Upload
hashifvc-ali
View
224
Download
0
Embed Size (px)
7/31/2019 Abhi Prostho
1/60
Presented by,Abhi AIV BDS (Part II)
Annoor dental college
7/31/2019 Abhi Prostho
2/60
INTRODUCTION
A significant number of prtients can neverbe made to use dentures effectivelybecause of bone atrophy,soft tissuehypertrophy or localized soft and hard
tissue problems or all of them.various treatment methods to improvepatients denture foundation and ridgerelations are:
NonsurgicalSurgical
Combination of both
7/31/2019 Abhi Prostho
3/60
Nonsurgical methods
Rest for denture supporting tissues
Occlusal correction of the old
prosthesis Good nutrition
Conditioning of the patientsmusculature
7/31/2019 Abhi Prostho
4/60
1. Adequate bone support.2. Adequate firm soft tissue coverage.3. No bony or soft tissue undercut or prominences.4. No sharp ridges.
5. No high muscle or frenal attachments.6. No presence of peripheral fibrous tissue bands to
prevent proper seating.7. No soft tissue hypertrophies on the ridges or in
the sulci.
8. No intraoral or extraoral pathology.9. Proper alveolar ridge relationship in all threeplanes.
Characteristic of idealdenture bearing area
7/31/2019 Abhi Prostho
5/60
Preprosthetic surgery.
Preprosthetic surgery is carriedout to reform/redesign soft /hard tissues by eliminating
biological hinderness to receivecomfortable & stable prosthesis.
7/31/2019 Abhi Prostho
6/60
Aims of preprosthetic surgery
1.To provide adequate bony tissue support forthe placement of rpd /cd.
2. Provide adequate soft tissue support,optimum vestibular depth.
3. Elimination of the pre-existing bonydeformities eg. Tori, promoinent mylohyoidridge,genial tubercle.
4. Correction of mandibular and maxillary ridgerelationship.
5. Elimination of preexisting deformities.eg.epulis,flabby ridges, hyperplastic tissues.6. Relocation of frenal or muscle attachments.7. Relocation of mental nerve.8. Establishment of correct vestibular depth.
7/31/2019 Abhi Prostho
7/60
Preprosthetic surgical procedures .
Alveolar ridge correction
Alveolar ridge extension
Alveolar ridgeaugmentation.
7/31/2019 Abhi Prostho
8/60
Alveolar ridge correction
Bony surgeries.
Labial alveolectomy.
Primary alveoplasty. Secondary alveoloplasty.
Excision of tori.
Reduction of genial tubercle.
Reduction of mylohyoid ridges.
Maxillary tuberosity reduction
7/31/2019 Abhi Prostho
9/60
Soft tissue surgeries:
Removal of redundant crestal softtissue.
Frenectomy labial & lingual.
Excision of epulis fissuratum &
palatal hyperplasia.
7/31/2019 Abhi Prostho
10/60
ALVEOLECTOMY.
Surgical removal or trimming of thealveolar process.
Trimming done with roungeur or round
bur and smoothened with bone file.
Use in the presence of sharp margins atinterseptal or labiobuccal alveolar ridge.
Too much bone loss will result in poordenture base.
7/31/2019 Abhi Prostho
11/60
Single tooth alveolectomy
7/31/2019 Abhi Prostho
12/60
Simple Alveoloplasty
Refers to surgical recontouring of thealveolar process.
Primary alveoloplasty always done at the
time of multiple extraction or singleextraction.
Minimum amount of alveolar boneresorption occurs if after simple
extraction ,digital compression of theaqlveolar cortices done immediately.
7/31/2019 Abhi Prostho
13/60
Intraseptal alveoloplastydeansalveloplasty with repositioning oflabial cortical bone. Used in maxilla. Used to reduce gross maxillary overjet. To reduce the volume of Cancellous bone ,
maintaining stress bearing cortical bone intact. Not require for raising mucoperiosteal flap. Carried following extraction of anterior teeth
immediately. Maintain periosteal attachment to the labial plate
of bone. It will reduce buccal undercut or labial
prominence without reducing the height ofresidual alveolar ridge. Best long time result. Indicated in cases , in which the adequate bone
height exists.
