Biomedical subjects

M Sherriff

Publications and source records attributed to M Sherriff.

At least 19 recordsLinked to original sources

PubMed2007

The penetration of RealSeal primer and Tubliseal into root canal dentinal tubules: a confocal microscopic study.

AIM: To compare penetration depth into dentinal tubules of RealSeal with that of a well-established endodontic sealer (Tubliseal) by means of confocal microscopy. METHODOLOGY: Twenty sound extracted, single-rooted premolars were selected. Following completion of root canal instrumentation, the teeth were divided into two groups using a stratified sampling method, ranking teeth according to size. In group 1, 10 teeth were filled with Gutta-percha and Tubliseal using cold lateral condensation. In group 2, 10 teeth were filled with RealSeal. Both sealers were labelled with Rhodamine B dye. The teeth were sectioned parallel to their long axis resulting in 20 specimens per group. Confocal microscopy was used to assess the penetration depths of the sealers at three sites for each specimen (coronal, middle and apical). Data were analysed statistically using Stata Release 9.1. RESULTS: The penetration depth of RealSeal in each one of the thirds of the root canal was found to be higher than that of Tubliseal (P < 0.05). The penetration depths of the two sealers was found to be significantly different (P = 0.001). The mean penetration value for the RealSeal group was 908.8 microm whereas the mean value for the Tubliseal group was 139.5 microm. CONCLUSIONS: The penetration depth of RealSeal into the root dentinal tubules is significantly greater than that of Tubliseal.

Bicuspid↗

PubMed2006

The effect of temperature on viscosity of root canal sealers.

AIM: To test the hypothesis that there was no significant (alpha = 0.05) change in viscosity of commercially available root canal sealers with increase in temperature using a high-performance Advanced Rheometric Expansion System (ARES) rheometer. METHODOLOGY: Materials tested were Apexit, Tubliseal EWT, Grossman's, AH Plus and Ketac-endo. Cone-and-plate geometry was used (25-mm diameter, 0.1 radian and gap 0.051 mm). Measurements were carried out for steady-state viscosity at 25 and 37 degrees C in the shear rate range of 0.001-50 s(-1) at standardized relative humidity and within 30 min from the start of mixing. Five samples were taken for each sealer at each temperature. RESULTS: At 25 degrees C all sealers demonstrated shear thinning. At 37 degrees C Grossman's (powder : liquid ratio 2 : 1 and 3 : 1) and Ketac-endo had a rapid rise in viscosity and early set whereas the other sealers were shear thinning. On increasing temperature from 25 degrees C to 37 degrees C, Apexit, Tubliseal and AH Plus had reduced viscosity whereas Grossman's 2 : 1, Grossman's 3 : 1 and Ketac-endo had increased viscosity, which varied with the shear rate. The change in viscosity with change in temperature was significant (P < 0.05) for all sealers except AH Plus. CONCLUSIONS: There was a variation in the effect of increasing temperature on each sealer depending on the shear rate. With the exception of AH Plus, a significant (P < 0.05) change in viscosity was found, and the null hypothesis was rejected.

Calcium Hydroxide↗

PubMed2006

Hand and nickel-titanium root canal instrumentation performed by dental students: a micro-computed tomographic study.

The aim of this study was to evaluate root canals instrumented by dental students using the modified double-flared technique, nickel-titanium (NiTi) rotary System GT files and NiTi rotary ProTaper files by micro-computed tomography (MCT). A total of 36 root canals from 18 mesial roots of mandibular molar teeth were prepared; 12 canals were prepared with the modified double-flared technique, using K-flexofiles and Gates-Glidden burs; 12 canals were prepared using System GT and 12 using ProTaper rotary files. Each root was scanned using MCT preoperatively and postoperatively. At the coronal and mid-root sections, System GT and ProTaper files produced significantly less enlarged canal cross-sectional area, volume and perimeter than the modified double-flared technique (P < 0.05). In the mid-root sections there was significantly less thinning of the root structure towards the furcation with System GT and ProTaper (P < 0.05). The rotary techniques were both three times faster than the modified double-flared technique (P < 0.05). Qualitative evaluation of the preparations showed that both ProTaper and System GT were able to prepare root canals with little or no procedural error compared with the modified double-flared technique. Under the conditions of this study, inexperienced dental students were able to prepare curved root canals with rotary files with greater preservation of tooth structure, low risk of procedural errors and much quicker than with hand instruments.

