periodontal surgery Flashcards
1
Q
definition
A
prevents or corrects anatomical, traumatic, developmental or plaque-induced defects in the bone, gingiva or alveolar mucosa
2
Q
general objectives
A
arrest disease progression by improving plaque control
- create accessibility for effective RSD
- improve gingival/root morphology to facilitate the pts’ self-care
regenerate the lost PD attachment
maintain proper embrasure space
3
Q
at what point in the tx plan is it done?
A
after re-evaluation
before reconstruction
4
Q
PD plastic surgery objectives
A
correction of gingiva-alveolar mucosal problems
preparation of adequate PD architecture prior to Rx tx
aesthetic improvement
5
Q
why is initial NST important?
A
allows evaluation of pts’ motivation and plaque control
improves ST consistency for easier surgical management
some deep pockets may heal following NST
6
Q
contraindications to surgical tx
A
bad plaque control
smoking
7
Q
when should decision-making at reevaluation stage take place?
A
at least 6-8 weeks after completion of non-surgical phase
8
Q
decision-making at re-evaluation stage outcomes
A
no success
full success
partial success
9
Q
decision-making at re-evaluation stage outcomes - no success
A
> 4mm, high BOP, high PI, poor OH
repeat HPT
if pt completely not motivated discontinue active tx and provide supportive care
10
Q
decision-making at re-evaluation stage outcomes - full success
A
≤4mm, BOP <10%, good OH, inflammation resolved
supportive care and regenerative surgery
11
Q
decision-making at re-evaluation stage outcomes - partial success
A
v good OH, reduction in number of >4mm pockets and reduced BOP but still both deeper pockets and BOP present
PD access surgical therapy
12
Q
types of PD surgery
A
access therapy
resective therapy
regenerative therapy
mucogingival therapy - PD plastic surgery
13
Q
access therapy aim
A
to gain more access to the root surface in persisting pockets
14
Q
resective therapy aim
A
to remove infected ST of the gingivae and infected bone
15
Q
when is resective therapy used?
A
now only used in specific cases
- furcation resective tx
- tunnel prep
- root resection/separation
- gingivectomy (only in hyperplasia)
- crown lengthening (before prosthetic tx)
16
Q
regenerative therapy
A
GTR and GBR
infrabony defects
augmentation of the edentulous ridge
17
Q
mucogingival therapy - PD plastic surgery
A
gingival augmentation
root coverage
gingival preservation at ectopic tooth eruption
preservation of ridge collapse associated with tooth extraction
18
Q
OFD
A
doesn’t have resective part nowadays
access
removal of granulose tissue and instrumentation of the root surface
flaps replaced to their original position
no attempts to reduce the pre-op depths of the pockets
19
Q
OFD incisions
A
horizontally
- intracrevicular incision made through base of gingival pocket and entire gingivae
- /crevicular/sulcular
vertically
- none (envelope incision - flap extended horizontally)
- one or two vertical incisions
mucoperiosteal full thickness flap formation
20
Q
OFD types of flap
A
split the papilla - conventional flap
papilla preservation flap - push papillae through embrasure with a blunt instrument to be included in the facial flap
21
Q
OFD post op care
A
reinforce mechanical plaque control
don’t brush area for 24hours, then soft baby toothbrush
CHX MW for 1-2 wks
analgesics 2-3 days
only prescribe ABs if complications in healing
remove sutures after 1wk
22
Q
healing following OFD
A
organisation of blood clot and replacement by collagenous CT
attachment by means of a long JE (2-4wks)
reduction in probing depths as a result of gingival recession and gain in clinical attachment
23
Q
Modified Widman flap procedure
A
vertical relieving incisions
scalloped inversed bevel incision 1mm from gingival margin
intra-sulcular incision to the bone crest to separate the tissue collar from the root surface
remove ST collar
don’t remove the crystal bone anymore as in the original procedure
debridement and remove GT
close flap
24
Q
gingivectomy indications
A
gingival enlargement/overgrowth
idiopathic gingival fibromatosis
false pockets
- enlargement of the gingival tissue without apical migration of the JE attachment
minor corrective procedures
procedure done during lengthening of the crowns before prosthetic tx
25
purpose of gingivectomy
reduction of gingival excess
- to facilitate plaque control
- to facilitate Rx dentistry
- to improve appearance
26
what must be done before considering gingivectomy?
