|Sleep Apnea from an Anatomical and Developmental Perspective|
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Abfractions are covered and discussed in two articles I authored already posted on this website (in the section "Articles’). I would encourage you to read both articles to better understand my research on the topic. Many dental providers believe these ‘lesions’ are due to "improper tooth brushing habits" (Shafer, Hine Levy. A Textbook of Oral Pathology, Saunders, 1974, page 287) and/or chemical dissolution. Some patients are even scolded that they are brushing their teeth too hard. That would have been believable in the early 1900s when they used oyster shells and ashes in the toothpaste and used hard bristled brushes, but with today’s less abrasive dentifrices and very soft toothbrushes, I just do not know how ANYBODY can still believe that tooth brushing causes these lesions. These ‘abfractive’ lesions can be seen on a daily basis in every dental office in the USA today.
My hypothesis is that very few abfractions will be found in the teeth of prehistoric skulls. This is a pretty safe hypothesis in that this statement or position has already been researched (See slides A24 & A25 in the following presentation). The reason for this prediction is that during prehistoric times mothers had no choice except to breastfeed their babies. This is the same reason that malocclusions and dental caries are also very rare in prehistoric skulls. I even narrow my prediction as to the time frame when abfractions first appeared in larger numbers down to the last 200 years when the precursor to the modern baby bottle was first invented. This is described more in my articles and other presentations.
The following presentation is my clinical documentation or evidence on which I base my articles. All abfractive lesions in this presentation can be explained by the parameters discussed in my articles.
As you view the 3 parts of this presentation ask yourself:
1 - Could tooth brushing cause these lesions?
2 - Could juices or ‘chemicals’ that people normally ingest cause any of these lesions?
Exception: Bulemia and esophageal reflux can and do cause erosion of teeth, but the erosion these condition cause is mainly on the lingual surfaces of the teeth.
This presentation has been divided into 3 sections for easier downloading. You can print off or download this commentary along with the illustration sections as long as the information is used for educational purposes. Just click on the section title to open that section.
Section A: Introduction and history.(51 slides, 2.3MB)
Section B: Miscellaneous examples.(135 slides, 3.9MB)
Section C: Treatment options.(134 slides, 3.2MB)
Section A – Introduction and history
Slide # Comments:
A2 - Grippo was the first to use the term ‘abfraction’. The definition covers the significance of various forces that can be applied to a tooth.
A3 - Lee and Eakle have a nice illustration showing how the tooth can bend or flex and break off small pieces of tooth structure.
A4 - Bend a nail or coat hanger back and forth and they will break down in a similar manner.
A5 & A6 - Posterior teeth are designed to absorb forces down the central long axis of the tooth (Green arrow). The ligaments around the teeth act somewhat like shock absorbers. When damaging lateral forces are exerted on teeth (red arrows represent traumatic occlusal forces and the blue arrow represents traumatic forces from the tongue), the teeth can bend or flex at a fulcrum point, especially at the point of support which is usually around the gingival line. Lateral forces can be very damaging even if the forces are smaller or lighter than those going down the long axis (A7). Other consequences to these forces are discussed in my articles.
A8 - A14 - Patient EA presented with an abscessed tooth in 1993. It had no decay but it did have an exposure of the pulp chamber in the middle of an abfraction. Most of the abfraction was below the gum line. Tooth brushing could not have caused this abfraction. It is rare that an abscess is caused by an exposure like this in an abfraction. Note the unusual anatomic dimple just above the abfraction. This identifies it as the tooth in and out of the mouth. In A11, note that the tooth is in traumatic cusp-tip to cusp-tip occlusion (will be discussed further in a presentation on occlusion that will be place on this website in the near future) and the lateral tongue thrust is also exerting a strong lateral force on the tooth as well. Options of endodontics and crown were discussed with the patient, but patient preferred to have the tooth removed. In A12 you can see how much of the abfraction was below the gingiva.
A15 - This tooth was compared to a tooth at the Smithsonian with a similar shaped abfraction. Note the flat wear facet on the tooth from the Smithsonian. This occlusal wear indicates that tooth was in traumatic occlusion. The people I talked with at the Smithsonian had put that tooth aside as being unusual in that it had that notch. It was the only one at the Smithsonian they knew about when I was there evaluating skulls.