Dental Alloys↗

PubMed2006

An investigation into the use of a single component self-etching primer adhesive system for orthodontic bonding: a randomized controlled clinical trial.

OBJECTIVE: This study assessed the in vivo bond failure of the single component orthodontic self-etching primer system, Ideal 1 (GAC Orthodontic Products) and compared it with the conventional acid etching using a conventional 37% o-phosphoric acid, rinsing and drying regimen when bonding stainless steel orthodontic brackets to enamel. DESIGN: Prospective randomized, controlled clinical trial. SETTING: Orthodontic Department, Bristol Dental School. MATERIAL AND METHODS: Twenty consecutive patients undergoing upper and lower fixed orthodontic treatment entered this cross-mouth control study. Diagonally opposite quadrants were randomly allocated to either the self-etching primer group or the conventional etching group. A total of 339 teeth were bonded with Ideal 1 light-cured adhesive. Bond failures and locus of bond failure were then recorded at 1, 6 and 12 months. RESULTS: Significantly more bond failures occurred at each of the 3 time intervals, 1, 6 and 12 months, where the enamel was pretreated with the Ideal I self-etching primer, than when the enamel was treated with the conventional etchant, 37% o-phosphoric acid. With the latter the cumulative bond failure rates were 3.0, 5.3 and 14.8%, respectively. With the self-etching primer the cumulative failure rates were 29.4, 56.5 and 72.4%. CONCLUSION: The study found that enamel pre-treatment with the Ideal 1 self-etching primer system prior to orthodontic bonding results in an unacceptably high bond failure rate when compared with conventional enamel acid etching.

Acid Etching, Dental↗

PubMed2006

An in-vitro investigation into the use of a single component self-etching primer adhesive system for orthodontic bonding: a pilot study.

OBJECTIVE: This pilot study assessed force to debond (N); time, and site of bond failure of a single component self-etching primer (SEP) and adhesive system, Ideal 1 (GAC International Inc., USA) and compared it with the conventional acid etch and rinse regimen using 37% o-phosphoric acid solution and either Transbond XT (3M Unitek) or Ideal 1 adhesive. DESIGN: In vitro laboratory study. SETTING: Bristol Dental Hospital, UK. Sept 2003-Sept 2004. MATERIAL AND METHODS: Nine groups of 20 premolars were bonded using metal orthodontic brackets using three protocols: (1) 37% o-phosphoric acid etch and Transbond XT adhesive; (2) 37% o-phosphoric acid and Ideal 1 adhesive; (3) Ideal 1 SEP and Ideal 1 adhesive. Force to debond and locus of bond failure were determined at three time intervals. RESULTS: Enamel pre-treatment prior to bonding, namely SEP versus conventional etching had no significant effect on the median force to debond with the Ideal 1 adhesive. Similarly, when the enamel was conventionally etched, the adhesive type, namely Ideal 1 or Transbond XT, had no significant effect on the measured force to debond. However, there appeared to be differences in the locus of bond failure: failure predominated at the enamel/adhesive interface for the Transbond XT conventional etch group and at adhesive/bracket interface for the Ideal 1 SEP and adhesive group and the Ideal 1 adhesive conventional etch group. CONCLUSION: These results suggested that the complete Ideal 1 SEP and adhesive system might be successful in vivo leading therefore to a clinical trial. However, implications for clean up time are discussed and improvements to in vitro study designs are advised.

Acid Etching, Dental↗

PubMed2005

The survival of resin modified glass ionomer and stainless steel crown restorations in primary molars, placed in a specialist paediatric dental practice.

