Here's a cheap thing to try... it works for some, but you won't know until you try.
The ingredients...
- common household baking soda (sodium bicarbonate)
- hydrogen peroxide (a common first aid product, usually 3 % solution)
- water
I recommend making a solution of half water and half hydrogen peroxide. Don't make a bottle ahead of time. Make a fresh little "batch" each time you do this. You won't need much. Experiment with how much you'll need but you may be able to get away with as little as a teaspoonful (5 ml) each of both hydrogen peroxide and water.
Next, place a small amount of baking soda in your palm. Again, you'll have to experiment with what will be a good amount for you, but I'm talking about a small quarter sized amount to start and then you can always add more.
Next, pour some of your hydrogen peroxide-water solution onto the baking soda in your palm. You are going to be mixing a little paste in your palm with your toothbrush. So experiment with the amount of each until you get something you are comfortable working with. Some like a thicker more "pasty" substance. Some like a more watery substance.
As you mix these all together, a chemical reaction is occurring. There will be a "foaming" and the release of bubbles. That is to be expected. Oxygen is being produced.
Use that substance to brush your teeth. Pay attention also to brushing your gums and tongue as well. Do not scrub any harder than you normally would, but do try to cover as much area as possible.
I like this home-made product for these reasons...
The baking soda "particles" act as a scrub and clean the tar and nicotine by-products that adhere to your teeth and gums.
The production of oxygen is beneficial because bad breath can also be a product of bacteria that are considered to be anaerobes, that is, they do not need oxygen to live. Forcing oxygen on them is like "death" to them. It forces these bacteria to cease to produce an odor causing sulfur gas and forces the production of an odorless sulfate gas (when sulfur combines with oxygen).
Peroxide also has a mild bleaching effect, so a very gradual whitening of the teeth can be caused.
CAUTION: DO NOT SWALLOW. Hydrogen peroxide is not ever meant to be taken internally. So be sure to spit and rinse after brushing. Once again; DO NOT SWALLOW.
Note: Since no fluoride is in this mixture, there is no cavity protection. Do also use regular fluoride toothpaste as recommended by your dentist. I am only recommending the above as a possible cleansing to alleviate smoker's breath.