The aim of this in situ study is to investigate whether occlusal loading leads to increased secondary caries formation in loaded compared to unloaded samples in a near-clinical environment.
ID
Source
Brief title
Condition
- Other condition
Synonym
Health condition
secundaire cariës
Research involving
Sponsors and support
Intervention
Outcome measures
Primary outcome
The main study parameters are lesion depth (µm) and integrated mineral loss
(µm.vol%) in the tooth sample close to the restoration margin. These will be
measured through the microradiographic technique T-WIM.
Secondary outcome
Secondary study parameters include:
- salivary flow (ml/min)
- location and measure of chewing forces, measured using T-scan device
Background summary
Secondary caries is tooth decay next to an existing restoration and one of the
main reasons to replace restoration in general dental practice. Previous
research has shown that secondary caries lesions can develop when a small gap
is present between the tooth and restorative material. Gaps as small as 30 µm
have been shown to develop secondary caries lesions in vitro and in situ [Kuper
et al., 2014; Maske et al., 2019; Maske et al., 2017].
Presence of a gap allows the formation of a wall and surface lesion next to a
dental restoration. An in vitro study by Kuper et al. [2013] showed that an
increased hydrodynamic flow in the gap between composite and tooth material
leads to an increase in wall lesion development.
A more recent study by Askar et al. [2017] found that loading a
tooth-restoration sample containing a gap of 100 µm width led to increased
caries lesion formation compared to unloaded samples. They theorized that the
loading on the sample containing a gap could lead to compression of the gap
area. When the force is released, the compression ends, and the gap returns to
normal. This cyclic deformation of the gap area could possibly lead to an
increased hydrodynamic flow, which explains the increase in lesion formation in
loaded samples.
Since only in vitro data is available on this topic, the clinical relevance is
so far unclear. Whether the effect of loading of restorations still influences
the secondary caries process in a more variable clinical environment, is
unknown.
Study objective
The aim of this in situ study is to investigate whether occlusal loading leads
to increased secondary caries formation in loaded compared to unloaded samples
in a near-clinical environment.
Study design
A mono-center, single blind in situ study, with split-mouth design.
Edentulous subjects will receive a duplicate of their lower denture containing
sterilized tooth samples in slots. Half the samples will be placed in occlusal
contact with the upper denture. The other half will be placed slightly lower,
out of contact. The appliance has to be dipped in 20% sucrose solution 4 times
a day for 10 minutes. The appliance containing samples needs to be worn for 6
weeks, 24 hours a day.
Study burden and risks
No intervention is carried out specifically on the participants themselves,
since the samples are removable and can be exposed and analysed out of the
volunteers* mouths. There are four visits associated with participation in this
study.
The volunteers are requested to wear the denture close to 24 hours a day for 6
weeks and are only removed for cleaning. This increases the risk of soft tissue
discomfort, since dentures are usually worn only 16-18 hours a day.
Swallowing one of the tooth samples is a relative risk. Securing the tooth
samples in the slots of the appliance with the help of composite material in an
undercut has proven to minimize this risk in earlier studies (NL33528.01.11,
NL.47343.091.14). No benefit can be expected since no intervention is performed
directly on the volunteers.
Philips van Leijdenlaan 25
Nijmegen 6525 TX
NL
Philips van Leijdenlaan 25
Nijmegen 6525 TX
NL
Listed location countries
Age
Inclusion criteria
• Adults (>18 years)
• Have a full denture in the lower jaw
• Have a lower denture height of at least 8 mm
Exclusion criteria
• ASA score >2
• Unable to give informed consent
• Unable to understand written patient information
Design
Recruitment
Followed up by the following (possibly more current) registration
No registrations found.
Other (possibly less up-to-date) registrations in this register
No registrations found.
In other registers
| Register | ID |
|---|---|
| CCMO | NL71551.091.19 |
| Other | NL8031 |