[Herbnerd]

MariaGarcia said:

Thanks a lot. As a student, all this is a valuable information, although it discourages me because I don’t have access to that kind of ingredients, neither to the appropriate tests, so it seems quite useless to experiment with toothpastes at home 

I don’t mean to discourage you, just provide you with information. If you are manufacturing for home use, do carry on if that is what you want to do.

If you want to develop for sale, there will be more work to do and providing safety trials will be part of that process.

As for testing costs - when I started at the company I am with now, there was no budget set aside for trials and no consideration for testing costs. They were shocked when I put together scale-up trial and testing costs of around $250,000 - but this was for almost two dozen products and 500 kg scale up trials for each along with RDA/PCR, stability, PET, Fluoride stability, free & total fluoride assay, fluoride uptake etc etc etc and didn’t include any re-trials because my manager insisted on running trials before we were ready.

[Herbnerd]

MariaGarcia said:

I understand. But if all this is so vague, how do you formulate a prototype toothpaste for a specific purpose? I mean, you are looking for some characteristics and you need to have an idea about what ingredients to use and in what proportion to get closer to the result you are looking for, and then do the necessary tests to check if the product is correct and/or work on the corrections. There must be some general rules… Or is it just the supplier of each material who tells you the proper dosage?

Formulation to specific purposes is far easier with dental grade silicon dioxides, such as the zeodent range from Evonik.

You can use the different grades for tooth whitening (High abrasives), to very gentle abrasion suitable for kids.

Their website (although I have found it to be faulty and they are correcting this) allows you to target a specific RDA using specific grades of silicon dioxide; however, their mixing model  on the website doesn’t allow you to mix different silicon dioxide. But if you deal with their innovation lab, they have different mixing modeling software that allows great targeted RDA.

Other abrasives, such as calcium carbonate or calcium phosphate or even sodium bicarbonate, are much less flexible in formulating to a specific PCR/RDA - and there is a fair amount of trial and error.

That said, Omya have a great range of dental grade calcium carbonates, also Specialty Minerals. Omya probably has better information sheets and grades.

[Herbnerd]

MariaGarcia said:

chemicalmatt said:

I cannot fathom how kaolin would be a better and less expensive abrasive than dicalcium phosphate, which was used traditionally in these dentrifices. Is there an issue using phosphates in E.U.? If you are to “put clay in the mouth” then try out the perlites from Imerys, a Spanish company. More abrasive than kaolin.

 There were exceptions (e.g., refined kaolin clay) that had high PCR scores and low RDA values, resulting in higher CEI values“:

CEI is just a calculation based on PCR/RDA (CEI = (RDA + PCR – 50) ÷ RDA)

- it gives and indication of cleaning efficiency. However talking with others in the industry, it seems there should be greater weight on the PCR rather than RDA - you want your teeth to be clean but not necessarily abraded away to the dentine.

[Herbnerd]

MariaGarcia said:

Thanks a lot for your answer, Herbnerd. I really apreciate it  <3 .

I asked this because, according to what I studied, the amount of abrasives (in addition to the particle size, of course) in a paste determines its level of abrasiveness, and depending on the orientation for the formulation that I had, these should be added in 15-50%, in depending on the degree of abrasiveness desired. In a solid toothpaste the proportion of abrasive is much higher, and I was looking for a way to reduce it…

I feel a bit embarrassed now because I really don’t know the particle size of these two abrasives . Here in Spain, I suppose it’s the same in other countries, it is difficult for small formulators to access different qualities or granulometries of a material. It is sometimes difficult to get such accurate information from retailers.