7/31/2019 Abhi Prostho
14/60
7/31/2019 Abhi Prostho
15/60
Indications 1.Multiple extraction 2.Early initial post extraction period. Steps 1.removal of bone followed by
2.repositioning of the labial corttical bone. Technique Teeth should be extracted avoiding trauma to the
labial cortex. Interdental septal bone is cut from canine to
canine region with the straight fissure bur attached
to surgical handpiece or with rongeur. With the same bur ,vertical cuts are made only in
the labial cortex at distal end of the canineextraction sockets bilaterally without perforation ofthe labial mucosa in the deans technique.
7/31/2019 Abhi Prostho
16/60
With periosteal elevator /osteotome placedin the base of the canine socketbilaterally, labial cortex is fractured.
Digital pressure is used to compress the
fractured labial cortex into the palataldirection.
Labial and palatal plate will come intoapproximation with each other.
Interrupted continous suturing is carried
out.
7/31/2019 Abhi Prostho
17/60
Obwegessers modification for
interseptal alveoloplasty
Indication Gross max.overjet.( when compression of the
labial cortex is not sufficient) After cutting the interseptal bone ,an inverted
cone vulcanite bur is used to widen the socket. With small bur ,horizontal cuts are made at the
base of the extraction socket in the labial andpalatal cortices.
Vertical cuts then made bilaterally in both thelabial and palatal cortices in the area distal to the
canine socket. With digital pressure,both the labial and palatal
cortices are compressed together and sutures aregiven.
Immediate denture delivery is planned ,used as atemplate to check for any pressure points.
7/31/2019 Abhi Prostho
18/60
Alveoloplasty with post extractionhealing
Crestal incision is taken not to tearthe mucoperiosteal flap, but thereflection
Side ways separation with theperiosteal elevator will help thesmooth reflection.
Sharp areas or large undercutsshould be trimmed with rongeur.And suturing done.
7/31/2019 Abhi Prostho
19/60
Elimination of unfavourableundercut
Usually done in the mandibularlingual aspect (genial tubercle ,sharp mylohyoid ridge prominence.)
Seen in patients wearing olddentures, due to resorption over theyears,the denture become unstable
7/31/2019 Abhi Prostho
20/60
Reduction /resection of the genialtubercle
Are bony attachments of genioglossus muscle.
Are seen on the crestal level on the lingualaspect.
7/31/2019 Abhi Prostho
21/60
Technique
Crestal incision is made from the lowercanine to canine region , after infilterationof the LA.
No reflection of flap done on the labial
side. Full thickness flap is reflected to expose
the genial tubercle. Excision of tubercle is done by rotary
instruments . Smoothening can be done by a bone file. Irrigation should be done before suturing.
7/31/2019 Abhi Prostho
22/60
Reduction of mylohyoid ridges
Done with IFAN block. Crestal incision taken in the posterior ridge region. Mucoperiosteal flap reflected on the lingual side to
expose the medial surface of the mandible at themylohyoid ridge region.
Tissue from the floor of the mouth and lingualmucoperiostium are protected by inserting the flatblade of the tongue depressor .
The reduction of the mylohyoid ridge is carried withosteotome or round bur ,after dissecting mylohyoidfibres away.
Bone is smoothened with bone file. Soft tissue flap is returned back and the complete
lingual vestibule checked with digital pressure for anysharp areas.
After complete smoothening sutures are given.
7/31/2019 Abhi Prostho
23/60
Excision of tori
Indications Large torus ,filling the palatal vault. Large torus extending beyond the
postdam area. Ulceration or traumatisation or
hyperkeratinisation of the overlyingmucosa.
Deep bony undercut.
Interference with function. Psychological consideration. Food lodgement.
7/31/2019 Abhi Prostho
24/60
7/31/2019 Abhi Prostho
25/60
Under LA ( bilateral grater palatine and incisivenerve block)
A-P linear incision in the midline of the palate. Y shaped releasing incision at one or both the ends
of the incision.
Two mucoperiosteal flaps raised with periostealelevator from th midline sideways. Retraction sutures placed on both the flaps to
minimize the exposure. Division of the torus into the multiple segments
should be done with the bur.
Small pieces removed with chisel and mallet. Conyinous over and under type suturing using fine
absorbable suture material. Prefabricated acrylic stent or splint or iodoform pack
can be given to prevent heamatoma.
