Occlusal concepts Balanced and nonbalanced occlusion incisal guidance

Occlusal concepts : Balanced and non-balanced occlusion, incisal guidance and condylar guidance

OCCLUSION • The act or process of closure or of being close or shut off. • The static relationship between the incising or masticating surfaces of the maxillary of mandibular teeth or tooth. The glossary of Prosthodontic terms, 1999

ARTICULATION The static and dynamic contact relationship between the occlusal surfaces of the teeth during function. The glossary of Prosthodontic terms, 1999

PRINCIPLES OF OCCLUSION FOR COMPLETE DENTURES • Initial and complete occlusal contact in centric relation (called “centric occlusion”) • All anterior and posterior denture teeth inclines and surfaces must function as a “unit” during excursive movements • Any prematurity must be eliminated • Posterior denture teeth contact when protrude • Anterior tooth contact is contraindicated in centric occlusion

OCCLUSION FOR COMPLETE DENTURES 1) Balanced occlusion • Bilateral, simultaneous • Anterior and posterior occlusal contact in centric and eccentric positions 2) Monoplane occlusion • Positioned in a single plane 3) Lingualized occlusion • The maxillary lingual cusp with the mandibular occlusal surface in centric, working and non-working mandibular positions

SELECTING THE OCCLUSAL SCHEME • Anatomic tooth • Semi-anatomic tooth • Non-anatomic tooth Rahn AO. , Ivanhoe JR. , Plummer KD. , Textbook of complete dentures. 6 th ed. People’s Medical Publishing House, CT, 2007.

Concepts of occlusion • • Anatomic, balanced Semi-anatomic, balanced Non-anatomic, balanced Lingualized balanced • Conventional monoplane • Neutrocentric concept • Lingualized, non-balanced

BALANCED OCCLUSION • Anatomic, balanced • Semi-anatomic, balanced • Non-anatomic, balanced • Lingualized balanced

ANATOMIC, BALANCED AND SEMI-ANATOMIC, BALANCED • Anatomic tooth ≥ 30° Semi-anatomic tooth < 30° • การสบพรอมกนทงสองขางของฟนหนาและฟ นหลง ทงการสบในศนยและนอกศนย http: //www. ffofr. org/education/lectures/complete-dentures/occlusal-schemes-anatomic-and-semi-anatomic-occlusion/

ANATOMIC, BALANCED AND SEMI-ANATOMIC, BALANCED • มทง cross-tooth และ cross-arch • ลด tipping movement Rahn AO. , Ivanhoe JR. , Plummer KD. , Textbook of complete dentures. 6 th ed. People’s Medical Publishing House, CT, 2007.

ANATOMIC, BALANCED AND SEMI-ANATOMIC, BALANCED • ม compensating curve • เกดแรงทางดานขางตอสนเหงอก (lateral force) http: //quizlet. com/17575939/complete-denture-set-up-flash-cards/ Basker RM. , Davenport JC. , Prosthetic treatment of the edentulous patient. Oxford: Blackwell, 2002.

NON-ANATOMIC, BALANCED • Non-anatomic tooth = 0° • ม compensating curve • ฟนหนาม vertical overlap • การเรยงฟนทระนาบบดเคยวเรยบเป นระนาบเดยว เกด lateral force ทฟนหนา Christensen’s phenomenon

NON-ANATOMIC, BALANCED Balance เกดขนไดจาก • Flat occlusal plane with balancing ramp • Flat occlusal plane and inclined plane of orientation (slight compensating curve) • Flat occlusal plane and a Monson curve or positive compensating curve • Flat occlusal plane and/or negative curve of Wilson (ไมม compensating curve)

NON-ANATOMIC, BALANCED Balance เกดขนไดจาก • Pleasure curve • ม balancing ramp • 2 nd premolar – Li cusp > B cusp (Anti-Monson) • 1 st molar – Li cusp = B cusp • 2 nd molar – B cusp > Li cusp (Monson) http: //www. authorstream. com/Presentation/rahul. ahirrao-1690965 -balanced-occlusion-complete-denture/

NON-ANATOMIC, BALANCED http: //www. docstoc. com/docs/101369963/Occlusion-in-complete-denture

LINGUALIZED BALANCED • ใชฟนปลอมทม cusp ทงฟนบนและลาง • ในตำแหนง centric – maxillary lingual cusp สบกบฟนลาง (Buccal cusp ไมสบ ) Rahn AO. , Ivanhoe JR. , Plummer KD. , Textbook of complete dentures. 6 th ed. People’s Medical Publishing House, CT, 2007.

