PRE PROSTHETIC SURGERY

INTRODUCTION

    Definition: Pre Prosthetic Surgery (GPT 8): The surgical procedure designed to facilitate

fabrication of prosthesis or to improve the prognosis of prosthodontic care.

The majority of patients who require prosthodontic treatment will not require surgical

intervention prior to commencement of their prosthodontics. For many others, however, a

thorough and comprehensive examination, diagnosis and treatment plan will reveal that surgical

intervention can improve the prognosis for the case. Consideration of pre-prosthetic surgery is

one of numerous methods by which a patient’s clinical presentation may be advantageously

altered.

As a general "rule of thumb" the best procedure to consider is the least invasive process

that will produce clinical success. This may mean that it could be a disservice to the patient to

perform surgery when a non-surgical method could be used. It is likewise a disservice to fail to

consider and perform surgery when a non-surgical approach will produce a less than satisfactory

result.

REVIEW OF LITERATURE

1853: Willard stressed the importance of mouth preparation for complete dentures

1876: Beers advocated excision of alveolus after tooth extraction

1935: Kazanjian described a technique. for vestibular deepening

1944: Lisowski introduced tracing instrument to study the morphological changes

following teeth extraction

1951: Mathis & Cooley suggested surgical technique for lowering the mental foramen.

1957: Atwood radio graphically estimated the alveolar ridge resorption following teeth

loss.

1960: Sobolik brought out the effects of constant and intermittent pressure over the

residual ridge.

1965: Obweseger – published contemporary review of indications of soft tissue

reconstruction in the vestibule and floor of the mouth.

1976: Canzona experimented mandibular augmentation

1981: Samit et al described interpositional osteotomy and mandibular vestibuloplasty

1982: Kent advocated the use of hydroxyl apatite for ridge augmentation

1984: Indersano described a technique of open sub mucosal vestibuloplasty

OBJECTIVES

The two main goals of Preprosthetic surgery for completely edentulous arch are:

Provision of a comfortable tissue foundation to support the denture

Enlargement of the denture bearing area in attempt to provide stability for a denture.

The objectives of Pre Prosthetic surgery in partially edentulous arch are:

Restoration of the best masticatory function possible

Restoration or improvement of dental and facial esthetics.

INDICATIONS

Correcting conditions that preclude optimal prosthetic function

Localised/ generalised hyperplastic replacement of resorbed ridges

Epulis fissuratum

Papillomatosis

Unfavorably located frenular attachments

Pendulous maxillary tuberosities

Bony prominences, undercuts, and ridges

Discrepancies in jaw size relationships

Pressure on mental foramen

Enlargement of denture bearing area(s)

Vestibuloplasty

Ridge augmentation

Ridge preservation procedures

Supra mucosal vital root retention

Sub mucosal vital root retention

Root cone implants

Essential features of a denture bearing area

The denture bearing area should have following features:

Alveolar processes should be as large as possible and of the proper configuration.

Ideal ridge- Criteria for an ideal residual ridge (Goodsell- 1955)

1. Adequate bony support

2. Adequate soft tissue coverage

3. No undercuts & protuberances

4. No sharp ridges

5. Adequate vestibular depth

6. No scar bands

7. No high attachments of muscle bands/Freni that dislodges denture during

function

8. Satisfactory relationship of maxilla to mandible

9. No soft tissue folds, redundancies or hypertrophies

10. Free of neoplasm

According to Heartwell: Characteristics of this ideal form which provide for maximum

support and stability and minimum interference with function are:

Ridges are broad and flat with vertical height (minimum of 5mm)

provided by nearly parallel, non undercut, bony walls.

A firm, resilient mucosal covering with nicely shaped buccal and lingual

sulci which are uninterrupted by frenae,scars or redundant tissue folds.

An inter-arch distance (minimum 16 to 18mm) and relationship which

allows room for the denture and its components.

Proper jaw relationship should occur in anteroposterior, lateral and vertical

dimensions.

Adequate attached keratinized mucosa should be in present in primary denture bearing

area.

Adequate bone support for denture. Adequate vestibular depth.

