A Closer Look at Sensory Processing Disorder

In Psychology Today, author Chantal Sicile-Kira (2010) describes Sensory Processing Disorder (SPD) as a “neurological disorder that causes difficulties with processing information from the five senses: vision, auditory, touch, olfaction, and taste, as well as from the sense of movement (vestibular system), and/or the positional sense (proprioception). For those with SPD, sensory information is sensed, but perceived abnormally. Unlike blindness or deafness, sensory information is received by people with SPD; the difference is information is processed by the brain in an unusual way that causes distress, discomfort, and confusion.”6

Autism and sensory processing disorder are two distinct conditions. Do not assume an individual with SPD will also have autism and vice versa. SPD is very common in individuals with ASD; studies by the SPD Foundation suggest more than three-quarters of children with ASD have significant symptoms of Sensory Processing Disorder.

Heather Miller-Kuhaneck, MS OTR/L BCP helps dental professionals understand sensory defensiveness in the following article taken from the Star Institute for Sensory Processing Disorder website.7

What is Sensory Defensiveness?

Sensory defensiveness has been defined as the behavioral indications of over-reactivity to common sensory experiences (Lane, Miller, & Hanft, 2000; Wilbarger & Wilbarger, 1991). Sensory defensiveness can occur in any of the sensory systems, of which there are really eight, rather than five.

They are as follows:

  1. Tactile system (touch)
  2. Vestibular system (sense of movement in relation to gravity)
  3. Auditory system (sound)
  4. Visual system (sight)
  5. Proprioceptive system (position of our body parts, joints, and muscles, as well as the amount of force being used with movement)
  6. Gustatory system (taste)
  7. Olfactory system (smell)
  8. Inner senses (hunger, elimination, etc.)

Typical over-reactions to sensations others might not find noxious range from mild to severe, depending on the stimuli received and the overall amount of stimuli the child is being exposed to. The range of behaviors includes gaze aversion, physical withdrawal, blocking of the stimuli, vocal outbursts, aggressive behaviors, and tantrums.

A child with sensory defensiveness may exhibit the following during a dental visit:

  • Tendency to pull away from or over-react to unanticipated touch, particularly touch to the face
  • Over sensitivity to teeth cleaning by the hygienist
  • Fear responses to moving backwards in the dental chair
  • Difficulty tolerating the bright light above their head
  • Fear responses to the noises of the dental equipment, including the polishing brush
  • Fear responses to unexpected office noises, such as intercoms, door alarms, or beeps
  • Extreme dislike of the polishing paste due, to the texture
  • Over-reactive gag responses to dental tools or x-ray materials
  • Responses to the smell or feel of the glove materials

Fear responses may escalate to physical responses if the fear is not respected. Typically a child will demonstrate "flight or fight" behaviors. First, they will try to escape from the stimuli that are distressing, but if that cannot occur, they will become more and more physically reactive in any attempt to remove themselves from the situation. A child may be able to tolerate one type of stimuli but become more and more agitated if multiple stimuli are added.

Intervention Strategies for Sensory Defensiveness

Sensory defensiveness is often treated with two types of sensory input: deep touch pressure and heavy work. Deep touch pressure is firm touch provided to the skin by way of massage, vibration, brushing, lycra clothing, ace wraps, sandwiching between pillows, heavy weighted clothing, or lying under something heavy. Heavy work includes any activity that provides resistance to the muscles and joints of the body. Activities such as pushing or pulling something heavy, hanging from a trapeze bar, jumping, lifting or carrying heavy items, or squeezing something against resistance can all be considered heavy work. Using deep touch pressure and/or heavy work before and during distressing events can help calm a child with sensory defensiveness. See the box below for specific ways to use these techniques before or during a dental visit. Lastly, a child with sensory defensiveness will best be able to handle discomforting inputs when they are not unexpected. Using verbal preparation can be very helpful. Before doing anything that involves distressing sensory input, warn the child that it is about to occur so they can be prepared and not startled. Also, giving a set time limit the input will occur may also be helpful (i.e., "we are going to do this until the count of 20," or "we’ll be done when the clock says X," etc.).

Suggestions for Reducing Sensitivity During Dental Visits

  • Have the child wear the X-ray vest during the entire appointment to provide extra weight and deep pressure.
  • Have the parent do oral deep pressure or vibration in the form of electric toothbrush, mini massager, or rubbing with toothette prior to appointment.
  • Have the child eat something very chewy prior to the appointment.
  • Allow the child to have a fidget toy that provides "heavy work" during the session.
  • Have the child wear a heavy or tight hat before and during the appointment.
  • Use firm touch whenever touching the child.
  • Verbally warn the child before each thing you do.
  • Allow child to wear something that blocks the bright lights if he/she is sensitive to this.
  • Allow the child to listen to calming music over headphones if the office noises or equipment noises are distressing.

Conclusion

It is difficult for individuals with sensory defensiveness to cope with the fact others do not share their discomfort and others actually may enjoy situations they find so upsetting. For a child with sensory defensiveness who may not be able to verbalize or even recognize the problem, the accompanying feelings of anxiety and frustration can be overwhelming. Therefore, the impact on functional behavior can be significant. Having a dental professional who is understanding and attempts to make the experience as comfortable as possible by respecting their fears and reducing the level of stimuli that is distressing may make the difference between a visit that is successful and one that is not.