Skip to main content
Institute of Dentistry - Faculty of Medicine and Dentistry

Professor Johal’s research enables thousands to Sleepwell

Professor Ama Johal

Deputy Dean Professor of Orthodontics

In collaboration with

  • Dr Joanna Battagel
  • Dr Fatemah Alquatton
  • Dr Preeti Jahaur
  • Dr Priya Shah
  • Dr Bahn Agna

Since 2013, more than 11,000 patients in the UK have benefited from Professor Johal’s life-changing treatment for Obstructive Sleep Apnoea (OSA).

OSA is a common respiratory disorder in the UK, affecting around 12% of middle-aged adults. Airways collapse in the throat while the patient is sleeping, reducing their oxygen levels and disrupting sleep.

OSA reduces a patient’s cardiovascular health, cognitive function and quality of life.

The disorder is also associated with an increased risk of road accidents and developing vascular disease: patients with severe OSA are three times more likely to develop hypertension over four years. This link is so marked that it has been predicted that over 10 years, 23% of patients with severe OSA will have a stroke and 14% a heart attack.

The British Thoracic Society estimates that up to 85% of OSA sufferers are undiagnosed and therefore untreated.

Preventing airway collapse

Professor Johal’s research has increased understanding of OSA and its relationship with a patient’s facial features (or phenotypes) that lead to the collapse of the upper airway (pharynx).

By identifying these factors, Professor Johal was able to highlight the positive role mandibular advancement appliances (MAAs), including the Sleepwell device, play in preventing airway collapse. His discoveries could improve future diagnosis and management, as well as our understanding of the upper airway’s role in OSA.

Breakthroughs in patient assessment

In 2005 – working collaboratively with specialist ear, nose and throat surgeons at the Royal National Throat, Nose and Ear Hospital and funded by a grant from the European Orthodontic Society – Professor Johal’s research led to the introduction of a new modification and application to an imaging technique, using three-dimensional fluoroscopy, that enables dynamic assessment of the upper airways of patients with OSA. As the below video demonstrates, this technique allows the actual airway to be viewed through a microscope camera while the patient is induced into a light state of sleep.

This enables clinicians to identify in real-time the part of the throat that collapses during sleep. Clinicians can also assess how a patient will respond to an MAA device. This combination of simulation and assessment has been transformative, enabling clinicians to successfully predict MAA treatment outcomes.

Reducing the need for surgery – and its risks

In addition, Professor Johal’s new imaging technique significantly reduces the need for surgery and its associated risks. Where surgery is still appropriate, his work has led to more targeted patient interventions.

Drug-induced sedation endoscopy for OSA and MAA treatment is now a standard investigative procedure, used by more than 120 specialist sleep centres in the UK and across Europe.

Transforming patient outcomes

In response to the outcomes of an Australian National Institute for Health Research (NIHR)-funded trial, Professor Johal made some design changes to an Australian MAA, the Sleepwell device.

These modifications allow a patient to adjust (titrate) the device to ease their symptoms. Drawing on patient experience, it was shown that the modified Sleepwell device minimised discomfort and maximised a patient’s ability to use the device correctly over the long term.

According to Dr Quinell, the President of the British Sleep Society, "It is now clear that the most basic [MAAs] are not appropriate for OSA treatment" compared to Johal’s titratable version: Professor Johal’s modified device improved results for 70% of patients.  Since 2013, more than 11,000 patients in the UK have received this life-changing treatment.  

Professor Johal’s modified device improved results for 70% of patients.

Comfortable and popular

Moreover, the customisable nature of the device has made it popular with patients, with a reported 90% treatment acceptance, demonstrated by a minimum usage of MAA seven hours per night, seven days per week.

Professor Johal’s research is the first trial of an MAA device to assess adherence, preference and comfort specifically for the patient. This work has been included in a draft National Institute for Health and Care Excellence (NICE) guideline on the management of sleep-disordered breathing (publication in November 2020 was postponed due to the Covid-19 pandemic but is expected soon).

His team are also developing and trialling predictors of successful adherence with MAA therapy, and new strategies to help individuals use this therapy.

Pioneering sleep medicine education for dentists

Professor Johal’s work has also had a significant impact on dental education and training.

His research has provided the evidence base for a new educational programme promoting dental sleep medicine and better management of OSA. Working with the British Thoracic Society and British Sleep Society, he has developed an introductory course for dentists and a specialist sleep medicine care pathway, endorsed by the Medical Protection Society and CFC Underwriting Ltd.

In 2020, his research informed the content of the first international distance-learning diploma in dental sleep medicine, launched in Summer 2021.

Professor Johal’s work has also raised public awareness of the role of MAA therapy in treating OSA. His evidence in favour of customised MAA versus ready-made devices has been accepted by a number of independent patient charities, such as the Hope2Sleep and the British Sleep Society, enabling even more people to benefit from an improved night’s sleep.

Schools, institutes and research centres

Barts and The London School of Medicine and Dentistry

We are firmly embedded within our east London community, with an approach to education and research that is driven by the specific health needs of our diverse population.

Institute of Dentistry

Based in the thriving and diverse area of Whitechapel, we are committed to delivering the highest quality training to our undergraduates, postgraduates, researchers and staff.

Centre for Oral Bioengineering

The Centre supports clinical academics to work with material scientists to conduct transitional and interdisciplinary research.