I made a 100g sample batch, using A.Vogel brand’s kaolin, because it is the finest and purest I have been able to access, and calcium carbonate that the pharmacy on my street supplied me (they have been making pharmaceutical products since 1719 in their back room lab). I’ve just sent them an inquiry about the particle size of their carbonate, I hope they can answer me…

In my sample I did not feel that the product was too abrasive, my teeth felt polished, and I felt a less gritty sensation than using, for example, Colgate Cavity Protection Caries (I can’t find how it is valued by the RDA), although I know that is a subjective perception, and I’s still concerned by the high amount of abrasives…

Thanks again

There are a number of different issues here. Proportion of abrasives does not necessarily mean something is more abrasive or less abrasive. I can use 25% of a certain grade of silicon dioxide and it will form a nice gel but will not clean teeth, I can use 6% of one silicon dioxide grade and get the same abrasivity as using 20% of another grade. But even within various grades of silicon dioxide, the amount you use can affect the abrasivity - the same grade could provide different RDA/PCR values depending on the quantity used.

Even something like silica - you can have grades of silica that provide a sensory (gritty) aspect to the paste - and still have a low RDA.

Abrasivity is governed by many aspects - the material you use, the particle size, the hardness of the material when compared against enamel. Even the time after eating when you brush.

Talking with raw material suppliers and even testing laboratories, the tooth samples they use to test abrasivity can also affect results - certain cow breeds (they tend to use bovine teeth for testing unless your request human teeth), the area in which they were raised and even the year they were born can skew results.

One of the tasks I have to do shortly is cost optomisation on the calcium carbonate - precipitated vs ground calcium carbonate. Even with precipitated calcium carbonate, there is no direct swap - crystal shape is also affecting not only abrasivity but also the viscosity and structure of the toothpaste (not necessarily and issue with a tooth powder). Most suppliers would not be able to tell you the aragonite to calcite ratio (in fact I have only found one supplier to states aragonite content.

Personally, I wouldn’t rely on a particular material until you have tested the finished product - especially if you intend to sell the finished product

[Herbnerd]

Are you using lakes or dyes? Lake colour by dispersion but are insoluble in water but will disperse through powders or are suspended in creams. Lakes will separate out in water. Dyes will dissolve into the water phase

[Herbnerd]

Re calcium carbonate & kaolin - do you know the particle size of these two materials since these will be your two abrasives? 
I currently use two different grades of calcium carbonate - one at 2 µm and another at 9 µm. The 2 µm is just a polishing grade, whereas the 9 µm is far more abrasive (currently out toothpastes are around the 120 RDA/90 PCR).

Clays such as kaolin may not be as fine as you think - some have quite harsh particles in them - one of our toothpaste is around 150 RDA which is classified as harmful (some whitening toothpaste are as high as 250 RDA).

Adding Xanthan gum and MCC will also help with tableting - I can’t see MCC having much effect on the abrasivity though - and it might be hard finding any data to support the abrasivity of MCC.

If you need to test your product, Indianan Dental School (Oral Health Research Institute) will be the way to go to test RDA/PCR.

[Herbnerd]

From memory, a number of essential oils will weep out from the wax base over time.  I understand from the couple of candlemakers I know this is the reason they buy perfumes specifically for candles.

[Herbnerd]

1Armand2 said:

toothpaste formula is simple!

toothpaste is simple - but fluoride stability in a calcium carbonate paste isn’t so straightforward.

[Herbnerd]

Devesh327 said:

Thank you Herbnerd. I have studied Menthyl Lactate, However, It is almost Rs.8500 per Kilo which is very expensive. I need a cheaper compound. 

Not sure what you want to pay but check https://dir.indiamart.com/impcat/menthyl-lactate.html

You might find something in your price range.

[Herbnerd]

I had to do some digging on a formula I was working on where they wanted the cooling effect of menthol without the smell.

Menthyl Lactate and a few other Menthyl compounds are available. Check out the Frescolat range from Symrise:

https://www.symselect.com/cooling_warming

[Herbnerd]

There is no difference between Ascorbic Acid and L-Ascorbic acid.

This molecule exists in two enantiomers. The L-from is Ascorbic acid; the D-form is called erythorbic acid. 