AIMS: To prospectively report on the survival of resin-modified glass ionomer cement (RMGIC), photac-fil and pre-formed stainless steel crown (SSC) restorations in primary molar teeth placed over a seven-year period in a specialist paediatric dental practice under private contract of remuneration. METHOD: All primary molar restorations placed by a specialist paediatric dentist over a seven-year period were reviewed and the outcome results recorded. Data were recorded at review visits until June 30, 2003. Data recorded included Class I restorations, Class II restorations and SSC. The Class II cavities were either mesial or distal, with or without buccal/palatal extensions. If both proximal surfaces were decayed or if after cavity preparation the resultant outline form was significantly larger than the minimal classical form, RMGIC was not used; an SSC was placed instead. Stainless steel crown preparation followed conventional guidelines. The crowns were cemented with reinforced zinc oxide and eugenol (Kalzinol). The status was recorded as satisfactory restoration, tooth exfoliated, tooth extracted for orthodontic reasons with the date of extraction, or needing replacement. If replaced then the reason for replacement was also recorded. RESULTS: A total of 544 Class I RMGICs, 962 Class II RMGICs, and 1,010 SSCs were placed. At the last review of each restoration, 98.3% of Class I, 97.3% of Class II RMGICs and 97.0% of SSCs were either satisfactory or withdrawn intact. CONCLUSION: Under the conditions of private specialist practice-based study SSCs continued to prove very successful for the restoration of larger cavities and for pulp-treated primary molar teeth. For the smaller cavities RMGIC were also very successful.

Adolescent↗

PubMed2005

Delay in diagnosis and its effect on outcome in head and neck cancer.

We examined the records of two cohorts of patients who were seen from 1960 to 1999 with a diagnosis of squamous cell carcinoma (SCC) of the mouth and throat, one series being retrospective (n=400) and the other prospective (n=213) to find out about delays in diagnosis. The median delay in both cohorts was 3 months and the patients were responsible for the delay in most cases (n=319, 81% and n=160, 78%, respectively). Half the patients in each cohort had delayed diagnoses (n=217, 54% and n=119, 56%, respectively) and similar percentages (n=110, 53% and n=172, 47%) presented with advanced disease (stage III or IV). These were not the same patients for there was no correlation between delay and stage or survival. Logistic regression analysis showed that non-white race (p=0.01) and high-grade histology (p=0.002) predicted advanced disease. The proportion of patients presenting with advanced disease had not changed in 40 years despite public education. We suggest that some tumours may be silent and that initial symptoms do not reliably predict early disease.

Adolescent↗

PubMed2005

Dolphin Imaging Software: an analysis of the accuracy of cephalometric digitization and orthognathic prediction.

The purpose of this study was to examine and compare the reproducibility and reliability of digitization using Dolphin Imaging Software (Version 8.0) with traditional manual techniques. In addition, orthognathic prediction was compared with actual outcomes. Sixty lateral cephalograms were evaluated by two methods: manual tracing and indirect digitization using Dolphin Imaging Software (Version 8.0). Method error (reliability) using duplicate measurements for each method, and comparison of both techniques (reproducibility), were investigated using alternative statistical methods, Bland and Altman (1986) and Lin's Correlation of Concordance (1989). Each technique was significantly reliable at the 95% level (method error). Comparing the standard deviations of the differences, manual tracing proving more reliable for SNA (1.36 degrees manually, 2.07 degrees digitally), SNB (1.19 degrees and 1.69 degrees ), SNMx (1.39 degrees and 2.66 degrees ), and MxMd (1.77 degrees and 2.26 degrees ), and Dolphin digital tracing more reliable for UIMx (3.49 degrees digitally and 3.97 degrees manually) and LIMd (2.90 degrees and 3.04 degrees ). However, systematic error in the software's calculation of LAFH% resulted in measurements 4% larger than manual techniques, a difference which is clinically significant. Comparison of actual outcome and software generated prediction for 26 orthognathic cases demonstrated clinically significant differences for all measurements (rhoc 0.32 for ANB to 0.91 for LIMd; P<0.05). The investigation revealed the impact of radiographic magnification when used in an uncalibrated system. These findings indicate that Version 8.0 of Dolphin Imaging Software needs to be re-assessed for software errors that may result in clinically significant miscalculations, and to facilitate compensation of radiographic magnification when using linear measurements.