Technique
7/31/2019 Abhi Prostho
26/60
Mandibular tori removal.
Technique
IFAN block is given.
Incision over alveolar ridge in lower
premolar region. Mucoperiostral flap is raised
Make a purchase point or groove with buron medial aspect of the tporus.
Cleavage taken with a osteotome. Smoothen with roud bur or bone file.
Irrigatre band suture.
7/31/2019 Abhi Prostho
27/60
Maxillary tuberosity reduction andexostosis removal
Technique
Under infilteration or PSA nerve &GPN block.
Crestal elliptical incisions fromtuberosity to premolar area.
Periostium is reflected and tissue
present b/w the crestal incisionremoved with chisel mallet or bur.
Flap is sutured and stent is placed.
7/31/2019 Abhi Prostho
28/60
Soft tissue surgeries
Removal of redundant crestal soft tissue - eg .enlarged tuberosity, enlarged retromolar pad.
Denture granuloma or hyperplasia. To reduce this elliptical incision taken on either
sides of the tissue . Excision of epulis fissuratum. Sharp excision Electrocauterisation Cryosurgery
Laser excision Palatal papillary hyperplasia. Supraperiosteal excision.
7/31/2019 Abhi Prostho
29/60
Frenectomy
Indications
High attachment of frenum.
Ulceration at the frenal attachment a due to overuseof the denture
TECHNIQUE
Crosssdiamond excision.
Base of the frenum at the alveolar crest is grasped with
the hemostat and incision is taken below and above the
hemostat.Surgical defect created by excision of fibrous bands.
Z plasty procedure can be done.
7/31/2019 Abhi Prostho
30/60
Lingual frenectomy
Indication
Tongue tie
Technique
Bilateral lingual nerve blockSubmucosal dissection done oneither side .Dissection of genioglossus muscle
and suture it.
7/31/2019 Abhi Prostho
31/60
Ridge extension procedure
Vestibuloblasty or sulcoplastyIt is a deepening procedure of vestibule.
Mandibular techniques
done on labial side done on lingual side labial vestibular procedure
transpositional flap vestibuloplasty orlip switch procedure
IndicationsUsed when patient has a bone ht of 15mm
or more in the ant region
7/31/2019 Abhi Prostho
32/60
Techniques
kazanjian technique (1924) oldest technique
use mucosal flap from the inner aspect of lowerlip.
Carried out in premolar to premolar region.
Procedure
submucosal dissection is done anddirected inferiorly to remove muscle andconnective tissue attachments.
Raised mucosal flap is adapted to thenew vestibule and
Suture is done
7/31/2019 Abhi Prostho
33/60
Godwin s modification (1947)
Mucosal incision in inner aspect of lip islonger than the proposed vestibular depth .
Labial periosteal margin is sutured to theincised lip mucosa.
Stent is placed.
7/31/2019 Abhi Prostho
34/60
7/31/2019 Abhi Prostho
35/60
Supraperiosteal flap on the inner aspect oflip leaves a raw surface on the bonecovering the inner lips surface .
Incision started labial to the crest
Supraperiosteal dissection is done along thelabial surface till the vestibular depth.
Edge of the mobilized flap is pushed intothe new vestibular area and held in positionby sutures .
Alveolar bone is covered by periosteallayer.
7/31/2019 Abhi Prostho
36/60
Similar to clarks method except the area ofalveolar bone with its periosteal attachment
covered with split thickness graft. Advantages
Covers the bone and ensures fast healing
Less bone loss and scarring .
Obwegessers modification
7/31/2019 Abhi Prostho
37/60
Lingual vestibuloplasty
Indication
In case where mylohyoid and genioglossus closeto the alveolar ridge.
Trauners technique
Incision is done from 2nd molar to 2nd premolarregion
Supraperiosteal dissection is done
Instrument paseed below mylohyoid muscle andseparate it from bony attachment.
Fixation of mylohyoid muscle to new desiredvestibular depth by sutures.
7/31/2019 Abhi Prostho
38/60
Here mylohyoid muscle superficaial fibreesof genioglossus muscle pushed inferiorly.
Rubbertubing placed in the lingual vestibuleand flap is held in position by sutures
Caldwells technique
7/31/2019 Abhi Prostho
39/60
Obwegessers technique
Lingual vestibuloplasty + buccalvestibuloplasty
Edges of buccal and lingual flaps areraised and sutured below the inferiorborder of the mandible.
