Computers in Ortho - DR G.S FINAL YEAR

7/28/2019 Computers in Ortho - DR G.S FINAL YEAR

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COMPUTERS IN ORTHODONTICS



•

The computer is basically an automaticelectronic machine that performscalculations or derives results based onthe data fed into it.

• A computer is capable of accepting data,performing operations acc. to instructionsand providing the results of theseoperations in comparatively shorterduration of time and with greateraccuracy.



• Orthodontists with their love for technolgy andminiaturization have not remained untouched.

• Orthodontic offices use computers for manypurposes ranging from administrativeapplications, clinical applications to researchapplications.



History of Information Technology & Systems

Four Basic Periods of Information Technology

• Pre mechanical• Mechanical• Electromechanical• Electronic



The Pre-mechanical Age: 3000 B.C. - 1450 A.D.

First Calculators: The Abacus



Alan Mathison Turing Father of Modern Computer Science

Concept of algorithm& computation:

The Turing machine

Designed one of thefirst electronic

programmable digitalcomputers:

THE COLOSSUS

British mathematician& cryptographer



The Electronic Age: 1940 - Present

• First Generation (1951-1958) - Punch Cards

•

Second Generation (1959-1963) –Transistors• Third Generation (1964-1979) -Integrated

Circuits

• Fourth Generation (1979-Present)



Classification Of Applications

1) Administrative applications

• Patient case records• Recall appointments• Accounts• Patient correspondence• Billing• Inventory lists• Prescription formats• Post-treatment instructions• Insurance claims• Referral information•

Missed appointment follow up.



2) Clinical applications

• Patient photographs & radiographs• Patient motivation• Appliance design using CAD CAMs• Growth predictions•

Visual treatment objectives• Generation of pre & post-treatment photographs• Survey information/epidemiological data• Presentations•

Continuing dental/ medical education• Literature reviews• Entertainment



3) Miscellaneous applications

• Survey information / epidemiological data• Presentations• Continuing dental / medical education• Literature reviews •

Entertainment



CAD / CAM

• CAD Computer AidedDesigning

• CAM

Computer AidedManufacturing

• Occlusal Splints• Planning Surgeries• Bone Implants• Restorations• Designing structures for

FEAnalysis• Appliances and equipment

Application of computers in orthodontics – Research sem1/sb/09-04



• Surface geometry of casts - scanned by 3Dlaser surface scanner

• Facial morphology – 3D triangular facets – connecting spatial coordinates – landmarks fromfrontal & lateral cephalograms

• 3D virtual image for surgical simulation

Application of computers in orthodontics – Research/Clinical / Manufacturing sem1/sb/09-04

Procedure for designing a splint



• 3D virtual image used to plan the amount anddirection of bone displacement – post surgically

• Surgical splint designed on this image

•

3D graphic image of surgical splint istransferred to a laser lithography unit forpolymerization

Application of computers in orthodontics – Research / Clinical / Manufacturing sem1/sb/09-04



CA D/CA M FA B RICA TION OF OCCLUSA LSPLINT FOR ORTHOGNA THIC SURGERY

LASER SCANNINGOF THE CAST

IMAGE OF CASTON MONITOR



IMAGES OF STUDY CASTS AND FACIALSKELETON COMBINED FOR SIMULATION



SAGITTAL SPLIT RAMUS OSTEOTOMYSIMULATED ON 3D IMAGE



CONTACT AREAS OF OCCLUSALSPLINT DRAWN FROM

COMPUTER IMAGE OF STUDY CAST

FINISHED 3D IMAGEOF

OCCLUSAL SPLINT



OCCLUSAL SPLINT POLYMERIZEDBY LASER LITHOGRAPHY UNIT



Bending Art System (B A S)

• Fischer - Brandies and Orthuber Wolfganginvented BAS in 1983

•

1st prototype of BAS manufactured in 1993• Components of BAS

1. Stereoscopic camera2. Personal computer and its software3. Arch wire bending device




Stereoscopic camera

• Stereoscopic camera consists of CCD whichcan be directly used in the patients mouth