Cephalometry↗

PubMed2005

Heterogeneity, histological features and DNA ploidy in oral carcinoma by image-based analysis.

Oral squamous carcinomas appear heterogeneous on DNA ploidy analysis. However, this may be partly a result of sample dilution or the detection limit of techniques. The aim of this study was to determine whether oral squamous carcinomas are heterogeneous for ploidy status using image-based ploidy analysis and to determine whether ploidy status correlates with histological parameters. Multiple samples from 42 oral squamous carcinomas were analysed for DNA ploidy using an image-based system and scored for histological parameters. 22 were uniformly aneuploid, 1 uniformly tetraploid and 3 uniformly diploid. 16 appeared heterogeneous but only 8 appeared to be genuinely heterogeneous when minor ploidy histogram peaks were taken into account. Ploidy was closely related to nuclear pleomorphism but not differentiation. Sample variation, detection limits and diagnostic criteria account for much of the ploidy heterogeneity observed. Confident diagnosis of diploid status in an oral squamous cell carcinoma requires a minimum of 5 samples.

Carcinoma, Squamous Cell↗

PubMed2005

An investigation into the use of two polyacid-modified composite resins (compomers) and a resin-modified glass poly(alkenoate) cement used to retain orthodontic bands.

The aim of this investigation was to determine the effectiveness of a conventional glass poly(alkenoate) cement (Intact) and newer polyacid-modified composite resin cements (Transbond Plus and Ultra Band-Lok) to retain orthodontic bands. In the in vitro part of this study, stainless steel bands were cemented to 240 extracted third molar teeth in three test groups comprising Intact, Transbond Plus and Ultra Band-Lok. The force to deband (N) for all three cements was recorded using an Instron universal testing machine after the following observation periods: 20 minutes and 3, 6 and 12 months. The results indicated that all three cements increased their median force to deband after 12 months. Of the two compomers, Transbondtrade mark Plus demonstrated the highest median force to deband at all four time intervals. In the in vivo part of the study, 30 patients participated in a randomized cross-mouth clinical trial where the molar bands were cemented in place using either Intact or Transbond Plus. Ultra Band-Lok was not used in the clinical part of the study. The results showed there to be no clinically significant difference in band failure rates between the two cements. When patients were asked to score each for taste, there was a significant difference, with the glass poly(alkenoate) cement (Intact) being more acceptable than the polyacid-modified composite Transbond Plus (P < 0.001). No significant differences were observed in the in vitro median force to deband or in vivo band failure rates between the glass poly(alkenoate) cement and the polyacid-modified composite resins. The choice of cementing agent can therefore be made on patient factors, e.g. taste, or operator factors, e.g. ease of handling, cost and shelf life.

Cementation↗

PubMed2005

Enamel loss at bond-up, debond and clean-up following the use of a conventional light-cured composite and a resin-modified glass polyalkenoate cement.

The aim of this study was to determine whether there was any difference in the degree of enamel loss at bond-up, debond and enamel clean-up when two different adhesive systems were tested and with four different methods of enamel clean-up. The adhesive systems were 37 per cent o-phosphoric acid with Transbond XT (group 1) and 10 per cent poly(acrylic acid) conditioner with Fuji Ortho LC (group 2). Using flattened enamel specimens, enamel loss at each stage was determined using a planer surfometer. These stages were: prior to treatment, at pumice prophylaxis, following enamel etching or conditioning and following enamel clean-up. The four clean-up methods were a high-speed tungsten carbide bur, a slow-speed tungsten carbide bur, an ultrasonic scaler and debanding pliers. The results, analysed using non-parametric tests, demonstrated that significantly more enamel loss occurred following the use of 37 per cent o-phosphoric acid than poly(acrylic acid) conditioner (P = 0.001). At debond and prior to clean-up, more adhesive remained on the enamel surface in group 1 than in group 2 (P = 0.005). During the subsequent enamel clean-up and with both adhesive systems, the least enamel loss occurred following the use of the slow-speed tungsten carbide bur and the greatest loss was seen with the ultrasonic scaler or high-speed tungsten carbide bur.Overall, the lowest enamel loss was observed with the poly(acrylic acid) conditioner and Fuji Ortho LC system (group 2) and where enamel clean-up was performed using the slow-speed tungsten carbide bur.

