﴿لَيلَةُ القَدرِ خَيرٌ مِن أَلفِ شَهرٍ﴾.
اللهم لا تحرمنا نورها وبركتها وأجرها وعتقها
اللهم لا تحرمنا نورها وبركتها وأجرها وعتقها
و هذا جزء من ملخص محاظرة Try in للنقاط المهمة
Any occlusal prematurities should be relieved using green stone bur.
Objectives: is to obtain at least one mm wide margin that is closely adapted to the tooth surface at the area of finish line to prevent microleakage.
1. Sub gingival margin can be finished on the die using burnisher, no intra oral finishing is desirable because of the risk of damaging the tooth and the periodontal tissue.
2. Supra gingival margin can be finished directly on the tooth, margin adaptation can be improved by using burnisher or dull bur.
Dental cement doesn't contribute to the retention of the restoration. It is used only to fill the microspaces between the tooth structure and the restoration when it sets.
Zinc phosphate cement
It is the traditional luting agent that have proven itself after years of work, it has compressive strength of 14000-16000 PSI, with low PH at the time of cementing (about 3.5)
Zinc silicophosphate cement
Has compressive strength of 22000 PSI but it has highly acidic PH which may affect the health of the pulp (irritant).
Poly-carboxylate cement
Adhere to enamel, dentine and stainless steel but not to gold alloy, the setting PH is (4.8) but because of the large size of poly-acrylic acid molecule, it has less effect on the pulp, high bond strength to enamel (1300 PSI) but its binding to dentine is considerably less 480 PSI.
Traditionally used for vital or sensitive teeth,
Glass ionomer cement
has compressive strength of 18600 PSI and it bonds to enamel and dentine (to enamel more), it releases fluoride after setting which is indication of an ability to inhibit secondary caries.
Used empirically for conventional crowns where patient has had a previously high caries rate.
Zinc phosphate cement is used
1. When maximum retention is required. 2.
The pulp of the tooth is of no concern.
3. Also, we use it on endodontically treated teeth or teeth with heavy amalgam filling.
When the depth of the preparation raise some concern about the vitality of pulp.
Seat the casting crown on the tooth with pressure and have the patient to apply force to the occlusal surface of the casting by biting on wooden stick or cotton roll for 3-4 minutes (to ensure complete seating).
Isolate the prepared tooth and acid etch the prepared tooth surface for 30 seconds with
37% phosphoric acid gel, rinse and dry gently with air syringe.
Apply universal bonding agent on the etched surfaces for 10 seconds, dry gently and cure
for 15 seconds.
Etch the internal surface of the restoration with 9.5% hydrofluoric acid for 30 seconds, rinse
and dry gently, apply special zircon bonding agent for 15 seconds, dry and cure for 20
seconds.
Any occlusal prematurities should be relieved using green stone bur.
Objectives: is to obtain at least one mm wide margin that is closely adapted to the tooth surface at the area of finish line to prevent microleakage.
1. Sub gingival margin can be finished on the die using burnisher, no intra oral finishing is desirable because of the risk of damaging the tooth and the periodontal tissue.
2. Supra gingival margin can be finished directly on the tooth, margin adaptation can be improved by using burnisher or dull bur.
Dental cement doesn't contribute to the retention of the restoration. It is used only to fill the microspaces between the tooth structure and the restoration when it sets.
Zinc phosphate cement
It is the traditional luting agent that have proven itself after years of work, it has compressive strength of 14000-16000 PSI, with low PH at the time of cementing (about 3.5)
Zinc silicophosphate cement
Has compressive strength of 22000 PSI but it has highly acidic PH which may affect the health of the pulp (irritant).
Poly-carboxylate cement
Adhere to enamel, dentine and stainless steel but not to gold alloy, the setting PH is (4.8) but because of the large size of poly-acrylic acid molecule, it has less effect on the pulp, high bond strength to enamel (1300 PSI) but its binding to dentine is considerably less 480 PSI.
Traditionally used for vital or sensitive teeth,
Glass ionomer cement
has compressive strength of 18600 PSI and it bonds to enamel and dentine (to enamel more), it releases fluoride after setting which is indication of an ability to inhibit secondary caries.
Used empirically for conventional crowns where patient has had a previously high caries rate.
Zinc phosphate cement is used
1. When maximum retention is required. 2.
The pulp of the tooth is of no concern.
3. Also, we use it on endodontically treated teeth or teeth with heavy amalgam filling.
When the depth of the preparation raise some concern about the vitality of pulp.
Seat the casting crown on the tooth with pressure and have the patient to apply force to the occlusal surface of the casting by biting on wooden stick or cotton roll for 3-4 minutes (to ensure complete seating).
Isolate the prepared tooth and acid etch the prepared tooth surface for 30 seconds with
37% phosphoric acid gel, rinse and dry gently with air syringe.
Apply universal bonding agent on the etched surfaces for 10 seconds, dry gently and cure
for 15 seconds.
Etch the internal surface of the restoration with 9.5% hydrofluoric acid for 30 seconds, rinse
and dry gently, apply special zircon bonding agent for 15 seconds, dry and cure for 20
seconds.
محاظرة الDiagnosis عبارة عن شرح فقط درخ ما بها شغلات معينة تركز عليها كذلك معلومات عامة و آخر لكجر للآن ما قاري ما سويت ملخص عنه 🗿