The Hall Technique and conventional restorative treatment in New Zealand children's primary oral health care - clinical outcomes at two years.

Background: New Zealand children's oral health care is mostly provided in primary care oral health clinics. Little is known about treatment outcomes.

Hypothesis/aim: To investigate different treatment outcomes of primary molar carious lesions in a sample of children in primary care.

Design: Quasi-experimental study of 180 5- to 8-year-old children. Each child had one carious primary molar treated by a dental therapist with a plastic restorative material (PRM) or a pre-formed stainless steel crown placed with the Hall Technique (HT). After 2 years, restorative outcomes were categorised as success, minor failure, or major failure. Data were analysed using Chi-square tests.

Results: A total of 147 (82%) children were followed up; mean follow-up period 25 months (range: 21-35 months). Failure was observed significantly more in the PRM group (32%) than the HT group (6%). When baseline carious lesions were radiographically deep with marginal ridge breakdown (MRB), there was a higher proportion of major failures than when they were shallow without MRB (33% and 1%, respectively; P < 0.001). Among the deep lesions, those treated with the HT showed better success than PRM.

Conclusions: There was a much higher success rate in the children treated with HT than PRM. Deep carious lesions responded better to HT than PRM.