Evaluation of the Occlusal Effects of the Hall Technique and Investigation of Children's Satisfaction

Background: The Hall Technique (HT) is a non-invasive, easily applicable minimally invasive dentistry approach for managing dental caries in children. It involves placing a preformed metal crown over a tooth with decay, to seal it in and stop the decay from progressing. However, it alters the occlusion as no tooth substance is removed to make space for the crown.

Objective: This study, aims to evaluate the effects of Hall Technique on occlusion in children, to assess whether there are any adverse effects on the temporomandibular joint and masseter muscles, related to changes on occlusion and to evaluate the children's perceptions of the crowns.

Materials and Methods: A total of 37 children aged 5-9 years, who have not been treated with the Hall Technique previously and who have dentinal caries that did not reach the pulp (affecting the occlusal or the occluso-proximal surfaces) in their primary molars, will be invited to participate in the study. At the first visit, clinical examination will be carried out and intraoral impressions will be taken for pre-treatment evaluation. The occlusal vertical dimension of the teeth will be measured clinically with callipers. Temporomandibular joint and masseter muscles will be examined clinically. Then, the Hall Technique crown will be placed to treat the carious tooth, the impressions taken again, and measurements repeated. At one and three months following treatment with the crown, the participant will have the measurements repeated. The child and parent will complete a questionnaire after 3 months on their perception of the crown.

In the data analysis, frequency, percentage, mean and standard deviation analyses will be used for demographic data and description of the clinical data. In numerical data analysis, t-test or Mann-Whitney U test will be used according to the data distribution. Geomagic software will be used to analyse sequential study models of the teeth to measure relative changes in the tooth positions over time.

Dental caries is one of the most common chronic diseases during childhood. Due to the high incidence of dental caries in the primary dentition and inadequate treatments, early childhood caries is an important public health problem for children. The main challenge in paediatric dentistry, both for the clinician and the family, is to cooperate with the child to provide the necessary treatment successfully. Although many factors affect dental anxiety, research shows that the type of dental treatment can influence the child's behaviour. Minimally invasive dental approaches have been found to offer a more comfortable treatment process. The Hall Technique is a type of minimally invasive dental treatment. It has been used for more than 20 years to treat dental caries in children. In this technique, the carious lesion is sealed under a PMC to stop the progression of caries and prevent pain and/or infection. A crown is pressed over the tooth without local anaesthesia, tooth preparation/reduction, or carious tissue removal. This makes the technique less invasive and it can be more acceptable to children than a traditional filling involving injections and drilling.

One of the drawbacks of Hall Technique is that it increases the occlusal vertical dimension (OVD) because the PMC is placed on the tooth without any preparation. It is possible that an increase in the occlusal vertical dimension could cause hyperactivity of the masticatory muscles, an increase in occlusal forces, bruxism, and temporomandibular joint disorders. The Hall Technique has reportedly temporarily increased the vertical dimension. According to clinical research, it takes approximately a month for the vertical dimension to return its pre-treatment state.

To the best of our knowledge, none of the studies have accurately determined how the child's occlusion returns to its pre-treatment state after the placement of a Hall Technique preformed metal crown. The aim of this study is to evaluate the effects of Hall Technique on occlusion, temporomandibular joint, and masseter muscle in children and the child's perceptions of the crown.

Eligibility Criteria:
Children are eligible for inclusion if:

* they are 5 to 9 years old;
* they fit the clinical criteria to receive a HTPMC to manage primary molars carious lesions;
* they have antagonist primary molar
* they have not had a HTPMC fitted before;
* their parents can understand what is involved in the study and have signed and given assent to participate;
* they can cooperate with dental care including having a dental impression taken; and
* their parents are willing and able to bring them to the follow-up appointments 4, and 12 weeks after the treatment.

Children will be excluded from the study if:

* They do not have a parental agreement to participate; or
* They have self-reported occlusal parafunctional habits (e.g. bruxism, constantly open mouths).