Tooth selection/ fellowships in orthodontics

ANTERIOR TOOTH ANTERIOR TOOTH SELECTION.SELECTION.

INDIAN DENTAL ACADEMY

Leader in continuing dental education www.indiandentalacademy.com

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Introduction.Introduction.• Anterior teeth selection and Anterior teeth selection and

arrangement is an area of arrangement is an area of prosthodontics where art dominates prosthodontics where art dominates science,where esthetics is the major science,where esthetics is the major concern,and where knowledge must concern,and where knowledge must be applied to create a pleasing be applied to create a pleasing appearance while simultaneously appearance while simultaneously maintaining oral function.maintaining oral function.


• The anterior teeth are primarily selected The anterior teeth are primarily selected to satisfy esthetic requirements.to satisfy esthetic requirements.

• Posterior teeth's are selected to satisfy Posterior teeth's are selected to satisfy masticatory functional requirements.masticatory functional requirements.

Technically, the anterior teeth are Technically, the anterior teeth are composed of 6 maxillary and 6 composed of 6 maxillary and 6 mandibular teeth's.mandibular teeth's.

Introduction.



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Introduction.Introduction.

Exceptions:Exceptions:oSometimes maxillary first Sometimes maxillary first

premolar is considered more for premolar is considered more for esthetics than for masticatory esthetics than for masticatory function.function.


• Patients expect 3 basic things form Patients expect 3 basic things form their complete dentures.their complete dentures.– Favorable appearance.Favorable appearance.– Comfort. Comfort. – Chewing ability.Chewing ability.


• There are four main considerations There are four main considerations in selecting the anterior teeth.in selecting the anterior teeth.

1.1. Tooth sizeTooth size2.2. Tooth moldTooth mold3.3. ColorColor4.4. Tooth materialTooth material


PRE-EXTRACTION GUIDES.PRE-EXTRACTION GUIDES.• PHOTOGRAPHS.PHOTOGRAPHS.• RAIDOGRAPHS.RAIDOGRAPHS.• DIAGNOSTIC CASTS.DIAGNOSTIC CASTS.• TEETHS OF RELATIVES.TEETHS OF RELATIVES.• EXTRACTED TEETH.EXTRACTED TEETH.


PhotographsPhotographs• More accurate than any other guide.More accurate than any other guide.• Shows the natural teeth or at least the incisal Shows the natural teeth or at least the incisal

edges.edges.• Provides information about width and outline form Provides information about width and outline form

of the teeth.of the teeth.• Known factors:Known factors:

– Width/length on photo.Width/length on photo. – interpupillary distance on photointerpupillary distance on photo– Interpupillary distance on patient Interpupillary distance on patient

• Unknown factor: length or width of teeth to be Unknown factor: length or width of teeth to be selected.selected.

• Recent photographs are of much value.Recent photographs are of much value.


New New dentures dentures made with made with the help of the help of old old photograpphotographh

•65 years: Poor esthetics with 15 year old dentures.

•Natural teeth at 20 years


• However, it is of value only when the However, it is of value only when the photograph is a full-face portrait of photograph is a full-face portrait of sufficient size.sufficient size.


DIAGNOSTIC CASTS.DIAGNOSTIC CASTS.

• Diagnostic casts of patients natural Diagnostic casts of patients natural or restored teeth. or restored teeth.

• Size and form of the anterior teeth Size and form of the anterior teeth can be determined.can be determined.


RADIOGRAPHS.RADIOGRAPHS.

• Can help in knowing size and form of Can help in knowing size and form of the lost teeth.the lost teeth.

• DisadvantagesDisadvantages::– Are always slightly enlarged.Are always slightly enlarged.– Distortion may be there.Distortion may be there.


TEETH OF RELATIVESTEETH OF RELATIVES..• Sons or daughters tooth size , color, Sons or daughters tooth size , color,

and arrangement can be effectively and arrangement can be effectively used in selecting and arranging used in selecting and arranging artificial teeth for their parents.artificial teeth for their parents.


EXTRACTED TEETH.EXTRACTED TEETH.

• Provides information as to the size Provides information as to the size and form.and form.

• Not to be used for selecting color.Not to be used for selecting color.


