mapping cavitation activity around dental ultrasonic tips.

OBJECTIVES: Cavitation arising within the water around the oscillating ultrasonic scaler tip is an area that may lead to advances in enhancing biofilm removal. The aim of this study is to map the occurrence of cavitation around scaler tips under loaded conditions. MATERIALS AND METHODS: Two designs of piezoelectric ultrasonic scaling probes were evaluated with a scanning laser vibrometer and luminol dosimetric system under loaded (100 g/200 g) and unloaded conditions. Loads were applied to the probe tips via teeth mounted in a load-measuring apparatus. RESULTS: There was a positive correlation between probe displacement amplitude and cavitation production for ultrasonic probes. The position of cavitation at the tip of each probe was greater under loaded conditions than unloaded and for the longer P probe towards the tip. CONCLUSIONS: Whilst increasing vibration displacement amplitude of ultrasonic scalers increases the occurrence of cavitation, factors such as the length of the probe influence the amount of cavitation activity generated. The application of load affects the production of cavitation at the most clinically relevant area-the tip. CLINICAL RELEVANCE: Loading and the design of ultrasonic scalers lead to maximising the occurrence of the cavitation at the tip and enhance the cleaning efficiency of the scaler.

Differing responses of osteogenic cell lines to ß-glycerophosphate.

Ascorbic acid (Asc), dexamethasone (Dex) and ß-glycerophosphate (ß-Gly) are commonly used to promote osteogenic behaviour by osteoblasts in vitro. According to the literature, several osteosarcoma cells lines appear to respond differently to the latter with regards to proliferation kinetics and osteogenic gene transcription. Unsurprisingly, these differences lead to contrasting data between publications that necessitate preliminary studies to confirm the phenotype of the chosen osteosarcoma cell line in the presence of Asc, Dex and ß-Gly. The present study exposed Saos-2 cells to different combinations of Asc, Dex and ß-Gly for 14 days and compared the response with immortalised human mesenchymal stromal/stem cells (MSCs). Cell numbers, cytotoxicity, mineralised matrix deposition and cell proliferation were analysed to assess osteoblast-like behaviour in the presence of Asc, Dex and ß-Gly. Additionally, gene expression of runt-related transcription factor 2 (RUNX2); osteocalcin (OCN); alkaline phosphatase (ALP); phosphate regulating endopeptidase homolog X-linked (PHEX); marker of proliferation MKI67 and proliferating cell nuclear antigen (PCNA) was performed every two days during the 14-day cultures. It was found that proliferation of Saos-2 cells was significantly decreased by the presence of ß-Gly which contrasted with hMSCs where no change was observed. Furthermore, unlike hMSCs, Saos-2 cells demonstrated an upregulated expression of late osteoblastic markers, OCN and PHEX that suggested ß-Gly could affect later stages of osteogenic differentiation. In summary, it is important to consider that ß-Gly significantly affects key cell processes of Saos-2 when using it as an osteoblast-like cell model.

Sectional dentures revisited.

UNLABELLED: Sectional dentures are constructed in separate parts which join together intra-orally to create a single prosthesis. They are used to exploit undercuts around teeth, hard and soft tissues which require more than one path of insertion, and are usually of split pin or locking bolts design. By using two case studies, we aim to illustrate the provision of sectional dentures and to which situations their uses are best suited. A 30-year-old male was referred to the Department of Prosthetics at the Birmingham Dental Hospital for a replacement upper partial cobalt chrome denture of a Kennedy Class IV bounded saddle. The patient had a history of failed upper cobalt chrome removable partial dentures owing to loss of retention and poor stability over the previous 12 months. A 40-year-old female patient was referred by her GDP for restoration of a bounded saddle in the lower right quadrant with a history of intolerance to previous dentures. These two cases demonstrate the successful use of sectional dentures in the aesthetic zone. Although more technically demanding, they lie well within the scope of general practice and offer patients alternative solutions from dental implants and bridgework. These cases highlight the importance of the use of alternative prosthetic techniques which can be simple and achievable for all practitioners. CLINICAL RELEVANCE: Sectional dentures are a treatment modality for the edentulous space where the presence of one or more undercuts prevents restoration by more conventional techniques. This paper highlights some of the situations in which sectional dentures can be employed and emphasizes their use in general practice.

