Periodontal considerations in restorative dentistry 1

Question 1

aims of periodontal therapy

Answer 1

• To arrest the disease process
• Ideally, to regenerate lost tissue
• To maintain periodontal health long term

RESULT = prevention of tooth loss

Question 2

periodontal therapy as aid to restorative dentistry

Answer 2

• Improves soft tissue management
• Establishes stable gingival margin position
• Contributes to aesthetics
• Reduces tooth mobility
• Informs prognosis

Question 3

issues with inflammed gingival margins

Answer 3

• Bleeds during operative procedures
• Is unstable in its apico-coronal location
• Makes effective restorative dentistry impossible

Gingival recession following non-surgical periodontal therapy

• Black triangles
• papilla loss

Question 4

issue here

Answer 4

Gingival inflammation and papilla loss associated with a poorly fitting veneer and excess luting cement

• Rolled inflamed gingivitis

2 weeks after removal of veneer and debridement there has been further gingival recession

• Stable now

Question 5

affect on gingval margin of effective non-surgical and surgical Tx on periodontitis

Answer 5

recession

Question 6

gingival margin position and restoration placement

Answer 6

crucial

needs to be stable

Question 7

stable gingival margin when

Answer 7

it is healthy

In general the gingival margin should be monitored for at least 3-6 months AFTER completion of periodontal treatment to check that it is stable.

• Once stability confirmed – THEN place restorations

need to wait, try to manage pt

Question 8

4 prosthodontic options for partially dentate

Answer 8

• FPD with natural abutments (bridges)
• RPD with natural abutments
• Implant supported prosthesis
• Combinations of the above

Question 9

potential damages from crowns and bridges

Answer 9

• Plaque retention
  
  • Location and fit of restoration margins
  • Contour of retainers and pontics
• Unfavourable transmission of occlusal forces
• Pulp damage

Question 10

potential damages for RPDs

Answer 10

• Plaque retention
  
  • Gingival margin coverage
• Direct trauma from components
• Unfavourable transmission of forces (occlusal, insertion and removal etc)

Question 11

fixed vs removable prosthetics?

Answer 11

From a periodontal perspective fixed prostheses are usually preferable

assume done well

Question 12

issue here

Answer 12

Poor fit

Cover gingival margin

Even with excellent plaque control – hard/impossible to keep clean

so Gingival inflammation of palate – damage to adj tissues

Question 13

good RPD design for periodontal health

Answer 13

• Effective tooth support
• Clearance of gingival margins
• Rigid connectors
• CoCr alternative*
• Relief around gingival margins – wont accumulate plaque
• Acrylic can work too – esp with clasps – clear gingival margin aim*

Question 14

restoration margins

Answer 14

never perfect

all will attract plaque

poorer ones = attract more

Question 15

issue here

Answer 15

Persistent inflammation associated with poorly fitting subgingival crown margins

• accumulated plaque, cannot clean as subgingival

inflammation around laterals and centrals

Question 16

supracrestal attachment

Answer 16

tissues are histologically composed of the junctional epithelium and supracrestal connective tissue attachment.

• The term biologic width should be replaced by supracrestal tissue attachment (Since 2017 classification)

average of 2mm – vary between people and sites in mouth

• above crest of alveolar bone
• some extend above ACJ, junctional epithelium can vary (attached to cementum and dentine sometimes extend to enamel)

don’t want to infringe on supracrestal attachment when placing margins

Question 17

interproximal area consideration

Answer 17

supracrestal attachment extends coronally

flows around contour of tooh

Question 18

where should restoration margins sit

Answer 18

supeiror to supracrestal attachment

Question 19

4 possible outcomes of restoration margins encroaching on supracrestal attachment

Answer 19

• Persistent inflammation
• Loss of attachment
• Pocketing
• Recession

Question 20

issue here

Answer 20

lost supracrustal attachment of papilla as crown margin kept at one level all the way round tooth not respected interdental papilla

Question 21

supracrestal attachment

bone

crown margin

positioning?

Answer 21

The supracrestal tissue attachment can be accommodated between the crown margin and the bone. - want at least 2-3mm between crown margin and bone

• If the inflammation can be resolved the crown margins will become accessible.

Question 22

importance of well fitting provisional restorations

Answer 22

Indication of how good crown prep is

• If doesn’t look right then final restoration won’t be

is it?

• thin in places
• margins not in right place
• interdental brushing – specify to lab, send with casts
• too apical –> will lose interdental papilla

Question 23

Healthy Tissue + Carefully located preparation margins =

Answer 23

Easy impression + Reduced risk of disease

Follow height of gingival margin contour

Question 24

issue here

Answer 24

Restoration margins encroaching on supracrestal tissue attachment

Too subgingival margins

Question 25

how to resolve prepared margins that are too subgingival

Answer 25

surgical crown lengthening Not enough space between restoration margin and alveolar bone -\> Inflammation Flap raised as need to lower bone as cannot alter prep to be more coronal as already done **- to get 3mm** * supracrestal margin and gingival margin can reform so no more on going inflammation due to restoration margin Not reliable can get rebound and recession

Question 26

treatment here

Answer 26

Through bone removal and manipulation of the muco-periosteal flap the **supracrestal tissue attachment** has been relocated apically, allowing access to the crown margins and facilitating a return to tissue health. * Will likely need to replace crowns – wait 6 months so stable

