Super Sectional Matrices and Super Composites: Use of Garrison’s Composi-Tight 3D Fusion Wide Prep (FX600) in a Complex Composite Reconstruction with Voco Grandio SO
A 72-year-old healthy woman presented to the practice with a chief concern of food trapping between teeth 31 and 32. Tooth 30 was missing, and there was evident mesial tipping and drift of the tooth 31 relative to tooth 32. The patient wished to have the diastema closed. Clinical assessment of the tooth revealed the presence of a large DOL composite restoration with the offending gap as well as a small hairline fracture verticoaxially on the tooth sructure lingual cavosurface immediately adjacent to the restoration. The tooth had no symptoms. Various treatment options were discussed, including a bonded minimal prep full coverage restoration as the surface area of the restoration approximated 65% of the total. This was ruled out as a prudent option as the patient did not have any prosthesis to prevent further mesial drift of tooth 31, and hence a pragmatic solution was to replace the restoration with an attempt to restore firm centric contacts with no lateral excursive interferences. This would give the highest likelihood of preventing further mesial drift as well as load the composite in compression where it is stronger, relative to flexion or tension where it is weaker.
Procedure
Full rubber dam isolation was completed following profound local anaesthesia via inferior alveolar nerve block using 2.2mL of a 2% Lignocaine with 1:100,000 epinephrine solution. The restoration was excavated, and the vertical hairline fractured segment easily released with just a touch of the bur. Caries detector dye (Kuraray) was utilized. The cavosurface margins were bevelled (as one cannot bond to the lateral aspects of enamel rods, only to the ends) and the preparation micro air abraded using a 27 micron aluminum oxide powder at 30-40 psi or 2-3 bar of pressure. The resulting restoration was extremely large and featured extension on the lingual to virtually the mesiodistal midpoint of the tooth. A Garrison Slickband (FX175) was placed and the small blue 3D Fusion wedge (FXBL) placed snugly in the cervical embrasure space prior to the placement of the Wide Prep ring (FX600). This ring was stable in position even when placed superior to the rubber dam clamp with a firm separating force delivered to the area. A total etch technique was utilized and Optibond Solo Plus (Kerr, Orange County, CA) scrubbed into the preparation and marginal areas for 30 seconds before air thinning, evaporation of the solvent and light curing. 3 ultra-thin horizontal increments of 0.25mm each (Grandio SO flow, A2, Voco GmbH) were placed on the proximal box floor to hybridize the bond layer and ensure maximum bond strengths to the dentin and enamel. Other reasons for the placement of ultra-thin layers are not only to ensure complete polymerization, but also increased microtensile shear bond strength in the area which is responsible for the majority of clinical failures in Class II cases. The average depth from marginal ridge to proximal box floor in mandibular molars averages 6mm. With the matrix assembly in place, it is hard to get as close as possible and to achieve the best angle for curing down to the base of the proximal box floor. The ideal angle in this case is not from the patient’s left side, but by the operator. Following placement of these initial three microlayers, the composite was layered in horizontal increments measuring 1mm high each until completion of the ridge (Grandio SO, A2, Voco GmbH). The matrix assembly was removed at this point before completion of esthetic, incremental occlusal layering using Grandio SO (A2 shade, Voco GmbH).
Removal of the matrix assembly before completion of occlusal layering allows both visual and tactile testing of the contact morphology and strength. The literature speaks to the ideal re-creation of a contact if it reproduces nature in four areas: location of the contact area, proximal contour, contact tightness and cervicomarginal adaptation (1). If the contact is loose or less than ideal, atleast clinical time and effort has not been expended in completing the occlusal aspect, only to destroy it again. It also allows an opportunity for both operator and assistant to “blast” the restoration with curing lights simultaneously from both buccal and lingual aspects, ensuring maximal polymerization before continuing. Conversion of a Class II to a Class I allows not only better instrument access for esthetic lobing or layering, it also allows a more ideal angle of curing light to access the restoration. Remember that composite cures completely with 20,000 J/cm2. Compromising factors often are the use of untested or unregulated lights, often purchased for bargain prices overseas. Another compromising factor for your restoration is if your assistant happens to be curing the rubber dam, or cotton roll. It’s not a good day for your dental assistant.
In this case, the Wide Prep ring allowed efficient contact point anatomical recreation and morphology of the missing cusp simultaneously, and minor tweaks to the occlusal outline form were completed easily with freehand manipulation of composite on the distolingual aspect of the axial wall. This restoration was completed from start to finish in 60 minutes and could not have been possible without the use of the Garrison Composi-Tight 3D Fusion Wide Prep Sectional Matrix System.
Biomimicry made easy and efficient – thanks Garrison!
Clarence Tam, HBSc, DDS, FIADFE, AAACD
Cosmetic and General Dentistry
18 Morrow Street
Newmarket, Auckland 1052
www.clarencetam.co.nz
Chairperson
New Zealand Academy of Cosmetic Dentistry
www.nzacd.co.nz
Reference
1) Raghu, R. and Srinivasan, R. Optimizing tooth form with direct posterior composite restorations. J Conserv Dent. 2011. Oct-Dec;14(4):330-336.
Review Points when removing Matrix System after Converting Class II to a Class I:
1) Check to ensure adequate contact position and strength before “committing” to the rest of the harder esthetic layering.
2) By removing the sectional matrix assembly, I have better visual and physical access for accurate layering with unimpeded access for instruments.
3) Occasionally the matrix assembly restricts the curing light position from being as close as it could be, like in this tooth 31MOL situation where the clinician has the ideal curing angle from the right side with the assembly in place. If an assistant were to want to cure like mine always does, she would have to stretch over the patient with her left hand to achieve the right angle, otherwise her curing angle would be too mesial and would not hit the base of the proximal box floor, which in mandibular molars is an average of 6mm from marginal ridge to proximal box floor. Now if the matrix is in the way and you have an elevated position, how confident are we that to cure the composite requiring 20,000J/cm2 we can hit the base of the proximal box floor to get those first few layers.
