prosthodontic rehabilitation of mandibulectomy
TRANSCRIPT
Prosthodontic Rehabilitation Of Mandibulectomy Patients
Vinay Pavan Kumar K2nd year P G student
Dept of ProsthodonticsAECS Maaruti College of Dental Sciences
Classification of defects
Treatment
Surgical
Prosthodontic
Partially edentulous
Completely edentulous
Rehabilitation of mandibulectomy
patients
Diagnostic considerations
Classification of mandibular defects
Cantor and Curtis Class I -Radical
alveolectomy with preservation of mandibular continuity
Class II - Lateral resection of the mandible distal to the cuspid area
Firtell DN, Curtis TA, Removable partial denture design for the mandibular resection patient, J Prosthet Dent 1982; 48(4):437- 443
Class III - Lateral resection of the mandible to the midline
Class IV - Lateral bone graft and surgical reconstruction
Firtell DN, Curtis TA, Removable partial denture design for the mandibular resection patient, J Prosthet Dent 1982; 48(4):437- 443
Class V - Anterior bone graft and surgical reconstruction
Class VI - Anterior mandibular resection without surgical reconstruction
Firtell DN, Curtis TA, Removable partial denture design for the mandibular resection patient, J Prosthet Dent 1982; 48(4):437- 443
HCL (Boyd and colleagues classification)
H - lateral defects of any length up to midline including condyle
C - defects involve central segment containing 4 incisors and 2 canines
L - lateral defects excluding the condyle 3 lower case letters describe soft tissue
component o – no skin or mucosa s – skin m – mucosa sm – skin and mucosa
Maurer et al, Scope and limitations of methods of mandibular reconstruction: a long-term follow-up, Brit J Oral Maxillofacial Surgery 2010;28:100–104
Maurer et al, Scope and limitations of methods of mandibular reconstruction: a long-term follow-up, Brit J Oral Maxillofacial Surgery 2010;28:100–104
Urken et al Classification
Based on functional considerations caused by detachment of different muscle groups and difficulties with cosmetic restoration
C – condyle R – ramus B – body S – total symphysis SH – hemi-symphysis
Mehta RP, Deschler DG, Mandibular Reconstruction in 2004: An Analysis of Different Techniques, Current Opinion in Otolaryngology & Head and Neck Surgery, 2004;12:288-293.
Mehta RP, Deschler DG, Mandibular Reconstruction in 2004: An Analysis of Different Techniques, Current Opinion in Otolaryngology & Head and Neck Surgery, 2004;12:288-293.
Goals of Mandibular Reconstruction
Restore form and function
• Restore bony contour of native mandible
• Restoration of mastication
Deglutition Articulation Maintainance of the airway
Diagnostic considerations
Location and extent of the mandibular defect
Presence of remaining teeth
Degree of post mandibulectomy rotation and deviation
Available mouth opening
Functional limitation of the tongue
Location and extent of the mandibular defect
Loss of mandibular continuity/ without loss
Radical alveolectomy
- Loss of vertical ridge height and vestibular depth
- Reduction in stability
Location of defect Farther anterior the defect the more the disfiguring
(facial appearance)and functional disability
Anterior defects – symphyseal region – debilitating functionally – muscle attachments
Molar region defects – near normal mandibular function
Presence of remaining teeth
Determines the prognosis of rehabilitative therapy
Presence of teeth – better retention, stability and support
Mandibular incisors – abutments – indirect retention
Degree of post mandibulectomy rotation and deviation
Loss of mandibular continuity – deviation towards the defect
Vertical rotation of residual segment inferiorly
- suprahyoid muscles
- gravity Facial disfigurement, loss of occlusal contact, lack of saliva
control
Treatment for mandibular rotation and deviation
Restoration of continuity by osseous grafting
Physical therapy – stretching exercises, reposition training
Mandibular resection guidance prosthesis
- mandibular guide flange
- maxillary guidance ramp
Maxillary palatally positioned guidance ramp
When deviation is less severe
Not indicated in edentulous patients – lateral forces on complete dentures cannot be taken up
Available mouth opening
Trismus and scar/ fibrosis – post-operatively
Insert a stock mandibular impression tray in the mouth
Post surgical trismus - Stretching exercises, moist heat and analgesics
Functional limitation of the tongue
Wound closure limit tongue mobility
Speech, swallowing, mastication and control of food bolus and ability to control a removable prostheses
Posterior resection of tongue more debilitating than anterior tongue resection
Compromise of vestibular extensions
Implant rehabilitation
Grafted bone limited- length, diameter and number of implants less than ideal