SELECTION OF SIZE.SELECTION OF SIZE.

• There are 2 dimensions to considerThere are 2 dimensions to consider

– The mesiodistal width. The mesiodistal width.

– The incisogingival length.The incisogingival length.


MEASUREMENT MEASUREMENT EDENTULOUS CASTS.EDENTULOUS CASTS.

• Inaccurate due to resorption of Inaccurate due to resorption of ridges.ridges.

• Occlusal rims to be constructed for Occlusal rims to be constructed for accurate measurements.accurate measurements.


• Gives the estimation of placement Gives the estimation of placement of apex of upper canines.of apex of upper canines.

• Extension of parallel lines from the Extension of parallel lines from the lateral surfaces of the alae of the lateral surfaces of the alae of the nose onto the labial surface of the nose onto the labial surface of the upper occlusion rim.upper occlusion rim.


Relationship between Relationship between intercanine distance and intercanine distance and nose widthnose width• It falls in the range It falls in the range

28-45mm28-45mm• Since anterior Since anterior

teeth are arranged teeth are arranged in an arc. the in an arc. the divider has to be divider has to be opened by 3-4mm opened by 3-4mm more than the more than the value of the nose value of the nose width.width. www.indiandentalacademy.comwww.indiandentalacademy.com

• Distal surfaces of the natural canines Distal surfaces of the natural canines is usually located near the corner of is usually located near the corner of the mouth.the mouth.


GENERAL GUIDE .GENERAL GUIDE .

• Upper anterior teeth whose overall Upper anterior teeth whose overall width is less than 48mm are width is less than 48mm are relatively small teeth. Those listed as relatively small teeth. Those listed as over 52mm are relatively large teeth.over 52mm are relatively large teeth.


Anthropometric Anthropometric measurements.measurements.Found from a study of 555 skulls.Found from a study of 555 skulls.• Greatest bi zygomatic width / 16 Greatest bi zygomatic width / 16

-gives approximation of -gives approximation of

the width of the upper central the width of the upper central incisors. incisors.

- also known as- also known as HOUSE HOUSE AND LOOP’S RULE.AND LOOP’S RULE.

• Greatest bi zygomatic width / 3.3 Greatest bi zygomatic width / 3.3 -Overall width of the upper -Overall width of the upper

six anterior teeth.six anterior teeth.www.indiandentalacademy.comwww.indiandentalacademy.com

• Lateral incisor are approximately 2 Lateral incisor are approximately 2 mm narrower and canine 1 mm mm narrower and canine 1 mm narrower than the central incisors.narrower than the central incisors.

• A facebow maybe used utilized to A facebow maybe used utilized to obtain these measurement.obtain these measurement.


Length of central incisorLength of central incisor

• Facial measurement methodFacial measurement method– Distance from the hair line to the Distance from the hair line to the

gnathion in millimeters with the face at gnathion in millimeters with the face at rest and divide this by 16.rest and divide this by 16.


• Amount of central incisor visible in Amount of central incisor visible in young-3 mm.young-3 mm.

• In old – 11/2 mm.In old – 11/2 mm.


Using trubute tooth Using trubute tooth indicator.indicator.


UNIVERSAL DENTAL UNIVERSAL DENTAL COMPANY MOLD COMPANY MOLD SELECTORSELECTOR


INCISAL PAPILLA – INCISAL PAPILLA – CUSPID CUSPID EMINENCE/BUCCAL EMINENCE/BUCCAL FRENUM.FRENUM.• A line is placed on the cast at the A line is placed on the cast at the

distal termination of the cuspid distal termination of the cuspid eminence.eminence.

• When eminence are not discernible a When eminence are not discernible a line is placed slightly anterior to the line is placed slightly anterior to the attachment of buccal frenum.attachment of buccal frenum.


MAXILLO-MANDIBULAR MAXILLO-MANDIBULAR RELATIONS.RELATIONS.• In protruded mandible the anterior In protruded mandible the anterior

teeth's are frequently larger than normal.teeth's are frequently larger than normal.• If mandibles are retruded, the mandibular If mandibles are retruded, the mandibular

anterior teeth are frequently smaller.anterior teeth are frequently smaller.• In protrusion the face is usually longer In protrusion the face is usually longer

and longer faces usually require longer and longer faces usually require longer teeth's.teeth's.


