On Friday I had the fun experience of the "traditional" approach to making a (replacement) dental crown (multiple impressions, making + fitting of temporary crown etc) . And this was just the first visit. I still have the second visit to look forward to for the removal of the temporary crown and the fitting of the permanent crown.

On discussing this with our FD at work, she mentioned that her dentist had used a CNC milling machine to make a crown, and fitted in in the same visit. No temporary crown required. She seems happy, and the cost was not dissimilar to the traditional approach.

I found some blurb on the web here Dental Crown and Bridges from Harbour Landing Dental ( see New Advanced Materials and Fabrication section)

Any HC-er's have experience (comparative or otherwise) and / or care to comment.

I'd be interested in this approach, next time this required and welcome your feedback.

Grahame, I'll make a point of checking with my dentist Tuesday when I visit.

As a former "detail man" for a dental laboratory, the first question that immediately struck me was the occlusion area. This is where the word art applies in dental art. An impression does not give this information and a cookie cutter one size fits all approach. The materials used and how they fare over time would be another concern I would have. I recall offering semi precious and non precious metals as an alternative to gold. Both have proven over time that they are less durable and harder than gold which is not desirable.

FYI, unless the dentist takes terrible impressions or the dental lab fucks up, the second appointment is typically fast and easy.

if they start to come loose, bit of blu-tac will keep them going for another few years.

JB Weld will hold them longer than that.

JH13?

Back from my dentist. Apparently CNC milled crowns have been around 20 years or so and with good result. He has had 3 crack in his practice and several with chipping issues, but generally a solid product. He happens to prefer porcelain to gold crowns but thins the CNC ones are fine.

In his practice he chose not to buy the milling machine. His perspective is that he should concentrate on dentistry and the dental lab should concentrate on manufacturing crowns and bridges. Each an expert in their own field. He did say there is quite a learning curve to getting the process down right and that it took his brother (another dentist) a couple of years to get to the point that the crowns would be considered acceptable. You might want to be sure the person milling the crown has ample experience if you choose to have it done in the office.

Thanks for the info. My understanding (from my sources) was that they somehow managed to get a 3D Model / Image of the tooth / Crown,

(How? by scanning? combining multiple digital X-Rays? etc) , then tweak / edit it in software, then just press to the Go button on the milling machine (Hence the CNC part).

I can understand you'd want to adjust the the result for fit / occlusion - as you would with one cast from an impression, but its the application of rapid prototyping techniques to reduce the elapsed time for the whole process I find fascinating (and potentially to my benefit).

Apparently impressions will be taken digitally shortly, if not already. Send the impression to the lab in the morning and have the crown that afternoon. Don't think it would be any harder to generate a 3D image for casting crowns over milling them. I imagine that currently they are both using negative impressions.

cant some audiologist take impressions or your tooth?

...jhaudio introduces their latest creation - the jh in tooth monitor. for jaw jarring bass try the jh itm 21pro.

When I represented the dental labs one of them specialized in designer crowns. Might have a gold star, half moon, what ever. Most of my business out of Chicago and Detroit. A transmitter in a crown doesn't seem that far fetched.