The Mouth Matters in Mental Health Trial -2

A Link Work Intervention to Support Dental Visiting in People With Severe Mental Health Difficulties: The Mouth Matters in Mental Health Effectiveness and Cost-Effectiveness Trial

This clinical trial will evaluate the effectiveness and cost-effectiveness of a link work intervention for supporting people with severe mental health difficulties to attend a routine dental appointment. There are two main outcomes, namely: i) attendance at a routine dental appointment; and ii) oral health quality of life.

The main predictions are that:

1. The link work intervention plus treatment as usual will lead to greater likelihood of attendance at a routine dental appointment, compared with treatment as usual alone.
2. The link work intervention plus treatment as usual will lead to better oral health quality of life, compared with treatment as usual alone.
3. The link work intervention plus treatment as usual will be cost-effective compared with treatment as usual alone.

Study Overview

• Status: Not yet recruiting
• Conditions: Mental Health; Psychosis; Oral Health Care
• Intervention / Treatment: Behavioral: Link work intervention

Detailed Description

Aim: To evaluate the effectiveness and cost-effectiveness of a link work intervention to facilitate dental attendance in people with severe mental illness.

Methods: An effectiveness randomised-controlled trial with integrated cost-effectiveness analysis and process evaluation. 480 participants will be recruited from five NHS Trusts and randomised (ratio 1:1) to either treatment as usual or treatment as usual plus the link work intervention. The link work intervention will follow the manual co-developed and used in the feasibility trial. Blind research assistants will support participants to complete assessments at baseline and after nine-months. The investigators will obtain consent to access participant's dental visiting data via the Business Services Authority. The primary outcomes are i) attendance at a routine dental appointment, and ii) oral health related quality of life. Health economics analysis will assess whether the intervention is cost-effective. A qualitative process evaluation will help to understand how it works and might be implemented.

Results/conclusions: This research hopes to produce the first evidenced-based intervention for improving the oral health of people with severe mental illness. It could help to overcome inequities in dental access.

• Study Type: Interventional
• Enrollment (Estimated): 480
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Dr Palmier-Claus, PhD, DClinPsy; Phone Number: +44 1772 773500; Email: J.Palmier-Claus@lancaster.ac.uk

Study Locations

• United Kingdom
  • Ashton-under-Lyne, United Kingdom, OL67SR
    • Pennine Care Nhs Foundation Trust
    • Contact: Prof Berry, PhD, DClinPsy; Phone Number: +44161 716 3000; Email: Katherine.Berry@manchester.ac.uk
  • London, United Kingdom, SE5 8AF
    • South London and Maudsley NHS Foundation Trust
    • Contact: Dr Onwumere, ClinPsyD; Phone Number: +4420 3228 6000; Email: juliana.1.onwumere@kcl.ac.uk
  • Manchester, United Kingdom, M253BL
    • Greater Manchester Mental Health NHS Foundation Trust
    • Contact: Dr Griffiths, PhD; Phone Number: +44161 773 9121; Email: Robert.Griffiths-2@manchester.ac.uk
  • Lancashire
    • Preston, Lancashire, United Kingdom, PR2 8DW
      • Lancashire & South Cumbria NHS Foundation Trust
      • Contact: Dr Palmier-Claus,, PhD, DClinPsy; Phone Number: +441772 773498; Email: J.Palmier-Claus@lancaster.ac.uk
  • Northumberland
    • Newcastle upon Tyne, Northumberland, United Kingdom, NE3 3XT
      • Cumbria, Northumberland, Tyne and Wear NHS Foundation Trust
      • Contact: Dr Cochrane, ClinPsyD; Phone Number: +44191 246 6800; Email: marsha.cochrane@cntw.nhs.uk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Aged ≥18 years.
• Receipt of care from community mental health or early intervention teams at the point of referral.
• No routine dental appointment (e.g. high street dentist, special care dentist service) in the past three years. This would include any dental examination, diagnosis, advice or treatment (e.g. fillings, root canal, extractions, crowns, dentures, bridges) resulting from a routine (non-emergency) appointment at a dental service. Emergency dental care (e.g. emergency attendance at an Accident & Emergency Appointment or a dental hospital) is not included within this definition, although any follow-up routine and planned appointments with a dentist would exclude the person from taking part.
• Able to provide informed consent as determined by trained researchers in consultation with the clinical team.

Exclusion Criteria:

