Sem 2: notes (Ergonomics in Dentistry)

Ergonomics in Dentistry

Definition

  • Ergonomics: Multidisciplinary science studying the relationship between individuals and their environment during work.
  • Goal: Maximize efficiency with minimal worker effort.
  • Dental ergonomics: Applies ergonomic principles to the dentist, assistant, hygienist, technician, patient, and dental office.
  • Four problems of ergonomics:
    • Environmental conditions
    • Devices
    • Individual
    • Work organization

Dental Team

  • Dentist: Heads the team, responsible for all tasks.
  • Dental assistant:
    • Prepares the office.
    • Disinfects and sterilizes equipment.
    • Prepares the patient.
    • Assists during procedures.
    • Maintains documentation.
  • Dental hygienist:
    • Conducts oral hygiene education.
    • Focuses on preventing dental/periodontal diseases.
    • Performs prophylaxis.
    • Performs some therapeutic procedures.
  • Dental technician: Collaborates on rehabilitating the masticatory system, making dentures and orthodontic appliances.

Patient Position

  • Positions:
    • Seated/reclined
    • Supine
  • Supine Position:
    • Reduced risk of choking and fainting.
    • 16-20 body support points.
    • More convenient for the patient.
    • Better access and insight into the treatment area.
    • More convenient for the operator
  • Supine position - Contraindications:
    • Pregnancy (advanced).
    • Obesity (significant).
    • Anxiety.
    • Upper respiratory tract obstruction.
    • Advanced age.
    • Hypertension, angina pectoris.
    • Spinal disease.
    • Young children.
    • Patient examination, oral hygiene examination, taking impressions, occlusal height measurement, selecting the color of artificial teeth, trying on dentures, spinal disease, some orthodontic procedures.

Methods of Working with the Patient

  • Traditional:
    • Patient seated or reclined
    • Dentist stands or sits
  • 2-handed method (solo):
    • Patient supine, dentist sits.
    • Dentist or hygienist or assistant.
  • 4-handed method:
    • Patient supine, dentist sits
    • Dentist + assistant.
  • 6-handed method:
    • Dentist sits.
    • Dentist + 2 assistants.
  • Four-Handed Work Zone:
    • Operational zone:
      • 8.30-12.30
    • Static zone:
      • 12:00 - 2:00
    • Assistant's work zone:
      • 2.00 -4.00
    • Transfer zone:
      • 3.00-9.00

Operator and Assistant's Position

  • Operator's body support levels:
    • I – supporting the fingers on the patient's lips and alveolar process
    • II – supporting the hand and wrist on the patient’s face (forehead, cheeks, chin)
    • III – supporting the operator's elbow (on the torso, armrest)
    • IV – supporting the operator's torso, pelvis and thighs (correct position on the chair)
    • V – supporting the feet on the floor
  • Assistant's position (duo method):
    • Assistant sits higher (eyeline 15-20 cm above operator).
    • Angle between assistant's eyes and patient's oral cavity >= 60∘60^{\circ}.
    • Assistant's thighs in plane with patient's face or at 45∘45^{\circ} angle to patient's midline.

Principles of Ergonomic Work

  • Ensures correct team position and minimizes strain on nervous, musculoskeletal, and visual systems.
  • 5 classes of movements in ergonomics: load force
    • I – fingers
    • II – fingers and wrist
    • III – fingers, wrist and elbow
    • IV – whole arm
    • V – arm and torso
  • Good visibility of the treatment area is key.
  • Principle of parallelism
    • The frontal plane of the operator's face must be parallel to the surface of the tooth being prepared in the direct field of vision or to its mirror image in the indirect field of vision
    • A line drawn from the operator's eyes to the surface of the tooth being prepared should be perpendicular
  • Principle of five changes:
    1) Changing the position of the operator in relation to the patient
    2) Changing the height of the patient's position in relation to the floor
    3) Changing the position of the patient's head (moving left/right)
    4) Changing the position of the patient's head (moving up/down)
    5) Changing how wide the patient opens his/her mouth
  • Ergonomic grips:
    • Two-finger grip
    • Three-finger grip
    • Writer's grip
    • Modified writer's grip
    • Palm grip
  • Methods of handing over instruments
    • One-handed - \"pass-take\"
    • Two-handed