Bone plates and screws to be removed
Surgical Reconstruction
The amount of remaining soft tissue
The size, extent and prognosis of the tumor
requiring resection
The age and general health of the patient
Location of the resection
Surgical reconstruction
Alloplastic implants
Vascularized free tissue grafts Fibular Free Flap Scapular Free Flap Iliac Crest Free Flap Radial Forearm Free Flap Double Flap Reconstruction
Prosthodontic rehabilitation of partially edentulous patients
Lateral discontinuity defects Lateral defects with anterior teeth present Arc of closure – angular
Altered cast impressions
Establish lingual extension of unresected side-
enhance stability and retention
Coverage of buccal shelf on unresected side –
maximize support
Extend impression into soft tissue on resected side
Mould the cheek and tongue from side to side
Clinical procedures Centric occlusion jaw relation record
Records with soft wax and minimum pressure
Force of contracture increases on unresected side – resected side moves downward out of occlusion
If severe trismus present – VD to be reduced to facilitate insertion of bolus b/w teeth
Defects with mandibular continuity
Anterior defects Patients with anterior inner table resections Anterior composite resections - mandibular
continuity is re-established by reconstructive surgery
patients have posterior teeth and extensive anterior edentulous area – Kennedy class IV partial denture
Posterior occlusion rarely altered
Anterior defects
Surgically restored anterior discontinuity defects – occlusal abnormalities because of graft contracture , inaccurate positioning of the residual mandibular segments.
Prostheses – enhance esthetics, support for lower lip and cheek, improved articulation of speech, control of saliva
Implant retained prosthesis
At least 10 mm of vertical bone Implants can be placed in residual bone or
free grafts Implants placed in the grafts 6- 9 months
later Removable overlay prosthesis preferred
for restoring the defects
Lateral defects
Posterior dentition remains on only one side of the arch
Conventional partial denture
Implant retained
Factors compromising function with complete dentures
Compromised retention, stability and support
Reduced saliva output – radiation / excision
Angular pathway of mandibular closure- dislodge the denture
Abnormal jaw relationships
Neuromuscular imbalance
Impressions
Preliminary impression - Maximum tissue coverage
Retention – close adaptation of the prosthesis with the bearing surface , extending lingual periphery maximally in the unresected side.
Polished surface accurately recorded – tongue retains the denture
Primary support area – buccal shelf on unresected side
Functional impression of polished surfaces of mandibular prosthesis
Centric registrations
Maxilla – wax rim widened on unresected side to account for the deviation of the mandible
Vertical dimension at rest difficult to determine
Evaluation of phonetics and closest speaking
space – best method for VD
Occlusal schemes
Non anatomic posterior teeth
Neutral zone
Mandibular posterior teeth – unresected side – buccal to crest of edentulous alveolus
Resected side – lingual to crest of edentulous ridge
Contour and support – lip and corner of the mouth – thickening the denture flange below the crest of the ridge
Mastication – non defect side
Processing, delivery and follow up
Patients monitored closely during post insertion period
Use of prosthesis for mastication deferred for a week
Implant retained and supported overlay denture
Osseointegrated implants – fabrication of well retained and stable overlay prosthesis
Minimum of 2 implants placed
15 mm apart to accommodate retention bar apparatus
Avinash C K A et al, Prosthetic management of partially resected dentulous mandible, Indian J Dent Adv 2011; 3 (1): 750-753
References
Beumer J, Curtis TA, Marunick MT, Maxillofacial rehabilitation Prosthodontic and surgical considerations,1st edition, lshiyaku Euro America publications, St Louis, 1996, Pp 113- 224
Taylor TT, Clinical maxillofacial prosthetics, 1st edition, Quintessence Publications, Illinois, 2000,
Pp 155- 188
Cantor R, Curtis TA, Prosthetic management of edentulous mandibulectomy patients -part II, Clinical procedures, J Prosthet Dent 1971;25:546-55
Firtell DN, Curtis TA, Removable partial denture design for the mandibular resection patient, J Prosthet Dent 1982; 48(4):437- 443
Maurer et al, Scope and limitations of methods of mandibular reconstruction: a long-term follow-up, Brit J Oral Maxillofacial Surgery 2010;28:100–104
Mehta RP, Deschler DG, Mandibular reconstruction in 2004: An analysis of different techniques, Current Opinion in Otolaryngology & Head and Neck Surgery, 2004;12:288-293.