Skin graft is placed over the entirealveolar ridge.
Acrylic stent or denture placed and fixedto mandible with circummandibularwiring.
7/31/2019 Abhi Prostho
40/60
Submucosal vestibuloplasty techniqueIndication Shallow vestibular depth with good
underlying bone height and contour.Technique Vertical midline incision is made in the
labial vestibule. Supraperiosteal tunnel from one premolar
to other . Intervening submucosal tissue excised or
repositioned superiorly.
7/31/2019 Abhi Prostho
41/60
Procedure involves surgical creating pockets in themax,mattress and pyriform aperture region helps inthe denture extension into the pockets.
Intraoral incision is taken just above the attachedgingiva from one maxillary buttress to the other
buttress. Supraperiosteal dissection is performed to create two
pockets on either side of pyriform aperture. Dissection is extended superiorly to the level of
attachment of the levator anguli oris. Also continued in the midline upto the base of the
pyriform aperture. Impression is taken with the impression compound. Labial flanges of the dentures then covered with split
thickness skin graft. Bilateral circumzygomatic wires and pyriform margin
wires used to stabilize the denture.
Max.pocket inlay vestibuloplasty (obwegesser)
7/31/2019 Abhi Prostho
42/60
Patients with severe mandibular atrophic ridges. Complain of pain after wearing denture because of
superior position of the mental neurovascular bundle. Repositioning of the mental nerve should be done.
A crestal incision is taken with buccal releasing incision inthe region of premolars. Mucoperiosteal flap is reflected inferiorly to locate the
nerve. Dissection below the foramen till the inferior border of
the mandible should be done and the nerve is freedlightly and held with hook upward.
Bony groove is cut below the mental foramen,only in thebuccal cortex.
Nerve is positioned inferiorly and secured in place withthe gelfoam and flaps is sutured.
Mental nerve transposition
7/31/2019 Abhi Prostho
43/60
Ridge augmentation procedures
Alveolar ridge resorption is soextreme that the alveolar bone iscompletely disappeared., in this
case vestibuloplasty is not done.
Two appointments are available
Augmentation of alveolar bone.
Place the implants.
7/31/2019 Abhi Prostho
44/60
Procedures
Mandibular augmentation
1. Superior border augmentation
Bone grafts
cartilage graft
alloplastic grafts
7/31/2019 Abhi Prostho
45/60
7/31/2019 Abhi Prostho
46/60
2.inferior border augmentation
bone grafts .cartilage grafts
7/31/2019 Abhi Prostho
47/60
3.interpositional or sand witch bonegrafts
Bone grafts
cartilage grafts
hydroxyapatite blocks
7/31/2019 Abhi Prostho
48/60
4. visor osteotomy5.onlay grafting autogenous
allogenous alloplasticB. maxillary augmentation. Onlay grafting Onlay grafting of alloplastic material Interpositional or sandwitch grafs Sinus lift procedure
7/31/2019 Abhi Prostho
49/60
Augmentation in combination withorthognathic surgery
mandibular osteotomy procedure maxillary osteotomy procedure
CombinationMaterials for augmentation of alveolar ridge autogenous grafts iliac crest rib graft
allogenic bone freeze dried cadaver bone. Alloplastic material Hydroxyapatite
7/31/2019 Abhi Prostho
50/60
Mandibular augmentation
Superior border grafting oraugmentation
Use 15 cm rib graft . Fixed to mandibvle with trans osseous
wiring of circum mandibular wiring.
Disadvantage
Donor site morbidity Continued resorption of grafted sites.
Soft tissue dehiscence or limitation.
7/31/2019 Abhi Prostho
51/60
Inferior border grafting It is indicated when the arch less than 5-
8 mm in height.Procedure Supraclavicular incision followed by
subplatysmal incision till the inferiorboredr of the mandible.
Freeze dried alloogenic cadaver mandible
is hollowed out and multiple perforationsmade into it and it is used as atray. It is then filled with autogenous
cancellous graft particles fixed to theinferior border with 2-0 vicryl sutures by
cicummandibular fixation
7/31/2019 Abhi Prostho
52/60
Interpositional bone grafting (sandwitch bone grafting)
Horizontal osteotomy is performed
Splitting is done and bone graft is graftedinto this gap
In mandible , autogenic or allogenic boneor hydroxyapatite grafts can be used.