A16 - Do you think these abfractions were caused by brushing too hard? Note the different angulations of the abfractions. Tooth brushing could not have caused these abfractions.
A17 - One tooth actually fractured in half. A tooth fracturing because of an abfraction is quite rare. Treatment for this patient was limited due to medical challenges.
A18 - The cause of these abfractions was due to the excessively strong lateral forces generated by this powerful tongue thrust. Can’t you just visualize the teeth bending over from the forces of the tongue (similar to trees bending over in a strong wind storm)?
A19 - This picture demonstrated the beauty of natural forces wearing away the terrain over time. Abfractions are the results of forces over time as well.
A20 - The arm broke off this chair because I leaned on it one too many times (too many abnormal lateral forces).
A35 - Note the absence of a cuspid. I will discuss the significance of this more in my future presentation on occlusion.
A36 - Demonstrates microscopic cracks in enamel. These cracks can become more extensive over time and small chips can break off.
A44 - KEY ILLUSTRATION - Toothbrush abrasion looks somewhat like the edge of a wood saw blade with various size teeth edges. As GV Black noted, these lesions DO NOT LOOK LIKE THE LESIONS IN THE MOUTH - which are usually smoothed edged as demonstrated by the tooth on the right. This illustration alone should dispel any idea that these lesions are caused by tooth brushing!!!!
Section B - Examples of Abfractions
Abfractions can have many different shapes, sizes and locations. Following are some of the examples I have documented over time. While viewing them, ask yourself: Could these be due to tooth brushing or drinking acidic drinks or solutions?
If you have not already done so, I would recommend you read my 2 articles on abfractions (under ‘Articles’) for an explanation as to why I believe these occur. Most are self-explanatory, some are single illustrations and some cases have several illustrations that recommend that you look at following slides.
To me, ‘open spaces’ nearly always indicate the individual is a ‘tongue thruster’. ‘Tongue thrusting’ causes abnormal lateral forces on teeth and can contribute to the development of abfractions. Tongue thrusting is covered in more detail in other presentations and articles. A future presentation on occlusion will explain ‘traumatic occlusion’ in more detail.
B21 - Cuspid is too upright, bicuspid is at an angle.
B22 - How could tooth brushing cause this single lesion this far back in the mouth?
B23 to 26 - Lines of stress can even be seen in partials and dentures. Stress lines are difficult to see in the picture of the partials, but are quite evident in the models of the partials.
B40 to B48 - Compare the difference in the abfractions between 1993 and 1998. If does not show in the picture, but the centrals (#8 & 9) were in perfect contact alignment in 1993. The patient stated he hear a "pop" come from his teeth. Later he noticed his teeth started to shift. What had happen was the contact between 8 & 9 ‘slipped’ and made a ‘pop’ noise. The loss of the good interproximal contact resulted in the mal-aligned position of 8 & 9 as seen in B42. It was not until several years later that I noted his over developed mentalis (chin muscle). B47 is his mentalis at rest. B48 is a picture of the hyperactivity of his muscle during every ‘normal’ swallow. Try to get that much activity in your chin when you swallow and you will realize the powerful forces generated during his normal swallow. The powerful force generated the abnormal lateral forces that were responsible for his abfractions. As stated in B40, it took me a long time to determine where his abnormal forces were coming from. I have never seen anyone else with that strong of a mentalis muscle activity during a swallow.
B50 & 51 - What constitutes interferences and abnormal traumatic occlusion will be covered in a future presentation on occlusion.
B94 to B105 - This case is very similar to the case in Section A that was extracted in 1993 - except this case did not have an abscess and no teeth were extracted. Two restorations failed and had to be redone. Because of flexing, retention must usually be designed into the preparation or restoration can loosen and come out. Treatments will be covered more extensively in Section C.
B106 to 108 - A new abfraction has formed around an old previously restored abfraction. A new abfraction formed because the ‘reason or cause’ of the original abfractions was not addressed and resolved.
B109 & 110 - Interesting position and shape of an abfraction. Lingual (tongue side) abfractions are not as common as those on the buccal (cheek side of back teeth) or on the facial (lip side of front teeth). How could tooth brushing cause these lesions in this position?
