Recent years have seen an increase in the prevalence of non-carious cervical lesions (NCCLs). As they are more common in older patients further increase are likely. Several alternatives to improve the bonding of restorations have been suggested and conditioning with ethylene diamine tetra acetic acid (EDTA) has been reported in vitro. The aim of this trial was to evaluate the influence of preliminary EDTA conditioning on the retention of composite restorations in NCCLs bonded with a one-step self-etch adhesive over the course of 18 months.

Methods

Patients with two similar-sized NCCL were selected and randomly allocated to one of two groups. 2 calibrated dentists placed the resin composite restorations using a one-step self-etch adhesive after preliminary cleaning with pumice and water. Half of the restorations were placed according to the manufacturer’s instructions. The other half has the lesion surface conditioned with 17% EDTA for 2min before adhesive application. Restorations were evaluated at baseline, 6, 12, and 18 months using FDI criteria by independent examiners blind to the allocation. Retention rate was the primary outcome, marginal adaptation and staining secondary outcomes.

Results

• The average age of the patients was 40 (range 24-56 )
• 96 restorations were placed in 48 patients.
• 54 restorations were placed in the maxillary arch, 42 in mandible. 54.2 % were placed in premolars, 33.3% in anterior teeth and 12.5% in molars

	EDTA	Control
Number of restorations at baseline	48	48
Restoration failures at 18 months	4.5%   (2/44)	25.7% (9/35)
Cumulative retention rate at 18 months	95.5%(95% CI 84.9– 98.7)	79.6%(95% CI 65.5–89.9)

• Significant deterioration of the marginal adaptation and marginal discoloration were observed for both groups over the 18-month evaluation.

Conclusions

The authors concluded:

The preliminary conditioning with EDTA before application of a one-step self-etch adhesive significantly improved the retention rates of composite restorations in cervical lesions.

Comments

This trial has a sample size calculation indicating that 44 restorations were sufficient to detect a 20% difference between the groups and a good description of the clinical intervention and assessors that were blind to the allocations. At the 18-month assessment, however, there was a higher rate of drop out in the control group than the EDTA group. Calculation of the numbers needed to treat from the data supplied at 18 months would suggest that you would need to place 5 NCCL restorations with EDTA in order to have one additional restoration survive at 18 months. If you were do a worst case scenario analysis based on all the missing filing data from the EDTA group failing and all those from the control group being retained (unlikely but possible) you would see need to place 20 NCCL restorations with EDTA in order to have one additional restoration survive at 18 months. The authors also highlight the fact that the EDTA had no impact on marginal adaptation and discoloration. We have reported on a number of reviews on the treatment of NCCLs (see links) and more research is needed to determine the best approach for managing this condition, which is increasing in prevalence.

Links

Luque-Martinez I, Muñoz MA, Mena-Serrano A, Hass V, Reis A, Loguercio AD. Effect of EDTA conditioning on cervical restorations bonded with a self-etch adhesive: A randomized double-blind clinical trial. J Dent. 2015 May 8. pii: S0300-5712(15)00107-4. doi: 10.1016/j.jdent.2015.04.013. [Epub ahead of print] PubMed PMID: 25963586.

Dental Elf – 11^th May 2015 – Cervical composite resin restorations: bevel or not?

Dental Elf – 7^th Aug 2014 – Review finds glass ionomer had lowest annual failure rate in non-carious cervical lesions

Dental Elf – 15^th Apr 2014 – Review suggests that glass ionomers had best retention rates in non-carious cervical lesions

Dental Elf – 27^th Feb 2012 – Insufficient evidence for recommendations on best adhesive system or bonding strategy for non-carious cervical lesions