Thank you for your question and welcome to Just Answer.
Your question touches on many points so I will tackle them one at a time, not in any particular order.
The Pronamel toothpaste does absolutely nothing to place back any tooth structure that you might have lost. This is deceiving marketing trying to sell another new and innovative product that doesn't really exist.
Also, the supplement you are taking might improve your bone density, but will not do anything to either replace any missing tooth structure or strengthen your teeth at all. All the enamel you will ever get came with your teeth when they erupted into your mouth as a child.
The description your give of the biting edges of your teeth indicate that they have become transparent (translucent) The orange pointed objects you see inside is the second layer of your tooth structure, the dentin layer. There are two possible explanations for this appearance.
1. You have worn the edges of these teeth thin by either grinding your teeth or simply by the way your teeth mesh together. If your lower teeth are crowded, then you might have a situation where by merely putting your teeth together or chewing, you are gradually wearing down the back surfaces of your front teeth and they are now so thin that you can see through them. If this is the case, the only way to replace the missing tooth structure is to have tooth colored filling material bonded in place to restore the teeth to their original thickness, or veneers or crowns depending on the severity of the tooth abrasion.. And, you should consider orthodontics to align your remaining teeth to prevent this from happening again.
2. Your tooth whitening product might have caused the translucency. These whitening products affect some peoples teeth in this way. If this just happened after using the trays then you should discontinue using this product and eventually the opaqueness ill return to your teeth. Expect it to take a few weeks.
3. I just thought if a third reason, If you eat a lot of acidic foods; lemons, tomatoes, carbonated drinks, grapefruit, or you have frequent episodes of vomiting, you might be dissolving your teeth away from the constant acid exposure. Again, the only way to replace the missing tooth structure is with some type of dental restoration
I hope this answers your question. If you would like to discuss this further or have any additional questions, please reply to my answer and I will get right back to you.
Sincerely, ***** ***** DDS