A balanced randomised controlled trial to examine the usefulness of alginate and polyvinylsiloxane as impression materials for cobalt chromium partial dentures.

ISRCTN	ISRCTN22203853
DOI	https://doi.org/10.1186/ISRCTN22203853
Protocol serial number	N0013146124
Sponsor	Department of Health
Funders	Guy's and St. Thomas' NHS Foundation Trust (UK), Own account, NHS R&D Support Funding

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Record updated in last year

Plain English summary of protocol

Not provided at time of registration

Dr Michael Fenlon
Scientific

Dental Prosthetics
Room 304, 25th Floor, Guy's Tower
Guy's Hospital
St Thomas' Street
London
SE1 9RT
United Kingdom

Phone	+44 (0)20 7188 7479
Email	michael.fenlon@kcl.ac.uk

Primary study design	Interventional
Study design	Randomised controlled trial
Secondary study design	Randomised controlled trial
Scientific title
Study objectives	That there is no difference between the fit of cobalt chromium partial dentures made using irreversible hydrocolloid impressions and those made using polyvinylsiloxane impressions.
Ethics approval(s)	Not provided at time of registration
Health condition(s) or problem(s) studied	Oral Health
Intervention	This is a randomised controlled trial, patients having cobalt chromium bonded saddle partial dentures made at Guy's Hospital will be randomised into two groups, comparing master impressions for partial dentures made using either irreversible hydrocolloid or polyvinylsiloxane impression material. Fit of the resulting cobalt chromium castings will be judged using an accepted method on master models and in the mouth, before and after adjustment. The amount of adjustment, if any, will be noted. Numbers of acceptable and unacceptable castings will be recorded. Added July 2008: the trial was stopped due to lack of funding.
Intervention type	Drug
Phase	Not Specified
Drug / device / biological / vaccine name(s)	alginate and polyvinylsiloxane
Primary outcome measure(s)	Fit of denture castings, need for adjustment and acceptability.
Key secondary outcome measure(s)	Not provided at time of registration
Completion date	31/08/2005
Reason abandoned (if study stopped)	Lack of funding

Participant type(s)	Patient
Age group	Not Specified
Sex	Not Specified
Target sample size at registration	100
Key inclusion criteria	100 patients attending Guy's Hospital for bounded saddle partial dentures.
Key exclusion criteria	Not provided at time of registration
Date of first enrolment	01/09/2004
Date of final enrolment	31/08/2005

Dental Prosthetics

London
SE1 9RT
United Kingdom

Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
IPD sharing plan