INVESTIGATING HYPNOSIS FOR THE ALLEVIATION OF DENTAL ANXIETY DOES THE ADDITION OF HYPNOSIS TO INHALATION SEDATION REDUCE DENTAL ANXIETY MORE THAN INHALATION SEDATION ALONE A thesis submitted to the University of Manchester for the degree of Doctor of Philosophy (PhD) in the Faculty of Medical and Human Sciences 2013 CATHERINE POTTER SCHOOL OF DENTISTRY CONTENTS Table of Contents Abstract ....................................................................................................... 14 Declaration .................................................................................................. 15 Copyright statement................................................................................... 15 Dedications and Acknowledgements ........................................................ 16 CHAPTER 1 Literature Review ............................................................... 17 Historical Background ............................................................................... 18 Dental Anxiety ............................................................................................ 22 Prevalence ................................................................................................ 22 Aetiology .................................................................................................. 26 Conditioning ......................................................................................... 26 Cognitive factors .................................................................................. 28 Specific treatment factors ..................................................................... 31 Effects of the Dentist – Patient Relationship ....................................... 32 Familial and cultural influences ........................................................... 33 Other factors ......................................................................................... 34 A multi-factorial Aetiology .................................................................. 36 Treatment Methods for Dental anxiety .................................................... 37 Behavioural treatment methods for dental anxiety .............................. 37 Treatment methods based on the cognitive aspects of dental anxiety . 39 Provision of information ...................................................................... 42 Systematic desensitisation or exposure therapy ................................... 43 Flooding ............................................................................................... 44 2 Comparisons between pharmacological and behavioural treatments ...... 45 Inhalation Sedation .................................................................................... 47 Mechanism of Action ............................................................................... 47 Effectiveness ............................................................................................ 50 Disadvantages .......................................................................................... 52 Hypnosis ...................................................................................................... 57 Theoretical Overview ............................................................................... 57 Historical overview .............................................................................. 57 Individual Differences in Response to Hypnotic Procedures .............. 59 Rapport ................................................................................................. 60 Current Theories of Hypnosis .................................................................. 60 Clinical Hypnosis ..................................................................................... 62 Individual differences and hypnotisability in clinical hypnosis ........... 63 Hypnosis in Anxiety and Phobia .......................................................... 64 Hypnosis in Surgical Procedures ......................................................... 65 Hypnosis in Dentistry ............................................................................... 67 Hypnosis for Dental Anxiety and Phobia............................................. 69 Hypnosis methods used for dental anxiety and fear............................. 72 Conclusions .............................................................................................. 73 Inhalation Sedation Hypnosis and Suggestion ........................................ 73 Influencing the Actions of Inhalation Sedation by Manipulating Expectancy ............................................................................................... 73 Influencing the Actions of Hypnosis by Manipulating Expectancy ........ 75 Influencing the Actions and Effectiveness of Inhalation Sedation using Hypnosis ................................................................................................... 76 3 Influencing the Actions of Hypnosis using Nitrous Oxide? .................... 78 Summary .................................................................................................. 80 CHAPTER 2 Hypnosis for alleviation of anxiety in adults undergoing dental treatment A Systematic review...................................................... 82 Part 1 ........................................................................................................... 83 A Cochrane Protocol .................................................................................. 83 Background .............................................................................................. 83 Description of the condition ................................................................. 83 Description of the intervention............................................................. 84 How the intervention might work ........................................................ 85 Why it is important to do this review ................................................... 86 Objectives ................................................................................................. 88 Methods .................................................................................................... 88 Criteria for considering studies for this review .................................... 88 Search methods for identification of studies ........................................ 90 Data collection and analysis ................................................................. 92 Appendix 1 ............................................................................................... 98 MEDLINE (OVID) search strategy ......................................................... 98 Contributions of authors ........................................................................... 99 Declarations of interest .......................................................................... 100 Sources of support .............................................................................. 100 References .............................................................................................. 101 Additional references ......................................................................... 101 Part 2 Results Discussion and Conclusions ............................................ 105 Results ........................................................................................................ 105 4 Description of studies ......................................................................... 105 Included studies ...................................................................................... 108 Characteristics of the trials ................................................................. 108 Characteristics of the participants ...................................................... 108 Characteristics of Interventions and control procedures .................... 113 Characteristics of outcome measures ................................................. 121 Excluded studies................................................................................. 131 Risk of bias in included studies .......................................................... 131 Effects of interventions ...................................................................... 147 Discussion .............................................................................................. 167 Summary of main results ................................................................... 167 Overall completeness and applicability of evidence .......................... 170 Quality of the evidence ...................................................................... 170 Agreements and disagreements with other studies or reviews........... 171 Authors' conclusions .......................................................................... 172 Reflections on the process of the review ........................................... 173 CHAPTER 3 Production of Experimental Anxiety in the Dental Setting .................................................................................................................... 174 Rationale ................................................................................................... 175 Production of Temporary Experimental Anxiety ................................... 176 Measuring dental anxiety ....................................................................... 178 Physiological Correlates of Anxiety ...................................................... 181 Experiment 1 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