No excessive muscle fibres or frena should be present , which can mobilize the periphery

of prosthesis during function

No evidence of intra- or extra- oral pathological conditions.

No bony or soft tissue protuberances or undercuts should be present.

PATIENT’S EVALUATION

     Before any surgical or prosthetic treatment, a thorough evaluation outlining problems to

be solved and a detailed treatment plan should be developed.

History: Patient’s chief complaint, expectations, esthetics, functional goals, psychological

factors, patient’s surgical risk status must be reviewed.

Physical Examination:

– Evaluation of supporting bone by

Visual inspection

Palpation

Radiographic examination

Articulated diagnostic casts

– Evaluation of supporting soft tissues for

Presence of inflammation

Quality of tissues

Depth of the vestibule

Frenal & muscle attachments

Treatment plan

Non surgical

Surgical

Combination of these

NONSURGICAL METHODS :

Rest for Denture Supporting Tissue

Removal of old denture should be done from the mouth usually 48-

72hours before taking impression.

Use the tissue conditioning material inside the old denture.

Rinse the mouth daily with a saline solution frequently.

Regular massage of denture bearing mucosa should be done with finger or

soft tooth brush which stimulates the mucosa to improve blood circulation

and enhances keratinisation.

Correction of Vertical Dimension of Occlusion in Old Prosthesis

An attempt can be made to restore an optimal vertical dimension of

occlusion to the old denture by using an interim resilient lining material.

This enables the dentist to know the amount of vertical facial

support that patient can tolerate and brings back the displaced tissue to

their original form.

Nutritional Care of Patient

Good nutritional program comprising of all essential nutrients must be

emphasized for each edentulous patient, specially for geriatric patient

because:

- Metabolic and masticatory efficiency is decreased in edentulous

patients due to decreased food intake.

Oral signs of nutrient deficiencies:

Protein: decreased salivary flow, enlarged parotid glands.

Vitamin B Complex, Iron & Proteins: Lips show cheilosis, angular scars,

angular stomatitis & inflammation.

Conditioning the Patient’s Musculature

Jaw exercises are used like:

- side to side movements

- protrusive and retrusive movements

- opening and closing of the mouth

to relax the muscles of the mastication and strengthen their coordination.

These also prepare the patient psychologically for prosthetic service.

SURGICAL METHODS

Before surgery certain investigations are required such as:

Routine blood examination like – TLC, DLC, Hb%, ESR, BT,CT

Blood sugar level

Throat swab culture

Allergic tests

Chest X-ray

CLASSIFICATION

Hard tissue surgery

Resective

Augmentation

Soft tissue surgery

Resective

Ridge extension

Miscellaneous

Nerve relocation

Sinus grafting

Tissue relocation

SOFT TISSUE PROCEDURES:

RESECTIVE SURGERIES

HYPERPLASTIC RIDGE

Also known as flabby ridge, it is mobile. There is marked fibrosis, inflammation and

resorption of underlying bones.

Causes

Inadequate rest to the denture bearing area.

Various forces to which the supporting tissues are subjected e.g. natural lower teeth

opposing the upper denture.

Excessive force on limited segments of the dental arches, due to lack of balancing

contacts in eccentric jaw position.

Trauma from denture wearing

Changes in the alveolar socket after extraction.

Treatment

Prevent the causative factor.

If this type of ridge is present in the maxillary anterior region, it is generally

removed surgically.

A satisfactory denture can be made on flabby ridge by using special impression

technique.

Surgical excision of hyperplastic soft tissue can be done to improve the stability and

support to denture and to minimize the alveolar ridge resorption.

o Simple excision :If sulcus depth is adequate

o Excision & alveoloplasty

o Subsequent vestibuloplasty

o Sclerosing (Laskin-1970) If excessive mobile tissues with acceptable

ridge contour with sclerosing agent Sodium Mohurrate

If there is excessive alveolar ridge resorption, bone graft or alloplastic material such

as hydroxyapatite can be used to improve the contour of the alveolar ridge.

EPULIS FISSURATUM

It is irritational fibrous growth of mucosa around the borders of the denture.

