Bonding significantly increased sealant retention

Fissure sealants have been in use since the 1960s and there is good evidence from a Cochrane review to recommend their use (Dental Elf 8^th Apr 2013). Their effectiveness is related to retention rates with complete retention seen in around 80% of resin-based sealants at 12-24 months.

The aim of this study was to determine if the addition of an ethanol-based etch-and-rinse primer and adhesive system significantly improved sealant retention after 1 year and if the patients’ behaviour had an effect on retention.

Methods

Children aged 5-15 with paired fully erupted, maxillary or mandibular FPMs were recruited. One trained operator placed all the sealants; the matching arch-paired FPMs were randomly designated to receive a bonded sealant (study group) or a conventional sealant (control group); teeth were randomised using a coin toss.

Sealants were placed using a standardised technique. Child behaviour was scored using the 4-point Frankl Behaviour Rating Scale. Sealants were scored by two trained and calibrated blinded examiners as intact, partially intact, or not intact for each surface (occlusal, palatal and buccal). Partially intact and missing sealants were grouped together during statistical analysis.

Results

112 patients were recruited with 424 erupted first permanent molars (848 surfaces)
9 patients (32 sealants) were lost to follow up.
Intact sealants at 12 months (195 teeth)

	Bonded sealants	Control sealants	Fisher’s exact test
Overall retention	92%	79%	P = 0.0005
Occlusal	98%	93%	P = 0.08
Buccal/palatal	92%	82%	P = 0.0005

Intact maxillary sealants at 12 months (97 teeth)

	Bonded sealants	Control sealants	Fisher’s exact test
Overall retention	96%)	75%)	P = 0.0001
Occlusal	100%	93%	P = 0.03
Buccal/palatal	95%)	75%)	P = 0.0004

Intact mandibular sealants at 12 months (98 teeth)

	Bonded sealants	Control sealants	Fisher’s exact test
Overall retention	89%	84%,	P = 0.41
Occlusal	97%	92%	P = 0.22
Buccal/palatal	89%	87%	P = 0.83

The higher the participant’s behaviour score (Frankl Behaviour Rating Scale), the greater the number of intact sealants recorded at 12 months (P = 0.0001).

Conclusions

The authors concluded: –

This study has shown that addition of an ethanol-based bonding agent significantly increases the retention of resin sealants on FPMs at 12 months on all surfaces. We therefore advocate routine use of bonded sealants using an ethanol-based bonding agent on maxillary first permanent molars, especially on the palatal surface.

Comments

While the clinical procedures for sealant placement is well described, a coin toss is used to randomise arch, tooth and bonding in this trial, which is less than optimal and at greater risk of bias. Drop rate is low at just 8% with retention rates at 12 months even for the control sealant matching the approximately 80% rate reported in the Cochrane review. The study found a significant improvement in retention rates at 12 months and it will be interesting to see if this benefit persists for longer.