Genetic Component of Ortho and TMD: Mother-Daughter Comparison

By Clayton A. Chan, D.D.S.

“The ultimate responsibility of the orthodontic therapist is to treat all three components of the stomatognathic system to create an environment for synergistic function of the teeth, temporomandibular joints and the neuromuscular system.  Successful orthodontic treatment is predicated on eliminating adverse muscles forces on teeth that have been positioned in a zone of neutralizing muscle forces.” – Robert Jankelson, DDS

Growth and Developement: An Orthopedic Concept to Dental Occlusion

The occlusion of the deciduous dentition actually serves as the key that controls the engrammed muscular patterns for further growth and development of the mandible and maxilla throughout life.  As long as there is no retention of noxious habits, no chronic upper respiratory allergies, no chronic obstructing tonsils or adenoids, and no genetic orofacial deformities that would displace the tongue, lips, and cheeks, creating abnormal force vectors against the palate and erupting dentition, a normalized growth and development of the dentition, orofacial morphology and cervical head posture will occur.

Mother and Daughter Comparison of Dental Occlusion

Note the genetic similarities of mother and daughters teeth arrange, shape and occlusal form. (First two pictures is of mother with teeth together before orthotic treatment and after with lower orthotic treatment for her TMD problems).  Both groups of pictures  show deep bite tendency, Class II division 2 dental and Class II skeletal relationships.  Both have gummy smile tendency.

Mother experiences numerous musculoskeletal occlusal signs and TMD symptoms.  Lower removable orthotic was implemented to eliminate hyper active muscle tension, headaches and jaw problems.  Note the increased vertical as well as corrected antero-posterior dimension of the posterior occlusion.  After TMD symptoms are stabilized and proven to be symptomatic free, orthodontic/orthopedic techniques can be conservatively implemented to vertically grow and develop the lower arch using the orthotic as the “Orthopedic Maxtrix” to grow and  develop the  occlusion to the Optimized Bite position.

12 year old daughter shows genetic similarities as mothers teeth (above).  Early orthodontic intervention was implemented using a combination of functional appliances and fixed orthodontics to orthopedically verticalize the lower arch to contact the upper arch after upper arch leveling and aligning.  Daughter does not experience any TMD muscle or occlusal signs and symptoms.  Patient does not wear retainers to maintain her bite position.  The orthodontics was completed following Optimized Bite protocols and principles.

Conclusion:

Early orthodontic/orthopedic intervention should be a key consideration for all parents and dentists when recognizing the early occlusal signs and abnormal intra oral growth and development problems present themselves in every dental office.  By early detection and diagnosis the ills of TMD craniofacial muscle pain problems can be avoided and effectively treatment in the early stages of life so that unnecessary restorative, TMD and late stage ortho correction can be avoided in the adult stages of life.


© 2009 Clayton A. Chan, DDS. All Rights Reserved.

The Leader in Neuromuscular Dentistry

Orthodontic risk factors for temporomandibular disorders (TMD). I: Premolar extractions.

Krenmenack, CR, Kinser, DD, Harman, HA, Menard, CC, Jakobsen, JR: Orthodontic risk factors for temporomandibular disorders (TMD). I: Premolar extractions.Am J Orthod Dentofacial Orthop. 1992 Jan:101(1):13-20.

Abstract

Concern about claims that premolar extractions may put patients at risk for temporomandibular disorders (TMD) led to this study. We report first findings from a longitudinal study of orthodontic patients begun in 1983. By using the methods of Helkimo, we collected TMD data before initiation of orthodontic treatment, between 0 and 12 months after debanding, and 12 to 24 months after debanding. Analyses related Helkimo scores with premolar extractions in 65 patients for whom orthodontic treatment had been completed. Twenty-six patients were treated without premolar extractions, 25 had four premolars extracted, and 14 had two upper premolars extracted. Tests for significance of differences between mean Helkimo scores were conducted for the nonextraction group compared with the extraction groups, and between pretreatment and posttreatment Helkimo scores for each group.

