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SIXES: Should I eXtract Every Six? A Study of the Extraction of Permanent Molar Teeth in Children.

SIXES: Should I eXtract Every Six? A Randomized Clinical Trial of the Extraction of First Permanent Molar Teeth in Children

Status
Terminated
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01591265
Acronym
SIXES
Enrollment
7
Registered
2012-05-03
Start date
2014-05-31
Completion date
2015-03-25
Last updated
2018-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Paediatric Dentistry

Keywords

Compensatory dental extraction, Children 7-11 years old

Brief summary

This clinical trial investigates relative benefits (clinical effectiveness and quality of life) of two extraction patterns when lower first permanent molars (FPM) are extracted in children The study objectives are to determine whether compensating extraction of upper FPMs following loss of lower FPMs in children is of benefit. The particular benefits being investigated are related to the resulting occlusion, patient experience and oral health related quality of life. The follow up will extend over a period of 5 years or until the patient is 14 years of age - whichever is earlier.

Detailed description

The study has been designed as a randomised controlled clinical trial. The control group will have the normal standard intervention receiving routine patient care with the normal practice of upper and lower extractions, whilst the intervention group will have removal of the lower tooth but no upper extraction. Study recruitment will take place over an 18 month period and will be based in the Dundee Dental Hospital Orthodontic and Paediatric Dentistry Departments. Patients are referred to this department from their General Dental Practitioner. Consent of the patients will be carried out by the attending dentists who will have received training on the study design and protocol, including RGF and consenting patients for clinical trials. Data will be collected contemporaneously using the Case Report Forms. Additional data which will be collected for the purposes of the study will include COHQoL questionnaires and measurements from 3D images of models of the teeth. At subsequent 1 year and five year review visits dental study 3D models will be repeated, and the CRF completed together with the COHQoL questionnaire for that visit.

Interventions

PROCEDUREExtraction of upper and lower FPM teeth

Extraction of upper and lower FPM teeth

PROCEDUREExtraction of lower FPM tooth

Extraction of lower FPM tooth only

Sponsors

NHS Tayside
CollaboratorOTHER_GOV
Professor David Bearn
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
7 Years to 11 Years
Healthy volunteers
No

Inclusion criteria

* Age: 7 -11 years * Dental History: Able to co-operate with dental treatment * Regular attender or considered likely to return for follow-up Social History * Child and carer able to understand study documentation and give consent to participate in study Dental condition: * One or two lower FPMs requiring extraction * Upper FPMs are sound or restorable/ restored with good long term prognosis (i.e. has or requires a single surface restoration with caries less than half-way into dentine, restoration with a simple restoration) * Confirmed presence of all second premolars and all second molars

Exclusion criteria

* Medical History: Medical contraindication to dental extractions * Dental condition: Poor prognosis of premolars or permanent second molar teeth * All four upper incisors in crossbite * Poor prognosis of upper FPM * Confirmed absence of one or more second premolars and second molars * Declines to have impressions taken

Design outcomes

Primary

MeasureTime frameDescription
Extent of tipping of the lower second permanent molars5 yearThe primary outcome measure is extent of tipping of the lower second permanent molar, with a favourable outcome being a degree of tipping less than 15°, and unfavourable outcome being greater than 15°. Participants will be allocated into 'favourable' or 'unfavourable' outcome groups when comparing study models, cast from dental impressions taken at baseline with 1 year and 5 year follow up or when the patient reaches 14 years of age, whichever is first.

Secondary

MeasureTime frameDescription
residual spacing between the lower second permanent molar and the lower second premolar*;1 year and 5 yearOutcome be measured on study models of the teeth, cast from impressions taken at baseline and after 1 year and 5 years or when the participant reaches 14 years of age, whichever is first.
American Board of Orthodontics (ABO) scores1 year and 5 yearOutcome will be measured on study models of the teeth, cast from impressions taken at baseline and after 1 year and 5 years or when the participant reaches 14 years of age, whichever is first.
position of the upper FPMs with regard to over-eruption1 year and 5 yearThe secondary outcomes for the study are: 1.position of the upper FPMs with regard to over-eruption;Outcome will be measured on study models of the teeth, cast from impressions taken at baseline and after 1 year and 5 years or when the participant reaches 14 years of age, whichever is first.
dental or orthodontic treatment carried out during the follow-up period1 year and 5 yearTo compare if there is a difference in the frequency or type of dental or orthodontic treatment between the two groups of children.
Child and Parent Oral Health Related Quality of Life (OHRQoL) scores1 year and 5 yearChild and Parent Oral Health Related Quality of Life (OHRQoL) scores (child and parent questionnaires)will be assessed at one year and 5 year follow up and compared with baseline.
the type of anaesthetic used during proceduresat baseline onlyCompare whether there is a difference in the type of anesthetic used by the dentist dependent on the intervention allocated.

Countries

United Kingdom

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Mar 24, 2026