Phase II not controlled, open-label, prospective, single center clinical trial

• Determine changes in the xerostomia characteristics and discomfort degree by means of questionnaires addressed to the physician and subject of study.
• Determine the volume of submaxilar saliva without stimulation and with stimulation by sialometry (SL).
• Detect changes in volume, vascularization and fibrosis of submaxillary glands based on magnetic resonance imaging (MRI) with contrast.
• Detect changes of submaxillary gland functionalism based on Gammagraphy (GF).

Inclusion Criteria:

1. Patients from 18 to 75 years old of both sexes.
2. Biochemical analysis without significant alterations which could contraindicate the treatment.
3. Bilateral radiotherapy of the previous neck due to neoplasia in states T1-T2 and N0, N1 and N2a.
4. 2 years of follow-up without recurrence.
5. Reduction of salivation and hyposalivation, evaluated by an examination, flow rate or whole unstimulated saliva in the range of 0.05- 0.20 ml / min.
6. Grade 1-3 xerostomy as assessed by the grading scale.
7. The patient is able to understand the nature of the study.
8. Written informed consent of the patient

Exclusion Criteria:

1. Participation in another clinical trial in the 3 months prior to his/her inclusion.
2. Present infection (no infectious sign should be evidenced with repercussion on the evolution of the treated lesion).
3. Patients with positive serologies for HIV, lues and hepatitis with positive viral load.
4. History of cancer in the last 2 years. History of teratoma, adenocarcinoma derived from one of the salivary glands, lymphoma of the tonsils or some other lymphatic tissue or melanoma of pigmented cells of the oral mucosa.
5. Xerogenic medication in progress.
6. Other diseases of the salivary glands, for example, Sjögren's syndrome, sialolithiasis, etc.
7. Local infection.
8. Pregnancy or pregnancy planned within the next 2 years.
9. Breastfeeding.
10. Treatment with anticoagulants (not interruptible in MO or application).
11. Any other illness or condition that is grounds for exclusion for the investigator.