SmartPoint: dramatically reducing the failure rate of root canal treatments in orthodontistry
Submitting InstitutionUniversity of Bradford
Unit of AssessmentAeronautical, Mechanical, Chemical and Manufacturing Engineering
Summary Impact TypeHealth
Research Subject Area(s)
Engineering: Manufacturing Engineering, Materials Engineering, Interdisciplinary Engineering
Summary of the impact
A manufacturing process developed by Bradford researchers has
revolutionised the way endodontists perform root canal treatments. When
coated with a hydrophilic polymer, the highly-filled hygroscopic material
has enabled UK company DRFP to develop SmartPoint — a new
endodontic technique that dramatically reduces failure rates of root canal
treatments from 11-30% over five years to approximately 1%, and gives
lower levels of post-operative pain when compared with conventional
techniques. The technology has won three awards for innovation and DRFP
has expanded significantly, with a dedicated production facility and sales
team offering visits to dentists to demonstrate the benefits of the
The Bradford Centre for Polymer Micro and Nano Technology (MNT) is
internationally recognised for its expertise in micro scale moulding
processes (1,2,3) which has grown from pioneering initial studies which
commenced in 2001 when dedicated micromoulding technologies began to
transfer from lab scale developments to full industrial hardware
solutions. Under the Directorship of Phil Coates (Professor 1993-present)
researchers involved included Dr Ben Whiteside (PDRA 2001-2006, Lecturer
2006-present), Keith Norris (Experimental Officer 2008-present), Dr Majiid
Actar (PDRA 2008-2009), Andrew Czencusz (Process Technician 2008-2010) and
John Wyborn (Process Technician 2009-present).
In 2006, researchers the Centre were approached by UK company DRFP Ltd.
to help it develop a new market for its hydrophilic polymer technology.
The company realised its hydrophilic polymer could be used to seal
irregular shaped spaces, such as root canals in endodontistry, but was
struggling to find a partner who could make the necessary core material to
enable this application. The Centre was able to offer the company
significant expertise in material selection and compounding, ultra high
precision moulding, in-line process monitoring (4) and high-resolution
product characterisation (5), which was required to satisfy the needs of
In order to fit the requirements for endodontistry, the core material
needed to be flexible enough to fit random shapes of root canals but stiff
enough to insert. It also needed to be compatible with DRFP's hydrophilic
polymer, enabling it adhere to the core and to swell only in the radial
direction. Two further challenging requirements were that the core had to
be radio-opaque (visible on x-rays) and compatible with a
mass-manufacturing technique such as micro-injection moulding. These two
requirements were particularly challenging, as a highly filled,
radio-opaque, material is very difficult to mould in the high aspect
ratios required for this application.
A multi-component polymer matrix and micro-powder filler material needed
to be accurately blended to provide good consistency and the correct
degree of radiopacity. Key parameters included polymer ratios and filler
particle size. Materials were assessed based on their flow behaviour,
mechanical properties and radiopacity (assessed using x-ray). The use of
such heavily filled (60% ZrO2 by weight) hygroscopic materials
then required careful material preparation and handling prior to, and
during, the micromoulding process as a moisture content outside a very
small range would result in brittle, or incomplete components.
Rheological assessment of the candidate materials was the key to moulding
success and previous pioneering research work (6) investigating flow
behaviour at very high shear rates (characteristic of this type of
geometry) allowed the materials to be tested in environments which were
outside the scope of standard testing methods. In addition, these tests
showed significant differences between the anticipated and actual flow
behaviour, which were used to modify the production process in order to
achieve a high quality product.
To achieve the required feature sizes and tolerances, specialized
manufacturing techniques were needed to produce the cavity forms for the
micromoulding process. Microsystems UK (www.microsystems.uk.com) were
selected from the extensive network of companies known to Polymer MNT as
the provider of the mould cavities. Off-line surface characterisation
techniques were used to verify cavity forms prior to the moulding process.
The product form required the accurate high-pressure and high-speed
injection rates offered by one of the Microsystem 50 micromoulding
machines available at the Centre which was specifically designed for
moulding abrasive materials such as the ZrO2 composite used in
this research. State-of-the-art data acquisition techniques combined with
the expertise of the staff within the Centre developed during previous
research activities ensured that the optimised process window could be
identified and the high aspect ratio cavity was completely filled in a
repeatable manner, a feat which previously had been impossible during
trials at leading commercial injection moulders.