Causes Denture irritation due to

o Allergy or reaction to dental material

o Ill fitting denture

o Faulty denture construction

o Progressive resorption

Clinical features

o Continuous mucous fold b/w denture and alveolar process

o Lobulated / Bifid

Treatment

o Keep the denture out from the patient’s mouth to provide rest to the irritated

mucosa.

o Placement of soft liner

o Conventional surgery

Single mass - Simple excision

Multiple - Excision of the complete area

o Electrosurgery

o Surgical splint : Application of surgical stent helps in margin fixation at

desired position

o Full thickness graft - Prevents relapse

FIBROUS HYPERPLASIA

Fibrous hyperplasia of maxillary tuberosity

Causes - Pre existing periodontal disease of molars

Appears as avascular dense tissues at the tuberosity

Bony enlargements can be seen in radiographs

Treatment

– Surgical excision

Elliptical incision

Removal of the elliptic portion

Sub mucosal undermining

Suturing

Fibrous Hyperplasia: Retromolar pad

Causes - Impingement of maxillary molars and long standing irritation over the pad

Prevents posterior extension of mandibular denture

Treatment

– Surgical excision

Wedge incision

Thinning of the flap

Closure

– Complication

Lingual nerve paresthesia

Hyperplastic palatal mucosa

Usually seen on the palatal aspect of maxillary molars

Appears as firm, non tender with undercuts

Causes mechanical interference in denture construction and insertion.

It also results into the narrowing of palatal vault and interferes with speech

Treatment

– Simple excision

o Sub mucosal dissection

– Sloughing due to severing of palatal blood supply

o Stent to be placed for:

– Patient comfort

– Better dietary intake

o Avoid damage to the greater palatine nerve and vessels.

Papillary palatal hyperplasia (Palatal papillomatosis)

Hyperplastic papillary enlargement of tissues

Caused due to:

– Poor oral hygiene

– Continuous wearing of ill fitting dentures

– Candida infection

Treatment

– Electrosurgical excision

Impaired healing

– Muco abrasion technique

Islands of epithelium acts at growth centre

Papilla removed by:

– Sharp bony files

– Dermabrasion brushes

– Relining of dentures by soft liners

HYPERTROPHIC LABIAL FRENUM

Irritation by frenal notch in the denture flange

Treatment

– Relieving the frenal notch

Unesthetic appearance

Mid line fracture of denture

Inadequate border seal during impression making

May dislodge the denture

May create discomfort and ulceration

– Surgical excision

Frenectomy – Excision of frenum

Frenoplasty

– Z-plasty

– Localized vestibuloplasty with secondary epithelialization,

– Localized supraperiosteal dissection removing the fibrous

attachment.

Other frenal conditions affecting denture performance:

Abnormal lingual frenum

High / Prominent buccal frenum

– Affects stability of denture

– Tongue tie & speech impairment

– Poor border seal

Treatment

– Simple excision

PAPILLOMATOSIS

It is chronic inflammation of denture bearing area. It is characterized by finger like

projections which are aggravated by microbial plaque and yeast on the fitting surface of

denture base due to poor oral hygiene.

Cause

It occurs if patient wears denture throughout 24hrs.

Treatment

o Maintenance of oral hygiene and rest to tissues.

o Antifungal therapy

o Surgical removal of papillary projections.

PENDULOUS MAXILLARY TUBEROSITIES

They may occur unilaterally or bilaterally and obliterate the inter-arch space. They

interfere with the denture construction.

Causes

o Formation of excessive soft tissues overlying the bone or

o Due to the excessive bone formation at the site of tuberosity

Determined by

Radiograph

Sharp probe under LA

Treatment – Surgical excision of excessive soft tissue is required to provide adequate inter-

arch space. (Majority of the tissue reduction should be done on the buccal

aspect instead of lingual aspect to reduce the risk of damaging the lingual

nerve and artery).

