Department of Companion Animal Clinical Studies, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa
Beak abnormalities and trauma can be challenging entities to deal with.1 Not only is the anatomy often foreign for the general practitioner, but depending on the size of the animal the space to work in is very small and the biting forces acting on the beaks can be immense.2
The availability of dental materials to the practitioner and knowledge of how to use them can greatly improve the options available to these patients in the future.3,4
The bird's beak (rhamphotheca) consists of a lower beak (gnathotheca) and the upper beak (rhinotheca). The rhamphotheca consists of keratin and grows from a germinal layer that covers the underlying jaw bones. Interesting to note is that the rhamphotheca does not consist of only one type of keratin, but that the tip and sides have a harder keratin (tomia) compared to the rest of the beak.5 Beaks are adapted for a specific diet, hence the varied shapes and sizes.
The beak is supported by several bones and several joints attach it to the skull, the detail of which is beyond the scope of this discussion but can be found elsewhere.5
Causes of Beak Abnormalities
The causes of beak abnormalities are varied but can broadly be classified into trauma, nutritional, disease, and congenital.1,5,6
Fighting amongst psittacines is one of the most common traumatic events that may lead to beak fractures, luxations, or even avulsions. Powerlines is a hazard for most hunting birds and may cause fractures, partial or even complete avulsions of beaks. Hunting of birds, legally or illegally, has the potential to leave some animals maimed. The most famous case is Beauty, a bold eagle in Alaska.7
Softening and flacking of the beak can be caused by a deficiency in vitamin A. Beta carotene is a precursor to vitamin A and is very important in the keratin formation of beaks, feathers and nails.
Feeding of young chicks by a right- or left-handed person can have the effect that the crop needle/tube always gets placed from one side and this may cause deviation of the beak.
Psittacine bird and feather disease (PBFD) is caused by a circovirus that affects many parrots, especially cockatoos. It may cause beak thickening, elongation, ulceration, and fractures.
Knemidocoptes mites cause inflammation and proliferation of the beak. This is commonly seen in the budgerigar.
This is a very rare cause of beak abnormalities, but squamous cell carcinoma and fibrosarcoma have been reported affecting the rhamphotheca.
Liver disease leads to interference with amino acid metabolism and glycine especially is important in keratin formation. Overgrowth of the beak is often attributable to liver disease and should always be evaluated when birds with overgrown beaks are presented.
Scissor beak, mandibular prognathia or maxillary brachygnathia are all reported in especially handfed macaws and cockatoos, but it may affect many different parrot species. The cause is often not determined, but timeous treatment can correct the defects predictably in a short period of time.
Review of Treatment Options to Correct Beak Deformities
Several cases of beak treatment options will be demonstrated by suitable examples.
Case 1: Duck with # mandibula
A young duck was presented with a complete fracture in the mid-mandible. The procedure of repair with a dental composite is demonstrated.
Case 2: Macaw with # maxilla
A macaw that was attacked by another macaw suffered several fractures of the maxilla and rhinotheca. The fracture repair combining threaded parapulpal pins (TMS Link - Coltene) with the dental composite.
Case 3: Eclectus with congenital beak deformity
A young eclectus chick was presented with a maxillary brachygnathia. Initial treatment with beak trimming and the threaded pin/composite technique did not give acceptable results. This case was then approached with the use of a prosthesis that gave superior results.
Case 4: Goose with beak deformity
A young goose with deviation of its mandible was presented. The cause of the deviation was not known, but thought to be congenital. Due to the poor surface holding ability for a composite splint, a prosthesis was manufactured for this animal.
Case 5: Blue crane with beak deformity
A blue crane with a scissor beak of unknown etiology was presented. Initially, a composite ramp was attempted to correct the deviation and there was some success with this technique. Due to the fact that this was already an adult animal and that the cause of treatment was going to be much longer, a prosthesis approach was also adopted in this case with acceptable results.
Beak repair in birds has progressed from near-exclusive orthopaedic treatments a decade or two ago, to treatments incorporating several extraoral techniques utilising dental materials. Treating these fractures or deformities can be very rewarding; however, a detailed examination and diagnosis should precede any intervention to correct a deformity. Where nutritional, infectious, neoplastic, or systemic disease is present, this should primarily be addressed before the beak repair/alteration is attempted. Beak repair/alteration patients should also be appropriately monitored in order to maintain adequate pain control and make sure these patients do not become anorexic.
1. Wheler CL. Orthopedic conditions of the avian head. The Veterinary Clinics of North America Exotic Animal Practice. 2002;5(1):83–95, vi.
2. Fecchio RS, Seki Y, Bodde SG, Gomes MS, Kolososki J, Rossi JL, et al. Mechanical behavior of prosthesis in Toucan beak (Ramphastos toco). Materials Science and Engineering C. 2010;30:460–464.
3. Schnellbacher RW, Stevens AG, Mitchell MA, Beaufrere H, Tully TN. Use of a dental composite to correct beak deviation in psittacine species. Journal of Exotic Pet Medicine. 2010;19(4):290–297.
4. Frye FL. Prostheses enhance quality of life. Veterinary Medicine for the Small Animal Clinician. 1984;79:931–935.
5. Olsen GH. Oral biology and beak disorders of birds. The Veterinary Clinics of North America Exotic Animal Practice. 2003;6(3):505–521, vi.
6. Wade L. The parrot beak 2013 [cited 2014]. Available from: www.birdchannel.com/bird-diet-and-health/bird-care/the-bird-beak.aspx.
7. Zimmerman J. Injured bald eagle gets new 3-D printed beak 2012 . Available from: http://grist.org/list/injured-bald-eagle-gets-new-3-d-printed-beak/.