Habitual grinding or clenching of the teeth, either during sleep or as an unconscious habit.
Etiology
Local factors
Systemic factor
Psychologic factors
2. BRUXISM
• Habitual grinding or clenching of the teeth, either
during sleep or as an unconscious habit.
Etiology
• Local factors
• Systemic factor
• Psychologic factors
3. CLINICAL FEATURE
1. Effect on dentition
2. Effect on periodontium
3. Effects on the masticatory muscle
4. Psychological and behavioral effect
5. TETANUS
• An active potential fatal infection of the nervous
system characterized by intense activity of motor
neurons and results in severe muscle spasm.
• ETIOLOGY=exotoxins of anaerobic, gram positive
bacillus clostridium tetani which is commensal of
human and animal GIT.
Shafer’s textbook of oral pathology, 6th Edition
6. SOURCE OF INFECTION
• It is common in areas where the soil is cultivated,
rural areas, warm climates and during summer.
• Occur after acute injuries such as laceration or
abrasion, in patient with ulcer, gangrene etc.
7. • bottom of the groove cut by the buccinator muscle proved to
correspond with the occlusal plane.
• This suggested a simple method of locating the correct position for
the occlusal plane for full dentures.
8. • The second vestibule impression was made with the corner of the
mouth well puckered in, that is with the modiolus tensed .
• This second impression showed the imprint of the tensed triangular
muscle, as well as the partially tensed buccinator muscle.
9. • The third vestibule impression was made with the buccinator muscle
tensed, that is, with the corner of the mouth drawn well back.
• This showed the well defined imprint of the buccinator.
11. GENIOGLOSSUS MUSCLE
• In the midline superficially, we note the frenulum of the tongue. Just
beneath it is the fan shaped genioglossus muscle, the extended
aspect forming the vertical center mass of the tongue.
• It is composed of three groups of fibers: the anterior, the middle, and
the posterior.
12. • The anterior fibers arise from the superior mental spine ; and, curving
upward and backward, they form the anterior underside of the
tongue as well as its tip.
• The middle and posterior fibers pass distally; some of the posterior
fibers also pass downward to gain attachment to the hyoid bone.
13. • The only fibers of this muscle that can, when
tensed, impinge on a lower denture base are the
anterior group.
• Tension of these muscles will curl the tongue tip
down into the floor of the mouth.
14. • Protrusion of the tongue is brought about by tension of the posterior
group of fibers, and none of these can impinge on a denture base.
Simultaneous tension of all three groups of fibers of this muscle curls
the tongue tip downward and forces it firmly against the lingual
surfaces of the lower incisors.
15. MUSCLE OF HYOID BONE
• Just below the attachment of the genioglossus to the mandible, we
find the inferior mental spine from which arises the geniohyoid
muscle.
• It is a thin, narrow muscle which passes downward and backward to
gain attachment to the hyoid bone.
16. • Immediately below the geniohyoid muscle in the median line, we find
the mylohyoid muscle, which is a thin, wide muscle that forms the
muscular floor of the mouth.
17. • Each lateral half of the muscle is fan-shaped with
the base of the fan attached to the hyoid bone.
• The extended part is attached to the mylohyoid
ridge on the medial surface of the mandible back
to the third molar region.
• In the bicuspid region, we find the sublingual gland
overlying the mylohyoid muscle.
18. • If a proper impression technique is employed, this
region frequently shows a place where a tongue
rest for a lower denture can be provided ; or we
may find a crypt that will accommodate a fairly
large extension downward of the lingual flange of
a lower denture, thus helping greatly to ensure
stability and retention.
20. • The aim of the study is to determine association between depressive
symptoms and the electrical activity of muscles in maximum
voluntary clench in a group of young adults.
21. Material and method
• A total of 186 volunteers (Females = 98, Males = 88), with a mean
age of 19 years, were recruited to the study.
• All participants took a questionnaire survey stating the level of
depression (Beck’s scale), clinical examination, and instrumental
diagnostics (EMG).
22. Result
• Symptoms of mild or medium depression were found in 35 of the
subjects (18.82%). Average electric potentials of the masticatory
muscles in maximal voluntary clench were significantly higher among
the subjects with depression symptoms in comparison with subjects
without those symptoms.
23. REFERRENCES
• Human physiology, Dr. A K Jain 6th Edition.
• Human anatomy, B D Chaurasia 3rd Edition.
• Okeson 6th Edition
• JJ Sharry
• shafer’s textbook of oral pathology 6th Edition