Exploring the neurogenic differentiation of human dental pulp stem cells.

Human dental pulp stem cells (hDPSCs) have increasingly gained interest as a potential therapy for nerve regeneration in medicine and dentistry, however their neurogenic potential remains a matter of debate. This study aimed to characterize hDPSC neuronal differentiation in comparison with the human SH-SY5Y neuronal stem cell differentiation model. Both hDPSCs and SH-SY5Y could be differentiated to generate typical neuronal-like cells following sequential treatment with all-trans retinoic acid (ATRA) and brain-derived neurotrophic factor (BDNF), as evidenced by significant expression of neuronal proteins ßIII-tubulin (TUBB3) and neurofilament medium (NF-M). Both cell types also expressed multiple neural gene markers including growth-associated protein 43 (GAP43), enolase 2/neuron-specific enolase (ENO2/NSE), synapsin I (SYN1), nestin (NES), and peripherin (PRPH), and exhibited measurable voltage-activated Na+ and K+ currents. In hDPSCs, upregulation of acetylcholinesterase (ACHE), choline O-acetyltransferase (CHAT), sodium channel alpha subunit 9 (SCN9A), POU class 4 homeobox 1 (POU4F1/BRN3A) along with a downregulation of motor neuron and pancreas homeobox 1 (MNX1) indicated that differentiation was more guided toward a cholinergic sensory neuronal lineage. Furthermore, the Extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor U0126 significantly impaired hDPSC neuronal differentiation and was associated with reduction of the ERK1/2 phosphorylation. In conclusion, this study demonstrates that extracellular signal-regulated kinase/Mitogen-activated protein kinase (ERK/MAPK) is necessary for sensory cholinergic neuronal differentiation of hDPSCs. hDPSC-derived cholinergic sensory neuronal-like cells represent a novel model and potential source for neuronal regeneration therapies.

Traditional Multiwell Plates and Petri Dishes Limit the Evaluation of the Effects of Ultrasound on Cells In Vitro.

Ultrasound accelerates healing in fractured bone; however, the mechanisms responsible are poorly understood. Experimental setups and ultrasound exposures vary or are not adequately characterized across studies, resulting in inter-study variation and difficulty in concluding biological effects. This study investigated experimental variability introduced through the cell culture platform used. Continuous wave ultrasound (45 kHz; 10, 25 or 75 mW/cm2, 5 min/d) was applied, using a Duoson device, to Saos-2 cells seeded in multiwell plates or Petri dishes. Pressure field and vibration quantification and finite-element modelling suggested formation of complex interference patterns, resulting in localized displacement and velocity gradients, more pronounced in multiwell plates. Cell experiments revealed lower metabolic activities in both culture platforms at higher ultrasound intensities and absence of mineralization in certain regions of multiwell plates but not in Petri dishes. Thus, the same transducer produced variable results in different cell culture platforms. Analysis on Petri dishes further revealed that higher intensities reduced vinculin expression and distorted cell morphology, while causing mitochondrial and endoplasmic reticulum damage and accumulation of cells in sub-G1 phase, leading to cell death. More defined experimental setups and reproducible ultrasound exposure systems are required to study the real effect of ultrasound on cells for development of effective ultrasound-based therapies not just limited to bone repair and regeneration.

Cutting characteristics of ultrasonic surgical instruments.

OBJECTIVE: Ultrasonic surgical devices are becoming increasingly popular and work is required to understand the performance of the cutting tips. This experimental study looks to investigate the way in which ultrasonic bone cutting tools oscillate and how this oscillation is modified when contacted against bone surfaces with varying loads. The defects produced in instrumented bone surfaces were measured and related to the tip motion. METHODS: An ultrasonic cutting probe was scanned, unloaded, using a scanning laser vibrometer to determine its free oscillation pattern and amplitude. This probe tip was then contacted against bone under various loads to assess the modification in oscillation characteristics. Cuts were performed over a period of 10 s. The cut bone surfaces were assessed using laser profilometry to determine defect depths. RESULTS: The average vibration displacement amplitude at the probe tip, under load, was <12 µm in the longitudinal direction and was greatest for the cortical cutting mode. Elliptical probe motion was successfully mapped out under the range of loads tested. Defect depths of up to 0.36 mm were detected and were greatest when the tip was in contact with the bone with a load of 100 g. CONCLUSIONS: This work showed that the nature of the surface being cut may significantly alter the mode shape and magnitude of the probe oscillation. The maximum depth of cut with minimum restraining of tip motion was achieved at 100 g contact load.

