MOCK SURGERY

SOFTWARES & RECENT ADVANCES

IN ORTHOGNATHIC SURGERY

Dr ARJUN SHENOY

INDEX

MOCK SURGERY

SOFTWARES IN ORTHOGNATHIC SURGERY

RECENT ADVANCES

CONCLUSION

MOCK SURGERY

Model Surgery

Analytic model surgery allow transfer of prescribed 3-D

movement directly to pt.

Allow surgeon to conform surgical movement by using

maxillary and mandibular cast

Provide quantitative data that are useful at the time of surgery

.

The geometrically precise information is then applied to patient by using specific measurement, reference point, splints

to reposition maxillofacial skeleton.

Model Surgery

Model Surgery - Double Jaw Surgery

Impressions

Face-bow record

Wax bite to record Pre surgical occlusion

Casts mounted on semi-adjustable

articulator

Mounting of maxillary cast with spacer

Blue plaster used for initial mounting

Jig positioned in articulator

Maxillary cast stabilized with putty

Initial mounting plaster removed

Maxillary impaction

Measurement of amount of impaction

Simulation of mandibular autorotation

Intermediate splint

Mandible advanced to desired position

Final splint fabricated

Final Splint

If the jig is not available, markings can be

made on the cast

Common Problems at this Stage

1. Interferences from the second molar teeth: arise from

the absence of bands on lower second molars or from

the presence of bands on the upper second molars

2. Incompatible canine widths: rarely a problem in Class II patients; Class III patients cannot simulate the postsurgical position

SOFTWARES IN ORTHOGNATHIC

SURGERY

NEMOCEPH

DOLPHIN SOFTWARE

NEMOCEPH

NEMOCEPH

INTEGRATE

•BITE REGISTRATION

DATA ASSORTMENT

•LASER SCANS OF DENTAL CAST

•CT SCAN

FINAL PRODUCT

•3D DENTAL + SKELETAL RECONSTRUCTION

VIRTUAL MERGING OF DETAILS

VIRTUAL PLANNING

VIRTUAL MOCK SURGERY

Online web meeting

(with assistance of software engineeers to

manipulate the scan in 3D with proprietary software)

TREATMENT PLAN-

Clinical findings

Dental cast assesment

SKELETAL REPOSITIONING

Mandibular autorotation

Saggital split osteotomies

Inverted osteotomies

Subapical osteotomies

Genioplasty

Repositioning of maxilla

(single or multiple segments)

Model surgery with a passive robot arm for

orthognathic surgery planning

greater 3-dimensional spatial accuracy-reliability-

precision.

Tamer Theodossy BDS, MSc, MFDSRCS(Eng) *and Mohammad Anwar Bamber PhD†

OPS

ORTHOGNATHIC POSITIONING SYSTEM:

INTRAOPERATIVE SYSTEM TO TRANSFER VIRTUAL SURGICAL

PLAN TO OPERATING FIELD DURING ORTHOGNATHIC SURGERY

Journal of Oral-MaxilloFac Surg 2013;71: 911-920

TECHNIQUE

IDENTIFICATION OF STABLE BONY LANDMARKS

Bilaterally

Landmarks placed on stable bone

Will not be repositioned during surgery

Bone thickness surveyed in CT data

USE OF LANDMARKS

Serve as reference points that will be used to transfer the

osteomized segment(s) to its final postoperative position

P.S- All reference points should be positioned so as to not

interfere with the fixation process

LANDMARK LOCATION

MAXILLA-

Above the osteotomy line

Above stable thick bone

MANDIBLE

Lateral and anterior surface of ramus

(percutaneous approach)

Medial aspect of coronoid ridges

IN GENIOPLASTY

Lateral to midline below the osteotomy

DIGITAL FABRICATION OF OCCLUSAL SPLINT

AND OPS

OCCLUSAL SPLINT

Splint ,the drilling and positioning guides are manufactured

by stereolithography and autoclaved for sterilization.

Designed with occlusal relationship in final position

Lateral attachment sites on right and left sides of the splint

Attachment for maxillary drlling guides

MAXILLARY DRILLING GUIDES

Bone borne footplates are designed with

anatomically contoured struts

Splint footplates attach precisely to lateral

attachment on occlusal splints (attach and

detach independently)

The bone borne footplates have two large

diameter openings

Designed to fit the metal drill guide(does not

rotate)

MAXILLARY POSITIONING GUIDES

Designed with maxilla in simulated final position

A bone borne positioning plate with small diameter that fit

over the previously determined reference landmark is

designed

Attached to occlusal splint and also secured to stable

maxillary bone using screws

Temporarily secures the Le-Fort 1 segment in its final

position before rigid skeletal fixation

DURING SURGERY

Occlusal splint is permenantly secured to

maxillary dentition in Le-Fort 1 cases

Temporarily secured to dentition in case of

multiple segment osteotomies, double jaw cases

Maxilla exposed

Drilling guide attached

Two reference landmarks

drilled

IN MANDIBLE

Drilling and positioning of proximal segment is

done with similar concept

Assists in maintaining the proximal segment in AP

plane and condyle position during fixation

Prevents lateral torquing of condyles

Precise repositioning of large advancements

STEREOLITHOGRAPHY

Stereolithography skulls

3D PRINTER

3D PHOTOGRAPHY

CONCLUSION

In order for patients to receive state-of-art care when

correcting their deformities, the orthognathic team must be able to

Correctly diagnose existing deformities.

Establish an appropriate treatment plan.

Execute the recommended treatment.

Dentofacial deformities – epker vol 1

Orthognathic surgery – Fonseca vol2

Text book of maxillofacial surgery- Peter ward booth –vol 2

Cephalometrics for orthognathic surgery – j. oral surgery

vol 36 apr 1978

Science Direct

Essential of orthognathic surgery – Reyenke

REFERENCES