Acrylic Resins↗

PubMed2005

Penetration of bonding resins into fibre-reinforced composite posts: a confocal microscopic study.

AIM: To compare the penetration of two different bonding resins applied for different contact times, on glass reinforced-reinforced composite root canal posts showing an interpenetrating polymer network (IPN) or cross-linked polymer matrix. The research hypothesis was that the bonding resins were equally able to penetrate into the IPN post whereas less penetration was evident into the cross-linked post. In addition, the prolonged contact time of the bonding resin on the surface of post was assumed to increase the resin penetration. METHODOLOGY: A total of 36 posts, comprising 18 IPN posts (everStick Post) and 18 cross-linked posts (C Post Millennium) were divided into 12 groups of three posts. All posts had a diameter of 1.2 mm. Both bonding resins (Scotchbond Multi Purpose Plus and Stick Resin) were labelled with Rhodamine B for determination of the resin penetration into the post. After contact times of 1, 30 and 300 s the bonding resins were light cured for 60 s. Penetration of bonding resins into three sections of each post was measured by confocal scanning light microscope. The influences of post and type of adhesive resin on resin diffusion into the polymer matrix of the post were assessed by nonparametric methods. RESULTS: For C Post Millennium and for 1 s contact time, no penetration of bonding resins into the polymer matrix of posts occurred in any section of any post. For the everStick Post, penetration was always noted after 300 s contact (mean 22.8 microm) and nearly always after 30 s contact (mean 3.5 microm), with very little difference between the two adhesives. The degree of penetration into everStick Posts was invariably greater after 300 s contact than after 30 s (P < 0.001). Both sets of results were highly significantly greater than the zero penetration recorded using C Post Millennium or 1 s contact time (P < 0.001). CONCLUSIONS: The ability of bonding resins to penetrate into everStick Post with IPN polymer matrix may give the opportunity to establish a good link between fibre-reinforced composite posts, luting cements and composite cores.

Composite Resins↗

PubMed2005

A study of the rheological properties of endodontic sealers.

AIM: To test the hypothesis that there would be no statistically significant difference in viscosity-related measures of endodontic sealers or change in these with strain rate, internal diameter or powder : liquid ratio in a capillary system. METHODOLOGY: Materials used were Apexit, Tubliseal EWT, Grossman's sealer and Ketac-endo. Viscosity-related measures were tested in a two-plate test, and in a capillary rheometer. The mean values (n = 12) for thickness and diameter of material formed between two glass plates were tested with one-way analysis of variance. Pressure was applied to a capillary rheometer at strain rates 5 and 10 mm min(-1) in tubes of internal diameter 0.6 and 1.2 mm. RESULTS: Tubliseal EWT had a thinner film thickness than the other sealers (alpha = 0.05). The difference in diameter between Tubliseal EWT and the other sealers was significant apart from Apexit. Increased strain rate gave a significant increase (alpha = 0.05) in the flow of all sealers. Narrower tubes produced increased velocity, which was significant for all sealers, and reduced volumetric flow, which was significant for all sealers except Grossman's 2 : 1 (Wilcoxon signed rank test). Reduction in powder : liquid ratio of Grossman's significantly increased flow in narrow tubes and at higher strain rate (Mann-Whitney test). CONCLUSION: There was a significant difference between the flow of Tubliseal EWT and the other sealers tested in the two-plate test; capillary flow was affected by sealer, internal diameter, strain rate and powder : liquid ratio. The null hypotheses were rejected.