Treatment options for the free end saddle.

UNLABELLED: Many treatment options are available for the management of the free end saddle. This paper reviews past and current treatment methods for management of this situation. CLINICAL RELEVANCE: To understand the problem posed by the free end saddle and the techniques available to clinicians for its management in general dental practice.

Biofilm viability checker: An open-source tool for automated biofilm viability analysis from confocal microscopy images.

Quantifying biofilm formation on surfaces is challenging because traditional microbiological methods, such as total colony-forming units (CFUs), often rely on manual counting. These are laborious, resource intensive techniques, more susceptible to human error. Confocal laser scanning microscopy (CLSM) is a high-resolution technique that allows 3D visualisation of biofilm architecture. In combination with a live/dead stain, it can be used to quantify biofilm viability on both transparent and opaque surfaces. However, there is little consensus on the appropriate methodology to apply in confocal micrograph processing. In this study, we report the development of an image analysis approach to repeatably quantify biofilm viability and surface coverage. We also demonstrate its use for a range of bacterial species and translational applications. This protocol has been created with ease of use and accessibility in mind, to enable researchers who do not specialise in computational techniques to be confident in applying these methods to analyse biofilm micrographs. Furthermore, the simplicity of the method enables the user to adapt it for their bespoke needs. Validation experiments demonstrate the automated analysis is robust and accurate across a range of bacterial species and an improvement on traditional microbiological analysis. Furthermore, application to translational case studies show the automated method is a reliable measurement of biomass and cell viability. This approach will ensure image analysis is an accessible option for those in the microbiology and biomaterials field, improve current detection approaches and ultimately support the development of novel strategies for preventing biofilm formation by ensuring comparability across studies.

Different powered toothbrushes for plaque control and gingival health.

BACKGROUND: Powered brushes were first introduced commercially in the 1960s. A recent systematic review suggested the superiority of certain modes of powered over manual toothbrushing for plaque and gingivitis reduction. That review did not allow for direct comparison between different modes of powered toothbrush. OBJECTIVES: To compare different modes of powered toothbrushing against each other for plaque reduction and the health of the gingivae. Other factors to be assessed were calculus and stain removal, cost, dependability and adverse effects. SEARCH STRATEGY: The following databases were searched: Cochrane Oral Health Group's Trials Register (to 26 July 2010); Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 3); MEDLINE via OVID (1950 to 26 July 2010); EMBASE via OVID (1980 to 26 July 2010); CINAHL via EBSCO (1982 to 26 July 2010). There were no language restrictions. SELECTION CRITERIA: Trials were considered for inclusion with the following criteria: random allocation of participants; no compromised manual dexterity; unsupervised powered toothbrushing for at least 4 weeks. The primary outcomes were the plaque and gingivitis scores after powered toothbrush use during trial period. DATA COLLECTION AND ANALYSIS: Data extraction was performed independently and in duplicate. The authors of trials were contacted to provide missing data where possible. The effect measure for each meta-analysis was the standardised mean difference (SMD) with 95% confidence intervals (CI) using the random-effects model. Potential sources of heterogeneity were assessed. MAIN RESULTS: The review included data from 15 trials with 1015 participants. Due to the dearth of trials assessing the same mode of action, no definitive conclusions can be stated regarding the superiority of one mode of powered toothbrush over any other. Only minor and transient side effects were reported. Cost, dependability were not reported. AUTHORS' CONCLUSIONS: Further trials of good quality are required to establish if any mode of action has superiority over the other modes of action for powered toothbrushes.

Imaging and Quantification of the Area of Fast-Moving Microbubbles Using a High-Speed Camera and Image Analysis.

