A Primary Care Randomized Controlled Trial of Hall and Conventional Restorative Techniques

Abstract

Objectives: To investigate treatment outcomes of different restorative techniques undertaken by dental therapists for primary molar carious lesions in a sample of children in New Zealand primary care. Methods: This was a randomized controlled trial with children aged 3 to 8 y in New Zealand’s Whanganui region. Children meeting inclusion criteria were randomly allocated to treatment with either the Hall technique (HT), in which a stainless-steel crown (SSC) is placed without any carious tissue removal or tooth preparation, or a non-Hall conventional restorative approach (NHT), including tooth preparation with selective carious tissue removal; this included SSC, amalgam, composite, or glass ionomer cement (GIC) restorations. Restorative outcomes after 12 and 24 mo were categorized as success, minor failure, or major failure. Results: Of the 295 eligible children, 149 and 146 were allocated to the HT and NHT groups, respectively, with a total of 570 carious primary molars treated by 13 dental therapists. The participant follow-up rates at 12 and 24 mo were 95% and 91%. SSCs were the most commonly used restoration in the NHT group (60%), followed by GIC (28%). SSCs were the most successful restorations regardless of whether they were placed with the HT or NHT, with success rates of 89% and 92% at 12 mo and 85% and 86% at 24 mo. In the NHT group, the treatment material was a predictor of minor failure at 12 and 24 mo, with significantly more failures with GICs. Conclusions: SSCs placed by dental therapists are a highly successful restoration for the primary dentition, regardless of whether they are placed with the HT or conventionally. The high failure rate of glass ionomer restorations means that they cannot be recommended for widespread use in New Zealand primary care (Australian New Zealand Clinical Trials Registry, ACTRN12614000844640). Knowledge Transfer Statement: The findings of this study can be used by policy makers and clinicians when deciding on which materials and which approach to use to maximize success and to minimize retreatment rates when providing restorative treatment for carious primary molars in children’s primary oral health care. Results also suggest that undertaking research in the primary care setting may enhance translation of new knowledge and techniques into clinicians’ hands.

Hall technique for primary teeth: A systematic review and meta-analysis

“…( Fig. 3 B) This was supported by the other studies not included in the meta-analysis [22] , [23] . However, when compared only against conventional PMCs [18] , [21] , HT showed similar success rates (RR 1.02 [95 % CI: 0.90–1.15], I 2 =52.3 %, p = 0.148).…”

“…Four of the studies included were judged to be of low risk of bias overall [17] , [18] , [19] , [20] , with the rest judged to be of high risk of bias [21] , [22] , [23] , [24] . The largest contribution of bias occurs with the randomisation process, with some studies randomising at subject level but reporting results at tooth level, introducing significant bias to the results.…”

“…The eight included studies [8] , [17] , [18] , [20] , [22] , [23] , [24] examined children aged from 3 to 10 years over a period ranging from 12 to 60 months. The setting of the studies ranged from being conducted in classrooms without dental facility by dental students [17] , primary care facilities by dental therapists [23] , general practice units by general dentists [19] , [24] , and University clinics conducted by paediatric dentists/residents [18] , [20] , [21] , [22] . Most included only teeth with multisurface lesions into dentine, with the exception of two studies including some teeth with enamel lesions [21] , [23] and three studies including some teeth with single surface (occlusal) lesions [19] , [21] , [24] .…”

“…Three of the studies randomised and analysed one tooth per subject [17] , [18] , [20] . Two studies randomised at subject level and included one or more teeth per subject [23] , [24] , while the other three studies were split mouth studies with two including two teeth (control and intervention) per subject [19] , [21] and the other including two or more teeth per subject [22] . Due to these differences in the unit of randomisation and the unit of analysis reported, only five studies were included in meta-analyses, the three studies with unit of randomization at tooth level with one included tooth per subject [17] , [18] , [20] and the two spilt mouth studies with only two teeth per subject [19] , [21] .…”

“…This may be the result of the higher failure rate of ART in multi-surface restorations. For the studies not included in the meta-analysis, [22] , [23] , [24] HT had a success rate ranging from 85 % to 93 %.

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