Crown Lec 2

‫بسم ال الرحمن الرحيم‬ ‫ بس بسيطه‬, ‫ الدكتور موسى مراشده رائع مع انو عجب علي بعيادة البروستو‬,‫اول شي المحاضرة بتجنن من الخر‬  ‫لبد من ذلك كونا طلب التكنو‬ ‫التسجيل كان واضح الحمدل بس شكرا الك اخ اياس ! التسجيل كان جنبوا و ما قصرت وال‬ ‫ييجي‬

no need ‫ و قال اللي ما معو قلم‬quiz ‫دخل الدكتور و صار يبهدل كيف ما معنا اقلم و عنا‬ ! ‫ فسأل اياس طب دكتور و اللي ما معو محاي و براي شو يعمل؟ هاهاهاها مش هيك خفة الدم‬, ‫المرة الجاي‬

‫و صوت الخ اياس و هو بغش مش طالع ال شوي و ياريتك بتغش صح ! يعني‬

quiz ‫بعدين بتذكروا اعطانا‬

):.....‫انا بقلك جوابك غلط‬ ‫ما تزعل منا بس حبينا نغير جوي بالبداية عشان هل بدنا نبلش المحاضرة بدها تركيز‬

Treatment planning of fixed prosthodontics: Last time we talked about crown and bridge and we said this fixed prosthodontic involves single tooth restoration and replacement of missing tooth, so your treatment plane should be aided in this direction other you will go for single teeth restoration or you go for replacement missing tooth . Treatment planning will start with single tooth, right?ok single tooth restoration ( simple filling , inlay , onlay , crown),veneers ok You decide to make restoration of your tooth, type of restoration depends on the type of restoration material and design , and these 2 things will be controlled by the amount of tooth structure left after damage. Imagine you have a tooth with class 2, if it was simple class 2, you will think of plastic restoration ( amalgam, composite, cement) if more damaged u will go for inlay, onlay, then crowns. So the amount of damage will determine the type of your restoration, now the type of ur

restoration will depend on the material u will use and the design u will choose ! Selection of material and design : This will depends on : 1- general factor :remember all the speak about single tooth restoration ok, and these are age ,cost ,like 20years lady with class 2 on upper right 4 , and she is very concern about esthetic so you think about composite, if 75 years old man you will think about amalgam coz esthetic is 2nd priority to the function. Some restoration needs more oral hygiene control than others, like if u go for cast restoration you need more oral hygiene control than amalgam restoration, so if the patient is motivated enough, I will go for more complex restoration if not I will go for more simple one . 2- local factors: 1. destruction of tooth structure, if u have badly broken lower left 6 with class 2 or DO, MO, when u prepare amalgam cavity with outline form, convenience form, retention form, true? So, how you get retention in class 2? From undercuts, u create undercuts in box in dovetail area and these undercut can be created in one scenario if there is enough tooth structure, if not you cant place amalgam so u think with something else . Other thing if u have simple class 2, direct class 2, u don’t open the marginal ridge in such a case it is direct access so place composite coz there is no direct load, so amount of destruction guide u to the type of material u will be using .

(Direct Load is the load from biting) 2. esthetic 3. plaque control : much easier be controlled in simple restoration than complex one 4. retention , if u don’t have enough retentive feature for the cavity then amalgam cant be used Is that clear ! In single tooth restoration we will talk about intra coronal restoration which are 1. Simple restoration – amalgam, composite, cement2. inlay 3. onlay then extra coronal restoration intra coronal restoration is very essential coz u have to understand how to judge the restoration type u want . intra coronal restoration is the restoration which r retained within confines of the tooth, and when I spoke about this I spoke about simple restoration, fixed prosthodontic when are inlays and onlay, now if u decide to place intra coronal restoration, there are 2 factors u think about 1- sufficient remaining tooth structure, 2- that will provide you by retention, support, integrity . if u want to place inlay u need sufficient tooth structure so that when u place it the tooth in function wont split lower 1st premolars are very narrow tooth bucco-lingual and if u have MOD on it, and u want to create inlay u will cross from mesial to occlusal to distal and the occlusal part is very narrow, so if u create ur inlay, there will be very narrow structure, bucculy and lingualy to ur restoration, this narrow walls could fracture for this reason, such kind of tooth is unlikely for MOD inlay, I

might think MOD inlay if I have molar, coz B-L width quit big, then if sufficient tooth structure it will lead me what to do? What kind of restoration I have to design, this tooth structure will provide me retention, support, integrity and for the last time if you have huge class 2 amalgam, and u cant create contour so u cant use amalgam coz matrix band will squeeze it and u cant reform the morphology in such case inlay, onlay not amalgam! so tooth want be suitable for intra coronal restoration if it cant provide u retention, support, integrity . ‫ اللي يستحمل الحشوة و ما‬tooth structure ‫باختصار اذا كان السن كتير كتير مسوس و مو باقي عن‬ .‫ رح ادور على شيء يغطيه كله‬cracks or root fracture ‫ينكسر او بصير فيو‬ Intra coronal restoration : 1- plastic restoration 2- cement retained restoration and if they are cement retained restoration they are fixed prosthodontics. and they r: 1- metal inlay its class 2, MOD ok onlay is like inlay but with occlusal coverage to protect cusps and for inlay there should be sufficient tooth structure and in case lower premolars ,I can do MO, DO, inlay not MOD inlay coz there is no tooth structure , I can do MOD onlay on lower premolar, coz it will protect lingual+ buccal walls and if it can not, we will go for crowns 2. ceramic inlay 3. MOD onlay, the message u should pick it from this lecture is the onlay is preferred for metals, because u need