An experimental and image analysis technique is presented for imaging cavitation bubbles and calculating their area. The high-speed imaging experimental technique and image analysis protocol presented here can also be applied for imaging microscopic bubbles in other fields of research; therefore, it has a wide range of applications. We apply this to image cavitation around dental ultrasonic scalers. It is important to image cavitation to characterize it and to understand how it can be exploited for various applications. Cavitation occurring around dental ultrasonic scalers can be used as a novel method of dental plaque removal, which would be more effective and cause less damage than current periodontal therapy techniques. We present a method for imaging the cavitation bubble clouds occurring around dental ultrasonic scaler tips using a high-speed camera and a zoom lens. We also calculate the area of cavitation using machine learning image analysis. Open source software is used for image analysis. The image analysis presented is easy to replicate, does not require programming experience, and can be modified easily to suit the application of the user.

High speed imaging of biofilm removal from a dental implant model using ultrasonic cavitation.

OBJECTIVES: Current instruments cannot clean in between dental implant threads and effectively remove biofilm from the rough implant surface without damaging it. Cavitation bubbles have the potential to disrupt biofilms. The aim of this study was to see how biofilms can be disrupted using non-contact cavitation from an ultrasonic scaler, imaged inside a restricted implant pocket model using high speed imaging. METHODS: Streptococcus sanguinis biofilm was grown for 7 days on dental implants. The implants were placed inside a custom made restricted pocket model and immersed inside a water tank. An ultrasonic scaler tip was placed 0.5mm away from the implant surface and operated at medium power or high power for 2s. The biofilm removal process was imaged using a high speed camera operating at 500 fps. Image analysis was used to calculate the amount of biofilm removed from the high speed images. Scanning electron microscopy was done to visualize the implant surface after cleaning. RESULTS: Cavitation was able to remove biofilm from dental implants. More biofilm was removed at high power. Scanning electron microscopy showed that the implant surface was clean at the points where the cavitation was most intense. High speed imaging showed biofilm removal underneath implant threads, in areas next to the ultrasonic scaler tip. SIGNIFICANCE: A high speed imaging protocol has been developed to visualize and quantify biofilm removal from dental implants in vitro. Cavitation bubbles from dental ultrasonic scalers are able to successfully disrupt biofilm in between implant threads.

Mechano-physical and biophysical properties of power-driven scalers: driving the future of powered instrument design and evaluation.

This review has highlighted the importance of standardizing future investigations to enable more meaningful interstudy comparisons to be made. This report also makes recommendations for factors that should be considered and incorporated into future investigations, both in vitro and in vivo, in order to achieve more standardization. These recommendations are listed below.

Three-dimensional analyses of ultrasonic scaler oscillations.

BACKGROUND: It is stated that the oscillation patterns of dental ultrasonic scalers are dependent upon whether the instrument is of a magnetostrictive or piezoelectric design. These patterns are then linked to differences in root surface debridement in vitro. MATERIAL AND METHODS: Piezoelectric (A, P) and magnetostrictive (Slimline, TFI-3) ultrasonic scalers (three of each) were evaluated, loaded (100 g/200 g) and unloaded with a 3D laser vibrometer. Loads were applied to the probe tips via teeth mounted in a load-measuring device. RESULTS: Elliptical motion was demonstrated for all probes under loaded and unloaded conditions. Loading flattened the elliptical motion along the length of the probe. Unloaded, Slimline tip 1 was significantly different to tips 2 and 3 (p<0.0001). There were no differences between the A-tips (p>0.207). All TFI-3 tips were different to each other (p<0.0001). P-tips 1 and 2 were different to each other (p=0.046). Loaded, Slimline tips were different to each other (p<0.001). There were no differences between the P probes (p>0.867). Generator power increased all Slimline and P tip vibrations (p<0.0001). CONCLUSIONS: Probe oscillation patterns are independent of ultrasound production mechanism and are dependent upon probe shape and generator power. Loaded probes oscillated with an elliptical pattern.

Which Parameters Affect Biofilm Removal with Acoustic Cavitation? A Review.

Bacterial biofilms are a cause of contamination in a wide range of medical and biological areas. Ultrasound is a mechanical energy that can remove these biofilms using cavitation and acoustic streaming, which generate shear forces to disrupt biofilm from a surface. The aim of this narrative review is to investigate the literature on the mechanical removal of biofilm using acoustic cavitation to identify the different operating parameters affecting its removal using this method. The properties of the liquid and the properties of the ultrasound have a large impact on the type of cavitation generated. These include gas content, temperature, surface tension, frequency of ultrasound and acoustic pressure. For many of these parameters, more research is required to understand their mechanisms in the area of ultrasonic biofilm removal, and further research will help to optimise this method for effective removal of biofilms from different surfaces.