•

Procedure

- SS measuring plates placed on the bracketslots & molar tubes- Mirror of camera moves two times forwardand backward- Scans using White light




Bending Art System (B A S)




Arch Wire Bending Component

• Three components

> Holding cone> Inner cone> Partial cone

Application of computers in orthodontics – Research / Manufacturing sem1/sb/09-04



- Round wire and Rectangular wire used

- SS, TMA or Ni-Ti wires

- Bending begins only after all bends aremanipulated

- Approximately takes 5 – 7 min




Advantages

• Precision arch wires• Rapid fabrication•

Fabricate full sizepassive arch wiresfor surgical cases

• T loop & L loopconstruction

• Utility arches made

Disadvantages

• Time required forthe insertion ofmeasuring plates &their identification

• Clinical judgment isstill vital

•

Steel wire easilydeformed




FUNDAMENTALS OF COMPUTERGRAPHICS

• GRAPHIC APPLICATIONS - Software

applications that convey informationpictorially

•

Information is displayed graphically on acathode ray tube (CRT) monitor or flatpanel display



Pixel•

The image space on amonitor is made of tinysquare picture elements,called pixels (using thecommon abbreviation"pix" for "picture“)

•

Arranged in the seriesof horizontal lines calledRaster lines



Graphic imagesBitmaps

• Digital images are stored in a matrix of rows &columns of pixel values

• Image-editing programs are designed to workprimarily with bitmapped images

• Corel Paint™, Microsoft Photo Editor™ andPhotoshop™ are examples of bitmap editingprograms.



Bitmapped image



RADIOGRAPHIC IMAGEACQUISITION



Denoptix

•

Digital radiographic technique which usesPhosphor imaging plates to capture and storeimages

Advantages

- Alternative to conventional film- Same machine and settings- No dark room required- Environment friendly- no heavy metal

wastage- Can be reused thousands of times

Application of computers in orthodontics – Clinical / Graphic sem1/sb/09-04

I gi g l



Imaging cycle

1.Load intraoral or panoramicimaging plate

2. Take X ray

3. Mount imaging plates in carousel 4. Place in scanner & Scan images

5. Erase imaging platesfor reuse

Image on computer



CEPHALOMETRIC APPLICATIONS



CEPHALOMETRIC APPLICATION WORKFLOW

» DIGITIZATION

» DISPLAY

» ANALYSIS

» TREATMENT PLANNING

» HARD COPY



DIGITIZATION•

Is the form by which analog information isconverted to digital form

2 methods used:

• A digitizing table or digitizer with finecross hairs, to locate landmarks &contours on radiographs manually. This istransmitted to computer & recorded for

various cephalometric determinations



MODE OF DIGITIZATION

• POINT MODE

discrete location of

individual landmarks



• STREAM MODE

a stream of co-ordinatedpairs are recorded asthe user traces the

radiographic contour



DIGICEPH

• IIT and AIIMS – NewDelhi

•

Computerised cephdigitisation

• Automatic analysis

• Plot superimposition

• 13 Ceph analysis

•

Ceph placed ondigitizer

•

Point mode used tomove cursor

• Stream mode to finish

• X – Y co-ordinates arerecorded and analysed




Digigraph• Introduced by Dolphin

imaging systems

•

Non radiographicsystem

•

Video imaging is alsopossible




The Digi-Graph work

station is about 5 feetlong, 3 feet wide and 7feet high.

The main cabinet containsthe electronic circuitry,and the patient sits nextto the cabinet in anadjustable chair similarto those used withcephalometers.



The head holder issuspended from a beam,

supported by a verticalcolumn attached to thecabinet.

Ear rods and forehead andposterior head pieces areused to minimize patientmovement.

ear rods can be removed sothat facial and intra-oralimages can be recorded

while the patient is sitting



A light box can also beattached to the head holderfor imaging head films, wristfilms and panoramic x-rays.



