1. BDS, LDSRCS, MSc, FFDRCSI Specialist Oral Surgeon
Mr. Kameran Al- Naib
BDS, LDSRCS, MSc, FFDRCSI
Specialist Oral Surgeon

2. Numb Chin Syndrome
Sensory Neuropathy (altered sensation and numbness) in the distribution of mental or inferior alveolar nerve.

3. Anatomy

4. Presentation Intermittent pain Progressive numbness
May lead to ulcer secondary to altered sensation
It can associate with pain and swelling

5. Aetiology Dental Causes Odontogenic Dental abscess Osteomyelitis
Benign tumours
Iatrogenic
Facial trauma
Wisdom teeth extraction
Sensory disruption after ID block injection
Orthognathic surgery
Implants
Mandibular surgeries
Orthodontic treatment
Pressure from dentures
Endodontic treatments

6. Systemic Causes
Aneurysms
Amyloidosis
Sickle cell anaemia
Syphilis
Sarcoidosis
Demyelinating disorder (Multiple Sclerosis)
Diabetes

7. Malignant Causes of NCS
Head and Neck Cancers
Breast Cancer
Prostate cancer
Thyroid cancer
Lung Cancer
Renal Tumours
Melanoma
Multiple Myeloma
others

8. Diagnosis History of present compliant Duration Presentation
Any previous traumatic history
Any previous dental treatment
Medical history
others

9. Clinical examination Extra oral examination
Mapping the area of neuropathy
Light touch
Pressure
Cold sensation.
Pin prick
Lymph node enlargement.

10. Intra Oral Examination
Mapping the area of altered sensation
Dental condition
Periodontal condition
Soft tissue
Hard tissue
Pin Prick
Touch sensation
Cold sensation

11. Investigations
Radiological
A-Periapical
B- OPG
CT scan
MRI

12. Case 1
66 years old female
Presented with intermittent pain of lower left Canine region of one week duration.
On examination, there was numbness of the affected area and the Canine was TTP.
Radiological examination, OPG and Periapical radiographs did not show any abnormalities
The patient was seen 2 weeks later and the area of numbness increased.
Patient was referred to Neurology Department and was diagnosed with metastatic renal cell carcinoma

13. Case 2
55 years old female presented with 4 days history of inflammatory lesion in LR3 with intermittent pain and numbness.
Extra oral examination the numbness extended to right infra orbital region, and right submandibular region and mental nerve distribution.
Intra oral examination, shows a ulcerated area of labial gingival opposite to LR3 .
Radiological examination, periapical and OPT did not show any abnormality.
Biopsy of the affected area confirmed the lesion to be inflammatory in origin.
The patient was referred to Neurology Department
MRI examination revealed an intra cranial arteriovenous malformation which was compressing on the trigeminal nerve root.
She was treated conservatively and the ulceration disappeared, the numbness stayed but less frequent.

14. Ulceration

15. Case 3
40 years old female presented with one week of pain involving posterior left mandible and one day history of numbness in the left mental nerve.
Extra oral examination revealed frank numbness in the distribution of mental nerve.
Intra oral examination, dental condition was good however there was dental caries in the lower left wisdom tooth.
Radiological examination, OPT confirmed periapical lesion associated with this tooth.
Tooth was extracted and the numbness disappeared.

16. Case 3

17. Case 4
47 year old female presented with history of numbness affecting lower left lip for few months.
Extra oral examination showed a well define area of numbness associated with distribution of mental nerve on the left side.
Intra oral examination showed fractured cusps of lower left 6&7.
Radiological examination, an OPT was taken and revealed an un-erupted and horizontally impacted wisdom tooth associated with a cystic lesion.
The tooth and the cyst were removed, few weeks later the numbness disappeared.

18. Case 4

19. Case 5
A 57 year old patient presented with progressive numbness of the right side of chin and lower lip. She had the numbness for four months.
Medical history, she had history of breast cancer which was treated with radiotherapy and chemotherapy 3 years ago. She was on medication for hypertension, thyroxin and intravenous biphosphonates 3 monthly infusion.
Intra oral examination showed a firm swelling in lower right second molar region with pus discharging, the adjacent teeth were not tender on percussion but were heavily restored.
Radiological examination OPT, revealed a patchy radiolucent area associated with apices of lower right second premolar and second molar

20. Case 5

21. Case 5
The teeth were extracted and the surrounded tissue and bone were biopsied the histopathology result did not show any secondary but a necrotic tissue.
The patient was diagnosed with bacterial osteomylitis secondary to osteradio -necrosis.

22. Discussion