Evaluation of proximal contact tightness of Class II resin composite restorations.

Contains fulltext : 88644.pdf (publisher's version ) (Open Access)OBJECTIVE: The objective of the current study was to compare in-vitro the proximal contact tightness (PCT) of Class II resin composite restorations (RCR) placed with different established and new placement techniques. METHODS: 105 ivorine lower left first molars with standardized MO cavities were randomly divided into seven groups (n = 15) as follows: SRing: sectional matrix and separation ring (Garrison Dental); CRing: circumferential matrix (1101-c, KerrHawe SA) with separation ring; CWedge: circumferential matrix with a wedge only; COptra: circumferential matrix and OptraContact (Vivadent); CCerana: circumferential matrix and a Cerana insert (Nordiska Dental); CElliot: circumferential matrix and Elliot separator (PFINGST & Co) and Walser: Walser matrix O-type (Dr Walser Dental GmbH). In all the groups, the matrix band was secured using a wooden wedge except for the Walser group, following manufacturer's recommendations. A Tofflemire retainer (Kerr Corporation) was used to apply the circumferential matrix band whenever it was used. All the prepared teeth were restored with resin composite (Premise, Kerr) mounted in a manikin head to simulate the clinical environment. PCT was measured using the Tooth Pressure Meter (University of Technology, Delft). The data were analyzed using one-way ANOVA and Tukey post-hoc tests (p < 0.05). RESULTS: Compared to the control group (SRing) (6.64 +/- 1.06N), all other systems resulted in significantly lower PCT values (p < 0.001). Within the circumferential matrix groups, CRing (4.01 +/- 0.53N) and CElliot (4.29 +/- 1.08N) showed significantly tighter contacts compared to the CWedge (0.37 +/- 0.22N), COptra (0.91 +/- 0.49N), CCerana (2.99 +/- 1.98N) and Walser (1.34 +/- 0.55N) (p < 0.05) group. Between CWedge and COptra, no significant difference was found (p = 0.57). CONCLUSION: The use of separation rings with sectional matrices provides superior contacts when placing Class II RCRs

Creating tight proximal contacts for MOD resin composite restorations

Item does not contain fulltextOBJECTIVE : The purpose of this study was to compare proximal contact tightness (PCT) of MOD resin composite restorations placed with different matricing protocols. METHODS : Forty-five ivorine lower right first molars with standardized MOD cavities were equally divided into three groups according to the restoration protocol. Group 1: Sectional matrix (Standard matrix, Palodent, Dentsply) secured with a wedge (Premier Dental Products Co.) and separation ring (BiTine I, Palodent, Dentsply, York, PA, USA) was used to restore the mesial surface first and then removed and repeated for the distal surface. Group 2: Identical to group 1, but separation rings were placed at both the mesial and distal sides (BiTine I+II, Palodent) prior to restoration. Mesial surface was restored followed by distal. Group 3: Walser matrix (O-form, Dr. Walser Dental GmbH) was used. Following composite resin restoration, PCT was measured using the tooth pressure meter. Data were analyzed using analysis of variance and a Tukey post hoc test (p<0.05). RESULTS : PCT values for mesial contacts were 2.99 +/- 0.47N for group 1, 4.57 +/- 0.36N for group 2, and 3.03 +/- 0.79N for group 3. For the distal contacts, the values were 4.46 +/- 0.44N for group 1, 5.12 +/- 0.13N for group 2, and 0.76 +/- 0.77N for group 3. Significantly tighter contacts were obtained for mesial and distal contacts for group 2 compared to groups 1 and 3 (p<0.05). For groups 1 and 3, mesial contacts were not significantly different (p=0.993), while distal contacts for group 1 were significantly tighter (p<0.001). CONCLUSION : Within the limitations of this study, tighter contacts can be obtained when sectional matrices and separation rings are applied to both proximal surfaces prior to placement of the resin composite in MOD cavities