Calcium Hydroxide↗

PubMed2005

The isthmuses of the mesial root of mandibular molars: a micro-computed tomographic study.

AIM: To investigate the prevalence of root canal isthmuses in the apical 5 mm of the mesial root of mandibular molars by means of micro-computed tomography (MCT) and to describe the morphology of the isthmuses. METHODOLOGY: Twenty extracted mandibular first molars that had fully formed roots were selected. The mesial roots were sectioned from the distal roots and subjected to MCT. The number of sections showing isthmuses in each of the apical 5 mm of the root canals was recorded. In each one of the apical 5 mm of the 20 roots examined, 40 sections were observed, giving a total of 800 sections observed in each group. Data were analysed as a contingency table using the chi-square statistic to test the null hypothesis that location of the sections in each of the apical 5 mm and presence of the isthmus were independent. RESULTS: Isthmuses were found to be present at all levels with prevalence figures between 17.25 and 50.25%. The chi-square test indicated a significant difference in the distribution of isthmuses with section (P = 0.001). It was found that sections in the first millimetre from the apex had fewer isthmuses than expected and that sections in the third millimetre from the apex had more isthmuses than expected under the null hypothesis. Calcifications were found to be present in most isthmuses, occasionally lateral canals originated from the central part of the isthmuses. CONCLUSIONS: Isthmuses were present in the vast majority of roots observed. The third millimetre from the apex showed more isthmuses than expected. The results of clinical and surgical endodontic procedures performed in the mesial root of mandibular molars may be affected by this aspect of the root canal anatomy.

Dental Pulp Cavity↗

PubMed2005

Microtensile bond strengths to enamel of self-etching and one bottle adhesive systems.

UNLABELLED: This study compared the enamel bond strengths of self-etching and one bottle adhesives, and evaluated microscopically their debonding modes. Evaluated systems were: Self-etch--Prompt L-Pop (LP); one bottle, total etch--Single Bond (SB), Prime & Bond NT (PB); compomer--Hytac Aplitip (HA), F2000 (F2); resin composite- Reference 21 Aplitip (R2), Herculite XRV (XRV), Esthet.X (EX); in the following combinations: LP/HA; LP/R2; SB/F2; SB/XRV; PB/EX. Flat surfaces of enamel were ground on caries free extracted third molars. An adhesive resin was applied to this surface and a restorative material built on it. The teeth were sectioned longitudinally into 1 mm thick specimens and trimmed to a 1 mm2 area at the enamel/adhesive interface. For each material combination, 10 specimens were tested. Microtensile bond strengths were determined at 0.5 mm min(-1). Fractured specimens were examined using confocal and scanning electron microscopy to determine failure modes. Bond strength data was analysed using Kaplan-Meier survival analysis, a log-rank test and a Bonferroni multiple comparison. Failure mode data was analysed with a chi2 test. The interface of additional fluorescent-labelled specimens was examined by laser scanning confocal microscopy. The bond strength data showed significant differences: LP/R2 > LP/HA, SB/F2 and PB/EX; SB/F2 < LP/HA, SB/XRV and PB/EX. Both compomers principally exhibited cohesive failure. Resin composite materials showed more complex failure modes. Fluorescence images demonstrated interfacial characteristics consistent with the failure modes observed. SIGNIFICANCE: bond strength was not influenced by the use of self-etch or one bottle adhesives.

Adhesives↗

PubMed2004

An in vitro investigation of microtensile bond strengths of two dentine adhesives to caries-affected dentine.