The video monitor isattached that can be rotatedas the operator moves.

The images, text andnumerical data can bedisplayed, stored & modifiedusing either a light pen or astandard computer keyboard.



The digitizing handpiece is used torecord cephalometric data

The removable, sterilizable tip of thehandpiece is placed directly on thepatient to record a series of facialand intraoral landmarks. As eachlandmark is located, the handpiecebutton is depressed and the location isrecorded in three-dimensionalcoordinates (x,y,z). Each time the handpiece button is depressed, an audible sound is picked up by an array of four microphones on the beam . Thetime it takes the sound to reach eachof the microphones determines the

landmark location.



Any image appearing on the screencan be reproduced instantaneouslywith one of three "hard copy"output devices:

•

Sony video imager: makes 5 " x7 " color prints in 60 seconds• Polaroid freeze-frame cameraproduces Polaroid prints in 10

seconds;• Hewlett Packard Paintjetprinter makes 8 " x 10 " papercolor copies in 4 to 8 minutes.



RMO’S JIFFY ORTHODONTIC EVALUATION

»First to provide a computer aidedcephalometric diagnosis to the dentalprofession in the late 1960’s

»Marketed a software packagedescribed as JOE

»JOE generates tracings of lateral orfrontal cephalograms using Ricketts,Jarabak, Sassouni, Steiner &Grummons analyses



• JOE can also provide visual representationof normal for comparison to the patienttracings, generate collection ofcephalometric values listed in a logicalorder along the norms and amount ofdeviation from normal and put together a

list of orthodontic problem analyses.

PorDIOS (Purpose on Request Digitizer Input



( p q g pOutput System)

•

Is a cephalometric IBM compatible systemwhose development is aimed to provideorthodontists with a user friendly program.

• PorDios works with a digitizer in the standardway and also enables the use of a video orscanner as means of digitization of X-rays.

• Cephalometric analyses used areBjork,Burstone, Coben, Downs, Frontal,McNamara, Profile,Ricketts, Steiner andTweed

• Produces occlusograms from photocopies of



Produces occlusograms from photocopies ofdental casts

•

Has built in calculation functions for showingdiscrepancies between the actual mean andits deviation from the norms.

• Main system can automatically alter theorientation of a picture in order to havethe profile looking to the left or right side

of the screen.

• PorDios is multilingual .



•

During registration, points can bedeclared as missing or digitized at alater time.

• Drawings can be printed either on amatrix printer as a screen dump, ona laser printer, or on a colourplotter.



Dentofacial Planner• Is a computer aided software for diagnostic

and treatment planning in orthodontics andorthognathic surgery

• Works with an IBM compatible processor•

Analyses included are Steiner, McNamara,COGS, Downs, Grummons, Legan & Jarabak.• allows the user to do superimposition,

estimate facial growth, to simulate skeletaland soft tissue effects of orthopedicappliances and to simulate orthodontic toothmovements.

Computer Aided Space Analysis



Computer Aided Space Analysis• Chen Hsing Yen

• Bolton ratio

•

Tooth size relation of U & L arches

• Overjet and Overbite

• Posterior intercuspation

•

Arch lengthApplication of computers in orthodontics – Clinical / Graphic sem1/sb/09-04

Computerised Tooth Width Analysis



Computerised Tooth Width Analysis• Christopher T.C.Ho

& Terrence.J.Freer• Ho Freer Graphicalanalysis

• Digital callipers ormanual input forWindows

Five Screens

• Patient details• Mesiodistal tooth

width• Tooth width ratio• Tooth width excess• Graphic display


Advantages

Convenient, Consistent and Easy to operate

Ali ® T h l



Align® Technology

• Align® Technology, Inc. developed theInvisalign appliance for orthodontic toothmovement in the USA in 1998.

• It is an ‘invisible’ way to straighten teethinto a perfect occlusion using thin, clear,overlay sequential appliances.