Once the products had been verified in use over a range of clinical
trials, the University worked to develop a production process capable of
meeting the required demand for products which involved the design and
manufacture of a completely new tooling solution capable of making parts
in a fully automated system within an ISO Class 7 clean room environment.
With the new system, production rates are typically 3000 components per
References to the research
1. Whiteside BR, Martyn MT, Coates PD, Greenway G, Allen P, Hornsby P.
(2003) Micromoulding: process characteristics and product properties. Plastics,
Rubber and Composites 32(6): 231-239.
2. Whiteside BR, Martyn MT, Coates PD, Greenway G, Allan PS, Hornsby PR.
(2004) Micromoulding: process measurements, product morphology and
properties. Plastics, Rubber and Composites: Macromolecular
Engineering 33(1): 11-17.
3. Whiteside BR, Martyn MT, Coates PD. (2006) Introduction to
Micromoulding, in Greener J and Wimberger-Friedl R (eds) Precision
Injection Moulding. Munich:Carl Hanser Verlag: 239-264.
4. Whiteside BR, Martyn MT, Coates PD. (2005) In-process monitoring of
micromoulding-assessment of process variation. International Polymer
Processing 20(2): 162-169.
5. Whiteside BR, Spares R, Coates PD. (2006) In-process 3D assessment of
micromoulding features, in Gorecki C, Asundi AK, Osten W. (eds.) Proceedings
of SPIE 6188, Optical Micro-and Nanometrology in Microsystems Technology.
6. Kelly AL, Gough T, Whiteside BR, Coates PD. (2009) High shear strain
rate rheometry of polymer melts. Journal of Applied Polymer Science
(2), (5), and (6) are the three references best indicating the quality of
The quality of the research is evidenced by the following peer-reviewed
and competitive awards: EPSRC, 2001-2003, Micromoulding £229,000,
Yorkshire Forward/ERDF, 2005-2008, Nanofactory, £872,000, Contract
No. 901117; PI Coates.
DTI, 2006-2009, £753,000, Project No.CHBS/007/00050C, PI Coates.
FP7, 2008-2012, COTECH, £330,000, PI Coates.
ERDF, 2009-2013, Nanofactory, £1,124,000 Contact No. 903771. PI
Details of the impact
The filled polymeric material manufacturing process developed at Bradford
has enabled the introduction of a product that has revolutionised the way
root canal treatments are performed (a). The manufacturing techniques
pioneered at Bradford are today used to manufacture more than 150,000
points annually using the moulding facilities at the University and the
production facility in Sheffield. These are used by orthodontists in the
UK and the Netherlands and have received excellent feedback (see
testimonials on DRFP's website) (b). The technology has also gained FDA
approval in the US. This collaborative research work enabled DRFP to
launch its product in 2007 and the company has since grown from three
people in 2006 to 12 employees in 2013 based at a dedicated manufacturing
facility in Sheffield where the points are coated, packaged and shipped to
distributers in the UK, Holland and the USA (c).
There are several reasons why this product has proved so popular: it is
much simpler to use than conventional techniques; gives quick,
long-lasting results; and gives a better outcome for the patients. In 2007
a three-year clinical trial with annual check-ups for patients was started
using SmartPoint. Informal feedback based on cases that have been
monitored for in excess of three years has indicated the clinical results
are good with good healing and no complications (c). A user panel of
approximately 20 dentists has been set up to provide feedback on DRFP
products. To date, there have been over 1,200 cases documented with 14
failures (retreatment required). This failure rate of approximately 1%
compares favourably with typical retreatment/failure rates taken from the
literature of 11-30% for endodontic procedures over a 5 year period. The
wide variation in the figures can be attributed to the broad range of
studies which consider a variety of problems to be treated and conditions
of the tooth. Informal feedback from various sources (customers, user
panel members, and the clinical trial) (d,e) indicates that patients
report low levels of post-operative pain, which was attributed to a less
"aggressive" procedure and the good healing attributes of the product. No
force is required to compact the obturation point into the prepared canal,
which can cause stress inside the tooth. Research studies completed by
dentists have also validated the functionality (f) and biocompatibility
(g) of the SmartPoint solution. The product now has a history of
use over five years with proven benefits as demonstrated in leading
dentistry journals, and this product is now in increasing demand in a
highly risk-averse marketplace.
