Dental Asia May/June 2018

More documents

Recommendations

Info

Behind the Scenes With a light curing resin, the rims’ produced the basis for an aesthetic set-up. Since the treatment plan involved the construction of a milled bar and a superstructure, in order to reduce the encumbrance of the prosthesis, a set of preformed composite veneers were used. With the models positioned on the articulator, the veneers were placed on the resin basis, following the aesthetic indications of the transparent replica, using a hard wax (Fig. 5). In agreement with the p a t i e n t , t h e f o l l o w i n g s e t o f t e e t h : t h e I 4 7 s e t f o r t h e a n t e r i o r t e e t h a n d t h e L3 form for the posterior teeth was selected. The purpose of this rst assembly is to obtain an aesthetic prototype to be delivered to the clinician. Fig. 3: Master model Fig. 4: Master model with articial gingiva and analogues in position Aesthetic try-in The patient was given the opportunity to evaluate the aesthetic result of the restoration prior to the finalisation. The clinician with the set-up inside the patient’s mouth evaluated the aesthetics, phonetics, overall dimensions of the buccal anges and the resulting support for the upper lip and colour of the dental elements. The occlusal relationships were also controlled, together with the protrusive and lateral movements (Fig. 6). The necessary adjustments were made directly to the chair, being the aesthetic facets mounted on wax. With the patient’s agreement, the prototype was delivered to the laboratory after the disinfection protocol. Fig. 5: Aesthetic prototype Fig. 6: Try-in of the aesthetic prototype Fig. 7: Reference mask on the articulator Realisation of the bar In order to preserve the changes made by the clinician, a silicone key was created (Universal, Transformer) using an articulator (Fig. 7). Subsequently, the master model and the aesthetic prototype were positioned inside a ask, using the plexiglass cover, suitable for the light curing of the composite. Two wax pins for spruing were connected to the prototype to create the injection channels, then once the flask was closed it is injected with a t r a n s p a r e n t s i l i c o n e 2 2 s h o r e ( F i g . 8 ) . After curing, the prototype and the master model were removed from the ask and digitised through a laboratory scanner and then the les were loaded to a modelling software, exocad (Fig. 9). The design of the primary bar has been relative according to the teeth set- up in order to put the attachments perpendicular to the occlusal plane. The bar surface facing the gingiva was drawn convex to minimise the accumulation of plaque/food and to facilitate the manoeuvres of hygiene. Using the CAD/CAM technique, the bar has been obtained by milling from a solid titanium alloy block (Fig. 10-11). Four attachments, with the respective housings, were put on the bar. The attachment chosen (OT Equator) has a reduced vertical dimension compared to the spherical attachments, which allows saving space with an even stronger retention. Such attachments were screwed into the thread inside the bar created directly by the milling centre - this avoided the use of adhesive materials or to perform a weld (Fig. 12). The threaded attachments allow for quick and easy replacement without removing the bar. The bar with the attachments screwed was delivered to the clinician. Verification of the liabilities of the bar The clinician proceeded to screw the bar on the abutments, verifying its passive seating (Fig. 13). The distance between the gingiva and the bar, plays a crucial role in daily hygiene, was checked, and a test 60 DENTAL ASIA MAY / JUNE <strong>2018</strong>
Behind the Scenes was performed to verify that the patient was able to use floss and brushes. The compressive points on the gingiva were reduced. The bar was returned to the laboratory after the disinfection protocol. Fig. 8: Transparent ask for future nalisation the modelling of the superstructure. The thermoplastic mask was placed on the bar screwed into the master model; all this was repositioned on the articulator and the veneers were xed in place within the mould silicone (Fig. 16). Fig. 11: Bar seated and screwed without contacts with the soft tissues The anatomic supports for veneers were modelled in wax (Fig. 14) and then inserted inside the casting cylinder along with the investment. The cylinder was preheated to 630°C for 90 minutes, and then cooled down to 400°C and maintained at this temperature for 60 minutes A predetermined amount of polymer based on PEEK was introduced inside the cylinder and left in position for 20 minutes The cylinder was placed inside the unit for the vacuum injection system and the pressing was carried out at 4.5 bar. After cooling, the coating was removed and the superstructure obtained w a s s u b j e c t e d t o s a n d b l a s t i n g Fig. 9: Design of the bar with the attachments Fig. 12: Detail of the attachments used Fig. 15: PEEK superstructure Fig. 10: Master Model with bar and attachments Finalising the restoration The bar was placed on the model and undercuts were eliminated with wax. The housings with retentive caps were placed into position and the master model duplicated with silicone. The duplicate model was developed with class IV plaster; according to the manufacturer’s instructions. A rigid thermoplastic mask with a thickness of 1 mm was adapted over the duplicated model as the basis for Fig. 13: Try-in of bar in the patient’s mouth Fig. 14: Modelling of the superstructure Fig. 16: Positioning of the facets inside the ask (aluminium oxide, 110 pm, 2.5 bar) (Fig. 15). A primer was dabbed into the spaces of the metal housing and cured for 90 seconds then the housings were blocked with dual adhesive. The bar and superstructure were placed on the master model, inside the mue. The gap between the two structures was filled with silicone. The inner part of the veneers was subjected t o s a n d b l a s t i n g ( a l u m i n i u m o x i d e , 110 pm, 2.5 bar) and a primer was dabbed and then polymerised for 90 seconds The veneers were blocked DENTAL ASIA MAY / JUNE <strong>2018</strong> 61
Page 1:
Dental Profile: Mr. Chuck Hall - Ah
Page 5 and 6:
Rainer Wöran, AUS Amann Girrbach A
Page 8 and 9:
Giving back to Society Dental Stude
Page 10:
Giving back to Society Dental Units
Page 14 and 15: Dental Updates Convergent Dental Ex
Page 16: Dental Updates CS 8100SC 3D Wins 20
Page 20 and 21: Under the Spotlight Rockstar in Den
Page 22 and 23: Under the Spotlight Patients often
Page 24: Under the Spotlight ourselves too s
Page 27 and 28: Under the Spotlight Some may say th
Page 29 and 30: He sees DM being integrated into ot
Page 32 and 33: Dental Profile Video monitor shroud
Page 34 and 35: Dental Prole Personalising Dentistr
Page 36: Dental Prole According to Dr. Mario
Page 39 and 40: Performance. It runs in the family!
Page 41: Trefoil - the next full-arch revol
Page 44 and 45: Clinical Feature On this premise, t
Page 46 and 47: Clinical Feature development in adv
Page 48 and 49: Clinical Feature Tongue-tie (ankylo
Page 50 and 51: Clinical Feature In severe instance
Page 52 and 53: 31.5.2018 15.5.2018 IDEAS
Page 54: Clinical Feature and intra-oral vac
Page 57 and 58: Behind the Scenes in the ve Vita sy
Page 59 and 60: The 3rd “MYANMAR’S LEADING MEDI
Page 61: Behind the Scenes increase the accu
Page 66 and 67: In depth with - Renfert AUTO spin b
Page 68 and 69: Product Highlight Mectron New Perio
Page 70 and 71: PRODUCT HIGHLIGHT Ivoclar Vivadent
Page 72 and 73: SHOW REVIEW IDEM 2018 Takes Clinica
Page 74 and 75: SHOW PREVIEW INAUGURAL DENTAL AESTH
Page 76 and 77: BOOKS for SALE AFG (Anatomic Functi
Page 80: N-Cement Collection Luting material
show all

Dental Asia May/June 2018

Create successful ePaper yourself

Delete template?

Save as template?