ISRCTN15334496.

Trial name or title	Periodontal treatment for improving glycaemic control in diabetic patients: a randomised controlled trial Trial acronym: DIAPERIO Trial ID: ISRCTN15334496
Methods	2‐centre, single‐blind RCT
Participants	150 people with type 1 and 2 DM and: ‐ be aged 18 years or older (male or female), ‐ be affiliated to a public health system, ‐ be diagnosed as having had type 1 or 2 diabetes for at least 1 year before V0, ‐ have a last known value of HbA1c, measured within 3 months prior V0, between 6.8% and 9.7%, ‐ have received stable antidiabetic therapy (no changes to diet, medication, dosage or formulation) during the 3 months preceding V0, ‐ have at least 6 natural permanent teeth, ‐ be available for all study visits over 3 months in the dental care departments (V1 to V6), ‐ be able to give their written informed consent
Interventions	Comparison: SRP + OHI + systemic antimicrobial (amoxicillin) + topical antimicrobial (chlorhexidine) versus no treatment Gp A: SRP + OHI + systemic antimicrobial (500 mg amoxicillin tid for 7 days; or if contraindicated to beta‐lactam antibiotics: 300 mg clindamycin bid for 7 days) + topical antimicrobial (chlorhexidine 0.12%) Gp B: No treatment (delayed until 23 weeks, when receive Gp A's allocated treatment)
Outcomes	Primary: HbA1c after 13 weeks Secondary: Quality of life Duration: 13 weeks
Starting date	May 2009
Contact information	Jean‐Noel Vergnes: jn.vergnes@mcgill.ca
Notes	Protocol only May 2013, email from JN Vergnes confirmed that this trial is still recruiting Followed up December 2014, no response from author