Bilaterally balanced occlusion
Natural Teeth:
- Natural teeth are attached independently of each other (individual attachment) to the jaws by a desmodontal system specific to them.
- If a malocclusion occurs in a natural tooth, its effect is limited to that tooth and its periodontium.
- The natural tooth can adapt to a malocclusion (migration, rotation, ingression), and as a result the pathological reaction is delayed.
Prosthetic teeth:
- The prosthetic teeth are all fixed together on the same base which rests on a flexible mucosa (collective attachment).
- If a malocclusion affects a prosthetic tooth, it affects the entire arch because all the teeth are interdependent and the base plates transmit the effects of this malocclusion at a distance.
- The possibilities for prosthetic adaptation are zero, so a malocclusion will result in an immediate pathological response (displacement of the prosthesis, mucosal irritations).
In total prosthesis, maximum intercuspidation must always be sought in centric relation, it is universally adopted as a therapeutic position in total prosthesis
OIM = ORC
- Concept of bilaterally balanced occlusion
Definition of an occlusal concept:
It is an occlusal design that defines specific static and dynamic dento-dental contacts unique to each occlusal scheme.
Rules of Fully Balanced Occlusion in Centric Occlusion
simultaneous and bilateral contacts are necessary to ensure the stability of the prostheses on the support surfaces.
No contact between anterior teeth with reduced overjet and overbite = 1mm
Rules of fully balanced occlusion in propulsion
Obtaining at least a stabilizing tripod contact, with an anterior interincisal contact and contacts between the antagonistic second molars.
Or, in addition to an anterior contact, generalized contacts between the mesial sides of the mandibular cusps and the distal sides of the maxillary cusps.
Bilaterally balanced occlusion
Rules of fully balanced occlusion in laterality
In reduction, it is necessary to obtain a stabilizing tripod with two cusp contacts on the working side, and one contact on the non-working side.
- On the working side, contacts between the vestibular and lingual cusp tips of the Antagonist premolars and molars.
- On the non-working side (balancing side), all of the distal-internal slopes of the vestibular cusps come into contact with the mesio-internal slopes of the palatal cusps.
Bilaterally balanced occlusion
The different occlusal diagrams:
a . Generalized fully balanced occlusion
- Fully balanced occlusion described by Gysi (1920) and Hanau (1926).
- The best known and most used concept in total removable prosthesis
b. Non-generalized fully balanced occlusion (Ackermann and Starck)
- In centric relation occlusion and in propulsion, the assembly of the teeth meets the usual criteria.(strack)
- During laterality, the desired contacts and sliding are established:
- on the non-W side, all the internal distal slopes of the palatal cusps come into contact with the internal mesial slopes of the mandibular vestibular cusps
- on the W side, there is no contact on the lingual side but only contacts at the level of the canine and the vestibular cusps of the mandibular PM, the molars being out of contact.
c. fully balanced occlusion with lingual impact (Gerber, 1952)
- The teeth chosen are non-anatomical teeth, the teeth are simulated by the occlusal relief with a pestle-mortar system,
- Only the palatal support cusps come into contact with the antagonist teeth in a cusp/fossa or fossa relationship.
- This distribution of occlusal contacts lingually directs occlusal loads.
- Inocclusion between the mandibular vestibular cusps and the antagonist fossae
d. Sears Assembly
- Non-engaging assembly
- Use of flat teeth that allow horizontal propulsion
- The functional forces generate significant horizontal components if the cusp slopes are very inclined.
By using teeth with less inclined slopes, the pressures applied to the bone and mucosa are moderate.
The objectives of this occlusal concept:
1- Ensure the stability of the prostheses:
Static and dynamic occlusal contacts generate forces directed by the cuspal slopes of the prosthetic teeth which must contribute to prosthetic stability.
2- Preservation of support tissues:
the prosthetic base transmits occlusal forces to the supporting tissues whose intensity and orientation may hinder physiological stimulation or accelerated resorption.
3- Restoration of mastication, phonation, and swallowing functions:
– masticatory efficiency depends on the position of maximum intercuspation.
– phonation depends on the assembly and especially on the anterior teeth.
– swallowing causes the most numerous and longest interdental contacts.
Conclusion
In this position, the prostheses must be perfectly stable, the result is obtained thanks to a precise recording of the intermaxillary relationships , a mounting, and a balancing resulting in equal and equally distributed contacts between the prostheses, both in the anteroposterior and transverse directions.
Bilaterally balanced occlusion
Cracked teeth can be healed with modern techniques.
Gum disease can be prevented with proper brushing.
Dental implants integrate with the bone for a long-lasting solution.
Yellowed teeth can be brightened with professional whitening.
Dental X-rays reveal problems that are invisible to the naked eye.
Sensitive teeth benefit from specific toothpastes.
A diet low in sugar protects against cavities.