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Efficiency of subgingival calculus removal with the Vector-system compared to ultrasonic scaling and hand instrumentation in vitro.

OBJECTIVE
The recently introduced Vector-system (Duerr Dental, Bietigheim-Bissingen, Germany) is recommended to be used in conjunction with different insert tips and irrigation fluids. The aim of the study was to assess subgingival calculus removal depending on the mode of operation and to compare the results to conventional methods for root debridement.


METHODS
Sixty extracted human teeth with calculus on the root surface were treated in an artificial periodontal pocket model using six methods: Vector-system with metal probe insert (VPP) or metal curette insert (VPC), both used with polishing fluid, Vector-system with metal probe insert (VAP) or metal curette insert (VAC), both used with abrasive fluid, EMS-ultrasonic system (U) and hand instrument (Gracey curette). Photographs of the root surface were taken at intervals of 10 s and calculus removal was assessed using a surface analysis software until the root surfaces were cleaned completely. Analysis of variances (ANOVA) of the ranks with subsequent comparison of mean ranks and calculation of homogeneous groups (Scheffe) were used for statistical analysis.


RESULTS
Employing the hand instrument, highest efficiency could be observed (0.340 mm2/s). Calculus removal with the Vector-system and metal probe insert (VPP: 0.036 mm2/s; VAP: 0.067 mm2/s) was less effective (p < 0.05) than using the system with metal curette inserts (VPC: 0.122 mm2/s; VAC: 0.209 mm2/s). Employing the abrasive fluid, removal of deposits with the metal curette insert was as efficient as with the conventional ultrasonic system (U: 0.199 mm2/s, p > 0.05).


CONCLUSION
The present in vitro study indicates that the efficiency of calculus removal with the Vector-system is significantly dependent on the selection of inserts and irrigation fluids.