Sir, over the years I have noticed the number of articles dealing with the provision of implants as a treatment option. These articles mention the types of bone that can be present for implant therapy using a classification system used by Lekholm and Zarb1 labelling bone from D1-D4 types.

Not to be controversial but this type of classification is a misnomer and the teaching of this only prevents the clinician from truly understanding the complexity and importance of the recipient bone in relation to implant dentistry.

This can be easily evident on the examination of a cone beam computed tomography (CBCT) image which is commonly taken pre-operatively. As one that limits work to dental implants it has been rare to find an area of bone that is described and conforms perfectly to the Lekholm and Zarb bone classification.

I would advise colleagues to get a better understanding in examining and reading CBCTs in detail before implant surgery.2 It is far better to take into account the quality and quantity of the local bone and other specifics such as: the cortical thickness, the marrow spaces within, Hounsfield Units, the density of the spongy bone, the large trabecular radiolucencies etc. All of these factors can influence the primary stability and success rates of an implant and can be deduced pre-operatively, rather than labelling it into a specific class of bone post-operatively.

I would advise colleagues to be aware of the limitations in trying to classify the recipient bone into a specific group and to obtain further training in CBCTs as recommended by the British Society of Dental and Maxillofacial Radiology.3