ANATOMY OF
MANDIBLE MALPOSTURE DISORDERS (MMD)
Harry Cooperman DDS*
Noboro Miura DDS**The masticatory apparatus is an essential body mechanical device intended to operate efficiently throughout the lifetime of the systemically healthy individual.
As primitive man began to remove from his food the grit, sand other abrasive substances found in his diet he deprived himself of a natural medical aid (attritional occlusion). The tooth-wear removed the deleterious effects of interlocking tooth cusps.
PRIMITIVE MOUTH
The deciduous teeth are considered first. In the primitive mouth, with an abrasive food diet, it is presumed that by the time the six year permanent molar is erupting, the occlusal surfaces of the deciduous teeth have undergone a slight modificatification
The six year molar has undergone some bite-correction modification. By the time the twelfth-year molar has come has erupted the sharp tooth cusps of all present teeth are worn by the primitive abrasive diet. By the end of the fifteenth year, the sharp pointed tooth cusps of all present teeth have been completely worn in a highly beneficial manner . The posterior teeth do not interlock. The mandible is permitted to develop forward until achievement of what nature apparently deems to be a perfect bite. There is an end-to-end bite for the anterior teeth, with all the posterior teeth meeting simultaneously.
All teeth are compatible and healthy and are generally retained throughout life in solid supporting bone structure. The mandibular condyles are in a perfect position required for excellent hearing.
CONTEMPORARY MOUTH
In the contemporary mouth, on the other hand, the teeth are being subjected to degenerative pressure. The maxillary dental arch is abnormally expanded. The mandibular arch is abnormally condensed. The bite is collapsed, with degenerative pressure being applied by the mandibular anterior teeth on their opponents. The condyles of the mandible are being jammed distally into a position that obstructs the inner-ear orifices. The synovial membrane (dental capsule) is projected anteriorly and the orifices of the inner ears collapsed to small elliptical openings.
By the end of the fifteenth year, the teeth are denied the benefits of natural bite correction. Raw-foods have been replaced by a soft pappy non-abrasive diet. Attrition of the teeth is not present. The teeth are completely incompatible. Moreover, the maxillary process and dental arch are still expanding. The mandibular process and dental arch continues expanding while at the same time the mandibular dental arch is condensing. The bite is closing, and cuspal interlock causes the pressure on the maxillary and mandibular teeth to become progressively worse. The condyles are beginning a potentially harmful distal movement toward the orifices of the inner ears.
In adult life the differences found in primitive and contemporary mouths are tragic.
In the primitive mouth, all teeth are compatible and healthy and are generally retained throughout life in solid supporting bone structure. The mandibular condyles are in a perfect position. In the contemporary mouth, on the other hand, the incompatible teeth are being subjected to degenerative pressures.
THE MYODONTIC MOUTH
Without doubt, the food-preparation habits of man significantly influence the development and maintenance of a sound chewing machine. Museum skulls studied and researched (1) of the raw-food and early cooked-food areas showed that the teeth are stronger and the general framework of the supporting bone structure is more massive. It seems anatomically and physiologically reasonable to assume that the masticatory muscles were also stronger, as well, in proportion to the relative massiveness of the skull jaws. Further, a dental comparison of these skulls derived from different areas demonstrated that the deeper man went into those periods the more pronounced his dental weakness became.
Nevertheless, there was substantial evidence as well that the sanitation habits of man also significantly influence the development and maintenance masticatory apparatus.
Study indicated that as man began to remove from his food the grit, sand, and other abrasives found in plain dirt he unwittingly deprived himself of a natural dental aid that had served him well by modifying his cuspal and dental planes thereby safeguarding his dentition from the deleterious effects of interlocking cusps. Most of the dentition examined had been subjected to natural correction and that this wear was obvious more significant in terms of the preservation of the dentition.
As man became civilized the dental conditions of the mouth became increasingly unsatisfactory in terms of (a) the natural shortening of tooth-crowns, (b) the removal of interlocking cusps, (c) the freedom granted the mandible during mastication, (d) the preservation of the dentition and (e) the reduction of masticatory strain (fibromyalgias and MMD.
In summary, the research indicated that during the uncivilized period of his existance man achieved his dental peak through vigorous employment of his masticatory dental mechanism against resistance which was highly beneficial because it abraded his teeth in a manner that tended to prevent occlusal lock and support his dental structures from degenerative stress. The research also indicated that as man developed his cooking and sanitation practices he lost many of the benefits of bite correction through natural wear and, in the process, lost much of his dental health as well.
* 777 Ferry Road / P-6
Doylestown, Pennsylvania, 18901 USA** 7-6-7 Ohjima, Kohto-Ku
Tokyo, Japan 13614 December 00