Hello mam... Sensitivity is due to so many cause.. **Tooth cavity **cervical abrasion due to faulty tooth brushing... **Enamel erosion due to beverages... in this case you need to go for filling of the involved teeth and using simply sensitive tooth paste wont provide any relief.....

Go to dentist to know the cause  of sensitivity. Sensodyne is commercial have any paste like shy nm. Chew handfull of peanuts for 5-10 minutes atleast 2-3 times a day as they have high amount of minerals similar to antisensitivity paste and it will not harm untill you are allergic to them

First of all please don't take anything with extreme temperatures like icecream , tea , coffee and as you are telling sour items for a while and use desensitizer paste like sensodent kf, thermoseal RA,and please show to a dentist to know the root cause first it may be because of attrition , abrasion or erosion sometimes in cavities also such sensitivity can be experienced.accordingly doctor will advise you treatment.

You can use either thermoseal Ra or vantej toothpaste for your sensitivity. Apply on the affected area with the help of finger and leave for 2-3 minutes  and then brush normally.

Hello mam to reduce sensitivity use Thermoseal RA toothpaste ... Apply it over the tooth and brush after 3 minutes ... Within 2 to 3 days you will notice the change ... And cause of sensitivity is dentine exposure ... This toothpaste blocks the dentinal tubules

Please share details about the number of teeth and which teeth?