RIDGE EXTENSION SURGERIES

Compensates for alveolar atrophy

• Vestibuloplasty

• Secondary epithelialization procedures

• Zygomaticoplasty & Tuberoplasty

Repositions:

• Overlying mucosa

• Frenal attachments

• Muscle attachments

Advantages:

Large denture base area

More retention & stability

VESTIBULOPLASTY

This exposes the bone still present. Healing is by secondary epithelialization. Skin

or mucosal graft can be used. Complications are loss of sensation, sagging of chin and

hypotonia of circumoral muscles

Sub mucosal vestibuloplasty (Obwegeser-1951)

Indications

– Small clinical ridge

– Sufficient healthy overlying mucosa

Procedure

– Infiltration anesthesia

– Midline vertical incision from nasal spine to incisive papilla

– Sub mucosal dissection & tunneling

– Closure & stabilization with stent

Secondary epithelialization procedures

Indications

– Excessive scarring of tissues

– Epulis fissuratum

– Insufficient height of bone with adequate mucosa

Kazanjian’s method

– Incision through mucosa of inner surface of lip

– Dissection of mucosa back to the crest of the ridge

– Supra periosteal dissection

– Suturing of flap to the periosteum

– Circumferential suturing of the rubber tube

– Secondary epithelialization of labial mucosa

Clarke’s technique

– Secondary epithelialization of alveolar ridge

– Procedure

Incision slightly labial to the ridge crest

Supra periosteal dissection & sulcus deepening

Undermining the lip mucosa till vermillion border

Mucosal flap held by circumferential sutures

Disadvantages

– 50% relapse in maxilla within 3 years

– 80-90% in mandible

Transpositional flap vestibuloplasty (Lip switch)

Indication sufficient alveolar height

sufficient vestibular depth

especially indicated in mandibular arch

Procedure - a split thickness mucosal flap is dissected from a periosteal flap. The

periosteal flap is used to cover the raw soft tissue surface and the mucosal flap to

cover the raw bony surface.

Epithelial graft vestibuloplasty

Uses grafts over exposed tissues

– Skin

– Mucosa

Increases

– Support

– Stability

– Retention of denture

Tissue graft vestibuloplasty

A. Partial thickness skin graft

Indications:

– Insufficient bone height

– Correction of relapse following epithelialization procedures

Advantages:

– Decreased wound contracture

– Rapid healing & early construction of dentures

Disadvantages:

– Grafted area will become dry & non-resilient

– Requires special instruments

B. Buccal mucosa graft

Advantages:

– Smooth transition b/w attached & free mucosa

– Vestibule remains displaceable and enhances denture retention

Disadvantages:

– Contracture

– Difficult to work with

– Chances of relapse is greater

C. Free palatal graft

Used in mandible

Tough, resistant & resists forces

Easy to obtain

Undergoes less contracture

Disadvantages:

– Healing of donor site is delayed and extremely painful

ZYGOMATICOPLASTY & TUBEROPLASTY

For increasing vestibular height in atrophic maxilla

Increases lateral stability of denture

Prevents anterior displacement of denture

LOWERING THE FLOOR OF THE MOUTH

As the alveolar bone is resorbed, the attachments of the mylohyoid and

genioglossus muscles may interfere with the lingual aspect of the denture.

HARD TISSUES SURGERIES

RESECTIVE SURGERIES

BONY SPICULES, PROMINENCES, UNDERCUTS & SHARP SPINY RIDGES

– Meyer’s classification

Saw tooth like

Razor like

Discrete spiny projections

Treatment

– Cortical alveoloplasty

Localized spicules & prominences

Incision

Trimming of bone & soft tissues

Irrigation & linear closure

– Inter cortical alveoloplasty

Prominent & irregular alveolar process

Removes undesirable undercuts

Removal of septa

Collapsing of labial / buccal cortical plates

ENLARGED TUBEROSITY (BONY ENLARGEMENT)

Enlargement may be:

– Buccal

– Palatal -- Unilateral

– Vertical -- Bilateral

– Combination

Radiographs to rule out:

– Molar impaction

– Pneumatized tuberosity

– Other bony lesions

Treatment

– Surgical excision

Crestal incision behind the tuberosity

Removal of excess bone

Sub mucosal dissection

Irrigation & closure

– Alveoloplasty

– Posterior maxillary osteotomy

Entrance into the sinus

PROMINENT / SHARP MYLOHYOID RIDGE

Maximum lingual extension of denture

– Counteract loss of tonicity of mylohyoid muscle

– Enhances stability & denture retention

Severe undercuts due to alveolar atrophy

Treatment

– Surgical excision

– Lingual sulcus deepening

Transposition of mylohyoid ridge & securing by circum mandibular

ligature wiring

PROMINENT GENIAL TUBERCLE

Constant source of mucosal irritation under the flange

Treatment

– Surgical reduction

Removal of tubercles and allowing reattachment

Removal of tubercles and repositioning of muscles by percutaneous

sutures

Sectioning of tubercles and trans positioning it along with the muscles to

the inferior border & securing it with ligature wiring

EXOSTOSES

Mandibular tori

– Single -- Multiple

– Unilateral -- Bilateral

Indications for removal:

– Interference in denture fabrication

– Constant ulceration under flanges

– Interferences in speech & deglutition

Treatment

– Surgical excision

Palatal Torus

– Indications for removal

Interference in the placement of PPS

Inadequate posterior extension of denture

Undercuts that trap food

Chronic inflammation of overlying mucosa

– Treatment

Surgical removal

– Complication

Oro-nasal fistula (Traumatic cleft palate)

CYSTS AND TUMORS

Odontogenic or Non odontogenic

Enucleation and marsupalisation

Excision or hemimandilectomy & RND

RIDGE AUGMENTATION PROCEDURES

Corrects the atrophic residues ridges surgically

Seibert’s classification of ridge defects

– Class-I defect

Facio lingual loss of tissue width with normal ridge height

– Class-II defect

Loss of ridge height with normal ridge width

– Class-III defect

Combination of loss in both directions

ONLAY BONE GRAFTING

Maxilla - Rib

Mandibular superior border - Rib or iliac crest

Mandibular inferior border - Rib

Direct Augmentation of Superior Border of Mandible

Procedure

– Infiltration anesthesia

– Incision from one retro molar pad to other

– Releasing incision for greater mobilization

– Lowering of mental nerve to prevent stretching

Autogenous rib

– 2 ribs of 15cm long

– Vertical scoring adaptation – 1st rib

– 4-6 mm pieces – 2nd rib

– Closure by continuous mattress suture

Iliac crest

– 3 ´ 8 cm block removed

– Cut into 1-1.5 cm pieces, contoured & adapted

– Fastening with circum mandibular wiring

– Packing of cancellous bone into the dead spaces

– Closure with continuous mattress suture

Disadvantage:

– Extensive surgical procedure

– Lip paresthesia

– 67-70% relapse in 3 years

Direct Augmentation of Atrophic Maxilla

Crestal incision from tuberosity to tuberosity

Autogenous rib contoured and fastened by intra osseous wiring

Cancellous chips filled in the dead space

Closure by continuous mattress suture

Advantages:

– Resorption less than that in mandible

Disadvantages:

– Postoperative sequestration

– Infection

Augmentation of Inferior Border of Mandible

First attempted by Canzona in 1975

Procedure:

Continuous sub mandibular incision from angle to angle

Autogenous rib 15-20 cm long

Removal of inner cortex, scoring & contouring

Fastening by transosseous wiring

Dead space filled with inner cortical pieces

Closure of wound in layers

Advantages:

– Non obliteration of vestibule

– Interim denture can be worn

– No changes in vertical dimension of occlusion

– Graft not subjected to direct masticatory stress.

Disadvantages:

– Extra oral scar

– Possibility of altering the facial appearance (lower 3rd)

INTERPOSITIONAL BONE GRAFTS

Augmentation with Interpositional Bone Grafts

Indication:

– Reasonable bone above the mandibular canal

Procedure:

– Horizontal osteotomy above the mandibular canal

– Corticocancellous struts placed in canine & molar region

– Cancellous chips placed in b/w the struts

– Closure

Advantages:

– Resorption less than 2mm in 1-5 years

OSTEOTOMY

Mandibular "visor" Osteotomy

Segmental Osteotomy for partially edentulous arch

Maxillary Osteotomy with advancement with classic Lefort I osteotomy

Horizontal osteotomy : An adequate vertical height of mandible must exist so that the

mandible can be cut horizontally. This cut is placed below the level of the mandibular canal

and mental foramen to avoid injury to the mandibular nerve.