control causative factors of gingival enlargement
27
gingivectomy procedure
identify bottom of pocket with probe
mark outer aspect of the gingivae creating a bleeding point (can get instrument with probe and dot bit)
scalloped external bevel incision (45 degrees to long axis of the roots) apical to the bleeding points to terminate at level slightly to the bottom of the pockets
removal of attached gingiva
gingivoplasty to create a better aesthetic contour
RSI
periodontal dressing to cover area
- exposed tissue will heal by secondary intention
can use gingivectomy knives or scalpel
28
PD dressings and tissue adhesives
reduce post-op pain
prevent colonisation of plaque
left in situ for 7-10 days
a 2nd dressing may be indicated if healing is inadequate
only eugenol-free dressings are recommended
Peripac
Coe-pack
29
Peripac
ready to use
gypsum base and acrylic
sets quickly when contacting with saliva
hard edges - danger of pressure aphthous ulcer
30
Coe-pack
2 components - zinc oxide and fatty acids
| pliable after setting
31
probing mesial furcation
from palatal aspect
32
probing distal furcation
from buccal aspect
33
furcation
the anatomical area where the roots divide
34
furcation defect/involvement
bone loss at the branching point of the roots
| can only be present on multi-rooted teeth
35
furcation involvement and prognosis
significantly worsens the tooth prognosis (x8)
36
naming furcations
buccal, mesial or distal furcation
37
diagnosing furcations
clinical exam - visual assessment and probing
| radiographic assessment - easier mandible
38
other teeth which may have furcations
some premolars
- 40% of U4s have 2 roots
may also be present in teeth which normally only have 1 root - incisors, canines, L premolars
39
Grade 1 furcation lesion
an early lesion
| up to 3mm of horizontal AL
40
Grade 2 furcation lesion
>3mm horizontal AL but not through and through
41
Grade 3 furcation lesion
'through and through' from one furcation entrance to another
42
tx objectives for furcation lesions
the elimination of microbial plaque from the exposed surface of the root complex
the establishment of an anatomy of the affected surface that facilitates proper self-performed plaque control
43
tx options for furcation lesions
```
1 palliate - maintain plaque control
- supportive care - RSD
2 repair
- RSD (small furcation), OFD
3 regeneration
- GTR, GBR, Emdogain
4 eliminate - resective tx
- root resection, hemisections, furcation plasty, tunnel procedure, extraction
```
44
furcation lesions tx - palliative tx - non-surgical debridement
non-symptomatic
functional
not amenable to curative tx
periodic debridement - must maintain good plaque control
because of access difficulties, likely to be successful only in txing early (grade 1) lesions
45
furcation lesions tx - OFD
evidence suggests similar long-term outcomes can be expected from both closed and open debridement of furcation lesions
46
furcation lesions tx - regenerative procedures - pros and cons
furcation sites can provide good space maintenance and clot protection
BUT
- difficult to adequately debride
- relatively avascular
47
furcation lesions tx - regenerative procedures - indications for periodontal regeneration
2 and 3 walled proximal defects
Grade 2 mandibular furcation defects
Grade 2 buccal maxillary furcation defects
48
furcation lesions tx - regenerative - GTR/GBR
compared with OFD, GTR results in greater vertical and horizontal bone fill
- results are better in mandibular furcation
- 1.5mm more bone fill (horizontal)
GTR and bone graft gives even better results
49
Biologics - Straumann Emdogain
a mix of enamel matrix proteins (derived from porcine tooth germ) that when applied to a clean root surface or oral wound, form an ECM that stimulates cells and processes that are fundamental for PD regeneration and ST wound healing - matrix mediates production of cementum
50
resective tx for furcation lesions
aims to eliminate the furcation
- furcation plasty (mainly at buccal and lingual furcation)
- tunnel preparation (to tx deep degree 2 and 3 furcation defects in L molars)
- root resection/separation/hemisection
51
furcation lesions resective tx - tunnel procedure
bone and tooth recontoured to allow insertion of an interdental brush
take care not to perforate pulp chamber
tend to do for through and through
52
furcation lesions resective tx - root resection
endo tx before
| cut one root off
53
furcation lesions resective tx - hemisection
endo tx
cut tooth in half
e.g. distal half of a hemisected molar is extracted, the mesial half is restored as a premolar
54
furcation lesions resective tx - requirements for successful procedures
endo tx must be successful
root separation and removal must be feasible
remaining roots should not be hypermobile
remaining tooth structure should be restorable
pt should be dextrous and motivated enough to maintain plaque control
additional caries prevention strategies may be required to prevent caries of the exposed root
55
what defects are teeth predominantly compromised by?