B111 to 113 - This abfraction was caused by the lateral forces on the tooth from being in a traumatizing cross-bite malocclusion. The flat wear facet on the lingual cusp is an indicator of that traumatic occlusion or relationship.
B114 - It is a little difficult to see in the illustration, but this abfraction looked like a comma on its side.
Section C - Treatment Options for Abfractions
The primary treatment for abfractions is to try and remove the offending traumatic lateral force. For an isolated single tooth with an abfraction that is not caused by a tongue thrust, the simplest solution is to selectively reshape (equilibrate) the tooth (and/or the opposing tooth) so that the traumatic lateral force on the tooth is eliminated and a more tooth friendly force directed down the long axis of the tooth is generated (This will be explained in more detail in a future presentation on occlusion). It is possible to get immediate relief from sensitivity once the offending traumatic forces are removed from a tooth.
If the traumatic lateral force is due to a tongue thrust, then the person’s best treatment option would be to learn how to swallow correctly. This can be accomplished by referral to a person with special training in myofunctional therapy or orofacial myology. A link to the international association of people with that training is on this website as well as to the Coulson Institute in Denver which educates individuals with an interest in learning how to become an orofacial myologist.
Another possible option for a person with extensive abfractions, or for a person living in an area where orofacial myology is not available, is to wear an occlusal flat-planed hard splint which would support the teeth and minimize traumatic lateral forces.
Most illustrations in this section are self-explanatory.
C39 to 45 - This patient was a heavy clencher / bruxer. Forces in this mouth were extensive. I did not feel occlusal contacts could be refined and maintained, so a hard, flat-planed splint was fabricated. C44 shows point contacts of opposing cusp tips in centric and C45 shows excursive movements with cuspid rise / guidance.
C46 - I feel it is important to equilibrate / refine occlusal contacts when restorations are placed to minimize sensitivity and reduce risk of restoration failing in the future (due to flexing of the tooth and loss of restoration). I feel sensitivity can be caused (after the restoration is placed) when flexibility of the tooth is reduced or eliminated by the firmness / hardness of the restoration and the traumatic force on the tooth is re-directed elsewhere into the tooth.
C65 - Gingival grafts are an option to resolve some of the sensitivity and esthetic challenges of abfractions, but I still believe the ‘cause’ of the abfractions still needs to be addressed or failures will occur as in C66.
C73 - Money was a factor as to why this case was not done earlier.
C98 - Money was also a factor as to why this case was not done earlier. He was forced to make a commitment to proceed when the central fractured as illustrated in C101.
C101 & 102 - The teeth look like they are under a ‘flexing’ pressure similar to the flex in a deck of cards that are being shuffled.
C105 to 108 - The case was waxed up to make sure the case was designed to have cuspid rise and anterior guidance (Will be explained in more detail in future presentation on occlusion).
C109 to 112 - 5 of the 6 anterior teeth were prepared first. The one central was initially left unprepared and maintained as a ‘stop’ so as to better visualize clearance of the other prepared teeth.
IN SUMMARY:Abfractions are the result of traumatic lateral forces exerted on teeth due to malocclusions and / or tongue thrusting. Abfractions are not found in prehistoric times but are quite common in today’s contemporary society. This observation / hypothesis is due to lifestyles differences between the two time periods. These lifestyle differences include breastfeeding attitudes, bottle-feeding and pacifier use in contemporary times. In prehistoric time women had no choice other than to breastfeed their newborns. Modern habits of bottle-feeding and pacifier use are having a negative health impact on our society. I am excited that Norma, a patient of mine, will be doing her Master’s Thesis in Anthropology in the summer of 2005 on prehistoric skulls. I know her research will reconfirm this hypothesis.
IN CONCLUSION:Breastfeeding reduces the risk of both malocclusions and tongue thrusting. Any length of breastfeeding is better than not breastfeeding at all. It is extremely important that a newborn receive the mother’s colostrum or ‘first milk’. The longer an infant is breastfeed the better the chance the infant will develop a proper swallowing pattern. The swallowing action influences the position of the teeth in the dental arch and the height of the palate. The benefits of breastfeeding are negated by bottle-feeding, pacifier use, noxious infant habits and ankyloglossia (tongue-tie).
Please take the time to read the articles and other presentations on this website regarding my position that breastfeeding is the key to total health.
For Better Health!
Brian Palmer, DDS