John A. Khademi, DDS, MS
Context
Despite decades of accumulated trial and observational evidence, the treatment objectives and end-points for endodontics remain highly controversial. Within the framework of conventional instrumentation endodontics (CIE) the consensus of opinion requires some form of enlargement of the canal, apical foramen or both, increasing the risk of procedural complications and compromising structural integrity. Minimally invasive endodontics (MIE) seeks to reduce or eliminate these risks and compromises by using a multi-sonically activated irrigation.
Objective
To assess the in-vivo efficacy and safety of a new procedure instrument and technique for minimally invasive endodontic treatment.
Design
A single-site, single-arm trial with a mixture of bicuspid and molar teeth with vital and necrotic pulps, and a range of symptoms. Clinical and radiographic findings from a total of 74 teeth treated with the Sonendo® GentleWave® CleanFlow™ Procedure Instrument.
Interventions
Participants received minimally accessed and minimally invasive endodontic treatment with no instrumentation/file sizes larger than SS White® 20/V.06, with most cases at 17/V.04 or smaller. All teeth were completed in a single visit and restored at that visit.
Main Outcome Measures
The primary outcome measure was tooth survival as measured by asymptomatic functional retention of the tooth with no clinical signs, nor increase in radiographic findings at CBCT. Secondary outcome measures were radiographic evidence of resolution of apical periodontitis at CBCT (3 mo, 6 mo, 12 mo & 24 mo), intra-operative and post-operative pain and failure of the GentleWave Procedure, as measured by need for additional intervention such as revision (conventional or surgical) or extraction.
Results
Safety
There were no adverse events during treatment. No patients experienced pain during treatment. Asymptomatic patients were largely asymptomatic at one, two and seven days post-op. Symptomatic patients had dramatic pain relief within 24-48 hrs. No patients were symptomatic at three months.
Tooth Survival
Of the 74 teeth initially treated, none were lost-to-follow-up at three months, increasing to a total of seven lost-to-follow-up at two years (90% recall, 10% lost-to-follow-up at two years). Of the 67 teeth available for follow-up at the two-year period, 66 (98.5%) were retained and one was extracted. Of the 74 teeth initially treated, three teeth (4%) were identified with persistent sinus tract at the three-month follow-up and revision attempted, which successfully resolved the sinus tract on two; both of which were retained.
Radiographic Findings
All teeth presenting with radiographic findings improved through the period studied, including those that were eventually lost-to-follow-up. No teeth without radiographic findings developed radiographic findings through the period studied, including those that were eventually lost-to-follow-up.
Conclusions
The GentleWave Procedure using the CleanFlow Procedure Instrument combined with minimal instrumentation led to 71 of the 74 teeth (96%) successfully treated with the CleanFlow Procedure Instrument alone at three months. All three cases failing the GentleWave Procedure were identified at three months, and were long-standing sinus-tract cases with moderate to large radiographic findings, two of which responded to revision. There were no known failures, extractions or revision needs occurring in the cases followed from the three-month follow-up to the study completion at two years. With the low lost-to-follow-up, this suggests high effectiveness of the GentleWave Procedure with minimally invasive treatment, and that revisable failures occur early.