Question 27

overhanging restoration issues

Answer 27

* associated with more inflammation and bone loss * than non-restored sites (Gilmore 1971) * larger the overhang - greater the bone loss (Jeffcoat et al 1981) * development of pathogenic flora (Lang 1983 USE A WEDGE

Question 28

contour of restoration

Answer 28

should be same as tooth hard for pt to clean if incorrect don’t try to compensate for gaps/black triangles with long contact points * hard to clean -\> periodontitis – inflammation, swelling of tissues, poorly contoured prep (bulbous crowns)

Question 29

result of incorrect tooth prep

Answer 29

crowns will be wrong shape (bulbous, look bad) technicians have no choice but to work with what you give

Question 30

keys to periodontally successful indirect restorations

Answer 30

* Start with healthy tissue * Adequate tooth preparation * Precise margin location * Excellent provisional restorations * Careful tissue handling and impression technique

Question 31

3 questions when considering replacing teeth in pts with periodontitis

Answer 31

* Is there a need to replace missing teeth? * With what should they be replaced * What are the problems in replacing missing teeth in patients with Periodontitis?

Question 32

2 considerations when replacing teeth in pts with periodontitis

Answer 32

prognosis support

Question 33

prognosis Q in periodontitis pts

Answer 33

Will more teeth be lost in the near future? Chart down the individual prognosis of each tooth * Resorted, carious, periapical pathology, bone level, mobile * Overeruption and drifting of anterior teeth* * Periodontitis stable* * Hard but able to restore*

Question 34

support principle

Answer 34

Ante’s Law * The combine periodontal area of the abutment teeth should be equal to or greater than the periodontal area of the tooth/teeth to be replaced e. g. canine replace – root surface area of abutment needs to be = or \> root surface area of canine – so lateral no

Question 35

what are concerns regarding support in periodontitis pts?

Answer 35

* Abutments which are periodontal compromised will be ‘overloaded’ * Periodontitis will be made worse * The teeth will be ‘loosened’

Question 36

Ante's Law

Answer 36

* The combine periodontal area of the abutment teeth should be equal to or greater than the periodontal area of the tooth/teeth to be replaced

Question 37

periodontal procedures that can aid restorative dentistry (4)

Answer 37

* Excessive gingival display (gummy smile) * Gingival overgrowth making restorative dentistry impossible * Lack of clinical crown height making retention of restoration impossible * Camouflage of gingival recession

Question 38

soft tissue harmony concerned about

Answer 38

* Gingival health * Gingival display * General gingival inclination * Gingival outline and symmetry Optimal gingival aesthetics – can assess and analyse pt complaint

Question 39

gingival zenith

Answer 39

most apical point of gingival marginal scallop

Question 40

gingiva papilla

Answer 40

dip coronally intedentally

Question 41

approximation of line of zeniths

Answer 41

canine to canine touching central incisors lateral incisors generally 1-2mm below parallel to incisal edges of centrals

Question 42

smile line options

Answer 42

* Average/medium see papilla just * High – see large extent papilla * Low – no gingiva seen

Question 43

pt here has

Answer 43

gummy smile * appears to have small, square teeth * More gingiva on pt right than left * Teeth slightly shorter on right than left Pockets 3mm or less – so not deep – no inflammation Supracrestal attachment sits coronally Can sound for bone – callipers * Reasonable long way away 5mm Can have gingival margin moved up as still have 3mm between gingival margin and bone * More tooth show, less gingiva show in smile

Question 44

how to assess smile

Answer 44

incisal margin how it relates to interpupillary line * Gingival zenith line running parallel? Symmetry of smile * Where is the asymmetry – occlusal cant - Position of maxilla? Or gingiva margin level? (here combination)

Question 45

gingival hypertrophy

Answer 45

drug induced (ca channel blockers) makes restorative dentistry impossible until tx gingiva grown over where crowns are * Try to improve plaque control – but impossible for pt to maintain due to overgrowth – impossible to clean Remove tissue – scalpels and lasers Allow to heal * Able to restore but not ideal after week or two * Year later – rebound overgrowth of gingiva – common in drug induced * If doesn’t bother pt and under control – keep under review

Question 46

issue here

Answer 46

lack of clinical crown heigh so retention of resotration impossible check Radiographs * no bone loss and reasonable root length Consider – to lengthen crowns to restore them and to maintain supracrestal attachment width will need to remove bone

Question 47

crown lengthening surgery

Answer 47

if clinical crown height too small for retention of restoration radiograph - assess bone level and root status Diagnostic wax up of what aim to achieve * Cut the cast to level want to cut gingiva to after placing wax restorations * generate stent, place onto pt mouth in surgery so know where to cut to (at least 3mm of space between gingival margin and bone) After crown lengthing surgery – revealed some tooth structure that can utilise for provisional restorations

Question 48

camouflage gingival recession

Answer 48

recession defects Black triangles – no way to surgically correct (no way to replace missing papilla)– think around * Acrylic gingival veneer * Pink acrylic * Plaque trap – so minimise wearing – only when going out and will be self concious

Question 49

possible tx for uneven tooth width, margins and contact points

Answer 49

restorations can camouflage recession Reshaping of teeth to redistribute size/width, placement of margin, contact points * Can end up with long teeth * These restorations are mainly supra gingival – barely into gingival sulcus * low – medium smile line helps * Contact point left shorter for ease of cleaning use of Stents and casts Compromise – canine still prominent but gingival margin more even