Maximizing Hydraulics

"This case illustrates the complexity of the root canal system when just one major canal is treated."

Stephen Kane, DDS
Berkeley, CA


This case, in which a single rooted upper right second bicuspid was treated, might be considered a simple, straightforward procedure, yet the complexity of its anatomy refutes this assessment. According to Clifford J. Ruddle, “Central to successful endodontics is knowledge, respect, and appreciation for root canal system anatomy and careful, thoughtful, meticulously performed cleaning and shaping procedures.”

The patient’s general dentist relieved her acute pain by performing caries removal along with any remaining pulp chamber tissue. Subsequently, she presented with minimal symptoms when she was treated in my office.

Chief Complaint: #4 acute pain to touch.

Exam/Diagnosis: Initial treatment by the general dentist alleviated the patient’s discomfort. The radiograph showed extensive decay into the pulp space, a loss of apical lamina dura, normal trabecular pattern and normal periodontal ligament space. There was slight sensitivity to percussion. No tenderness to palpation was observed.

Pulpal Diagnosis: Necrotic.

Periapical Diagnosis: Acute apical periodontitis

Treatment Options: No treatment, root canal therapy, extraction

Treatment: After the patient was anesthetized and the tooth was isolated with a rubber dam, the access prep was performed using a ProTaper Universal SX followed by Gates Glidden drills size #3 and #4. After establishment of a glide path using a #10 hand file coated with ProLube root canal conditioner, and verified radiographically, the working length was determined. After further enlarging the glide path with a #15 hand file, rotary instrumentation was initiated. The canal was cleaned and shaped using ProTaper Universal rotary files sizes S1 through F3 with intermittent Sodium Hypochlorite irrigation. After completion of shaping with the F3 ProTaper Universal, a gutta-percha cone was fit to the working length and verified with a radiograph. A final E.D.T.A. rinse was performed, the canal dried and the F3 cone cemented with root canal sealer.

Hydraulics were optimized by first using a size .08 plugger seated to a depth 6 mm short of the apex. This was followed by an aliquot of gutta-percha delivered with a backfill device and allowed to cool. A second insertion of a plugger, this time using size 1.2 mm, was driven to a depth of 12 mm short of the apex maximizing hydraulic effects in the mid-root. The remaining superior portion of the canal was filled using additional aliquots of gutta-percha condensed with hand pluggers.


"This case illustrates the complexity of the root canal system when just one major canal is treated. Through the copious use of irrigating solution to dissolve remaining organic material in the canal system, combined with a two-step application of sequentially larger pluggers, the lateral canals were effectively treated." 


Dr. Kane has been practicing dentistry for more than thirty years. Dr. Kane attended UCLA and UC Berkeley as an undergraduate. He received a B.A. from UCLA then continued on to receive his dental degree from the UCLA School of Dentistry. He was a clinical professor at the UCSF School of Dentistry from 2003 thru 2009. In 2006 he was awarded outstanding clinical professor by the graduating class. Although he enjoys all aspects of dental care, he felt most satisfied when performing root canal therapy and has now devoted himself completely to this specialty. The advancements in knowledge coupled with new technologies make root canal therapy very satisfying to the practitioner and most important, beneficial to our patients. Modern endodontic therapy routinely offers excellent clinical outcomes even in challenging cases.

Dr. Kane enjoys his family, photography, travel and seeing the world on his motorcycle.