There has been an increasing demand for the product from the dental
community in mainland Europe and UK and the product range has expanded
since SmartPoint first hit the market in 2008. The products have
been refined in this period and now include a radio-opaque coating in
addition to the core as a response to the requests of practitioners. The
technology has also won numerous awards (h,i,j).
The collaborative work is now concentrating on process scale-up due to
recent FDA approval opening up the North American marketplace. Critical to
this goal will be a significant increase in core output utilizing
multi-cavity tooling with improved process repeatability and better
product quality with tighter tolerances. The company continues to work
with the University to develop new solutions to the scale up requirement
including automated inspection and handling systems to increase quality
In addition, company employees are working in the University to manage
their own manufacturing process, which is the final stage in the knowledge
transfer process. They can configure, run and troubleshoot the
manufacturing process with minimal support required and implement their
own quality control procedures on site, which has seen significant
improvement in product yield throughout the process chain. This allows
Bradford University staff more time to spend developing new innovations to
improve quality and reduce costs.
In addition, the methods and processes developed during this work have
enabled the Centre for Polymer Micro and Nano Technology at the University
to explore further applications of these technologies and build bespoke
solutions for a range of other companies wishing to develop new
micro-injection moulded products. This work has provided significant value
as a key case study to showcase our ability to deliver research projects
that are near-market and, since this project, we have delivered over 20
new research and development projects with UK-based industrial Partners as
a direct result of the knowledge gained during this process. This work has
enabled the securing of Industrial R&D-focussed, grant-funded
opportunities. Key examples include the ERDF-funded Nanofactory
programme which included Bradford in a consortium of six Yorkshire-based
Universities that has assisted over 100 small and medium enterprises in
the region, and the EU FP7 COTECH programme, which was a highly successful
25-partner programme (of which Bradford was a major RTD contributor) that
saw the creation of three key technology platforms and eight industrial
The underpinning research on polymers and the knowledge base available at
Bradford has been key to developing and manufacturing the SmartPoint
device. This device has brought benefits in terms of improved endodontic
treatments worldwide. This project has also enabled the Centre to build an
effective R&D platform for completion of a range of other programmes
with Industrial partners.
Sources to corroborate the impact
a. Article in Medical Device Technology "Whiteside BR, Manser P (2009)
Micromoulding — the route to a successful product, Medical Device
Technology, 20(2): 18, 20-1. Online version here: http://www.emdt.co.uk/article/micro-moulding-route-successful-product
b. Product website — www.smart-seal.co.uk
c. Operations manager, DRFP Ltd.
d. The Dentist, 26(10): 74, November 2010. Available online at http://www.smart-seal.co.uk/wp-content/uploads/downloads/2013/07/updated-tina-ferguson-case-study.pdf
e. The Dentist, 27(1): 62, January 2011. Available online at http://www.smart-seal.co.uk/wp-content/uploads/downloads/2013/07/the-dentist-JAN-2011006.pdf
f. Eid AA, Nikonov SY, Looney SW, Didato A, Niu L, Levin MD, Reuggebberg
/fa, Pashley DH, Watanabe I, Tay FR. (2013) In vitro
biocompatibility evaluation of a root canal filling material that expands
on water sorption. Journal of Endodontics 39(7): 883-888.
g. Didato A, Ashraf AE, Levin MD, Khan S, Tay FR, Rueggeberg FA. (2013)
Time-based lateral hygroscopic expansion of a water-expandable endodontic
obturation point. Journal of Dentistry 41(9): 796-801.
h. Plastics Industry Awards 2008 Winner — http://www.plasticsawards.com/GJZ97083/2632
i. Medical Design Excellence Award 2011 award for the `Best Technology
j. Winner of a European Medical Device Technology Award 2012 in the
Dental Instruments or Equipment category. http://www.emdt.co.uk/article/taking-lead-medtech-innovation
k. FP7 Cotech final brochure