13. Basics to Guidance

Question 1

Horizontal sections of Posselt’s border movements first described by who?

Answer 1

• Balkwill and Gysi
• aka Gothic Arch Tracings

Question 2

When border movements are restricted to protrusion and laterotrusive, known as …

Answer 2

Arrow Point tracings

Question 3

Are all tooth contacts good in occlusion?

Answer 3

• no
• a deflective contact changes path of closure
• e.g an RCP-ICP slide deflects mandible into ICP

Question 4

An interferance of occlusion hampers what?
3 examples

Answer 4

• smooth mandibular movement
• anterior-posterior pivot (WS)
• cross-arch pivot (NWS)
• protrusion

Question 5

2 excursive guidance patterns

Answer 5

• canine guidance
• group function

Question 6

Key concepts of occlusion guidance

Answer 6

• idea of disclusion of posterior teeth to avoid interferances
• if the patient has a suitable pattern of guidance, we conform to it

Question 7

Occlusal trauma may cause what?

Answer 7

• pain from PDL
• pain from pulp

Question 8

Why are anterior restorations harder to understand?

Answer 8

no cusps

Question 9

Wy do we have to understand anterior tooth guidance?

Answer 9

• effect of anterior teeth shape is important to mandibular movement
• these are gliding contacts that help to harmoniously guide mandible in and out of ICP

Question 10

What must be avoided when treating occlusion?

Answer 10

• a locked or blocked bite
• patient feeling like they can’t move their teeth when protruding especially

Question 11

When is guidance best?

Answer 11

• starts off slightly shallow and then steepens
• NOT convex - not well tolerated

Question 12

How is the mouth working under a nutcracker system?

Answer 12

• fulcrum is the TMJ, E is the muscles and L is the teeth
• close proximity of TMJ to teeth means high risk of restoration damage
• elevator muscles decrease with anterior guidance

Question 13

Ideal occlusion including tooth, system and patient level

Answer 13

• unilaterally balanced with mutually protected occlusion
• tooth level is a firm multiple simultaneous posterior contacts, light contact anteriorly
• no cuspal incline contacts, contacts down long axis of tooth, smooth shallow guidance
• system is canine guidance usually, NWS and posterior disclusion
• anteriors disclude posteriors in all excursions, freedom in centric occlusion (which is long)
• patient is within neuromuscular tolerances

Question 14

What are articulators?

Answer 14

devices to attach casts in order to stimulate mandibular position and mandibular movement