dry mouth or xerostomia may be caused due to a variety of disorders of salivary glands including irradiation. you need to first ascertain the cause first . loss of control over tongue may be due to nerve paralysis to the nerve supplying the tongue.

Hello and thank you for your question.

Dry mouth can be caused by an imbalance in amino acids and vitamins, change in salivary consistency, tumors, clogged salivary glands, mouth breathing, sjorgrens syndrome, fibromyalgia, nerve damage and weight fluctuations to name a few.

Chances are when you're deep in thought you breatht through your mouth with dries around your tongue and causes it to stick. You drool because your body is trying to produce more saliva.

Try biotene salivary products and chew xylitol gum.

If it persists, see your dentist for a proper examination.

Best wishes and good health.

Dr. Ward

Hello
Welcome to HCM
I think you are suffering from Xerostomia i.e. dry mouth associated with or without hyposalivation. Causes can be :-
-excessive mouth breathing
-hyposalivation
-Sjögren's syndrome
-poorly controlled diabetes
-anxiety
-drinking alcoholic beverages
-trauma to salivary gland
-dehydration
-chemotherapy & radiation therapy
-various medications including some antidepressants, amphetamines and antihistamines,

All these conditions lead to difficulty in mastication & speech & also produces halitosis & poor oral hygiene which further causes caries.

Treatment involves finding any correctable causes and removing them if possible. Sipping non-carbonated sugarless fluids frequently, chewing xylitol-containing gum,[4] and using a carboxymethyl cellulose saliva substitute may help. Pilocarpine may be prescribed to treat xerostomia.

Take Care
Regards
Dr.Neha

Hello & welcome,

Dry mouth is the condition when salivary glands produce less amount of saliva in the oral cavity following any underlying pathology or disease.

Tongue sticks to the floor of mouth just because of dryness in the oral cavity & there is not enough moisture to keep it working properly.

Dry mouth is associated with administration of certain Anti-Anxiety or Anti-histaminic drugs or it may be related to stress.

It is also seen in patients habitual of smoking or chewing tobacco.

Dry mouth should be immediately treated because it causes increased caries in teeth , Bad smelling mouth or Halitosis.

It is also related with Oral Sub-mucous fibrosis. If dry mouth persists for prolonged period, then periodontal health of the patient is compromised severely.

Drooping of saliva in thoughts is just because tongue is not in its proper place ( it is being stick to floor ) to obstruct the salivary flow out side from mouth.

So, visit your dentist for complete check up & get the treatment accordingly.

Take care.