Lecture 11- Maxillary Posterior Balance Flashcards
What is Balanced Articulation?
an arrangement of the teeth that presents a simultaneous contact of the maxillary and mandibular teeth on the right and left sides and in the anterior and posterior areas in centric and eccentric positions.
What are the five determinants of occlusal balance?
- Condylar guidance
- Incisal Guidance
- Plane of Occlusion
- Compensating Curve
- Cuspal Inclination
What is Condylar Guidance?
the angulation from the horizontal in the sagittal plane that the paths of the condyle form in the TMJ
(components of an articulator that guide the movement of condyle analogs)
Can Condylar Guidance be altered by the dentist?
AWWW HELLL NAAAWWWW
How do you measure condylar guidance on a patient?
by taking eccentric records (lateral and protrusive) to set the articulator
What is the average value of Condylar Guidance that’s sufficient for denture patients?
30 degrees
What is Incisal Guidance?
the angulation from the horizontal line formed by a line drawn in the sagittal plane through the incisal edges of the opposing central incisors when they are in centric occlusion
Increasing horizontal overlap with the same vertical overlap (increases/decreases) incisal guidance
DECREASES
How is incisal guidance determined
by esthetic, phonetic and anatomic requirements
Can Incisal Guidance be altered by the dentist?
YUP! JUST A LITTLE BIT THO! by increasing or decreasing the horizontal overlap
Incisal guidance should be kept at _________ for denture patients.
A MINIMUM!
What is the Plane of Occlusion?
the common plane formed by the incisal teeth and occlusal surfaces of the teeth.
What is the ANTERIOR determining point of the plane of occlusion?
esthetic placement of the teeth
What is the POSTERIOR determining point of the plane of occlusion?
mid-point of the retromolar pad
Plane of occlusion is closely related to the __________ line.
Ala-Tragus Line (Camper’s Line).
What is the Compensating Curve?
the anteroposterior and lateral curvatures in the alignment of the occluding surfaces and incisal edges of the artificial teeth in a balanced occlusion.
related to the Monson Sphere
Must be present to have occlusion
Can the Compensating Curve be altered by the dentist?
YES MA’AM. it is OFTEN altered to restore proper relationship to the determinants when change in cuspal inclination is desired
When must the compensating curve be STEEP?
where there is a STEEP condylar or incisal guidance
What is Cuspal Inclination?
the angle made by the slopes of a cusp with the plane that passes through the tip of the cusps and which is perpendicular to a line bisecting the cusp, measured mesiodistally and buccolingually.
Ordinarily, should be closely related to condylar inclination.
What is the Cuspal Inclination of: Anatomic cusps, Semi-anatomic cusps, and Non-anatomic cusps?
Anatomic- 33-20 degrees
Semi-anatomic- 20
Non-anatomic- 0
4 KEY POINTS.. FLIP CARD!
- all determinants DIRECTLY or INDIRECTLY related
- Condylar guidance CANNOT be changed
- Incisal guidance and plane of occlusion can be changed only SLIGHTLY
- Clinician sets CUSPAL INCLINATION & COMPENSATING CURVE
What is Thielman’s Formula?
Condylar guidance x Incisal guidance/
Compensative curve x Plane of Occ x Cuspal Inclination = 1
What determines the position of mandibular anterior teeth in complete dentures?
- Position of the Upper Anterior teeth
- Lower Ridge Position
- Occlusal vertical Dimension
- Occlusal Scheme selected
Guidelines for the placement of Mandibular Central Incisor:
- Contacts occlusal place
- Has labial inclination
- Contacts midline
- Has 1 mm VO and DO
- Incisal edge follows curvature of ridge
