Root Caries Excavation With Air Water/Powder Prophylaxis Device for ART Restorations (ART-AIRFLOW)

Excavation of Root Caries With Air-water Powder Stream vs Manual Excavation for Atraumatic Restorative Treatment in Older Patients: a Single-blind Randomized Controlled Trial

The main objective of this RCT is to compare the efficacy of a powder/water jet prophylaxis device and conventional hand excavation in excavating root surface caries, with regard to restoration survival/success in older adults. The secondary outcome of this RCT is to assess the participants' treatment preferences for the received treatment with regard to the procedures involved and in the invasiveness of the procedures carried out during the ART restoration.

An enamel hatchet will be used to create access to the carious lesion and then removal of soft carious tissue will be undertaken with excavators. Excavation will be stopped when some resistance to excavation will be felt and the cavity will be then conditioned with polyacrylic acid for 20 s, washed and dried with cotton pellets. A high-viscosity glass-ionomer cement will be used to restore the cavity. Moisture control will be achieved with the use of cotton wool rolls. A chair-side assistant will hand-mix the glass-ionomer according to manufacturers' instructions and it will be placed in the cavity using the "press-finger" technique whenever the type of cavity allows it. In the case of root restorations, a glove coated with petroleum jelly will be used similarly to the "press-finger" technique to better condense the material into the cavity. Excess material will be removed; the restoration will be coated with petroleum jelly. No local anaesthetic will be used to provide ART treatment.

An enamel hatchet will first be used to gain access into the cavity. Then the powder-water prophylaxis device will be used for the removal of soft carious tissue with the sodium bicarbonate powder-water jet. Excavation will be stopped when the colour of the lesion begins to darken and all the soft deposits are evacuated. The excavation will be done intermittently allowing sufficient time to check with hand instrument the surface hardness of the lesion. If the lesion is still soft excavation will be continued until the surface is hard suitable for restoring. The cavity will be then rinsed with copious water spray to evacuate all the powder-water material. The restoration procedure with a glass-ionomer cement will be done following the same procedures as in the control group.

The participants allocated to this group will have the caries excavated as described for the control group. Then prior to filling the excavated cavity, the procedure of sodium bicarbonate powder-water jet irrigation as described for the intervention group #1 will be performed to condition the prepared excavated cavity. Then the restorative procedure will be completed with the restorative material and procedures as described for the previous groups.

Restoration success rate (SxR %): For the purpose of this trial, a successful restoration is defined as one that has undergone no changes in its surface / structural integrity, still adhered to the structure and is functional when examined during the scheduled or unscheduled recall visit. The restoration success rate (SxR %) is calculated by the number of successful restorations present at the end of the trial (nsx) divided by the number of restorations placed in the beginning of the trial (N0) multiplied by 100 using the formula: SxR % = (nsx / N0) * 100.

Restoration survival rate (SvR %): For the purpose of this trial, any restoration, where the surface or structural integrity is compromised, but still adhering to the tooth, is functional and does not warrant a repair or replacement when examined during the scheduled or unscheduled recall visit, is considered survived. The restoration survival rate (SvR %) is calculated by the number of survived restorations present at the end of the trial (nsv) divided by the number of restorations placed in the beginning of the trial (N0) multiplied by 100 using the formula: SvR = (nsv / N0) * 100.

Secondary assessment will be to assess the participants' treatment preference. This is done by administering a simple questionnaire which inquires on their treatment preferences. After treatment will be completed the dental nurse will question the participant about their treatment preference. The questions will include preferences for restorative treatment with or without the use of anaesthesia, with or without rotary instrumentation, hand instrumentation or with air-water prophylaxis device, compared to their previous dental experience. The response "no difference" will also an option.

Inclusion criteria Adults ≥65 years Dentinal root caries lesions with no painful symptomology Can follow instructions for oral hygiene Not dependent for care for their ADLs. Exclusion criteria: Symptomatic carious teeth Non-carious attrition, erosion or abrasion cavities Periodontally compromised teeth with Grade 3 mobility, and active signs of infections. Not willing or able to sign informed consent Post-hoc exclusion: Participant withdraws consent Medical reasons.

Clinic of General, Special care, and Geriatric Dentistry, Center of Dental Medicine, University of Zurich