Advances in power driven pocket/root instrumentation.

OBJECTIVES: The primary aim was: "Does power-driven pocket/root instrumentation offer a clinical advantage over hand instrumentation"? Secondary aim was to update knowledge base of power-driven instrumentation post Tunkel et al. (2002). MATERIAL AND METHODS: A literature search of power-driven instruments (in vitro, in vivo and controlled clinical trials) was performed from April 2001 using similar criteria to Tunkel et al. (2002). Primary outcome was whether power-driven instruments offered an advantage over hand instrumentation; secondary outcomes were effect on root surface, effectiveness of new instrument designs, and role of biophysical effects such as cavitation. RESULTS: From a total of 41 studies, 14 studies involved comparison of power-driven devices with hand instrumentation for non-surgical therapy. These were subdivided into new designs of power instrumentation, full-mouth debridement and irrigation and patient acceptance. Use of power-driven instrumentation provides similar clinical outcomes compared with hand instrumentation. Difficulty of pooling studies continues to hinder the drawing of definitive conclusions. CONCLUSION: Newer designs of powered instruments have not shown any benefit when compared with other ultrasonic devices in non-surgical periodontal therapy. New in vitro research shows there is variation in the performance of different tip designs and generators, but its clinical relevance remains unknown.

Vibration characteristics of dental high-speed turbines and speed-increasing handpieces.

OBJECTIVES: Vibrations of dental handpieces may contribute to symptoms of hand-arm vibration syndrome in dental personnel and iatrogenic enamel cracking in teeth. However, methods for measuring dental handpiece vibrations have previously been limited and information about vibration characteristics is sparse. This preliminary study aimed to use a novel approach to assess the vibrations of unloaded high-speed handpieces in vitro. METHODS: Maximum vibration displacement amplitudes of five air turbines and two speed-increasing handpieces were recorded whilst they were operated with and without a rotary cutting instrument (RCI) using a scanning laser vibrometer (SLV). RESULTS: RCI rotation speeds, calculated from frequency peaks, were consistent with expected values. ANOVA statistical analysis indicated significant differences in vibrations between handpiece models (p<0.01), although post hoc tests revealed that differences between most individual models were not significant (p>0.11). Operating handpieces with a RCI resulted in greater vibrations than with no RCI (p<0.01). Points on the head of the handpiece showed greater vibration displacement amplitudes than points along the body (p<0.01). CONCLUSIONS: Although no single measurement exceeded 4 microm for the handpieces in the current test setup (implying that these vibrations may be unlikely to cause adverse effects), this study has formed the basis for future work which will include handpiece vibration measurements whilst cutting under clinically representative loads.

Short-term in vitro effects of low frequency ultrasound on odontoblast-like cells.

In this study, the effects of low frequency ultrasound (US) were examined on odontoblasts, the primary cell responsible for dentinogenesis and dentine repair. An established odontoblast-like cell line, MDPC-23, was subjected to 30 kHz ultrasound at three different power settings. US induced a marginal level of cell death (3% to 4%) at lower amplitudes rising to 25% cell death at the highest power tested. The latter was reflected in a 30% decrease in cell attachment after 4 to 24 h of culture, while the number of adherent cells was reduced by approximately 10% to 15% in the lower power groups. Cell replication after 24 h, as measured by BrdU incorporation, showed no significant changes in the US-treated groups. Gene expression analyses demonstrated a moderate dose-dependent increase in the expression of GAPDH (glyseraldehyde-3-phosphate dehydrogenase)-normalised collagen type I, osteopontin (OPN), transforming growth factor-beta1 (TGFbeta1) and the heat shock protein (hsp) 70. The greatest change was found in the expression of the small hsp 25/27, which showed a two- to six-fold increase following US treatment. No significant effects were observed for alkaline phosphatase (ALP) and core-binding factor A1 (CBFA1/Runx2) expression levels. This is the first report describing US effects on odontoblasts. Further studies are warranted to elucidate US effects on odontoblast function and to evaluate US as a therapeutic application in dentine repair.