The worn dentition-Terminology

The following pages contain information which will help dental practitioners of all types to diagnose the reasons for wear patterns on their patients' teeth. It is based nearly exclusively on the experience of Dr. Thomas C. Abrahamsen, D.D.S., M.S, F.A.C.P. who has been making these observations since about 1972. Dr Abrahamsen has published his findings in a well regarded paper; The worn Dentition--pathognomonic patterns of abrasion and erosion. This paper is available online in .pdf format (Adobe reader, which can be downloaded free). Since Dr Abrahamsen has refused to allow me to use his images, I would suggest that the earnest reader download the paper and refer to the figure numbers that I have placed in the following text. I will attempt to populate this piece with images of my own over the next few years. Interested practitioners are encouraged to send appropriate images if they find this information helpful (see the email button in the right shared border).

Terminology

Dr Abrahamson has come to believe on the basis of studies carried out by WD Miller in 1917 and G. Sanges in 1975 that the term toothbrush abrasion is inaccurate and should be discarded in favor of the following terms:

Toothbrush recession: Studies have shown that the toothbrush, regardless of the stiffness of the bristles or the way the ends are shaped does NOT cause abrasion of the tooth structure. The toothbrush itself DOES cause injury to the gingiva, with consequent recession, and the extent of this injury is dependent on the stiffness of the bristles and the way the bristles are shaped at the tip. The most damage to the gingiva is caused by stiff bristles which are shaped with rough, sharp edges. The least recession is caused by soft bristles with milled, rounded ends.

Toothpaste Abrasion: Although the toothbrush does not damage the teeth by itself in spite of aggressive brushing, the addition of abrasive, in the form of toothpaste DOES abrade away tooth structure, a bit like a ragwheel with pumice on it will abrade away the acrylic on a denture. The ragwheel, by itself does little to the surface of the acrylic, but the addition of pumice will abrade the surface quickly. Furthermore, the coarseness of the pumice does not effect the final outcome. Even flour of pumice will abrade the denture away as surely as coarse pumice, given enough time and pressure.

Toothpaste Abuse: This term means nearly the same thing as toothpaste abrasion, defined above, but it requires some further explanation. Toothpaste abuse does NOT mean using too much toothpaste on the brush. It means using toothpaste in conjunction with very aggressive, prolonged, frequent, and hard brushing using a wide, back and fourth, "sawing" motion with the brush. This is most frequently done by patients on the occlusal and buccal surfaces of the teeth, and less aggressively on the lingual surfaces. It's a very common problem and is often engaged in by patients who do not like the color of their teeth. They mistakenly believe that aggressive brushing with toothpaste will whiten them. Instead, they wear away the white enamel allowing more yellow from the underlying dentin to show through.

The following terms are defined in fairly standard fashion except for the concept of attrition which now has an expanded definition to include both abrasion and erosion:

Attrition: Attrition is now defined as the pathologic wear of teeth from abrasion and erosion. Everyone wears down their teeth in one way or another during a lifetime, and thus everyone suffers at least some attrition.

Abrasion: Abrasion is defined as the pathologic wear of teeth from mechanical rubbing; either on occlusal surfaces from bruxing or from the misuse of toothpaste on virtually any surface exposed to toothbrush bristles and toothpaste.

Erosion: Erosion is defined as the pathologic wear of teeth from a chemical-dissolving process such as those cases in which stomach acid is regurgitated into the mouth in bulimia, or Acid Reflux Disease (formerly known as GERD). Erosion also happens because of acidic solutions and foods kept in the mouth for prolonged periods.

One further term needs special attention, because it is a highly diagnostic finding:

Cupping or Cratering: This diagnostic finding is one of the most obvious and easily discernable characteristics of erosive and abrasive attrition. When the practitioner sees cupping on molar cusp tips, its characteristics will go a long way toward helping with the diagnosis.
Cupping happens on the cusp tips of molars and premolars and incisal edges of incisors and canines. Cupping on molars has less to do with bruxing than with erosion caused by acids, while cupping on anterior teeth is more likely due to bruxing in older patients.

Diagnostic Models:

Doctor Abrahamson correctly notes that the diagnosis of all forms of attrition are facilitated by the use of hand articulated diagnostic models. In fact, all erosive and abrasive tooth stigmata are more easily seen on well made stone models, and the ability to hand articulate them has the added benefit of making it possible to inspect the occlusion from the lingual to see if occlusal wear on maxillary teeth actually coincides with the occlusal wear on the mandibular teeth. Many practitioners assume that all occlusal wear is from bruxing, but are surprised to see that the wear facets on opposing teeth do not coincide.

The five major causes of pathologic, noncarious tooth wear according to Abrahamsen

Abrasion:

Bruxism

Toothpaste Abuse

Erosion

Regurgitation

Soda Swishing (Coke Swishing, Pepsi Swishing, etc.)

Fruit Mulling

The following pages will examine each of these five causes of tooth wear and give the pathognomonic wear pattern associated with them. Images will follow in time, however in the meantime I refer you directly to the relevant figures in Dr. Abrahamsen's paper. I will give you the diagnostic features of each pattern of wear, as well as various questions you can ask the patient in order to confirm your diagnosis.

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