intrabony or intraradicular defects
56
tx objective of regenerative therapy
obtain shallow, maintainable pockets by reconstruction of the destroyed attachment apparatus and therefore also limit recession of the gingival margin
57
aims of regenerative therapy
increase in PD attachment of severely compromised teeth
decrease in deep pockets to a more maintainable range
reduction of the vertical and horizontal component of furcation defects
58
types of pocket - horizontal bone loss
supra bony pocket
base of the pocket is located coronally to the alveolar crest
easier to tx
59
types of pocket - vertical bone loss
infra bony pocket, angular defect
1 - crater - affects 2 adjacent teeth
2 - intrabony defect - affects 1 tooth
60
classification of intrabony defect
number of walls of bone present
- one wall intrabony defect
- 2 wall intrabony defect
- 3 wall intrabony defect - best to regenerate
61
triad of tissue engineering
scaffold
cells
signalling molecules
62
infra bony defect management
closed RSD - healing by repair
- quite unsuccessful as no access/visibility, relying on tactile sensation
open RSD
pocket elimination with osseous resection - rarely used nowadays
regenerative techniques
63
biological mediators
```
platelet-derived growth factor
insulin growth factor
transforming growth factor B
bone morphogenetic proteins
prostaglandin
fibronectin
enamel matrix proteins
```
64
strategies for PD regeneration
space maintenance and clot protection
selective cell repopulation
provision of progenitor cells
use of biological mediators - signalling molecules
= regenerative techniques may employ one or more of the above strategies
65
Emdogain regenerative procedure
```
flap
OFD (get env suitable for regeneration)
etch
Emdogain
suture tissues
```
66
GTR
based on the assumption that only the PDL cells have the potential for the regeneration of the attachment apparatus of tooth
place barriers of different types to cover the bone and PDL therefore temporarily separating them from gingival epithelium
- gingival epithelium - much faster than PDL cells so prevents healing of pocket
excluding the epithelium and the gingival CT from the root surface during the post-surgical healing phase
- prevents epithelial migration into the wound
- favours repopulation of the area by cells from the PDL and bone cells
GTR with the use of barrier membranes works on the principle of cell exclusion
- don't expose membrane to oral cavity - will get infected. Must suture above membrane
67
types of membrane - GTR
```
bioabsorbable - good for smaller pockets
1 - natural
- collagen type
- synthetic polymer type (lactate-glycol compound)
- CT graft
- Durameter
- oxidised cellulose
2 - synthetic
- alloderm
- polyurethanes
- polylactic acid
- polyglycolic acid
```
non-absorbable
- millipore filter
- e-PTFE membrane GORE-TEX
- nucleopore membrane
- rubber dam
- ethyl cellulose
- semi-permeable silicone barrier
68
bone grafts - objectives
space maintenance and clot protection
osteoconduction - scaffold
osteoinduction - promoting OB activity
osteogenesis - OBs present in graft
69
osteoconduction
scaffold
70
osteoinduction
promoting OB activity
71
osteogenesis
OBs present in graft
72
GBR
osseous defects covered with a barrier membrane, which adapts closely to the surrounding bone surface
- our cells destroy the product and that forms the new bone
non-osseous cells (epithelial cells and fibroblasts) are inhibited and space is preserved between the bone surface and membrane
OBs derived from the periosteum and bone are selectively induced on the osseous defect area, facilitating new bone formation
GBR is for the regeneration of supporting bone
73
autografts
same individual
safest - no rejection
EO - iliac crest, tibia, fibula, ribs
IO - chin, exostoses, torus, ramus, tuberosity
- no scars or GA - but can't obtain a lot of bone, good enough for perio surgery but not for OMFS
74
isografts
genetically identical
75
allografts
same species
DFDBA - Demineralised Freeze Dried Bone Allografts - contain BMPs
FDBA
frozen
76
alloplasts
synthetic
- hydroxyapatite
- calcium phosphate cements (CPC)
- B tricalcium phosphate (TCP)
- biphasic alloplastic materials
- bioactive glasses
- synthetic polymers
77
xenografts
different species
- bovine derived
- porcine derived
- coralline calcium carbonate
78
composite grafts
ceramics and bioactive molecules
79
bone grafts technique
use modified papilla preservation technique - debride first
80
mucogingival therapy
PD deficiency - black triangle, dental recessions
| mostly aesthetic but can save important teeth for young people
81
recession
the displacement of the gingival soft tissue margin apical to the CEJ which results in exposure of the root surface
- inevitable after successful HPT - can look worse when inflammation resolved in a true pocket
free gingiva, attached gingiva, mucogingival jct
