The fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) defines phobia as a marked fear or anxiety towards an object or specific situations and contemplates, in this field, the specific form of phobia of needles, actually included in a wider field (blood-injury-injection, BII) which is characterized by high familiarity and a strong tendency to avoid trigger situations, largely related to the health environment. The problem normally occurs from 5.5-10 years of age and, in the dental context, represents an important voice in that framework defined dental anxiety. Early interception may be the key measure for effective treatment to prevent unpleasant dental experiences in the future.
Research methods such as self-assessment questionnaires and psychometric scales are useful from an academic point of view (they are used in both epidemiological and experimental studies) and characterize the behavioral picture of an anxious patient in practice. A more articulated diagnosis; i.e., the distinction between intraoral injection fear and phobia proper, is, however, a matter for specialist figures in the field of psychology and psychiatry.
Intraoral injection fear: a study based on 1460 subjects
On this basis, the working group coordinated by Berge, active at the University of Bergen in Norway, has proposed to develop a scale specifically indicated for dental patients of pediatric-adolescent age. Psychologists and dentists with experience in dental phobia and cognitive behavioral therapy participated in the drafting of the Intra-Oral Injection Fear Scale (IOIF-scale). The validation study was published in 2017 in the International Journal of Pediatric Dentistry, and it was proposed to indicate a cutoff score for the definition of a high level of intraoral injection fear, a condition that may merit further specialist study.
The study involved a large non-clinical sample, consisting of 1460 subjects between 10 and 16 years old, and a clinical sample of 67 of the same age belonging to a Centre for Dental Phobia. The IOIF-scale includes a questionnaire composed of 12 items, to cover the two components: “contact fear” and “distal fear.” Each item must be answered with a minimum score (1) indicative of the absolute absence of fear, up to a maximum (5), which means “very scared.”
The analysis evaluated the internal consistency of the questionnaire (alpha Cronbach = 0.95) and confirmed the ability of the test to discriminate phobic and non-phobic subjects. The ROC (receiver-operating characteristic) curve, moreover, identified in the score of 38 the high-level cutoff of intraoral injection fear. It is applicable to a large population as in the clinical setting.