A wide variety of research projects may be considered to be appropriate to general dental practice. In this respect, the volume of clinical material seen in general dental practice makes it an ideal area for the assessment of new techniques and materials. Central to good performance of dental materials are their physical properties and also their ease of use, given that it could be suggested that a restorative which handles easily will be more likely to produce an optimally performing restoration than one which is technique sensitive. The assessment of the handling of a new dental material is therefore important.
The handling of a given material by one operator is necessarily subjective, but when practitioners band together to form a group to assess the handling of new materials in dental practice, the results are likely to be more objective and generalisable. All of this is possible when practitioner-based research groups are teamed with the expertise available in academic institutions.
A UK-based group of practice-based researchers is the PREP (Product Research and Evaluation by Practitioners) panel. This group was established in 1993 with six GDPs, and has grown to contain 30 dental practitioners located across the UK. It has completed over 50 projects, mainly ‘handling’ evaluations of materials and techniques, but also, currently, has six clinical trials of new materials and techniques (varying from two to five years) operating in UK dental practices. One project has involved dentists in mainland Europe (the EuroPREP project).
The product under evaluation in this study is Septodont N’Durance (Septodont, PO Box 253, ME16 0JF. Tel: 01622 695520, emai: information@septodont.co.uk and see also www.septodont.co.uk).
This is a low shrinkage resin composite restorative material which uses novel dimer-acid based resin chemistry1.
Materials and methods
Ten members of the PREP panel were selected at random for participation in this evaluation, two of whom were female. The average time since graduation was 26 years, with a range of 10 to 42 years. Explanatory letters and packs of N’Durance and N’Durance Flow, were distributed to the evaluators in August 2009 with a request that they use the material, where indicated, for 10 weeks. They were also sent a questionnaire (with most responses given on a visual analogue scale), designed to evaluate their current composite usage, and the presentation, instructions, handling, aesthetic quality and post-operative sensitivity of the new composite.
Results
Background information: Seventy per cent (n=7) of the evaluators stated they did not typically use a multi-shade layering technique for anterior composites. Typical comments from the evaluators who did not use a layering technique routinely were:
- ‘Usually two shades sufficient’
- ‘Only use multi-shade layering for large anterior restorations’ and
- ‘Simplicity – current composite very forgiving’
Ninety per cent (n=9) of the evaluators stated that they normally placed composite restorations in posterior teeth. When asked about the technique used for posterior composite restorations, 90 per cent used a dentine bonding agent, with 30 per cent using a glass ionomer base/sandwich and 70 per cent a flowable composite base layer.
A wide range of composite materials were used prior to this study by the respondents with three of the respondents using more than one material. The principal reasons for the choice of these materials were good aesthetics, ease of use, good results, ease of finishing, consistency, familiarity and, for posterior teeth, low shrinkage.
When the evaluators were asked to rate the ease of use of their current anterior composite material, the result was as follows:
Difficult to use Easy to use
1 5
4.5
When the evaluators were asked to rate the ease of use of their current posterior composite material, the result was as follows:
Difficult to use Easy to use
1 5
4.3
The evaluators currently used a variety of dentine/bonding systems. Nine (90 per cent) of the evaluators expressed a preference for composite materials to be supplied in Vita (Vita Zahnfabrik, Germany) shades, though one evaluator commented ‘I have got used to the Miris system which doesn’t use Vita shades’.
The aesthetic quality of anterior restorations placed by the evaluators using their current composite material was rated as follows:
Poor Excellent
1 5
4.5
Evaluation of Septodont N’Durance
The total number of restorations placed during the evaluation was 583, comprised of 293 anterior and 290 posterior restorations.
Evaluators rated the presentation of the kit as follows:
Poor Excellent
1 5
4.0
The ease of use of the shade guide was rated as follows:
Poor Excellent
1 5
3.9
When the evaluators were asked to give their, and their nurse’s, assessment of the dispensing and placement of N’Durance the result was as follows:
Inconvenient Convenient
1 5
4.5
When the evaluators were asked if the material flowed satisfactorily when a matrix was applied, the result was as follows:
No Yes
1 5
4.3
The viscosity of the material was rated as satisfactory by nine (90 per cent) of the evaluators. The remaining evaluator stated it was too viscous.
Six of the evaluators (60 per cent) stated that the material had sufficient working time but five evaluators (50 per cent) commented that some shades set prematurely under ambient or operating light. ‘More of a nuisance than a problem’ one evaluator commented.
All (100 per cent) of the evaluators stated that the restorations were easily finished and polished using their normal systems and that the restoration margins were visually satisfactory.
When the evaluators were asked to assess translucency/opacity of N’Durance, the result was as follows:
Too opaque Too translucent
1 5
3.5
The overall aesthetic quality of restorations placed by the evaluators using N’Durance was rated as follows:
Poor Excellent
1 5
4.2
Ninety per cent (n=9) of the evaluators stated that sufficient shades of N’Durance were provided. No post-operative sensitivity was reported by any of the evaluators.
The principal use of N’Durance was seen by the evaluators as follows: anterior - two evaluators, posterior - two evaluators and universal - six evaluators.
Eight (80 per cent) of the evaluators stated that, overall, N’Durance was satisfactory and the same number would both purchase the material and also recommend it to colleagues.
The evaluators rated the ease of use of N’Durance as follows:
1. Anterior
Difficult to use Easy to use
1 5
4.1
2. Posterior
Difficult to use Easy to use
1 5
4.3
Final comments made included:
- ‘Too stiff for anterior use – nice for posteriors and polished well,’ ‘Liked the compule colours and sealing caps were user friendly,’ ‘A real surprise – a nice one at that! I have bought more!’
