Numb chin syndrome in Ewing sarcoma

Numb chin syndrome: What all oral health care professionals should know

BACKGROUND

Numb chin syndrome (NCS) is a rare sensory neuropathy involving the mental nerve. Symptoms of NCS are often overlooked because of their apparent innocent nature; however, owing to the frequent association of NCS with malignancies, the opposite should be the rule. Oral health care professionals may be the first to encounter patients with NCS and should be aware of its clinical characteristics in an effort to decrease patient morbidity and mortality.

TYPES OF STUDIES REVIEWED

A search in PubMed (MEDLINE) and the Cochrane Library was performed using the terms numb chin syndrome, numb chin, mental neuropathy, mental nerve neuropathy, and malignant mental nerve neuropathy, yielding 2,374 studies. After inclusion and exclusion criteria were applied, 102 studies remained. Descriptive statistics were performed, analyzing the etiology responsible for NCS, characteristics of NCS including associated symptoms, unilateral or bilateral nature, and information on professionals visited and examinations requested to make a diagnosis.

RESULTS

NCS was associated with malignancy in 29% through 53% of the published cases. Twenty-eight percent of patients initially consulted an oral health care professional with the symptom of a numb chin. Patients more likely to have NCS were those from the ages of 61 through 70 years; 74% were unilateral; and the most common symptoms reported were numbness (100%), paresthesia (18%), and pain (17%). Forty-seven percent of the NCS cases were associated with a recurrent malignancy, and the most prevalent associated diagnoses were breast cancer (32%) and lymphoma and leukemia (24%).

CONCLUSIONS

Oral health care professionals should be aware of the characteristics of NCS as they may be the first health care providers consulted for these symptoms.

PRACTICAL IMPLICATIONS

A thorough medical and dental history as well as a complete cranial nerve screening should be performed on all patients, especially those with numbness, as this may prevent misdiagnosis and allow a timely referral and a substantial improvement of treatment course and prognosis.

Numb Chin Syndrome

"Numb chin syndrome" (NCS) refers to new-onset numbness of the lower lip and chin within the distribution of the mental or inferior alveolar nerves. While this focal numbness may be downplayed or even overlooked by patients and clinicians, in the right clinical scenario this may be the presenting symptom of an underlying malignancy. In the absence of any obvious, temporally related dental cause, there are certain conditions that clinicians should consider including orofacial and systemic malignancies as well as several inflammatory disorders. Thorough diagnostic evaluation should always be performed when no clear cause is evident. This paper will discuss the differential, recommended evaluations, and the prognosis, for a patient presenting with NCS.

Numb chin syndrome as initial manifestation in a child with acute lymphoblastic leukemia

Numb chin syndrome (NCS) describes the affection of the inferior alveolar nerve and is a purely sensory neuropathy. Its symptoms include numbness of the skin of the chin, the lip and the gingival mucosa. Mostly seen in adults, it has rarely been described in children. We report on an 11-year-old male who presented with NCS as initial manifestation of acute lymphoblastic leukemia of B-cell type.