Results included: (1) no significant intergroup differences between mean pretreatment or posttreatment scores, and (2) small but statistically significant (p less than 0.05) differences (in the direction of improvement) between mean pretreatment and posttreatment scores for both the nonextraction group and for the four premolar extraction group.

Temporomandibular disorders, occlusion and orthodontic treatment

T. Henrikson and M. Nilner (Malmö University, Sweden)
T. Henrikson, Department of Orthodontics, Faculty of Odontology, Malmö University, Carl Gustafs väg 34, S-205 06 Malmö, Sweden.

Journal of Orthodontics, Vol. 30, No. 2, 129-137, June 2003.

This paper is review of three published papers that was presented at the British Orthodontic Society Spring meeting at Heythrop Park in May 2001. The material in this publication is used by permission of Oxford University Press and Swedish Dental Journal. 

The following is a section of the complete article.

ABSTRACT

Objectives: To prospectively and longitudinally study symptoms and signs of temporomandibular disorders (TMD) and occlusal changes in girls with Class II malocclusion receiving orthodontic fixed appliance treatment in comparison with untreated Class II malocclusions and with normal occlusion subjects.

Design: Prospective observational cohort.

Subjects: Sixty-five girls with Class II malocclusion who received orthodontic treatment, 58 girls with no treatment, and 60 girls with normal occlusion.

Method: The girls were examined for symptoms and signs of TMD and re-examined 2 years later. Additional records were taken in the orthodontic group during active treatment and 1 year after treatment

Results: All three groups included subjects with more or less pronounced TMD, which showed individual fluctuation during the ongoing study. In the orthodontic group, the prevalence of muscular signs of TMD was significantly less common post-treatment. Temporomandibular joint clicking increased in all three groups over the 2 years, but was less common in the normal group. The normal group also had a lower overall prevalence of TMD than the orthodontic and the Class II group at both registrations. Functional occlusal interferences decreased in the orthodontic group, but remained the same in the other groups over the 2 years.

Conclusions: (i) Orthodontic treatment either with or without extractions did not increase the prevalence or worsen pre-treatment symptoms and signs of TMD. (ii) Individually, TMD fluctuated substantially over time with no predictable pattern. However, on a group basis, the type of occlusion may play a role as a contributing factor for the development of TMD. (iii) The large fluctuation of TMD over time leads us to suggest a conservative treatment approach when stomatognathic treatment in children and adolescents is considered.

INTRODUCTION
Symptoms and signs of temporomandibular disorders (TMD) are relatively common in children and adolescents.4Go These can appear, increase in frequency and severity during the second decade of life.5,Go6Go Importantly, about 30 per cent of the population of children and adolescents receive orthodontic treatment in most western European countries during this period. This has, arguably, led to claims that orthodontic treatment is a risk factor for the development of TMD have appeared in the literature.7–Go11Go These claims have been questioned and discussed in recent literature reviews.12,Go13Go However, previous studies analysing the role of orthodontic treatment in relation to TMD have often included large age variations and different malocclusions, both in the orthodontic treatment group and, if present, in the control group. Therefore, there is a need for controlled studies to further investigate the relationship between orthodontic treatment and TMD, especially since this relationship still is under debate.

In view of the high prevalence of symptoms and signs of TMD in children and adolescents, it is likely that patients receiving orthodontic treatment could experience TMD before, during, or after their orthodontic treatment.

Results

Clinical findings
Clinical signs of TMD and functional occlusal interferences. The prevalence of clinical signs of TMD at the start and after 2 years is presented in Table 1Go. In the normal group, the overall prevalence of signs of TMD was numerically lower than in the other two groups at both registrations. The general trend was an increased prevalence of signs of TMD over the 2 years. Exceptions to this trend were found in the Orthodontic group, where the prevalence of pain on maximal mandibular movements (P = 0.03) and muscle tenderness to palpation grade 2–3 (P = 0.004) decreased significantly over the 2 years. All three groups had an increased prevalence of TMJ clicking over the 2 years. Only two subjects had reciprocal clicking at both the first and second registration, and no subject developed a closed lock during the 2-year period.