Initial treatment planning with patients’ photographsand radiographs are sent toInvisalign® laboratory

Impressions are convertedinto positive plastermodels & checked forquality.



In the laboratory, models arefirst coated with protectiveshells, and encased in amixture of resin and ahardener.

After chemical setting, theybecome blocks of hardenedresin with plaster modelsinside. Each tray is placed in adestructive scanning machine



Graphic designers cut outeach tooth and save it as aseparate geometric unit

Once the teeth are separatedand re-assembled back intothe arches, the designerscreate a final set-up of whatthe patient’s teeth will look like when the treatment iscompleted



For each stereolithographicconstructed model (whichrepresents a treatmentstage), a clear Invisalign®aligner of 0.030 inchthickness, is created by heat

These aligners are trimmed, polished, cleaned and finallysent to the prescribingorthodontist.



• The patient is instructed

to wear each aligner forapproximately 1 –2weeks, and then to moveforward to the next

stage.• A series of evenly

divided 0.15 to 0.25mmmovements are broughtabout at each stage oftreatment.

Advantages :



Advantages :

Virtual treatment sequence presents anopportunity to the clinician & the patientfor evaluation of the proposed posttreatment occlusion on screen, before

treatment commences

Proposed treatment can be evaluated by

thorough examination of the entiresequence of tooth movement ,from manyvisual perspectives



Contraindications

patients with severe malocclusionsAll children – growing jaws and erupting

teeth make it too complicated for thecomputer to model

Magnetic Resonance Imaging



Magnetic Resonance Imaging• Magnetism is a dynamic

invisible phenomenonconsisting of discretefields of forces.

•

Magnetic fields arecaused by movingelectrical charges orrotating electric charges.

• Images generated fromprotons of the hydrogennuclei.



Equipment

The Gantry - houses the patientPatient is surrounded bymagnetic coils

Operating console - where theoperator controls thecomputer and scanningprocedure

Computer room network.



presence of specific magnetic properties

found within atomic nuclei containingprotons and neutrons.

Inherent property of rotating about theiraxis

Causes a small magnetic field to begenerated around the electrically charged

nuclei.



The dipoles exposed within a strong electricfield

Cause Orientation in response to the field

Signal is interpreted and image produced



Indications

Assessing diseases of the TMJCleft lip and palateTonsillitis and adenoiditis

Cysts and infectionsTumors



CONTRAINDICATIONS

Patients with cardiac pacemakers

Patients with cerebral metallicaneurysm clips. Slight movement ofthe clip could produce bleeding

Stainless steel and other metalsproduce artifacts, obliterate imagedetails of the facial area.



Shortcomings

Inability to identify ligament tears orperforations

Dynamics of tissue joint not possible

Cannot be used in patients sufferingfrom Claustrophobia.



Computed Tomography

Invented by Sir Godfrey Hounsfield whowas awarded a Nobel prize in 1979

CT is an image display of the anatomyof a thin slice of the body developedfrom multiple x- ray absorptionmeasurements made around the body’speriphery.



Parts of the Equipment:

Scanner ( m ovable x

ray table + gantry )

Computer system

A display console



Principle:An x-ray source and array of detectors

mounted within the gantry rotatearound the patient during each scan.

Detectors record the attenuation valuesof the beam emerging from thepatient

Information from each traverse is aProfile



The tube and detectorsare further angled andanother traverse ismade.

A series of Profiles arebuilt up.

The computer analysesthe data and an image isproduced.



Useful in determining

changes in bone density

Primary imaging method

when internal derangementor arthrosis is suspected

Has advantages whenplanning treatment oroperations on jaws and TMJdiseases and deformities.



Communication

Orthodontist’s Perspective

•

Searching Websites for Information• Medline, Pub med, NML… • Net Discussion•

Net Conferencing• Multispeciality Tele Surgery

Application of computers in orthodontics – Miscellaneous sem1/sb/09-04



Documents

Computers in Ortho - DR G.S FINAL YEAR