Delivery of aplliance is delayed for 3-5months.
7/31/2019 Abhi Prostho
53/60
Onlay grafting
Used in case of inadequate width but adequateheight for the maxilla or mandible
Oldest technique
Onlay augmentation with hydroxyapatite isadvocated by obwegessor via submucosalvetibuloplasty technique.
After creating a tunnel via a midline a putty isformed of hydroxyapatite crystals is mixed withsaline or blood and is injected via syringe into the
submucosal tunnel. Solid or porous blocks of hydroxyl apatite is used. Split thickness ribgraft or iliac crest can be used.
7/31/2019 Abhi Prostho
54/60
Technique High vestibular incision is taken , mucoperiosteal flap is
reflected to expose the defect. Small perforations made in this external cortex by using
small round bur.
Grafting material is placed or mounted over the externalcortex.
Visor osteotomy To increase the height of mandibular ridge for denture
support. Consists of central splitting of the mandible in
buccolingual dimension and the superior positioning of thelingual section of mandible wired in position
Cancellous bone grafting material placed at the outercortex over the superior labial junction for improving thecontour.
7/31/2019 Abhi Prostho
55/60
Modified visor osteotomy Consists of splitting of the mandible
buccolingually by vertical osteotomy only in theposterior region and a horizontal osteotomy inthe anterior region.
Posterior lingual segments are then pushedsuperiorly on both sides. Anterior fragment is also pushed superiorly and
fixed with wires. Corticocancellous bone graft particles with
hydroxyapatite granules placed in the gap
between the superior , inferior and anteriorsegments.
7/31/2019 Abhi Prostho
56/60
Sinus lift procedure or sinus grafting Sinus lining at the floor of the mouth is lifted up
surgically and the bone graft is placed between thesinus lining and the inner aspect of the alveolarcrest or floor of the maxillary sinus in the posterior
maxilla.Totum was the first surgeon who used this
method.Materials used are autogenous bone allogenic bone. tricalcium phosphate hydroxyapatite. calcium phosphate. ceramics calcium deficient carbonate apatite from bovine
bone.
7/31/2019 Abhi Prostho
57/60
Technique Intraoral incision is taken on maxillary crest or
slightly on the palatal aspect with vertical incisionfrom canine to tuberosity area
Antrolateral wall of maxilla is exposed by reflecting
the mucoperiosteal flap Bony windows made with trap door type osteotomy ,
lateral and posterior to the caine fossa. 15 20 mm lomg inferior osteotomy cut placed
3mm above the sinus floor Anterior vertical cut parallel to the lateral nasal wall
and perpendicular to the horizontal osteotomy. Posterior vertical cut is at the maxillary tuberosity. Vertical cuts are joined superiorly by placing the
small bur holes placed at small intervals withoutcompleting the superior cut.
7/31/2019 Abhi Prostho
58/60
Trap door type of bony window is lifted upsuperiorly o expose the schineiderianmembrane.
Gap between lifted sinus membrane and
the floor is filled with graft material. One stage implant Coticocancellous iliac crest bone block Otherwise 6-9 months before implant
placement
7/31/2019 Abhi Prostho
59/60
Augmentation in combination withorthognathic surgery
1.anterior maxillary osteotomy. 2.total lefort osteotomy used along with
interpositioning of grafts. Limitation of augmentation technique 1.inadequate soft tissue coverage. 2.rejection of autografts.
3.dehiscence of overlying mucosa. 4. migration of graft material. 5..resorption of graft.
7/31/2019 Abhi Prostho
60/60
conclusion
Preprosthetic surgery offers a sigificant contributionin patients with bone atrophy,soft tissuehypertrophy or localized soft and hard tissueproblems or all of them.
Pre existing stuctures like frenal
attachments,exostosis,tori are insignificant whileteeth are present in the oral cavity. But these nonsignificant structures cause hindrences fordenture stability and resultant reducedmasticatory function after tooth loss.
Preprosthetic surgery plays an important role in
providing a better anatomic environment and tocreate proper supporting structures for dentureconstruction.