• Current inpatient status on psychiatric ward. This does not include people in rehabilitation homes or supported accommodation in the community.
• Immediate risk to self or others operationalised as the presence of active intent or planning to harm oneself or others in the near future (e.g. next month). Where individuals are excluded on this basis, with the person's consent, the researcher will aim to re-contact them and/or the referrer in approximately one-months' time to determine if risk has subsided to a point where they are now eligible.
• Enrolled in another dental randomised controlled trial.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Treatment as usual plus a link work intervention; Participants in this arm will receive treatment as usual plus the link work intervention. This will consist of six sessions with a link worker over nine-months who will offer practical and emotional support around accessing a routine dental appointment.	Behavioral: Link work intervention; The mental health link work intervention uses link workers to empower and assist people with severe mental illness currently supported by secondary care mental health services, but not dental services, to access planned dental appointments. The link work intervention in the study proposal has the following dimensions: Delivered by mental health support workers.; Focused on oral health as the primary health issue.; Setting is in secondary mental health care linking to dental care; Primary role is navigating or bridging services.; It builds motivation where needed and offers advocacy.; Its builds self-efficacy and recursively through social persuasion, positive reinforcement, and positive experiences of dental visits and interacting with dental services.; Training and supervision to link workers supports intervention delivery.
No Intervention: Treatment as usual; Treatment as usual will include any treatments or services that the participant would normally have access to outside of the trial. For people with severe mental illness this may include support from a care coordinator, support worker, psychologist, occupational therapist, and/or psychiatrist for care around their mental health. Treatment as usual may include medication and case management. The investigators will monitor, rather than withhold, assessment and treatment for oral health in the treatment as usual arm.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Attendance at a planned care appointments	As measured by the National Health Services Business Services Authority (NHS BSA).	From baseline to nine-month follow-up assessment.
Oral health related quality of life	Oral Health Impact Profile - 14 item version (OHIP-14), range: 0-56, higher scores indicate worse oral health related quality of life	From baseline to nine-month follow-up assessment .

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Self-reported attendance at a planned dental appointment.	Self-report dental attendance items.	From baseline to nine-month follow-up assessment.
Orofacial pain & disability	Manchester Orofacial Pain Disability Scale. Two binary outcomes plus scale. Range: 0-52. Higher scores indicates greater pain (binary) / help seeking (binary) / pain related disability (scale).	From baseline to nine-month follow-up assessment
Confidence around dental visiting	Single item of self-efficacy around attendance. Range 1-7. A higher score indicates greater confidence around dental visiting.	From baseline to nine-month follow-up assessment.
Self-esteem	Rosenberg Self-Esteem Scale. Range: 0-30. A higher score indicates better self-esteem.	From baseline to nine-month follow-up assessment
Dental anxiety	Modified Dental Anxiety Scale. Range: 5-25. A higher score indicates greater levels of dental anxiety.	From baseline to nine-month follow-up assessment.
General anxiety	Generalised Anxiety Disorder Questionnaire. Range: 0-21. A higher score indicates greater levels of anxiety.	From baseline to nine-month follow-up assessment .
Depression	Patient Health Questionnaire - 9 items. Range 0-27. A higher score indicates greater levels of depression.	From baseline to nine-month follow-up assessment.
The number of planned dental appointments attended	Recorded via the National Health Service Business Services Authority.	From baseline to nine-month follow-up assessment.
Self-reported access to free/subsidised dental care.	Self-report items	From baseline to nine-month follow-up assessment.
Exemption status for dental care	As recorded by the National Health Service Business Services Authority	From baseline to nine-month follow-up assessment.
Completion of a course of dental treatment	As record via the National Health Service Business Services Authority.	From baseline to nine-month follow-up assessment.
Self-reported utilisation of urgent or emergency dental services.	Self-report items	From baseline to nine-month follow-up assessment.
Quality adjusted life years	European Quality of Life five-dimensional questionnaire (EQ-5D-5L). Five health dimensions plus overall health score on a visual analogue scale range. Range on visual analogue scale: 0-100. A higher score indicates better health.	From baseline to nine-month follow-up assessment.
Utilization of healthcare resources	Co-designed health economics questionnaire recording utilisation of services and treatment.	From baseline to nine-month follow-up

Collaborators and Investigators

• Sponsor: Lancashire and South Cumbria NHS Foundation Trust
• Collaborators: King's College London; University of Leeds; University of Liverpool; University of Manchester; South London and Maudsley NHS Foundation Trust; Lancaster University; Greater Manchester Mental Health NHS Foundation Trust; Northumberland, Tyne and Wear NHS Foundation Trust; Pennine Care NHS Foundation Trust

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2026
• Primary Completion (Estimated): July 31, 2029
• Study Completion (Estimated): July 31, 2029

Study Registration Dates

• First Submitted: March 10, 2026
• First Submitted That Met QC Criteria: March 10, 2026
• First Posted (Actual): March 13, 2026

Study Record Updates

• Last Update Posted (Actual): March 17, 2026
• Last Update Submitted That Met QC Criteria: March 13, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: mental health; Dentistry; Mouth Matters
• Additional Relevant MeSH Terms: Schizophrenia Spectrum and Other Psychotic Disorders; Mental Disorders; Behavior; Personal Satisfaction; Psychotic Disorders; Psychological Well-Being
• Other Study ID Numbers: NIHR171340; 350197 (Other Identifier: IRAS number (NHS HRA))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Following publication of the trial results, the investigators will make suitable arrangements for anonymised data to be available from the research team, in line with NIHR data sharing guidance. This will be outlined in the Data Access Management Plan (DAMP) developed in the early phases of the project.
• IPD Sharing Time Frame: Exact plans and timescales will be developed during the early phases of the project and outlined within a Data Access Management Plan (DAMP). The IPD will only be available from the point of the results being published and after 31/07/2029.
• IPD Sharing Access Criteria: Exact specifications around who can apply for access to anonymized data and how will be outlined in the Data Access Management Plan (DAMP). Key considerations will include the confidentiality and privacy of participants; respect to the terms of consent by individuals who are involved in research; consistency with relevant legal, ethical and regulatory frameworks; and guarding against unreasonable costs.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No