LINGUALIZED BALANCED • ม cross-arch แตไมม cross-tooth http: //www. docstoc. com/docs/101369963/Occlusion-in-complete-denture

LINGUALIZED BALANCED ขอด • ชวย ลด lateral force เมอเปรยบเทยบกบ anatomic/semi-anatomic balanced • เรยงฟนใหได bilateral balanced ไดงาย

NON-BALANCED OCCLUSION Non-balanced occlusion (Monoplane occlusion) • Conventional monoplane • Neutrocentric concept • Lingualized, non-balanced

CONVENTIONAL MONOPLANE • ฟนหนาไมม • จดตง vertical overlap occlusal plane ใหขนานกบ guidance และ incisal guidance • ทำหรอไมทำ facebow transfer กได condylar

LINGUALIZED, NONBALANCED • ฟนปลอมบนใชแบบ anatomic/semi-anatomic tooth ฟนปลอมลางใชแบบ non-anatomic tooth • ในตำแหนง centric – maxillary lingual cusp สบกบฟนลาง (Buccal cusp ไมสบ ) Rahn AO. , Ivanhoe JR. , Plummer KD. , Textbook of complete dentures. 6 th ed. People’s Medical Publishing House, CT, 2007.

LINGUALIZED, NONBALANCED • ไมม cross-tooth และไมม cross-arch • ใชไดในความสมพนธของขากรรไกรแบบ II, class III และ crossbite class http: //www. neuronarc. com/lingualized-occlusal-scheme. html

FACTORS INFLUENCING BALANCED OCCLUSION Hanau’s Quint 1. Condylar guidance 2. Incisal guidance 3. Occlusal plane 4. Compensating curve 5. Inclination of the cusp Textbook of prosthodontics, Jaypee Brothers Publishers, 2013.

1. CONDYLAR GUIDANCE • Generated by condyle and articular disc traversing contour of glenoid fossa • Mechanical form located in upper posterior region of an articulator that controls movement of its mobile member http: //www. authorstream. com/Presentation/a. SGuest 18776 -189861 -balanced-occ-part-science-technology-ppt-powerpoint/

1. CONDYLAR GUIDANCE • The movement of the head of condyle down the articular eminence • Obtained by mean of a “protrusive registration record” • Determined by patient (cannot change) http: //www. authorstream. com/Presentation/rahul. ahirrao-1690965 -balanced-occlusion-complete-denture/

1. CONDYLAR GUIDANCE • Increase in condylar guidance will increase jaw separation during protrusion • In patients with steep condylar guidance, incisal guidance should be decreased to reduce amount of jaw separation produced during protrusion

2. INCISAL GUIDANCE • “The influence of the contacting surfaces of the mandibular and maxillary anterior teeth on mandibular movements” http: //www. authorstream. com/Presentation/rahul. ahirrao-1690965 -balanced-occlusion-complete-denture/

2. INCISAL GUIDANCE • Influence of contacting surface of guide pin and guide table on articulator movement http: //www. authorstream. com/Presentation/a. SGuest 18776 -189861 -balanced-occ-part-science-technology-ppt-powerpoint/

2. INCISAL GUIDANCE • Angle of incisal guidance is largely under influence of dentist • But there are certain limitations like • • • Ridge relation Arch shape Ridge fullness Inter ridge space Phonetics &esthetics requirement of patient • With in range of these limitations incisal guide angle can be altered considerably

2. INCISAL GUIDANCE • This factor is influenced by amount of horizontal, vertical overlap • Greater horizontaloverlap = Lesser angle of inclination • Lesser the verticaloverlap = Lesser angle of inclination http: //www. authorstream. com/Presentation/rahul. ahirrao-1690965 -balanced-occlusion-complete-denture/

2. INCISAL GUIDANCE • Determined during anterior try-in • Influenced by the amount of vertical and horizontal overlap • The less the vertical overlap, the less the angle of inclination • More influenced on posterior teeth than condylar guidance http: //www. authorstream. com/Presentation/rahul. ahirrao-1690965 -balanced-occlusion-complete-denture/

3. OCCLUSAL PLANE • Imaginary line from incisal edge of central incisal – DB cusp of 2 nd molar • Parallel to ala-targus line/Camper’s line • Tilting of the plane >10 degree is not advisable http: //www. authorstream. com/Presentation/rahul. ahirrao-1690965 -balanced-occlusion-complete-denture/

4. COMPENSATING CURVE • Determined by inclination of posterior teeth and their vertical relationship to occlusal plane. • 2 types of curves • Anteroposterior compensating curve • Mediolateral compensating curve http: //www. authorstream. com/Presentation/rahul. ahirrao-1690965 -balanced-occlusion-complete-denture/

5. INCLINATION OF THE CUSP • High cuspal inclination high lateral force textbook of prosthodontics, Jaypee Brothers Publishers, 2013.

REFERENCES • Rahn AO. , Ivanhoe JR. , Plummer KD. , Textbook of complete dentures. 6 th ed. People’s Medical Publishing House, CT, 2007. • Basker RM. , Davenport JC. , Prosthetic treatment of the edentulous patient. Oxford: Blackwell, 2002. • Textbook of prosthodontics, Jaypee Brothers Publishers, 2013. • http: //www. ffofr. org/education/lectures/complete-dentures/occlusal-schemes-anatomic-and-semi-anatomicocclusion/ • http: //www. authorstream. com/Presentation/rahul. ahirrao-1690965 -balanced-occlusion-complete-denture/ • http: //www. authorstream. com/Presentation/a. SGuest 18776 -189861 balanced-occ-part-science-technology-ppt-powerpoint/