crown-and-bridges- lec 1 - indications for c & b

8/13/2019 Crown-And-Bridges- Lec 1 - Indications for C & B

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script number (1) , Title : Indications for crown and bridges , Date 28 / 1 / 2014

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Genaral Indications :

-Firstly , you have to suppose that your friend , sister , brother etc has a

missing upper central , or discolored or fractured . The first problem with thispatient is esthetic .

-Also if he has missing 6 what is the problem ? function ( he wants to eat ,

simply ) .

-Sometime maybe we have problem with Phonetics

- If you extract lower 6 then upper 7 will over-erupt and 5 , 6 will tilt , so

Occlusion .

From Caries to crown

we start with caries , end with a crown ( not every case but it is general

speaking ) , if we have a caries we remove the caries then if it is small cavity so

we need a filling , But if it is large cavity and no enough tooth structure then we

need a [ cast restoration ]

so our choices are :

if there is enough tooth structure Filling

if there is no enoughtooth structure inlay onlay overlay

S C R I P T N U M B E R ( 1 )

INDICATIONS AND CONTRAINDICATIONS FOR

CROWN AND BRIDGES PT TITLE

General Indications : esthetic / Function / Occlusion / Phonetics

First CROWNS


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Inlay (mesial or distal cavity )

Onlay ( MOD cavity )

Overlay ( MOD cavity including the whole cusp )

CROWN (the tooth is entirely destructed )

If I have a destroyed tooth so I have to do preparation to remove enough

tooth structure to accommodate new crown

But if I have missing tooth for example 6 , so I have to prepare 5 and 7 to put

the bridge , SO :

BRIDGEis a prosthesis to restore missing tooth ,

by preparing the 2 adjacent teeth .

CROWN it is a prosthesis to restore entirely destructive tooth

, by preparing the tooth itself to receive this prosthesis

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Other Indication :

1) Badly broken-down teeth

2) Heavy filled tooth : I do cavity and do filling but the filling will not bestrong enough so I want to protect my filling.

3) Fractured tooth : ( bcz if I put a filling it will not withstand the bitingforce).

4) Tooth wear : ( abrasion , attrition , abfraction , erosion etc)if the pt has attrition and he will lose the vertical dimension .

5) Hypoplastic condition : ( like amelogensis imperfecta dentinogensisimperfecta ) this will affect texture and structure of the tooth so will

affect esthetic .

6)Alter shape or size or inclination of the teethExample of changing shape pig lateralAlso if I have slightly inclined tooth and I want to modify it I might needcrown.

7) Alter the occlusionTo correct the occlusion and vertical dimension I might need crown .

8)As a part of other restoration :When we have missing tooth the crown will be part ofthe bridge , when the crown is a part of bridge itsname will be ( retainer )we will explain it later


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OkI have to think about something other than crown .. bcz crown is verydestructive procedure , you have to remove from tooth structure , I have

to reduce from tooth size so Ill be closer to the pulp .. so I will dangerthe pulp so Im doing something will cause a problem

So what is the alternatives ?

1)bleachingIf your problem with esthetic you have to think about itIt is conservative, you dont remove tooth structure but I dont like bleaching bcz it is

recurrent , it is good for short time , ur enamel and dentine will absorb coffee , tea ,

argela etc so ur original teeth color will return )

2)Resin composite or restoration:If I have discolored upper central I can put composite facing( very thin composite ) , it is cheaper for the patient , quicker time inone visit

3)Inlay and onlay ( gold , ceramics .. etc .)It is more conservative bcz u cover the tooth structure without doing

the full preparation , only on the occlusal surface , on some cusps or

part of them , but not the whole tooth structure .

4)Porcelian laminate VENEER .VENEER very thin porcelian, exactly like the nail of finger. You have to

remove very thin layer of enamel, you cement it the pt mouth. It is

very aesthetic and conservative .. It is the Best solution in Dentistry.

