Microscope Testimonial by Dr Rick Spencer


1. My Story

My wife and I graduated 23 years ago and within two years of graduation started to develop musculoskeletal symptoms. I have always felt this was due to my career as we have always been fit people and I personally have practiced yoga everyday for over 20 years. I soon learned from my local physiotherapist that the back and neck don't like bending for long periods.

a) The Literature: As early as 1965, reports have indicated that a third of practicing dentists had back problems that were related to their occupation (Fauchard Academy Poll, Dent Surv 41(9):69-70, 1965). Several articles about the dentist's posture during work had been published. These articles proposed a number of criteria for correct work posture such as: both feet flat on the floor, thighs parallel to the floor, back straight, head relatively erect, shoulders parallel to the floor, and elbows close to the sides and 2 inches below the patients mouth (JADA, Vol.107, December 1983, Page 937). In one study neck flexion of more than 15 and 30 degrees was performed for 97% and 82% of the work time, respectively with only a few short interruptions. When neck inclination exceeds 30%, endurance time is greatly decreased. Furthermore a neck flexion of more than 15 degrees is considered as harmful if held for more than 70% of the time (L. Finsen et al, applied ergonomics, volume 29, number 2, page 124. In an Australian survey, 82% of the dentists reported one or more of the following symptoms: 64% pain, 54% headaches, 19% pins and needles, 17% weakness, 13% numbness (E. D. Marshall et. al., Australian Dental Journal, 1997:42:(4):240-6.

b) About 15 years ago, I visited Dr. Dan Brener a specialist Prosthodontist in North Sydney. He developed severe symptoms soon after graduation and found the microscope solved his problem. Because he was doing specialist procedures I felt his procedures were not suitable for me in private practice but it had me thinking. Dr. Robin Hawthorne and Dr. Janis McAloon had started long before Dan as I later found out. Both have reported advantages with their posture.

c) In the meantime, my wife and I, were suffering with regular visits to chiropractors and physiotherapists. We had four children, the youngest of whom is now 6 years old. On several occasions I had to leave work at lunch due to severe pain. During these times I had some depression and was seriously thinking of a mid-life career change. However, dental skills were of no use in another profession and math teaching really wouldn't support my family. Then, June 2001 the CRA newsletter (enclosed) arrived. My nurse and I went to visit Dr. Janis McAloon at her practice in St. Leonards and using her scope, very much enjoyed looking at teeth with perfect posture. After many emails to Global Surgical and Dr. Rick Schmidt, I went to the USA and completed a 2-day course at The Newport Coast Oral Face Institute and also visited Dr. Rick Schmidt at his practice in Oregon. While in the USA, I talked personally to two dentists who had much worse back and neck problems than myself and were successfully back at work using the scope. Many more dentists have benefited in the USA and in some cases I have heard the disability insurance companies have paid for scopes. Global is working to make this more accepted. Some dentists pick up the skills required quickly and some more slowly, the biggest factor seeming to be their ability to use the dental mirror.

d) There were four brands of scope to choose from. Many dentists told me not to buy the Global. Reasons given were: it's flimsy, the optics are poor, and it looks cheap. I spent a lot of time researching all microscopes on the market as my whole family and career depended on making the right decision. I was fortunate to attend an international ophthalmic conference at Darling Harbour. To my surprise all the dental microscopes (except Global) were there, in other words the companies had simply put a dental label on their ophthalmic microscopes. These microscopes are designed to look in an eye hence : 

  1. they can only use halogen globes - more light damages the eye. 
  2. the field is the size of an eye. 
  3. they are made for very small movements. Some had motors but to move around the mouth they were too slow. 
  4. their stability was great since that is necessary for eye surgery.


On talking to colleagues I received a little encouragement but mostly negativity such as: it will terrify the children, it will slow you down, it's not possible for a general practitioner to use a scope for 95% of chair-side time. I said "If they are doing it in America, why can't we do it here?". I don't think they believed me.

I selected the Global Microscope for the following reasons :