OBJECTIVES: To compare the micro-tensile bond strengths of two different adhesive systems (ABF (Clearfil Protect Bond), Kuraray Medical Inc., Tokyo, Japan) and Prime & Bond NT (PBNT, Dentsply, Konstanz, Germany) bonded to caries-affected dentine retained after chemo-mechanical caries removal using Carisolv gel, with that retained after excavation using conventional hand instrumentation. METHOD: Twenty, adult, human extracted carious teeth were used in this split tooth study with bur-cut cavities in sound dentine acting as controls. After clinical caries excavation, the occlusal cavities in each experimental group were restored with either bonding system plus composite. Matchstick-shaped samples through the bond interfaces were sectioned and microtensile bond strengths recorded. Scanning electron microscopy (SEM) was used to ascertain the mode of failure at the restoration-dentine interface. RESULTS: Statistical analysis of the bond strength data showed that for the ABF group, there was no difference in bond strengths between the controls and Carisolv group but these values were significantly higher than those for the hand-excavated samples. PBNT samples showed no significant differences in any of the three test groups, with wider ranging data sets. SEM analysis indicated a variety of failures at the interface including cohesive failures within the caries-affected dentine itself. CONCLUSIONS: From the data generated by this study it could be concluded that microtensile bond strengths of PBNT/composite restorations to caries-affected dentine in clinical cavities were statistically comparable to those to sound dentine. In the ABF/composite restored group (self-etched), the use of conventional hand excavation appeared to weaken the bond strength to the remaining caries-affected dentine. However, the use of Carisolv gel excavation did not compromise bond strengths to caries-affected dentine in either group tested.

Adhesiveness↗

PubMed2004

The national survey of adverse reactions to dental materials in the UK: a preliminary study by the UK Adverse Reactions Reporting Project.

OBJECTIVE: Dental treatment involves the use of a wide range of materials. Many of the dental materials or their components pose a potential risk to the patient and member of the dental team. Pre-market biocompatibility testing cannot guarantee absolute safety, making monitoring of materials likely to cause an adverse reaction essential. The prevalence of adverse reactions to dental materials amongst dental patients and staff has not been systematically monitored in the UK. This project aims to develop a systematic approach to the evaluation and monitoring of the extent and severity of adverse reactions to dental materials in the UK. METHOD: Through the distribution of reporting forms to dental surgeries and laboratories in the UK, the ARRP has received 1,075 complete reports relating to adverse reactions seen or experienced by dental staff and patients. RESULTS: The main findings were that different materials cause adverse reactions to different groups of people. The largest proportion of patient related adverse reactions were reported to be due to metals (n = 175). These were mainly amalgam associated oral lichenoid reactions (n = 124). Dental technicians reported acrylic resin as the causal factor of hand dermatitis in 61% (44 out of a total 72) of cases reported. Finally, dental surgery staff reported gloves as causing hand dermatitis in 75% of cases (398 out of a total 531). CONCLUSIONS: Different dental materials affect different person groups depending on their exposure to the material. Dental staff are most at risk from an adverse reaction to latex gloves, whereas most reported reactions for patients were due to metals. For dental technicians the biggest danger of an adverse reaction was from acrylic resins. There is a need to continue to raise the awareness among dental professionals of the existence of the Adverse Reactions Reporting Project so as to overcome problems of under-reporting.

Acrylic Resins↗

PubMed2004

The surface effects of erosion and abrasion on dentine with and without a protective layer.

OBJECTIVE: The aim of this in situ study was to investigate with four imaging modalities whether covering dentine with adhesive resins could protect against erosion from acids. The objectives were to observe and quantify the effects of acids and the soft tissues, especially the tongue, on dentine and the bonding agents using four assessment techniques: qualitative assessment with SEM, surface roughness and thickness of resin with the TSM and volume loss with the laser profilometer. DESIGN: An in situ investigation using extracted dentine sections embedded in splints held on the palate of 10 volunteers. The dentine sections were protected by two resins and subjected to a tooth wear regime. RESULTS: Both Seal and Protect and Opitbond Solo protected the tooth surfaces from a tooth wear regime. There were no statistical differences between the control surfaces and those protected with dentine bonding agents for resin thickness, roughness and profilometry. The appearance of the slabs under both confocal and SEM showed that the material remained in place despite a vigorous wear regime and therefore protected the tooth surface. CONCLUSIONS: For patients with uncontrolled erosion or tooth wear, applying a dentine bonding agent to exposed dentine is a practical option to prevent further damage.

Adult↗