82
recession aetiology
inflammatory process
- PDD
- gingival biotype
mechanical/physical factors
83
recession aetiology - mechanical/physical factors
vigorous brushing/hard bristles/horizontal scrubbing - pts with good OH
traumatic incisal relationship can cause stripping of the gingival tissues
trauma from foreign bodies e.g. lower lip piercings
prominent teeth out of alignment of the arch esp if there is a thin gingival biotype overlying the dehiscence
aberrant frenal attachments due to an apical pull on the gingival tissues
high frenal attachments (close to the gingival margin) making OH difficult therefore leading to a localised PD problem and subsequent recession
iatrogenic damage caused by Rx tx which involves placement of subgingival margins of Rxs can directly impinge on the biologic width
ortho tx not respecting amount of the width of the dental alveolus
84
PD Miller's classification of gingival recession
```
class 1
class 2
class 3
class 4
```
85
PD Miller's classification of gingival recession - class 1
marginal tissue recession that does not extend to the mucogingival jct
86
PD Miller's classification of gingival recession - class 2
marginal tissue recession that extends to or beyond the mucogingival jct, with no PD AL (bone or ST) in the interdental area
87
PD Miller's classification of gingival recession - class 3
marginal tissue recession that extends to or beyond the mucogingival jct, with PD AL in the interdental area or malpositioning of teeth
88
PD Miller's classification of gingival recession - class 4
marginal tissue recession that extends to or beyond the mucogingival jct, with severe bone or ST loss in the ID area and/or severe malpositioning of teeth
89
RT1
no loss of IP attachment
| IP CEJ is clinically not detectable at both mesial and distal aspects of tooth
90
RT2
gingival recession associated with loss of IP attachment
| amount of IP AL ≤ buccal AL
91
RT3
gingival recession associated with loss of IP attachment
| amount of IP AL > buccal AL
92
IP AL
measured from IP CEJ to depth of IP sulcus/pocket
93
recession symptoms
```
dentine hypersensitivity
cervical caries
cervical abrasion and erosion
poor aesthetics
loss of vitality - tooth loss
```
94
tx of recession
monitoring
use of desensitising agents, varnishes and DBAs to reduce oversensitiveness
composite Rxs
prosthetic crown with pink porcelain in the region of the recession
removable pink gingival veneers
orthodontics
surgery - debride first to reduce bacterial load
95
recession - types of grafts
free soft tissue graft
pedicle gingival graft - leave tissue partially attached at donor site
- rotational flaps: laterally positioned flap or double papilla flap
- advanced flap: coronally advanced flap or semilunar coronally repositioned flap
= usually use split thickness flaps (not down to periosteum) as can't leave bare bone without periosteum - infection
96
when is grafting needed for recession?
is the recession progressing?
is the tooth tx planned for ortho care or prosthetic tx?
is there root sensitivity?
is there difficulty cleaning the root surface by the pt?
aesthetic concerns?
97
recession - CT graft
remove from elsewhere e.g. harvest from palate with 3-sided flap
can't place it uncovered as would get infected so suture a flap over it
can use the tunnelling technique
98
recession - FGG (free gingival graft)
if no surrounding keratinised tissue near
increase keratinised tissue around the teeth, implant or crown
remove from e.g. hard palate
99
recession - disadvantages of FGG
aesthetics not perfect
no pedicle - graft has no blood supply through the vessels during the first week
- increased risk of failure - necrosis
- graft needs to be v secure (not moving at all) to allow revascularisation
100
recession - coronally advanced flap with CT graft
split thickness pedicle flap
remove surface epithelium coronal to the pedicle flap to expose the underlying CT. Graft tissue
coronally reposition the pedicle flap and suture it over the recession defect
101
recession - double papilla rotational flap
incisions over papilla either side of the recession defect to raise a split thickness pedicle flap
pedicle flaps sutured together over the recession defect
102
recession - laterally repositioned pedicle flap
initial incision through the surface epithelium around the recession defect
surface epithelium dissected away to leave exposed CT on the mesial aspect which is now prepared to receive graft tissue
amount of tissue required is measured and a split thickness flap is raised on the distal aspect of the root surface
tissue laterally repositioned over the recession defect and the exposed CT on mesial side of root
suture, exposed CT at donor site left to heal by secondary intention
103
semilunar coronally repositioned flap
semilunar shape, brought down over recession defect