tooth preparation which is usually achievable, but MOD ceramic onlay you need to cut too much occlusaly The thickness of the cut 2-2.5 mm for ceramic onlay and this is too much destructive . MOD onlay with metal needs 1-1.5 mm cuts so more conservative , In other words I can use MOD onlay for molars because they are away from the patient smile, and here the tricks in Qs come. Can u use MOD onlay on posterior molar? yes Is MOD onlay indicated for upper premolar? no Neither MOD onlay with metal coz its unaesthetic, nor MOD ceramic coz its destructive so…..crowns Ceramic onlay are too destructive when prepared so not recommended. Extra coronal restoration : The one that covers buccal, lingual, mesial, or distal, here there is no sufficient tooth structure, so the underneath support, retention, tooth structure is weak enough General indications are: 1. badly broken, heavily restored teeth 2. primary truma 3. tooth wear 4. hypo plastic condition 5. altered shape 6. altered occlusion 7. appearance 8. non vital tooth

9. combined and others slide 7 pic on upper left is for heavily restored molar with cracked root pic on upper right for rooted anterior teeth (RCT) with post crowns pics on lower are for advanced tooth wear where u can see enamel rim and erosion. Crowns : Crowns there are anterior crowns and posterior crowns Anterior one: Could be classified according to the material u will use, fabricate with, or by design According to material : 1- metal ceramic crowns MCC or called PFM porcalin fused metal 2- all ceramic crowns 3- others according to design : either 1. full crown or 2. partial crown were one of the surfaces is not covered dana asked : what is the difference btw partial crown and onlay? Dr. answered partial crown is extra coronal restoration, and the onlay is intracoronal restoration Ameen asked: do we consider veneer as partial crowns? No

Nisreen asked: do veneers need sufficient tooth structure? yes Ya jama3a veneers are ceramic restoration on the labial face of upper anteriors mainly for esthetic reason ok The partial crown is to strength the tooth ok Posterior crowns: According to material: 1- full mouth crowns 2- MCC 3- All ceramic crown 4- Other And the first one is on the top of use According to design : 1- full 2- partial

ok

The other extra coronal restoration is ceramic laminate veneers as other option for crown and they are: 1- Conservative alternative to crowns 2- Produce very cosmetic effect on anterior teeth 3- Are mainly stained or malformed We end the first which was for about single tooth restoration Now we will talk about the other part which is about replacement of missing teeth Now why do we replace missing teeth? 1- esthetics 2- function as they cant eat

Occlusion as lower 5 extraced so the 4 will drift distally and 6, 7 drift mesially and the upper will over erupt so the occlusion is dynamic and I need to prevent the occlusion deterioration as in pic in slide13 page 3 ok 4- Combination do we always need to replace missing teeth? No if we have stable occlusion, and the patient doesn’t complain from esthetic and function no need to replace ok there is concept called short dental arch SDA, this concept when patient come and he is missing molars (so from left 5 to right 5 )and he has 10 occlusion pairs (upper+lower)so 10 stopper or centric pairs, he doesn’t complain from esthetic and he has stable occlusion so don’t rush to replace them with kindy class1 bilateral free end saddle ok 3-

now if we decide to replace, what are the types of prostheses? 1- RPD is the only one removable 2- Conventional fixed partial denture\bridge 3- Resin-bonded FPD 4- Implant-supported FPD What are the factors for selection of the prostheses? 1-general factor: age, health, occupation, cost, gender those will dictate u to choose fixed or removable PD ok 2- Local factors: which will satisfactory the oral hygiene Poor oral hygiene is contra indicate for RPD OK then the dr mention from slide what are the local factor (slide #17) and said that there is table in the book should be memorized by heart ok

Now conventional FPD from now conventional related to the type of cement will be loot (as I heard) ur restoration with ok, and read the local factor from slide 18 Resin – bonded FPD : Are Resin based cement Usually for single incisor for lower central incisors and usually the abutments are defect free ok, pic on slide 20 page 4 is for resin bonded bridge,2 wings cemented on the canine and central ( coz her we have missing 2) , and we use the cement coz surface area of looting is small only palatal surfaces, then if u use conventional it wont be strong to retain it. Bridges: According to the design they could be : 1- fixed-fixed, the abutments are parallel to have single line of draw 2- fixed-movable, here the pontic connected to major retainer (fixed)by rigid connector and the other side is connected by movable connecter to minor retainer, which needs no parallel ok, so its more conservative in preparation ok 3- cantilever bridge 4- hybrid\compound direct canti lever when the pontic connected from oneside has one retainer ,so the pontic and the retainer next to gether, next to the saddle, and if it was far away its called spring canti lever and it has tooth + mucosa support like

1st pic on slide 24, and the lower is for direct canti lever where central incisor carried on the lateral, if we have diastema and u want to close it so use spring cantilever not direct one but the only disadvantage for it if the opposing tooth for the prmolalr is missed which lead to supra eruption and u want to put the retainer on this premolar it will take the central incisor with it during supra eruption coz they are connected together ok retainer:: 1- full covarge crown which is the best 2- 3\4 crown is not recommended 3- post retained crown 4- onlays 5- inlays this pic on slide 26 is for implants joined by bridge ok then the dr read the slides ok, and he said these r guide lines not for Qs in the exam ok the most important to know is prosto is the last treatment plane or option ok…… thanks God finish

Dina sameir kamal

Special thanks for eman el ras who gave me her lap top to print it in the sakn ! Meso o madoo7 as always Gada, amane 3fane, dalia, sukainah, lina, faroooooooooooo7 , shaheeed, fatoooom, ferma, nissren, dana, arwa, dema a7la jeran lamia, du3a2, maimaneh, aseel, ronze, sheren esra2 3bd el gane, jameleh,razan the best best wishes for NOOR 3BD EL HANE for her engagement     32bal el kol yarab 