Clinical Oral Investigations

, Volume 23, Issue 2, pp 519–527 | Cite as

Tooth sectioning for coronectomy: how to perform?

  • József SzalmaEmail author
  • László Vajta
  • Lajos Olasz
  • Edina Lempel
Original Article



The aim of this study was to determine the increase in heat production, preparation time, and cutting surface quality of conventional, high-speed rotating instruments and piezoelectric preparation for coronectomy procedures.

Materials and methods

One hundred intact extracted molars were sectioned horizontally, sub-totally, 1 mm under the cemento-enamel line with five methods: (1) tungsten carbide torpedo (TcT), (2) round (TcR) drills using a conventional speed surgical straight handpiece (< 40,000 min−1), (3) tungsten carbide fissure (TcF), (4) diamond torpedo (DT) drills using a surgical high-speed, contra-angle handpiece (~ 120,000 min−1), or (5) a saw-like piezoelectric tip (PT). Temperatures, preparation times, and cutting surface irregularities were registered and the differences were analyzed with ANOVA, Tukey’s HSD post hoc test (temperature, time) and with chi-square test (irregular surface).


Rotating instruments produced a maximal temperature increase of less than 1 °C. TcF produced the least heat (ΔT = − 3.92 °C to the baseline), while PT produced significantly the highest temperature increases (ΔT = 12.38 °C, p < 0.001). Tungsten carbide drills were the fastest for coronectomy (from 55.9 to 64.3 s), while DT (169.7 s) while PT (146.8 s) were significantly slower. TcT and TcR drills produced an irregular root surface more frequently.


During coronectomy, rotating instruments produced entirely acceptable heat, while PT produced unacceptable temperatures. Tungsten carbide drills performed coronectomies effectively, but the diamond torpedo and PT seemed clinically questionable. Considering heat, speed, and the cutting surface quality simultaneously, TcF in a surgical high-speed handpiece seems to be the best choice for coronectomy.

Clinical relevance

The correct insert can significantly reduce excessive heat and operation time during coronectomy procedures.


Third molar Coronectomy Temperature Tungsten carbide drill Diamond drill 



We would like to thank Dr. Bálint Lovász for the language corrections. The present scientific contribution is dedicated to the 650th anniversary of the founding of the University of Pécs, Hungary.


This study was supported by the Hungarian Dental Association-NSK (MFE-NSK) “Young Researcher” grant and the Bolyai János Research Scholarship (BO/00074/16/5) of the Hungarian Academy of Sciences.

Compliance with ethical standards

Conflict of interests

The authors declare that they have no conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent

For this type of study, formal consent is not required.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Oral and Maxillofacial SurgeryUniversity of PécsPécsHungary
  2. 2.Department of Restorative Dentistry and PeriodontologyUniversity of PécsPécsHungary

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