بسم الله الرحمن الرحيم
Mechanisms leading to musculoskeletal disorders
in dentistry
What Factors Contribute to What Factors Contribute to WMSDsWMSDs??
WMSD Symptoms Among WMSD Symptoms Among DentistsDentists
0%10%20%30%40%50%60%70%80%
Body Part
% R
ep
ort
ing
Males
Females
Source: Finsen et al., 1998
WMSD Symptoms WMSD Symptoms Among Dental Among Dental HygienistsHygienists
01020304050607080
*DiagnosedCTS
*Hand-wristpain
*Shoulderpain
*Neck pain Low Backpain
% R
epo
rtin
g
Dental Hygienists Dental Assistants
Source: Liss et al., 1995* indicates difference is significant
Prevalence of musculoskeletal disorders among orthodontists in Alberta
0
10
20
30
40
50
60
LBP shoulder
Male
Female
Neck
In a 1946 study, Biller found operators.
0
20
40
60
80
LBP
196419901996
What Factors Contribute to What Factors Contribute to WMSDsWMSDs??
Fixed or awkward Fixed or awkward posturespostures Neck, back, shoulder Neck, back, shoulder
postureposture Hand/wrist positionsHand/wrist positions Standing/sittingStanding/sitting Operatory organizationOperatory organization Patient positioningPatient positioning
When operators sit, pain occurs not only in their backs, but also their necks, shoulders and arms.
operators who primarily stood experienced low back pain (65.7 percent), as well as neurocirculatory disease including varicose veins (66.7 percent), postural defects (77 percent) and flatfoot (60.1 percent).
Contributing Factors for Contributing Factors for WMSDsWMSDs
Do not focus solely on the workplaceDo not focus solely on the workplace Risk factors may be experienced Risk factors may be experienced
during non-occupational activities during non-occupational activities (e.g., certain sports, exercising, (e.g., certain sports, exercising, working with computers, needlework, working with computers, needlework, playing musical instruments)playing musical instruments)
Neck and Shoulder Neck and Shoulder DisordersDisordersbahu dan leherbahu dan leher gangguangangguan
Risk factors associated with Risk factors associated with dentistrydentistry Prolonged static neck flexion and Prolonged static neck flexion and
shoulder abduction or flexionshoulder abduction or flexion
Lack of upper-extremity supportLack of upper-extremity support
Inadequate work breaksInadequate work breaks
MUSCLE IMBALANCES
Forward bending Repeated rotation of the head, neck
and trunk to one side Over time, the muscles responsible
for rotating the body to one side can become stronger and shorter, while the opposing muscles become weaker and elongated
lengtheninglengthening
shorteningshortening
lengthening or shortening
muscle imbalance
muscle imbalance
ketidakseimbangan otot
ketidakseimbangan otot
Pectoralis minor Shortening