For example if you have flourosis with

some pits like this patient , you cant

do preperation for this tooth ! so the

best solution is to do veneers

See here how the veneer

is very thin just like ur

finger nail


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5)Esthetic filling : composite / GIC .. etc6)Implant :

If you have missing tooth we can do implantWe dont touch the adjacent teeth , we go inside

the bone and soft tissue , we drill and put titaniumimplant and leave it for 4-6 months ( according if it is upper orlower ) until we reach the osteo-integration ( in Arabic ) and thistitanium become as your root .

TYPES OF CROWNS1) Full Ceramic crown2) Full Metal crown3) Ceramometal crown

Which [ filling , inlay or onlay ] should I choose ?

Ok , now , I will not spend much time in this topic bcz you take it in

conservative ..

If you have lower 6 with large class 5 , what filling I have to use ? (amalgam,composite , GIC .. ??)There are many factors affect the choice like moisture control ( sensitivity ) /enough tooth structure / Aesthetic / Vision zone/ occlusion / strengthSo I prefer amalgam for lower 6 or GIC , ok u can use composite but if it is subgingival it is difficult to etch and difficult to have a good moisture control.


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Very Important NOTE :It isnotREMOVABLE , it is MOVABLE ..if u write it in exam removable you will get ZEROMovablemeans that it is moving .Removablemeans you can remove it away .You have to differentiate !!

So this movement of the fixed-movable bridge >> will reduce the stressfrom the masticatory forces that applied on the bridge and on toothstructure .

3) Resin bonded bridgewhat is the difference between normal bridges and resin

bonded bridge ?

Resin bonded is more conservative , I remove from the palatal surface about

0.5 mm , while the other bridges I need about 2 mm , also it will needtemporary filling , needs anesthesia , but the resin bonded needs nothing ,

Now the survival rate for the other bridges is higher ( each of them has anadvantages and disadvantages ) Any way .!

Advantages

1)appearance2)occlusal stability3)The Ability to Eat4) speak and phonetics

5)periodontal splinting6)feeling of confidence7)orthodontic retention8)To restore the vertical dimension


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Disadvantages:

1) Destruction to the toothIt may lead to pulp exposure

2) Artificial margins .When we put the crown we will have artificial margins which may

accumulate the plaque leads to caries.

3) Failure .4) Effect on the periodontum:

(if you remember the fatal mistake in amalgam is OVER HANG not carving the

reason in almost cases is the student dont put the wedge ))

5) cost and discomfort:Let the patient to choose unless he asked your advice .

The Choice Between The Removable And Fixed Prosthesis

1) Patient attitudeSome pt doesnt care of appearance other pt they care

2) Factor age and gender:some thinks said that female who look for something fixed and nice

On other hand , the young is not like the old man .

3) Confidence :when u have a nice and healthy teeth , you will be self-confidant

4) Occupation :like the interviewer on TV , it is not acceptable if he has a broken tooth for

example !


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5) General healthFor example you have a patient with cancer , you cant bring him for 3 visits

or 4 visits . So the easier is to do RPD ( this is an example ).

6) oral hygiene7) Appearance8) Local consideration

This mean that you have to examine each tooth alone and then to decide

The first Example: If I have missing lateral , and I have upper central and

upper canine , and the canine and central are mobile , shall I do bridge for

him ? No because bridge will apply more stress on the abutment , andalready I have a mobile tooth , So Best choice is partial denture . But the

problem is that the PD is not as kind on soft tissue than the bridge , and it

cause periodontal disease more than bridge , bzc P.denture covers more soft

tissue while bridge will cover less area .

Another example, if you want to replace a tooth but the adjacent tooth is

periodontaly involved , you cant do a bridge , you have to do P.D

OR you can extract it and it will be as a part of the bridge .

And Finally I hope this script was easy and interestingand sorry for any mistake ..Eman Nazzal

! . :...

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crown-and-bridges- lec 1 - indications for c & b

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