The use of nailed horseshoe has unavoidable disadvantages compared to an unshod hoof. Out of the many disadvantages there are only three particular ones to be considered here:

1. Through the nail channels, which act as an entrance for rising bacteria, settlements of microorganisms are carried closer to the corium. This increases the danger of a purulent inflammation of the corium accompanied by pain and lameness. The danger increases through a direct or indirect nailprick.
   
   
   
   

2. The hoof mechanism is restricted when shod in the common way as shown impressively in the holographic deformation study under the use of ruby impulse lasers and by the computer based hoof reconstruction by HINTERHOFER 1997. The restriction of the hoof mechanism leads to a lesser blood flow especially to a restriction of the back flow of the blood from the foot.
   
   
    

3. The change of the tissue tension because of the shoeing enhances the development of vertical fissures of the hoof-wall reducing the function of the hoof considerably.
   
   
   It should be clarified by this experts opinion whether the three mentioned disadvantages are remedied by the nail-less shoe and what advantages can be achieved over the common shoeing system.
   
   
   In addition to that, advice should be given on how to proceed and what possible applicatons of the nailless horseshoe should be considered. For this experts opinion, a removed nail-less synthetic hoof shoe was given to me plus six natural horn samples as well as synthetic horn samples from all parts of the hoof. Also I took into consideration the holographic deformation measurement by Dr. Steinbichler laboratories dated October 23rd 1985.

In my expert opinion it can be stated that the disadvantages under 1. and 2. are excludes through the nailless synthetic hoof shoe. Conserning the disadvantage under 3. (tissue tension) an explanation is to be expected through a large scale computer based research study. According to HINTERHOFER 1997 the shoeing related limitation of the movement of the hoof positively correlates with the amount of tissue tension. Because of that an improvement through the synthetic shoe over the common horseshoe should at least be achieved.

The development of vertical fissures, because of increased tissue tension together with the danger of ground border splintering, is considerably lowered by this nail-less synthetic shoe. It does this because it acts like an outside skeleton protecting the natural parts of the hoof.

Advantages over the common shoeing method:

1. The bonding of the artificial horn and the natural horn, wich I have especially researched, is stronger than within the natural horn masses. This can readily be seen with the naked eye because most of the time the separation surface lies within the natural horn masses and seldom between artificial horn and natural horn but never within the artificial horn. Scanning electron-microscopic research proves this statement in an impressive way (look at the scanning electron-microscopic photos no. 1-7).
   In the natural horn, separation occur more frequently between the horn tubes and the horn between the horn tubes (see photos 4 & 5). The bonding of the natural horn and the artificial horn is so integrated that even naturally existing intercellular gaps, which are 0,3 micro metres wide, are filled with the artificial horn and thus disappear. (In extension of the arrow tips in all photos) Considering the fact that the connection between synthetic and natural horn occurs over a greater surface, one can expect a much better connection than with the conventional shoeing method where the connection only occurs at 6 points through the hoof nails.
   
   
   

2. The disintegration processes of the natural horn are delayed inside the synthetic horn horseshoe. Natural horn substances are construction materials with limited durability wich through the decaying processes turn into disintegrated horn losing it`s mechanical stability as well as it`s antibiotic barrier function. The disintegration processes are enhanced by the accelerated growth of bacteria under unfavourable environmental conditions like manure and urine. These unfavourable influences will be diminished or removed by the synthetic horn horseshoe and consequently the disintegration processes are slowed down. The synthetic horn is chemically inert which means no chemical transformation takes place but an integrated adhesive connection between the natural and the synthetic horn is achieved.
   (These exellent properties have been used for many decades in electron-microscopy to embed biological tissue in synthetic resin where it leads to an integrated connection but not to a chemical transformation.)
   
   
   

3. The polymerisation heat of 70° - 90°C acts positively because it is heat disinfecting.
   Thermal coagulation together with the loss of mechanical stability which occurs on the horn surface through conventional hot shoeing is, however, avoided because of comparatively low temperatures. Inside the synthetic horn horseshoe no micro-biotic deterioration processes could be observed through electron-microscopy analysis. With the common shoeing method, however, intensive disintegration of the horn caused by anaerobic bacteria can be readily observed with the scanning electron-microscope (especially with the "White line disease").

Advise for the mounting of the synthetic horn horseshoe  

1. Thorough cleaning of the natural horn with water and the chemical cleaning with aceton is advisable because aceton dissolves artificially added hoof-grease as well as the natural lipids of the intercellular putty. By freeing the natural horn from fat the adhesive properties are remarkably improved.
   
   
    

2. Coloured horn substances, found especially in the white line, which develop because of micro-biotic decaying processes, absolutely need to be removed and the remaining cavities disinfected with Iodine-ether to avoid the further growth of anaerobic bacteria under the protection of the synthetic horn (in the horn samples inspected by me this danger did not exist).
   
   
   
   

3. Rasping the external layer of the hoof and roughening of the gluing surface enhances the gluing properties.

Suggestions for broadening the application possibilities  

1. Through the genetically implied reduction in horn quality (brittle horn) the hoof nail does not find enough hold (known problem with the Lipizza Horses in the spanish Hofreitschule). Here the synthetic shoe offers itself as a good application.
   
   
   
   

2. Therapeutic application of the horseshoe, for instance at and after treatment of laminitis.
   Laminitis causes a loss in the barrier function of the white line against rising bacteria and because of that numerous horses are lost. A synthetic horn barrier against rising bacteria would be useful and affective. The synthetic horn horseshoe could be used as an orthopaedic horseshoe in case of hoof imbalances and when nesessary increase or relieve the pressure of certain hoof parts (e.g. elevation of the heels).

Prof. Dr. Klaus-D. Budras, 1. June 1998

Illust. 2 and 3:

 Left: Synthetic horn. Right: Natural horn-tubes.
 In between lies a grap free integrated connection.

Illust. 4, 5 and 6: 

The synthetic horn above the arrow tips is bonded without graps to the natural horn.
In the natural horn between the horn tubes and the horn between the tubes, separations can be clearly seen.

Illust. 7: 

Connections with and without gaps between the synthetic horn (left) and the natural horn (right).