  1. Small and light - much more pleasant for the patient and also for the dentist
  2. Wide field and low magnification possible - at 2x magnification I see all four quadrants and use this most of the time for my scaling and cleaning, rubberdam placement, local anaesthetics, impressions, matrixband and wedge placement,  occlusal adjustment, etc. It's the only scope that can achieve this by a long shot. The lowest magnification available in other brands is 3x. The beauty of low magnification is the wide field and no focusing problems because the depth of field is so great. My time taken to do a prophylaxis with the scope is the same as before except that I can see much better and I'm comfortable.
  3. Soft rubber eye cups - movement of the scope is simply achieved by moving one's head from side to side. Unlike ophthalmic scopes it's made to move freely however for intricate high magnification procedures it can be locked into position but probably is still not quite as stable as ophthalmic scopes. As a GP I don't need that option. Note all other scopes have hard rubber eye cups and if one attempts  to move the scope with the nose, it's painful. And I am constantly using this function to quickly move around.
  4. Incredible but expensive inclinable oculars - Whether you have a child or a large adult in the chair, the dentist needs to maintain his ergonomic posture by simply adjusting the oculars. This is easy to achieve. Global produce a fitting which is used in the USA which allows Zeiss users to use Global's superior oculars. Zeiss are just about to release a new scope especially for dentists which I have not seen. It apparently has a zoom objective which is another way of solving the above problem but with a foot control, motor, extra bulk and weight, and additional expense but I'm sure for some it could be good.
  5. Superior light source - which is essential for digital photography and a great bonus for working in the mouth. I use metal halide (four thousand kelvin) Zennon is available (the neurosurgeons use Zennon - that's five thousand kelvin) but it's costly to use. Halogen in all the ophthalmic microscopes is only about 1,500 Kelvin. Sunlight is 5,500 Kelvin.
  6. Retro-fitable - Global has made a pledge that all future improvements will fit on old machines. Already many improvements have been made eg. Zennon (good for endodontics) improved fibre-optic cable, etc.
  7. Many options available - You would be surprised at the options.

e) On returning I ordered my scope directly from Global which cost $62,000 including installation, a digital camera, a computer, and a wonderful digital/TV monitor which I ordered from INLINE Systems. Please note just yesterday I received email from Global informing me INLINE Systems are the new distributors for Global. Three months ago Jenny and I started using the scope. I installed a frasco (manikin) on the back of my dental chair and spent a full day going through my procedures with my nurse with the aid of a live screen from the digital camera which greatly helps my nurse. I have worked with my nurse for 15 years and she was happy to finally be able to see exactly what I was doing. Day 1 on patients - I didn't sleep well the night before even though I had practiced on the frasco by this stage 18 hours and done some prophys on my children. I was pleasantly surprised to achieve my goal of 95% chairtime micro-usage on the first day. It was so nice to be comfortable and the Global dental stool with arm rests was great. My thanks go to Dr. Rick Schmidt and Dr Martin Boudro at  who taught me some basic principles which were invaluable - see tricks of trade. Since then after one month I was back up to speed and with each day it feels more and more natural. Both my wife and I have experienced significantly less pain and felt confident enough to invest in a large property for our retirement which we can confidently pay for since our necks and backs are better. In the past 6 weeks I have taken over 500 digital photographs each photograph taking less than 15 seconds of chairtime.

2. Advantages of a Microscope

  • Perfect posture.Less musculoskeletal pain and damage to spine
  • The great equalizer - more than compensates for the failing eyesight of older dentists. I use the scope without my glasses.
  • Unparalleled vision and lighting - my scope has 6 steps of magnification i.e.. 2x, 3x, 5x, 9x, 12x, and 19x.
  • An ideal microscope is designed so that one is always looking into the distance - very healthy for the eyes.
  • Very easy, perfect [ with a good light source ],and quick digital photography.
  • Less collateral vision-around the field its all dark like a movie theatre and this creates less unwanted information and easier viewing.
  • Great practice builder-especially for some Women (patients) the scope creates more privacy and gives the patient more confidence.

3. Tricks of the Trade

  • Golden rules are  
    i) Always sit at 12 o'clock
    ii) Patient's head horizontal with objective lens parallel to floor except in rare circumstances 
  • Rubber dam helps
  • Very small mirror heads available from Hartzell Dental(usa) which are very useful for working in the hardest quadrant - the lower left. Also can be placed behind handpiece and sometimes can look under handpiece-I can search later for photos of this if you wish?
  • Stropco triplex addition made by Ultradent from Gunz.-the nurse using this combined with the very small mirror which is very easy to keep clean is a good ,fast combination-with the technique outlined mirror usage is quite high.
  • Fourhanded dentistry
  • Plastic lens covers and plastic bags in between each patient make infection control easy
  • Personally I use 
    - 2x - for rubberdam placement, impressions, local anaesthetics (I do blocks on the lower right with my loops), matrix band placement, prophylaxis, scaling, etc.
    - 5x - most high-speed drilling, root planing, placement of restorative materials.
    - 9x and 12x - especially finishing and detailing cosmetic work, crown preparations, checking root planing, root canal work, removing posts.
    - 19x - I cannot work at this magnification but find it very useful for intra-oral photography and checking restorations.
  • Don't cheat. If you can learn to use the scope without interruption it can actually be faster or as fast in most situations. However if one is switching between scope and loupes I believe it looses its ergonomic edge .
  • Denlite illuminated mirror I have found to be invaluable for subgingival scaling and root planing and tricky digital shots-eg.interproximal at 19x-I have photo if you want?
  • my oculars are under an aircoditioner and were fogging-a solution was to rig up a small suction line to the soft rubber eyecups-idea from Dr Rick Schmidt.