[Herbnerd]

Yep - Feel free to contact me. Just let me know what specifications you require.

[Herbnerd]

Pattsi said:

LOVE is pretty normal to me, if someone declare SEX or ORGASM that would be more exciting.

@Pa@Pattsi Does Salmon sperm count? (well, maybe not for LOVE!)

[Herbnerd]

Sheep placenta is a common ingredient used in cosmetic products from New Zealand. The Chinese love that stuff.

Though I did hear it was a popular product amongst African Americans, until the residual hormones present in placenta started interrupting their cycles.

Sheep placenta is a by-product of the slaughterhouse - along with stabilised amniotic fluid (Yes, this is real too) and sometimes the whole uterus along with placenta and lamb is used to produce the “extract”.

One job I had, and sadly this is true, was to develop a range of placenta beverages for the Asian market. You cannot begin to imagine how disgusting the smell was. People who worked with me at the time certainly have never forgotten.

[Herbnerd]

You would probably need to buy a glass muller for an artists supply shop and grind the pigments yourself in a liquid base. Artists tend to use oils, IPA may evaporate too quickly to do this effectively. 

So, may be better to buy pre-dispersed pigments.

[Herbnerd]

Epsom salts are insoluble in oils and waxes. You won’t be able to do it.

Only possible way would be to dissolve the epsom salts into water first - and then emulsify into the waxes. But you are looking at around 20-25% epsom salts in the water phase.

[Herbnerd]

Simplest thing would be to dissolve the menthol crystals into the Eucalyptus and Orange oils first, once dissolved, you can mix into the fractionated coconut oil (I assume you are referring to MCT/Capric-caprylic acid?)

Highly saturated oils tend not to go rancid; however, you could add some vitamin E or rosmarinic acid to it.

[Herbnerd]

Currently formulating toothpaste for an international brand. Feel free to drop me a line with your brief.

[Herbnerd]

Capric/Caprylic acid triglycerides (often sold as medium chain triglycerides) are perfectly edible. 

You find this is popular amongst keto devotees for weight-loss

[Herbnerd]

@MapX

For work, I have a kitchenaid mixer to do all my development work. I do have access vintage vacuum mixer to do the de-aeration, and I fill the toothpaste tubes with a chef’s piping bag and cream nozzle; and seal the tubes with a hair straightener!

A company with $10 billion of sales can’t stump up $15K on some basic lab equipment!

It can be done on a budget if you need to!

[Herbnerd]

@ketchito Thank you. This is what I needed to hear. Greatly appreciated.

[Herbnerd]

I’m working on this at the moment, including the Sorbosil TC15, though I am swapping (owing to work wanting me to reduce all our single ingredient suppliers) to Evonik Zeodent 168 as the viscosity forming part and Zeodent 115 as the abrasive.
On their own, the TC145 or Zeodent 168 isn’t enough to form a gel. I have used Sodium CMC (Cekol 2000) at 0.5% to further increase the gel.

I’ve not tried with carbopol - you need to neutralise this to get the full gelling effect, and not sure how this would do at more alkali pH. I have tried dispersing this in glycerol previously, when you add the water it thickens up nicely.

Translucency is the bit I am struggling with. You need to match the refractive index of the liquid (Sorbitol, glycerol, water) with the refractive index of the various silicon dioxides - and you need to mix in a vacuum to de-aerate otherwise it is just as white as if you has used calcium carbonate.

[Herbnerd]

I suspect you are dropping the hyaluronic acid below the isoelectric point and precipitating the proteins.

For general stability, you ideally need a pH of between 3.6-4.2

[Herbnerd]

Personally I do everything in Excell. I set up a database tab with all the ingredients and parameters I need (pack size, INCI, trade name, costs etc) and use a formulation template to do the formulation and costing using index-match-match.

[Herbnerd]

Yep, as stated by others, it is a combination of low water activity and low pH. T

The combination of sugar and glycerol, lowers the water activity.