- ‘Need to sort early polymerisation of some shades’ (three evaluators),
- ‘My nurse suggested that the shade be put on the other end of the compule so that it’s not hidden by the holder’ ‘Material shade changed on curing – took on tooth colour – good chameleon effect,’ ‘Septodont on to a winner – get the working time right on some shades though,’ ‘I really liked this material for posterior and anterior use.’
Discussion
The Septodont N’Durance Universal Composite system has been subjected to an extensive evaluation in clinical practice by members of the PREP panel in which 583 restorations were placed. Based on this, the following conclusions may be made:
- The presentation of the kit scored well (all scores 4.0 or above on a Visual Analogue Scale [VAS] where 5 = excellent and 1 = poor) in all criteria related to presentation, but two evaluators would have liked the printing to have a larger font to make shade selection easier.
- Most evaluators did not typically use a multi-shade layered composite technique for the placement of anterior composite restorations. Ninety per cent (n=9) of the evaluators stated that there were sufficient shades of N’Durance provided. The rating for translucency/opacity of 3.5 (on a VAS where 5 = too translucent and 1 = too opaque) assessed for N’Durance is close to the ideal median score. The overall score for aesthetic quality of 4.2 (on a VAS where 5 = excellent and 1 = poor) compares well with the scores of 4.5 for the pre-trial material.
- The new material scored the same for ease of use compared with the GDPs’ current posterior system (4.3 v 4.3 on a VAS where 1 = difficult to use and 5 = easy to use) and similar for anterior use (4.1 v 4.5 on the same VAS). However, 50 per cent (n=5) of the evaluators commented that some shades (especially the lighter ones) set prematurely under ambient or the operating light.
Conclusion
Overall the good reception of this new material has been underlined by the 80 per cent (n=8) of evaluators who stated they would both purchase the system and recommend it to colleagues.
N’Durance Dimer Flow evaluation
All the evaluators (100 per cent) stated they had previously used a flowable composite restorative material. The proportion, by usage, was as follows: Class V 25 per cent, base under composite 53 per cent, and ‘other’ 22 per cent. A variety of flowable materials were previously used, with the principal reasons being good results, familiarity and cost.
The evaluators rated the ease of use of their current flowable composite as follows:
Difficult to use Easy to use
1 5
4.5
The overall aesthetic quality of the current flowable composite restorations were rated as follows:
Poor Excellent
1 5
4.3
The total number of restorations placed during the evaluation was 219, comprised of 41 anterior, and 178 posterior restorations.
When the evaluators were asked to give their, and their nurse’s, assessment of the dispensing and placement of N’Durance Flow the result was as follows:
Inconvenient Convenient
1 5
4.0
All the evaluators stated that the syringes worked satisfactorily and also that the tip was a satisfactory size. Regarding the viscosity of the material, two evaluators (20 per cent) felt it was too viscous. One evaluator commented that it ‘Occasionally clumped and did not flow’. Ninety per cent (n=9) of the evaluators stated that the material had sufficient working time. One evaluator commented that occasionally ambient light set the material but that this was not such a problem as the material can be placed quickly. All the evaluators stated that the restorations of N’Durance Flow were easily polished.
The overall aesthetic quality of the N’Durance Flow composite restorations were rated as follows:
Poor Excellent
1 5
4.5
The number of shades of N’Durance Dimer Flow required was stated to be on average three (range two to four).
Ninety per cent (n=9) of the evaluators stated that they were satisfied with the material, and 80 per cent (n=8) would purchase N’Durance Flow if available at average cost and also the same percentage would recommend the material to colleagues.
When the evaluators were asked if they considered any changes necessary for the acceptability of N’Durance Flow, the following comments were made: ‘Make flow more evenly’ (two similar), ‘Place in capsules rather than syringes – helps cross-infection control’.
The evaluators rated the ease of use of N’Durance Flow as follows:
Difficult to use Easy to use
1 5
4.0
Final comments made included: ‘I liked the composite but would like more flow from the flowable’ (two similar), ‘Black plastic tips – like Ultradent – make placement easier’.
Discussion
The Septodont N’Durance Dimer Flow system has been subjected to an extensive evaluation in clinical practice by members of the PREP panel in which 219 restorations were placed. The overall score for aesthetic quality of 4.5 (on a VAS where 5 = excellent and 1 = poor) was a slight improvement on the score of 4.3 for the pre-trial material. The new material achieved a similar score for ease of use compared with the GDPs’ current flowable system (4.0 v 4.5 on a VAS where 1 = difficult to use and 5 = easy to use).
Conclusion
Overall the good reception of this new material has again been underlined by the 80 per cent (n=8) of evaluators who stated they would both purchase the system and recommend it to colleagues.
Reference
1.Bracho-Troconis C, Rudolph S, Boulden J, Wong N et al. Characterisation of a new dimmer acid resin nano-hybrid composite. J Dent Res. Spec.Issue. 2008: 86: Abstract 81.
Manufacturer's comments
Septodont would like to thank all members of the PREP Panel for their time and efforts in running this extensive evaluation.
The fact that 80 per cent of the evaluators would both purchase and recommend N'Durance and N'Durance Dimer Flow confirms that Septodont developed the right technology to enter the composite world: Nano-Dimer Conversion Technology. This technology offers clinicians both a low-shrink and low-stress composite, along with high conversion values improving on the mechanical properties, polishability of the product and absence of post-operative sensitivity. Septodont's objective with Nano-Dimer Conversion Technology is to make innovation in composite resin affordable to enhance everyday dentistry and give excellent value for money. Septodont is convinced that N'Durance and N'Durance Dimer Flow will contribute to the goal of clinicians to practise better dentistry without compromise.
The members' remarks show that there is still room for improvement and our R&D teams are working on it, namely to correct the sensitivity to ambient light and to improve on the translucency. No doubt we will ask the PREP Panel to evaluate our further product developments.