Impacted Third Molar (Wisdom Tooth) and Issues Related to It

Impacted  Tooth : A tooth which is completely or partially unerupted and is positioned against another tooth, bone or soft tissue so that its further eruption is unlikely,described according to its anatomic position.   (American society of oral surgeons 1971)

causes:Local causes

 Obstruction of the eruption 

Compact bone

Dense soft tissue

 Premature loss /Retained  deciduous tooth 

 Scar   tissue  

Gingival  fibromatosis 

 Cyst  formation, Odontogenic  tumor

Ankylosis(tooth fused with bone)

Change in angulation of the tooth 

Chronic inflammation

Reduced jaw growth

Irregularities of adjacent tooth 

Arch length tooth material discrepancy

Ectopic position(other than normal position) of tooth bud

Symptoms

Symptoms include:Swelling of the gum in the back of your mouth

Difficulty opening your jaw

Bad breath A bad taste in the mouth

Pain when you open your mouth

Pain when chewing or biting

Pain can occur for several days and then disappear. It can come back weeks or months later.

Diagnosis

Your dentist will examine the area. If necessary, he or she will take X-rays. X-rays can show where your wisdom teeth are and if they are impacted.

Expected Duration

When the tooth is taken out, the symptoms will go away.

When To Call a Professional 

Call your dentist if you feel pain in your back teeth. If you visit your dentist regularly, he or she will keep track of your wisdom teeth and let you know if you need to have them taken out. Your dentist may take extra X-rays to check your wisdom teeth. Routine X-rays often don’t show these teeth.

Prognosis

The outlook after surgery is excellent.

 WHY TO GET IT REMOVED >>>>>>>

1) PAIN AND INFECTION 

2) DAMAGE TO ADJACENT TOOTH

3) WILL LEAD TO CROWDING OF ANTERIOR TOOTH (MAL-ALIGNMENT)

4) MIGHT LEAD TO MANDIBULAR FRACTURE

Weak areas : angle, condyle & parasymphysis region.

Frequency of occurrence of mand. angle # is higher in pts,with impacted lower third molars & that of condylar # is higher in pts, without it.   (Lida &colleagues,2004)

Mechanism: occupy osseous space decreasing cross-sectional area of bone. Absence of unerupted 3rd molars is significantly associated with higher incidence of condylar #. Combination of symphysis & condyle # seen in cases without impacted lower third molars.   (Zhu et al , 2005)

5)RISK OF CYST & TUMOR DEVELOPMENT:–

Most common age : 20- 25 years.

Incidence of cyst formation-2.31%     (Guven et al,2000)

Incidence of dentigerous cyst-1.6%   (Keith,1973)

Incidence of ameloblastoma –0.14- 2% (Shear,1978)