VERTICAL DISTANCE VERTICAL DISTANCE BETWEEN THE RIDGES.BETWEEN THE RIDGES.

• The length of teeth is determined by The length of teeth is determined by the space between the ridges.the space between the ridges.

• When space is available it is When space is available it is advisable to use long teeth.advisable to use long teeth.


Lips.Lips.• Help in determined the length of the Help in determined the length of the

teeth.teeth.• The maxillary incisal edge extends The maxillary incisal edge extends

inferior to or slightly below the lip inferior to or slightly below the lip margin.margin.

• ..


• When teeth are in occlusion and lips When teeth are in occlusion and lips are together, the labial incisal third are together, the labial incisal third of the maxillary anterior teeth of the maxillary anterior teeth supports the superior border of the supports the superior border of the lower lip.lower lip.

• In speech the incisal edges of the In speech the incisal edges of the maxillary anterior teeth contact the maxillary anterior teeth contact the lower lip at the junction of the moist lower lip at the junction of the moist and dry surfaces of the vermilion and dry surfaces of the vermilion border. As in pronouncing fifty fiveborder. As in pronouncing fifty five


Inner canthal distanceInner canthal distance• Inner canthal distance Inner canthal distance

can be used to can be used to estimate the estimate the mesiodistal width of a mesiodistal width of a maxillary central maxillary central incisor for an incisor for an edentulous patient.edentulous patient.


• Size of the teeth should be in proportion Size of the teeth should be in proportion to the size of the face and head.to the size of the face and head.

• Larger persons have larger teethLarger persons have larger teeth• But a large person may have small teeth But a large person may have small teeth

with spaces between the teeth.with spaces between the teeth.• Or a small person may have large Or a small person may have large

irregular aligned teeth.irregular aligned teeth.



• Woman have smaller teeth than Woman have smaller teeth than men.men.

• Lateral incisor should look more Lateral incisor should look more delicate in woman.delicate in woman.

• Size difference between central and Size difference between central and lateral incisors should be more lateral incisors should be more distinct in woman. distinct in woman.


Selection Of Form(shape Selection Of Form(shape or mold).or mold).• Form of artificial anterior teeth should Form of artificial anterior teeth should

harmonize with the shape of the patients harmonize with the shape of the patients face.face.

• Outline form is considered from a front Outline form is considered from a front view of the patient.view of the patient.

• The face from is identified by connecting The face from is identified by connecting the following points on the lateral aspect of the following points on the lateral aspect of the face;the face;– the forehead,the forehead,– the zygomatic archthe zygomatic arch– Angle of the mandible.Angle of the mandible.


4 basic Outlines of faces 4 basic Outlines of faces • This was firs considered important by williams and This was firs considered important by williams and

house and loop house and loop (Leon Williams classification)(Leon Williams classification)– SquareSquare

• Square taperingSquare tapering– Tapering Tapering – ovoid ovoid


• The shape of The shape of the maxillary the maxillary central incisor central incisor should resemble should resemble the shape of the the shape of the face if it were face if it were inverted.inverted.

• This method This method selection is also selection is also called as called as GEOMETRIC GEOMETRIC THEORY.THEORY.



RELATION BETWEEN RELATION BETWEEN TOOTH SHAPE AND ARCH TOOTH SHAPE AND ARCH SHAPESHAPE


• Check three points: the forehead,the Check three points: the forehead,the base of the nose,and the point of the base of the nose,and the point of the chin.if these three points are in line ,the chin.if these three points are in line ,the profile is straight.profile is straight.

• 3 types of profiles are 3 types of profiles are • ConvexConvex• straight straight • concaveconcave


SELECTION OF SHADE.SELECTION OF SHADE.

•COLOR HAS 4 QUALITIES.COLOR HAS 4 QUALITIES.


HUEHUE

• The hue of the teeth must be in The hue of the teeth must be in harmony with the color(Hue) of the harmony with the color(Hue) of the the patients face.the patients face.

