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

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

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.

Study Overview

• Status: Terminated
• Conditions: Paediatric Dentistry
• Intervention / Treatment: Procedure: Extraction of upper and lower FPM teeth; Procedure: Extraction of lower FPM tooth

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.

• Study Type: Interventional
• Enrollment (Actual): 7
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • Angus
    • Arbroath, Angus, United Kingdom, DD11
      • Springfield Community Dental Practive
  • Dumfries & Galloway
    • Dumfries, Dumfries & Galloway, United Kingdom, DG1 4AP
      • Dumfries & Galloway Royal Infirmary
  • Tayside
    • Dundee, Tayside, United Kingdom, DD1 9SY
      • Dundee Dental School, University of Dundee
    • Dundee, Tayside, United Kingdom, DD3 8EA DD3 8EA
      • Kingscross Hospital Community Dental Service
    • Perth, Tayside, United Kingdom, PH1 1TJ
      • Broxden Community Dental Practice

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 5 years to 9 years (Child)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Compensatory Extraction; Patients allocated to this group, both the upper FPM and lower FPM teeth will be extracted.	Procedure: Extraction of upper and lower FPM teeth; Extraction of upper and lower FPM teeth
Active Comparator: No Compensatory Extraction; Patients allocated to this group, only the lower FPM tooth will be extracted.	Procedure: Extraction of lower FPM tooth; Extraction of lower FPM tooth only

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Extent of tipping of the lower second permanent molars	The 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.	5 year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
position of the upper FPMs with regard to over-eruption	The 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.	1 year and 5 year
residual spacing between the lower second permanent molar and the lower second premolar*;	Outcome 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.	1 year and 5 year
American Board of Orthodontics (ABO) scores	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.	1 year and 5 year
the type of anaesthetic used during procedures	Compare whether there is a difference in the type of anesthetic used by the dentist dependent on the intervention allocated.	at baseline only
dental or orthodontic treatment carried out during the follow-up period	To compare if there is a difference in the frequency or type of dental or orthodontic treatment between the two groups of children.	1 year and 5 year
Child and Parent Oral Health Related Quality of Life (OHRQoL) scores	Child 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.	1 year and 5 year

Collaborators and Investigators

• Sponsor: Professor David Bearn
• Collaborators: NHS Tayside
• Investigators: Principal Investigator: David R Bearn, MOrth MFDS, University of Dundee; Principal Investigator: Nicola Innes, PhD, MFDS,, University of Dundee

Publications and helpful links

General Publications

• Innes N, Borrie F, Bearn D, Evans D, Rauchhaus P, McSwiggan S, Page LF, Hogarth F. Should I eXtract Every Six dental trial (SIXES): study protocol for a randomized controlled trial. Trials. 2013 Feb 27;14:59. doi: 10.1186/1745-6215-14-59.

Study record dates

Study Major Dates

• Study Start: May 1, 2014
• Primary Completion (Actual): March 25, 2015
• Study Completion (Actual): March 25, 2015

Study Registration Dates

• First Submitted: April 30, 2012
• First Submitted That Met QC Criteria: May 1, 2012
• First Posted (Estimate): May 3, 2012

Study Record Updates

• Last Update Posted (Actual): June 29, 2018
• Last Update Submitted That Met QC Criteria: June 27, 2018
• Last Verified: June 1, 2018

More Information

Terms related to this study

• Keywords: Compensatory dental extraction; Children 7-11 years old
• Other Study ID Numbers: 2011DE02