Dr Hussein S Patanwala explores how Stela, a self-cure bulk fill composite from SDI, offers a fast, reliable, affordable alternative to amalgam restorations in everyday dentistry.
The art of dentistry is highly skilled, with increasing expectations from both our patients and the profession.
The aesthetic demands and pressures of the Minimata Convention on Mercury in 2013 have led to a steady decline in the use of dental amalgam. The pressure is to find a viable alternative to amalgam to be used in “everyday dentistry”. Many clinicians working outside the government-subsidised NHS dental care system have been practising amalgam-free dentistry for many years. The everyday use of resin composites in the anterior and posterior areas has led to numerous innovative solutions to the general restorative problems. One such problem is the requirement from the clinician for an easy-to-use, affordable material with a low polymerisation shrinkage that could be placed in one deep increment rather than several oblique layers respecting the “C-Factor”.
One of the most recent materials to be released is Stela, a self-cure bulk fill resin composite material from SDI. This material provides an innovative upgrade to contemporary resin composites. Stela addresses the uncertainty associated with the degree of light-activated polymerisation of bulk fill composites. It is easy to use, reduces chair time, and is a potentially viable alternative to amalgam restoration for the busy NHS clinic.
Figure 1: Bitewing radiograph showing the presence of a radiopaque lining material under the amalgam restoration on the LR5
Figure 2: LR5 Amalgam restoration with defective margins, buccal horizontal fracture and mesial caries
Figure 3: Quadrant rubber dam isolation. Winged clamp LR7, double loop floss ligature LR5 and wedjet placed on the mesial of the LR3
Figure 4: Amalgam removal, old lining visible
Patient presentation
A 65-year-old patient attended with a failing amalgam restoration on the lower right second premolar (Figs. 1 and 2). The patient was anxious about dental treatment, particularly with the suggestion of using rubber dam isolation, and was concerned about how long the treatment would take and the cost.
Treatment options and planning
A holistic patient assessment was performed, including diet analysis, oral hygiene, occlusal assessment, and questions regarding the patients’ concerns about dental treatment.
The plan to remove the amalgam and restore the tooth in a time-efficient way using Stela was considered and accepted. A proposal to provide cuspal protection in the future was also discussed and consented.
Treatment details
The tooth was isolated with quadrant dam placement secured with a winged molar clamp placed posteriorly and a ‘wedjet’ (Coltene) anteriorly (Fig .3). The dam was inverted and guided into the sulcus using a steady air flow from the triple air syringe and an Applica (LM) instrument. To secure the dam in this deep position, a double-loop self-tightening floss ligature was used.
The amalgam filling, followed by the peripheral, then deep caries, was removed using a combination of diamond/tungsten carbide burs, ultrasonics and 29μm Al2O3 air abrasion from an Aquacare (Velopex) twin machine (Figs. 4 and 5).
Figure 5: Peripheral caries and unsupported enamel removed
Figure 6: Demonstration of the issue of poor adaptation when using a circumferential matrix
Figure 7: Sectional matrices trimmed and adapted. The ring placement enhanced with PTFE
Figure 8: Single increment of Stela self-cure composite
Due to the depth of the cavity and the angulation of the tooth, the Halo (Ultradent) sectional matrices (4.5mm) were customised, and PFTE tape was used to better adapt the ring and the matrix. These steps are critical to correctly and efficiently placing any resin composite. Photography, which is utilised throughout every restorative procedure, confirmed an adequate matrix seal at the cavity base.
The cavity smear layer was removed and dried. Step one involved applying Stela primer containing 10-MDP and initiators to the cavity – a process that takes less than 10 seconds (note this is a self-cure product, so light activation is unnecessary).
Stela comes in two delivery capsule variants: 55% vol. filler and the automix, which has 36% volume filler. Step two, the Stela capsule was dispensed into the cavity in a single homogenous increment (Fig. 8). The material sets quickly. After four minutes, A.S.A.P. (Clinicians Choice) was polished to achieve the final result (Fig. 9). A small amount of brown tint was used purely as a contrast from the case photography.
Figure 9: Completed restoration
Figure 10: Completed restoration with GHM 12μm Occlusion Foil assessment
Outcome and follow-up
Following the procedure, the patient was advised to have an indirect restoration with cuspal protection due to the strategic position of the tooth and its involvement in group function during lateral excursions.
Treatment conclusions
Stela is a simple and easy-to-use material that produces predictable results quickly. Is this the answer to finding a viable, cost-effective alternative to amalgam?
Discover more about Stela here, or get in touch to book a Lunch & Learn and explore how Stela can transform your dental practice.
Dr Hussein S Patanwala BDS, MSc, MFGDP UK, MFDS RCS Eng, MJDF RCS Eng, DipRest, CRDP, DipAMID, PGCMEd, FCGDent, FHEA
Dr Hussein S Patanwala is a clinical lead at a well-respected Birmingham clinic and former clinical lecturer at the University of Birmingham School of Dentistry. He trained at UCL Eastman and King’s College London. He has been awarded membership from three Royal College of Surgeons faculties. An international lecturer, his focus is in fixed prosthodontics, adhesive and minimal intervention dentistry. He is also a key opinion leader for leading dental manufacturers.