Intra-oral Extra-Mucosal Fixation of Atrophic Mandible

INTRA-ORAL EXTRA-MUCOSAL FIXATION OF FRACTURES OF EDENTULOUS MANDIBLE

SOURCE

• International Journal of Oral-MaxilloFac Surg ,2013;42:460-463

Accepted for publication 13 Nov 2012 Available online 24 january 2013

AUTHORS

• A.Benech, M.Nicolotti, M.Brucoli, F.Arcuri• University of Eastern Piedmont, Novara,

Italy

• To improve is to change, to be perfect is to change often

• -Winston Churchill

INTRODUCTION• Atrophy of the mandible results in significant decrease in

bone mass

• Treatment of fractures in old patients with bone atrophy are characterized by high morbidity due to local and general factors

• Direct relationship between height of the bone at the fracture site and post-operative complications has been demonstrated

WHAT MAKES AN EDENTULOUS

MANDIBLE DIFFERENT

AGE CHANGES

• The bone is greatly reduced in size

• alveolar process is resorbed

• The mandibular canal and the mental foramen are closer to the alveolar border.

• The ramus is oblique , the angle measures 140° the neck of the condyle is more or less bent backward.

VARIATIONS OF IAN IN EDENTULOUS

MANDIBLE

• Type 1: Presence of one single trunk with no branching. • Type 2: Presence of a series of separate nerve branches • Type 3: Presence of a molar plexus. • Type 4: Presence of proximal and distal plexuses.

USG MEASUREMENT OF MANDIBULAR BLOOD

SUPPLY-

• arterial insufficiency may be an important pathogenic factor in mandible atrophy and tooth loss in the elderly.

• Journal of Oral and Maxillofacial SurgeryVol 63, Issue 1, January 2005, Pages 28–35

PURPOSE to evalute surgical outcomes

• Adequate mandibular restoration in terms of functionality and aesthetics

• To reduce the risk of damage to marginal mandibular nerve

• Reduction in operating time – shortened GA time

• Avoid unsightly scars

MATERIAL AND METHODS

• INCLUSION CRITERIA:-

• Bilateral fracture of atrophic mandibular body• Edentulism• Bone height < 20 mm

• EXCLUSION CRITERIA:-

• Patients were excluded if they had a previously treated or untreated fracture of mandible

• 13 patients (8 males , 5 females)• Mean age- 79 years• Range (72-86 years)• 11 patients treated by extra-mucosal

osteosynthesis• 2 patients by extra-oral ORIF

CAUSES

• Maximum height of mandibular body – 16 mm

• AT THE FRACTURE SITE• Avg height -11.5mm• Minimum height -8.5mm• Maximum height - 14mm

• time of surgical treatment after injury 1-6 days

• Discharge - second post-op day

RX

• Amox 875mg +125mg clavulanic acid

• Follow up - 40 days ,every week and 8th week (OPG)

• Plate removal under LA 1:100000 adrenaline

SURGICAL TECHNIQUE

• Osteosynthesis plate modelled on the mandibular arch

• Short bilateral mucosal incision(about 3 cm) is performed

• Subperiosteal dissection of lateral aspect of mandibular angles for insertion of the ends of the plate

• Fixed at the angle by single bi-cortical screw (2mm locking)

• Manual reduction of fracture

• Confirmed by intra-operative radiography

• If doubts remain, a small mucosal window is made to see the alignment of bone fragments

• Bone fragments are locked to the plate by one or two transmucosal plate at the symphysis and two additional screws at the angle

• Incisions sutured

• Operative time 35 -75 minutes

• Removal of the plate is on post-op week 9

• Angulated screwdriver after subperiosteal dissection at the terminal ends of the plate

• Anterior screws removed easily with appropriate screwdriver

COMPLICATIONS• One patient treated with extra-mucosal technique

(mycotic infection)

intolerable burning sensation

• Extra-oral technique( 4th week)

• Regression 6 days + pseudoarthrosis transient parasthesia of marginal mandibular

(spontaneous recovery in 5 months)

• 3 cases- Permenant Food debris in the holes of the plates and in between the plates and the gingival mucosa

• 2 cases- mucosal ulcerations of the lip corresponding to the upper edge of the lip

RESULTS• Radiography( 8 week) confirmed good bone

consolidation in 9 cases.plate removal on 9th week

• Compromised consolidation on left side after 8 weeks in one patient

• Bony union confirmed on reassesment in one month

Plate removal on 13th week No major intra-operative surgical complication

ELIMINATES•

EXTRA-ORAL APPROACH

MARGINAL MANDIBULAR UNSIGHTLY SCARS NERVE INJURY

COMPROMISE OF ADEQUATE BLOOD SUPPLY TO THE BONE AND MUCOSA

POTENTIAL CREATION OF SALIVARY FISTULAS

PROLONGED GENERAL ANAESTHESIA

ADVANTAGES

• Patient satisfaction- rapid positioning and removal of plate

• Resume soft diet with minimal discomfort post-operatively

• Shares the bio-mechanics of the masticatory forces bilaterally

• Less intra-op time than the submandibular approach (gold standard)

• Intra-operative radiography technique not mentioned

• Manipulation of fracture without direct vision and need for additional window visualize reduction

• Imperfect alignment?? Communted??

• Infection of surgical site- food debris

• severe atrophy- less screws-damage to nerve

CRITICAL APPRAISAL

CONCLUSION• Various authors have decribed the disadvantages

of extra-oral and trans-mucosal technique in atrophic mandible

• The main complications of extra-oral technique include injury to marginal mandibular nerve and unsightly scar formations

• Valid alternative to avoid these complications in patient with co-morbidities for whom extended GA time would give rise to complications

REFERENCES

An in vitro evaluation of miniplate fixation techniques for fractures of the atrophic edentulous mandible IJOMS, Volume 34, Issue 2, March 2005, Pages 174-177

Miniplate osteosynthesis for fractures of the edentulous mandible: A clinical study 1989–96 Journal of Cranio-Maxillofacial Surgery, Volume 26, Issue 6, December 1998, Pages 400-404

Spontaneous fracture of an atrophic edentulous mandible treated without fixation .British Journal of Oral Surgery, Volume 20, Issue 1, March 1982, Pages 22-30

The treatment of long standing bilateral fracture non- and mal-union in atrophic edentulous mandiblesInternational Journal of Oral Surgery, Volume 3, Issue 5, 1974, Pages 213-217