Vertical or Visor Osteotomy

Advocated by Harle & modified by Peterson & Slade

Indications:

– Insufficient vertical height of bone in mandible

– Scope of performing horizontal osteotomy & interpositional graft is limited

– Minimum of 10mm width of bone is present

Procedure:

– Mandible split vertically

– Lingual section is elevated ( because the lingual section can be raised so it is

called as visor)& secured by trans osseous wiring

– Closure

AUGMENTATION WITH SYNTHETIC GRAFTS

Ceramic bone grafts

– Resorbable

β tri calcium phosphate

Porous hydroxyl apatite

Indications:

Bony defects in periodontal pockets

– Non resorbable

Non porous hydroxyl apatite

Indications:

Alveolar ridge atrophy

Hydroxyl apatite

Prototype of non resorbable ceramic bone substitute

– Calcium phosphate identical to:

Enamel

Cortical bone

– Available in 2 gm vial

Granular form

Application done after mixing with:

– Normal saline

– Venous blood

– Placed via syringe

Procedure:

– Vertical incision lateral to the labial frenum in maxilla

– Bilateral vertical incision anterior to mental foramen in mandible.

– Sub periosteal tunneling

– Placement of hydroxyl apatite slurry by a syringe

– Closure

– Complications

– Dehiscence & extrusion of particles

– Migration

– Abrasion of mucosa during tunneling causes extrusion of particles

– Infection

– Abnormal colour

– Mental nerve neuropathy

– Advantages:

– Highly biocompatible

– Local augmentation possible

– Metallic implants can be inserted later

– Simple office procedure under LA

RIDGE PRESERVATION PROCEDURES

SUPRA MUCOSAL VITAL ROOT RETENTION

– For over denture construction

– Increased

Proprioception

Masticatory efficiency

Retention & stability

No risk for rejection

Psychological benefits to patient

– Disadvantages

Caries & periodontal disease

Increased treatment costs

SUB MUCOSAL VITAL ROOT RETENTION

Reduction of roots 2 mm below crestal bone

Water tight closure of mucosa

– Criteria of teeth selection (Garver)

Teeth should have / be

– Not more than 1 mm horizontal mobility

– No infrabony pockets

– Healthy circum muco gingival tissues

– Vital & asymptomatic

Advantages

– Preservation of alveolar bone height

– Preservation of bony contour

– Enhanced denture retention

– Proprioception

– Decrease in loss of vertical face height

Complications

– Immediate:

Tissue dehiscence due to closure under tension

Immediate post surgical exposure of root requires RCT

Pressure pain

– Delayed:

Small dehiscence over individual roots

Fistula

ROOT CONE IMPLANTS

– Calcium phosphate group of biomaterials

Nonporous hydroxyl apatite

Tooth root analogues made of calcium phosphate group of biomaterials

Non porous hydroxyl apatite – frequently used

Procedure:

– Prophylactic removal of teeth to maintain alveolar height

– Solid cones of non porous HA implanted

– Elevation of muco periosteum & covering the implants

– Healing by secondary intention

Advantages:

– No inflammatory response induced

– Acts as a nidus for new bone growth

– Osseo integration occurs

– Height & width of ridge preserved

– Excellent biocompatibility

– Undergoes no resorption

– Binds chemically to bone

– DISTRACTION OSTEOGENESIS

Principle:

– Application of stress / tension induces osteogenesis

Devices

– Lead ‘R’ system by Chin

– Robinson inter Oss alveolar device

– ACE distraction device

Procedure:

– Horizontal osteotomy

– Insertion of distraction rod from crestal direction

– Fastening of transport plate on transport segment with bone screws

Advantages:

– No donor site morbidity involved

– Quality of bone formed ideal for implant placement

– Increased vascularity & cellularity

– Vertical graft stability

– Shorter treatment time ( 1 mm bone regenerated/day)

Disadvantages:

– VD compromised

– Unesthetic appearance

– Sufficient width for bone placement

– Frequent post op visits

MISCELLANEOUS

Nerve relocation

Problem is persistent discomfort under denture

Sinus grafting or Maxillary sinus lift

Success rate ranging from 75-100%

Indicated in atrophic maxilla for the placement of endosseous implants

Procedure: Incision parallel to alveolar crest and creation of a 2-3 mm window above the

sinus floor. In fracture of window , Dissection of sinus membrane ,Creation of space for graft

placement (Cancellous chips) ,Tears in membrane sealed with collagen tape and Closure

Tissue sclerosing with sclerosing agent Sodium morrhuate can produce fibrosis in soft

hyperplastic tissue

PRE PROSTHETIC SURGERY FOR SPECIFIC PROSTHESES

Over denture:

Selection of teeth that should be retained that offers broad support

Thorough oral prophylaxis

Endodontic therapy

– For lowering crown not ratio (1:5)

Periodontal therapy

– To attain optimal level of attachment of attached gingiva

Amalgam plugs / cast copings with studs / bar attachments for increased retention

Immediate dentures

Thorough oral prophylaxis reduces post surgical edema and infection

Teeth modification

– To avoid interferences in determining VD

Patient planned for single immediate denture requires:

– Restorations

– Crowns

– RPD

– Endodontic treatment (immediate over denture)

– Other hard & soft tissues procedures

Implants

CAT scans (Simplant software)

– Detailed evaluation of:

Alveolar contour

Neurovascular positions

Sinus anatomy

Path of insertion of Zygomatic implants

– Information regarding bone volume & quality

– Fabrication of surgical stent

PREPROSTHETIC SURGERY FOR PARTIALLY EDENTULOUS ARCH

Extraction with alveolectomy

Removal of residual roots

Impacted & malposed teeth

Cysts and tumours

Exostoses & tori

Hyperplastic tissue

Muscle and freni attachments

Bony spines & knife edge ridges

Polyps, papillomas & traumatic hemangioma

Hyperkeratoses, Erythroplasia, and Ulcerations

Dentofacial deformity

Osseointegrated devices

Augmentation of alveolar bone

Periodontal surgeries

Crown lengthening surgeries

PREPROSTHETIC CONSIDERATIONS IN MAXILLOFACIAL SURGERIES

Team approach

Never cut interdentally , it can jeopardize adjacent tooth rather cut intradentally.

More conservative

Modification of prosthesis design

Ridge relationship discrepancies by orthognathic surgeries. For maxillary advancement

Lefort I osteotomy and for mandibular advancement and retrusion sagittal split osteotomy

is performed.

POST OPERATIVE VISIT

Diet – Soft diet wherever indicated, nutrient rich diet must be advocated.

Medication- analgesics and antibiotics

Oral irrigation during checkups

Rest

Splint and oral fixation wherever indicated

CONCLUSION

When severe bony atrophy exists, treatment must be directed at correction of the bony deficiency

and alteration of the associated soft tissue. When adequate bony tissue remains, improvement of

the denture-bearing area may be accomplished either by directly treating the bony deficiency or

by compensating for it with soft tissue surgery. The patient's health status must be carefully

evaluated, along with the ability and willingness to undergo these procedures including possible

long periods without dentures during healing phases.

REFERENCES:

1. Mandibular Cortical Bone Graft Part 2: Surgical Technique, Applications, and Morbidity;

Compendium • May 2007;28(5):274-281

2. Williamson RA. Rehabilitation of the resorbed maxilla and mandible using autogenous

bone grafts and osseointegrated implants. Int J Oral Maxillofac Implants. 1996;11:476-488.

3. Atwood DA. Bone loss of edentulous alveolar ridges. J Prosthet Dent 1971; 26: 266-271.

4. Wise M D. Stability of gingival crest after surgery and before anterior crown placement. J

Prosthet Dent 1985; 53: 20-23.