• In teeth guides yellow is the In teeth guides yellow is the dominant hue.dominant hue.


• Saturation (chroma)Saturation (chroma)– It is the amount of color per unit area.It is the amount of color per unit area.– Some teeth appear more yellowSome teeth appear more yellow

• Brilliance (value) it is the lightness Brilliance (value) it is the lightness or darkness of an object. or darkness of an object. – The relative amount of white or black The relative amount of white or black

in the teeth determines their in the teeth determines their lightness or darkness.lightness or darkness.


THE COLOR OF THE COLOR OF HAIRHAIR


Color of eyes. Color of eyes. • Color of eyes has been suggested as Color of eyes has been suggested as

guide to select the color of teeth.guide to select the color of teeth.

• Not a sound method since color of Not a sound method since color of Iris is so small compared to total Iris is so small compared to total face and the eyes are not close to face and the eyes are not close to the teeth.the teeth.


Color of face.Color of face.

• It should be the basic guide to select It should be the basic guide to select tooth color.tooth color.


Age and colorAge and color• Color of natural teeth progressively Color of natural teeth progressively

darkens with age.darkens with age.• Pulp chamber becomes smaller with age Pulp chamber becomes smaller with age

due to deposition of secondary dentindue to deposition of secondary dentin• This makes the tooth more opaque and This makes the tooth more opaque and

reduces the effect of pulp color.reduces the effect of pulp color.• As wear occurs due to abrasive forces the As wear occurs due to abrasive forces the

tooth becomes smoother and more tooth becomes smoother and more reflective.reflective.


Jaw relation and color.Jaw relation and color.• Class 1 same selected for both the Class 1 same selected for both the

arches.arches.• Class 3 : prognathic patient slightly Class 3 : prognathic patient slightly

darker teeth for the lower arch than the darker teeth for the lower arch than the upper as lighter teeth will stand out.upper as lighter teeth will stand out.

• Class 2 : lighter teeth than the upper Class 2 : lighter teeth than the upper to give the illusion that the teeth are to give the illusion that the teeth are more anterior than they really are.more anterior than they really are.


Selecting the color.Selecting the color.• It should be done in 3 positions It should be done in 3 positions • Outside the mouth along the side of Outside the mouth along the side of

the nose.the nose.• It will establish the basic It will establish the basic

hue,brilliance,and saturation.hue,brilliance,and saturation.


Selection of tooth material.Selection of tooth material.• Conventional acrylic resin Conventional acrylic resin • Interpenetrating polymner Interpenetrating polymner

network(IPN) acrylic resinnetwork(IPN) acrylic resin• Composite resin teethComposite resin teeth• Porcelain.Porcelain.


Indications for resin teeth.Indications for resin teeth.• Recent extractions Recent extractions • Immediate denturesImmediate dentures• Limited interocclusal distance.Limited interocclusal distance.• If current denture producing clicking If current denture producing clicking

sound.sound.


Composite resin teethComposite resin teeth• It consists of an organic filler and It consists of an organic filler and

liquid matrix based on a modified liquid matrix based on a modified Bowen resin.Bowen resin.

• Liquid matrix and the organic filler Liquid matrix and the organic filler contain approximately 20% Pyrolytic contain approximately 20% Pyrolytic silicium dioxide,which is used as a silicium dioxide,which is used as a thickening and strengthening agent.thickening and strengthening agent.


Porcelain teeth.Porcelain teeth.• Highest wear resistance.Highest wear resistance.• Good stain resistance.Good stain resistance.• Disadv: clicking sound in Disadv: clicking sound in

nervous patients and with nervous patients and with those having neuromuscular those having neuromuscular coordination problems.coordination problems.

• More prone for chipping and More prone for chipping and fracture.fracture.

• Cannot be given when Cannot be given when interarch space is less.interarch space is less.


Dentogenic conceptDentogenic concept• By frush and fisher on 1957By frush and fisher on 1957• Also called SPA theoryAlso called SPA theory• SexSex

– male male – FemaleFemale

• PersonlityPersonlity– Vigrous delicateVigrous delicate

• Age Age – YoungYoung– Middle ageMiddle age– Old.Old.



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Tooth selection/ fellowships in orthodontics