Conclusions
In the individuals, symptoms and signs of TMD and TMD diagnoses fluctuated substantially over time with no predictable pattern. On a group basis, the type of occlusion may play a role as a contributing factor for the development of symptoms and signs of TMD, although this influence is difficult to quantify and predict.

Orthodontic treatment with fixed appliance either with or without tooth extractions did not increase the prevalence of symptoms and signs, or worsen pre-existing symptoms and signs of TMD. Subjects with Class II malocclusion and pre-existing signs of TMD of muscular origin seemed to benefit functionally from orthodontic treatment in a 3-year perspective.

One orthodontic treatment effect when normalizing Class II malocclusions with fixed appliances was a decreased prevalence of functional occlusal interferences, while the changes in subjects with untreated Class II malocclusion and normal occlusion were minor.

This encouraged us to carry out a series of prospective studies to study symptoms and signs of (TMD), and occlusal changes in girls with Class II malocclusion receiving orthodontic treatment in comparison with untreated Class II malocclusions and with normal occlusion subjects.

Early Orthodontic Treatment in the Mixed Dentition

Clayton A. Chan, DDS, MICCMO
Master International College of Craniomandibular Orthopedics

Mothers and fathers are approaching us daily about their children’s crowded teeth, protruding teeth and spaces between the teeth. Today’s parents do not accept the answers given by some dentists and orthodontists when observing that there son or daughter has a problem.  “No treatment is indicated at this time, the patient is too young, the malocclusion will be observed and treated when the permanent teeth erupt in.”  For practitioners, trained with a preventive philosophy, this approach seems completely illogical when statistics have proven that malocclusions when left untreated worsen over time.  The term “supervised neglect” seems very appropriate.

One of the main reasons why your dentist should treat children during the mixed dentition stage of development is that there is such a high incidence of malocclusion in children.  This was quite evident from the Burlington Growth Study, Toronto, Canada, where it was revealed that 75% of children, age 12, have some form of malocclusion.

Since 90% of the face is developed by age 12, practitioners must treat early if they want to guide and, in fact, modify the growth of younger patients.  In our office we emphasize a functional-orthopedic philosophy and favor a two phase orthodontic treatment.

PHASE 1 – Mixed Dentition (Orthopedic Phase)

Thumb sucking, digital habits, anterior and lateral tongue thrusts, airway problems including mouth breathing and snoring and jaw joint (TMJ) problems must be corrected early with functional appliances.  Skeletal problems such as constricted maxillary or mandibular arches and retrognathic mandibles are best treated as early as possible with functional appliances in the mixed dentition period of growth.

PHASE 2 – Permanent Dentition (Orthodontic Phase)

Dental problems are solved with straight wire appliances (fixed) braces in permanent dentition.

One of the main advantages of early treatment is the majority of malocclusions can be corrected without extraction of permanent teeth and non-surgically.  Parents favor the use of functional appliances to correct under-developed mandibles in the mixed dentition stage rather than delay treatment until all the permanent teeth erupt.  To general dentists who are trained to use jaw repositioning appliances such as the Twin Block, Rick-A-Nator and Schwartz appliances, find it ludicrous to wait when children can be treated in 7 to 12 months non-surgically using functional appliances.

The Benefits of Early Treatment

For those patients who have clear indications for early intervention, early treatment presents the opportunity to:

  • Influence jaw growth in a positive manner
  • Simplify and/ or shorten treatment time for later corrective orthodontics
  • Harmonize width of the dental arches
  • Improve eruption patterns
  • Lower risk of trauma to protruded upper incisors
  • Improve some speech problems
  • Correct harmful oral habits
  • Preserve/ gain space for erupting permanent teeth
  • Improve aesthetics and self-esteem
  • Improved breathing / airway problems
  • Reduce likelihood of impacted permanent teeth