This document discusses nerve injuries that can occur during oral surgery procedures. It describes the three branches of the trigeminal nerve and the most common nerves injured, which are the inferior alveolar, mental, and lingual nerves. Symptoms of nerve injury are outlined. Nerve injuries are classified and causes discussed, including during dental injections, extractions, and implant placement. Treatment depends on the type and severity of injury.

1. Made by : Dr. Saya Mustafa
Oral surgery department

2. 1. Nerve supply
2. What is nerve injury ?
3. Most common injured nerves
4. Sign & symptoms
5. Classification
6. Etiology
7. Prognosis
8. Treatment

3.  It has 3 branches :
 1. opthalmic V1->sensory root
 2.Maxillary V2-> sensory root
 3.Mandibuler V3 -> sensory and motor roots

4. 1. Branchiomotor Component: controls the
muscle of facial expression that has 5
branches : Temporal , zygomatic , buccal ,
mandibuler and cervical .
2. The special sensory component: fibers are
carried by chordo tympani join the lingual
nerve provide taste sensation to anterior
2/3 of tongue

6.  Nerve injury is most serious
complication that may occur during
oral surgical procedures especially
when we are damaging large nerve
branches such as during dental
injections , RCT , insertion of dental
implants , extraction of teeth & other
surgical treatments ...etc.

7.  The most common nerve injuries are
of the inferior alveoler nerve , mental
and lingual nerves of V3 branch of
trigeminal nerve which cause sensory
disturbance in the inerveted area .

8.  1. numbness or pain in the chin , lip , gums
and tongue.
 2.tingling or electric shok sensation
 3.impaired speech
 4.loss of taste
 5. abnormal chewing
 6.biting of tongue and lips
 7.burning sensation
 8.paralysis ( bells palsy )

9.  1.Neurapraxia: has favorable prognosis &
occur after simple contact with the nerve and
nerve conduction failure is temporary and
complete recovery which quite rapid and
occurs gradually within few days to weeks.
 2.Axonotmesis: this serious injury of the
nerve resulting in degeneration of the nerve
axons ,
 regeneration & recovery is slower than
neurapraxia & usually begins as paresthesia
6-8 weeks after the injury .

10.  3.Neurotmesis :this is the gravest type of
nerve injury resulting in discontinuation of
conduction due to severance of the nerve or
due to formation of scar tissue at the area of
trauma and cause permanent damage to
nerve function including paresthesia

11.  1. During nerve block of IAN & Mental nerve (
deep dental injection ) .
 2. While creating incision extend to mental
formen & lingual vestibuler fold .

12.  3. during incision at the alveolar ridge of
edentolous pt whose mental foramen located
superficially due to bone resoption

13. 4. during excessive flap retraction
5. when bone near the nerve is excessively heated ,if
the surgical handpiece used without coolent ( water
or saline solution )

14.  6. in case of removel impacted tooth , root &
root tips that are deep in the bone which is
near the nerve.

15.  7.during perforation & fracture of lingual
cortical plate during sectioning of the roots
and crown of impacted 3rd moler.
 8.when a bur enters the mandibuler canal ,
during sectioning.

16.  9.during displacement of a root tip inside the
mandibuler canal during extraction attempt.

17.  10. during cleaning of periapical lesion oa
posterior teeth that are in direct contact with
mand. canal .
 11. or by chance
Suturing of the
Nerve .

18.  12. during putting implant

19.  13. during endodontic treatment because of
proximity of the tooth to IAN by over-
instrumentation or overfilling or irrigation.

20.  Facial palsy : caused by trauma to the facial
nerve .
 -Sign & symptoms :
 1. unilateral facial weakness
 2. loss of taste
 3. decreased salivation
and tear secretion

21.  1. during surgury by incision such as
parotidectomy : “removel of the parotid
gland “ , or condylectomy: TMJ ankylosis , or
surgical approach to the submandibuler
gland .
 2. Giving Anesthesia
during Nerve block
To parotid gland .

22.  Depends on the age of patient , type of the
damage , time that elapsed till the management
of injury , correct treatment.
 Treatment :
 No treatment required for type 1 & 2 unless if there
foreign body or root tip compressing on the nerve we
just prescribe analgesic & vitamin B to restore the
sensation .
 Treatment of the neaurotmesis is grafting to replace
the injured part or suturing .
 For bell’s palsy is often treated with the corticosteriod