Medit i500

I spoke with a sales rep from CAD-Ray recently.  The stats on the i500 are impressive.  It’s certainly the lowest priced intraoral scanner that provides color. No monthly data fees or per scan fees, but there is a yearly support fee after the first year. Bring your own laptop. CAD-Ray bundles with exocad for a complete chairside scan & design solution.



@ Yankee Dental

I was on the lookout for value-priced intraoral scanners at Yankee Dental, but came up short.  The most attractively priced — that I saw, where was Medit? — is the Aadva(tm) IOS from GC America.  This scanner had the fewest restrictions as far as ongoing fees and data ownership. The resulting mesh is probably OK from a point density standpoint, but did not look great on the big display at the booth. The scanner is best applied to scanning quadrants for single-tooth restoration.  The software is rudimentary, although updates are on the way. The blue light wand is one of the smaller ones I have seen. No tip to replace.

The Carestream C3600 (w/o color) was the next afforable option.  Carestream also takes the attitude that the customer owns the data. No concerns about scan quality here.

3M was present at Yankee Dental, but I didn’t see the True Definition on display.

iTero, 3Shape TRIOS, Planmeca, CEREC.  These are the big four and command the highest price.  They all have monthly fees, some more (iTero) and some less (Planmeca). You get what you pay for and according to your philosophy.  Want total control? Planmeca.  Want to have Align Tech clean up your scanning work? iTero. Want the best looking scanner? 3Shape TRIOS. Want the absolute best in German engineering? CEREC.

All systems have some type of connectivity, where the scans can be sent to participating dental labs. 3Shape and Planmeca have ways of sending that do not require a fee from the dental lab.

While a traditional impression might cost up to $60 (materials and shipment to the lab), I am told the real return-on-investment is seen in patient comfort and reduced chair-time.  The anecdotes are also piling up regarding final fit of the devices designed from digital impression. (The anecdotes are that the fits are great.)


Small Business Determination (SBD)

If your business had less than $100 million in revenue last year, then you qualify to be a “small business” in the eyes of the FDA. Simply file Form 3602! You’ll need to re-apply for each new fiscal year.  The review period is 60 calendar days, so plan ahead.

The FDA provides detailed guidance for US and foreign businesses here.


Unboxing a Formlabs Form 2 bite splint

I received a sample bite splint from Formlabs today.  This was made on the Form 2 with their Dental LT Clear Resin.  The material is bio-compatible and suitable for Class IIa medical devices. It needs some finish work.


another direct to consumer clear orthodontic aligner

UPDATED 2019-01-16 As seen on their website, Candid Co is printing the dental model and vacuum forming the tray. The post has been updated to reflect this.

I was recently directed to Candid Co‘s promotional content on Instagram. Smile Direct Club has been doing this for a couple years now.  Both are trying to out-align Align Technology.

Here are a few other key figures from Candid Co’s website:

  • $95 for an at-home impression kit and treatment plan
  • $1,900 or $80/month if approved for financing
  • A free set of retainers

Smile Direct Club’s pricing is also transparent:

  • $79 for an at-home impression kit or free digital impression at a SmileShop
  • $1,850 single payment or $250 down and $80/month for 24 months ($2,170 total)
  • $99 per retainer (upper and lower)

What is Invisalign going for? It’s not so clear (ahem), but many websites report $3,500-$8,500.  I think Align Technology would argue that the added cost of being treated in-person by your orthodontist is worth it.

#3dprint #dental


Align Technology’s use of 3D printing

I recently came across this 2017 article by TJ McCue: 3D Printing Moves Align Technology Toward $1.3 Billion In Sales It contains information useful to understanding Align Technology’s business model.  Here’s what I found.

Treatment Efficiency

8 million aligners a year for 540,000 cases is 14.8 aligners per case. They also report a cumulative 327 million aligners to 4.5 million patients or 72.7 aligners per case. Not sure what to do about that, but I expect they used to make a lot more per case then they do now.

Average Sales Price

At the time, Align estimated a US market of 10 million orthodontic cases a year, with 60% or 6 million cases where aligner treatment is indicated. They claimed 9% of those for 540,000 cases.

Figuring $1.283 billion in sales of Invisalign for 540,000 cases is an ASP of $2,167.  I don’t think this number has changed since then.


The author claims to have seen 50 to 60 machines.  The 3D Systems’ Figure 4 starts at $25,000. Material cost per part should be low, say $5. They must have more capacity than the 8 million part demand.  Let’s say they are at 80% of total machine usage.  Can one Figure 4 print 30 trays an hour? There must of been more machines than the author saw!

Whatever the cost structure, Align Technology has eye-popping results.


WordPress 5 on Heroku

I started off using mhoofman/wordpress-heroku. One gotcha from there is that the PostgreSQL plugin does not work.  Here’s what worked for me on my Ubuntu 18.10 desktop.


wget, git, and heroku-cli

$ sudo apt install git wget git
$ sudo snap install --classic heroku
Get WordPress

Download from, extract, move wp-config-sample.php to wp-config.php.

$ wget
$ tar xzvf latest.tar.gz
$ cd wordpress
$ mv wp-config-sample.php wp-config.php

I then made the following edits to wp-config.php  This allows all parameters to be set via ‘heroku config:set’.  The first block is used to configure the WP Offload Media Lite plugin.

define( 'AS3CF_SETTINGS', serialize( array(
    'provider' => 'aws',
    'access-key-id' => getenv('AWS_ACCESS_KEY_ID'),
    'secret-access-key' => getenv('AWS_SECRET_ACCESS_KEY'),
) ) );

Now get and parse the MySQL connection.

$url = parse_url(getenv('CLEARDB_DATABASE_URL'));

define('DB_NAME', trim($url['path'], '/'));
define('DB_USER', $url['user']);
define('DB_PASSWORD', $url['pass']);
define('DB_HOST', $url['host']);

Finally, define authentication keys and salts.

define('AUTH_KEY',         getenv('AUTH_KEY'));
define('SECURE_AUTH_KEY',  getenv('SECURE_AUTH_KEY'));
define('LOGGED_IN_KEY',    getenv('LOGGED_IN_KEY'));
define('NONCE_KEY',        getenv('NONCE_KEY'));
define('AUTH_SALT',        getenv('AUTH_SALT'));
define('LOGGED_IN_SALT',   getenv('LOGGED_IN_SALT'));
define('NONCE_SALT',       getenv('NONCE_SALT'));
Download and install plugins and themes.

I added the following plugins. Unpack each into the ‘/wp-content/plugins’ directory.

Do the same with desired theme, unpacking to ‘/wp-content/themes’.

Initialize git repository and create Heroku app

The base code, plugins, and themes are in place. wp-config.php created and modified.  Now initialize a git repository and create an App on

$ git init .
$ heroku create
Add MySQL and Sendgrid
$ heroku addons:create cleardb
$ heroku addons:create sendgrid
Now set those configuration variables

You’ll need your AWS Access Keys.

$ heroku config:set AWS_ACCESS_KEY_ID
$ heroku config:set AWS_SECRET_ACCESS_KEY

Authentication keys and salts must also be configured.  Do it one-by-one, or script it.

$ heroku config:set AUTH_KEY:a-strong-password
$ heroku config:set SECURE_AUTH_KEY:another-strong-password

Continue for all the keys and salts.

That’s it! Deploy and then configure your site and the plugins from WordPress itself.
$ git checkout -b production
$ git push heroku production:master

Point your web browser to Heroku’s App URL.  You should then get WordPress’s famous five-minute install. You can see my resulting code at terryg/wordpress-heroku.


Hello world!