Composite Resins Reconditioned, Behavior and Survival: Clinical Follow-up 10 Years

A cohort of 26 patients aged 18-80 years old (mean: 28.35 years; 42% men, 58% women) with 78 composite restorations (Class I: 39; Class II: 39) were recruited at the Operative Dentistry Clinic at the Dental School of the University of Chile. All participants in the refurbishing groups showed clinical features for the anantomy, roughness and/or luster that deviated from the ideal and were rated Bravo according to the modified United States Public Health Service (USPHS) criteria. New Composites with Alpha values (Replacement group) and acceptable composites (No treatment group) were used as controls. The protocol was approved by the Institutional Research Ethics Committee of the Dental School at the University of Chile (Project PRI-ODO-0207). All patients signed informed-consent forms and completed registration forms

General Inclusion Criteria:

• Patients with more than 20 teeth.
• Restorations in functional occlusion, with an opposing natural tooth.
• Asymptomatic restored tooth.
• At least one proximal contact area with a neighboring tooth.
• Patients older than 18 years.
• Patients who agreed and signed a consent form for participating in the study.
• Area outside of the restoration failure is in good condition.

General Exclusion Criteria:

• Patients with contra-indications for regular dental treatment based on their medical history.
• Patients with xerostomia or individuals taking medication that significantly decreased salivary flow.
• Patients with a high risk of caries.
• Patients with psychiatric or physical diseases, which interfered with oral hygiene.

Treatment Group Criteria Two hundred four patients were initially evaluated and assigned in accordance with the modified USPHS criteria,26 patients were selected based on the inclusion criteria with at least 1 Composite restoration with anatomy, roughness and/or luster (Bravo) suitable for reburbishing, with another composite restorations that had excellent values (Alpha) and was made at this time (Replacement group).And finally another composite pre-existing with acceptable condition (Alpha or Bravo values) acted as control. The patient was considered the statistical unit in this study (n=20).

Restoration Assessment The quality of the restorations was scored in accordance with the modified USPHS criteria. The Cohen Kappa inter-examiner coefficient was 0.74 in the first year and 0.87 after 10 years for two examiners (JM and EF) who underwent calibration training exercises each year. In the first, second, third, fourth, fifth, and tenth years, the examiners independently assessed the restorations for anatomic form, roughness, color, marginal staining,luster, secondary caries, marginal and marginal adaptation, both directly via tactile and visual examinations with mouth mirror number five and explorer number 23 (Hu Friedy Mfg. Co. Inc.) and indirectly by radiographic examination (bite wing). A third clinician (GM), who also underwent the calibration training exercises, made the final decision if a difference was recorded between the two examiners and they could not reach an agreement.

Treatment Groups Refurbishing For this group, The dentists finished the occlusal, lingual or facial surfaces of defective RBC restorations with the medium series of aluminum oxide disks (Sof-Lex,3M ESPE) or carbide burs (12 and 30 blades,Brasseler USA, Dental Instrumentation,Savannah, Ga.) and then polished them with afine series of aluminum oxide disks (Sof-Lex, 3M ESPE) and diamond-impregnated composite polisher (ComposiPro Diacomp, Brasseler). For restorations in which proximal surface areas were affected, the clinicians smoothed them with interproximal aluminum oxide finishing strips (Sof-Lex Finishing Strips, 3M ESPE).

Replacement group Composite resins with Alpha values for the marginal adaptation criteria were used as the positive control and were made with resin composite (Filtek Supreme, 3M ESPE), eith rubber dam isolation and the adhesive system L-Pop Prompt (3M-ESPE) No treatment Composite resin restorations (Z100, 3M ESPE) in general clinically acceptable, did not receive treatment.