Effect on dental pulp of different methods of cavity preparation

ISRCTN ISRCTN17017801
DOI https://doi.org/10.1186/ISRCTN17017801
Secondary identifying numbers 145/2007
Submission date
29/08/2018
Registration date
21/09/2018
Last edited
06/11/2019
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Oral Health
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data
Record updated in last year

Plain English Summary

Background and study aims
Dentist aim to keep the pulp of the tooth (the soft tissue inside the tooth) alive. When a tooth with decay is being prepared for a filling, the pulp can be damaged by substances released by inflamed cells and bacteria, drilling and heat. The aim of the study was to investigate the pulp response to cavity preparation using an ultrasonic device in comparison with a conventional high-speed burr drill preparation using different sealing materials.

Who can participate?
Patients under orthodontic treatment who require premolar tooth extraction as part of their orthodontic treatment.

What does the study involve?
Participants were non-randomly allocated in five groups. Groups 1 and 2 received cavity preparations with high-speed rotation and sealing procedures. Groups 3 and 4 received cavity preparations with an ultrasonic device and the same sealing procedures as in groups 1 and 2. Group 5 did not receive cavity preparation. These intact premolars were used as controls. Finally, teeth were extracted according to the postoperative experimental periods: immediately, 7 and 30 days after the cavity preparation under local anesthesia.

What are the possible benefits and risks of participating?
Participants were able to benefit from having their premolar teeth extracted. There may be some risks such as some discomforts related to the anesthesia sensation, cavity instrumentation or sealing techniques. In cases of pain in the patient, the tooth was extracted.

Where is the study run from?
Bauru Dental School, University of São Paulo, Brazil

When is the study starting and how long is it expected to run for?
February 2008 to December 2008

Who is funding the study?
Department of Restorative Dentistry, Endodontics and Dental Materials of Bauru, Dental School, University of São Paulo (Brazil) and Postgraduate Research Support Program of Coordination for the Improvement of Higher Education Personnel of Brazil (PROAP-CAPES).

Who is the main contact?
Lourdes Chiok-Ocaña, lourdeschiok@usp.br

Contact information

Prof Lourdes Chiok- Ocaña
Scientific

Al. Dr. Octavio Pinheiro Brisola 9-75
São Paulo
17012-901
Brazil

ORCiD logoORCID ID 0000-0002-7760-5281
Phone +55 (0)14 3235
Email lourdeschiok@usp.br

Study information

Study designNon-randomised interventional study
Primary study designInterventional
Secondary study designNon randomised study
Study setting(s)Hospital
Study typeTreatment
Participant information sheet Not available in web format.
Scientific titleHistological evaluation of the human pulp response to different cavity instrumentation and restorative techniques
Study hypothesis1. There will be no differences in pulp response between two types of cavity instrumentation.
2. There will be no differences in pulp response between two types of cavity sealing.
Ethics approval(s)Bauru Dental School Ethics Committee, 13/12/2007, Protocol number: 145/2007.
ConditionDental pulp injury following cavity preparation
InterventionParticipants were allocated in 5 experimental groups. Groups 1 to 4 received local anesthesia with adrenaline (4% Articaine), rubber dam isolation and deep class V cavities as follows:
Group 1: Class V cavity preparations with high speed rotation on intact premolars sealing with gutta-percha as a insulator and glass ionomer cement.
Group 2: Class V cavity preparations with high speed rotation on intact premolars, application of etch and rinse adhesive system then, sealing with gutta-percha as a insulator and glass ionomer cement.
Group 3: Class V cavity preparations with ultrasonic device on intact premolars sealing with gutta-percha as a insulator and glass ionomer cement.
Group 4: Class V cavity preparations with ultrasonic device on intact premolars, application of etch and rinse adhesive system then, sealing with gutta-percha as a insulator and glass ionomer cement.
Group 5: intact premolars as a control group.
Finally, teeth were extracted according to the postoperative experimental periods, immediately, 7 and 30 days after the cavity preparation under local anesthesia and fixed in 10% phosphate-buffered formalin solution for 48 hours. Subsequently, the teeth were decalcified in 4% EDTA (Titriplex III, Merck) solution (pH 7.4) and submitted to histological procedures. Five-micrometer thick serial sections were cut parallel to the main vertical axis of the tooth throughout the cavity preparation, stained with hematoxylin and eosin (H&E) and Brown and Brenn (B&B) and analyzed under an Olympus BX50F4 light microscope. Each series of tooth sections were blind analyzed by one experienced examiner and the data of all morphological features of the pulp tissue were fully recorded.
The volume densities or the fractions of pulp volume occupied by the odontoblasts, collagen fibers and fibroblasts, ground substance, blood vessels, inflammatory process and tertiary dentin adjacent to the cavity preparation was performed with the point-counting relative volumetry method using a 100× immersion objective and a Zeiss Kpl 8× eyepiece containing a Zeiss II integration grid (Carl Zeiss GmbH, Jena, Germany) with 100 points in a quadrangular area. In ten sections per tooth, the grid was successively superimposed on 12 histological fields per section at three different pulp levels. The points that were superimposed on each cell or structure (Pi) were counted and the total number of points (Pt) was obtained. Volume density (Vvi) was calculated by the equation: Vvi = Pi/Pt.
The remaining dentine thickness (RDT) between the cavity floor and the pulp chamber was measured. For each tooth, five histological sections with less RDT were selected. Images of the remaining dentin were captured in a video camera AxioCam HRc (Carl Zeiss MicroImaging GmbH, Göttingen, Germany) coupled to an Axioskop II microscope (Carl Zeiss, Oberköchen, Germany) with 10× objective and analyzed using the AxioVision Release 4.7.2 software (Carl Zeiss Vision Imaging Systems, Oberköchen, Germany). The RDT of each group was the average of the RDT of each specimen.
Intervention typeProcedure/Surgery
Primary outcome measureMorphological features of the pulp tissue. The teeth were extracted according to the postoperative experimental periods, immediately, 7 and 30 days after the cavity preparation under local anesthesia and fixed in 10% phosphate-buffered formalin solution for 48 hours. subsequently, the teeth were decalcified in 4% EDTA (Titriplex III, Merck) solution (pH 7.4) and submitted to histological procedures. Five-micrometer thick serial sections were cut parallel to the main vertical axis of the tooth throughout the cavity preparation, stained with hematoxylin and eosin (H&E) and Brown and Brenn (B&B) and analyzed under an Olympus BX50F4 light microscope. Each series of tooth sections were blind analyzed by one experienced examiner and the data of all morphological features of the pulp tissue were fully recorded.
Secondary outcome measures1. The volume densities or the fractions of pulp volume occupied by the odontoblasts, collagen fibers and fibroblasts, ground substance, blood vessels, inflammatory process and tertiary dentin adjacent to the cavity preparation was performed with the point-counting relative volumetry method using a 100× immersion objective and a Zeiss Kpl 8× eyepiece containing a Zeiss II integration grid (Carl Zeiss GmbH, Jena, Germany) with 100 points in a quadrangular area. In ten sections per tooth, the grid was successively superimposed on 12 histological fields per section at three different pulp levels. The points that were superimposed on each cell or structure (Pi) were counted and the total number of points (Pt) was obtained. Volume density (Vvi) was calculated by the equation: Vvi = Pi/Pt.
2. Remaining dentine thickness (RDT). For each tooth, five histological sections with less RDT were selected. Images of the remaining dentin were captured in a video camera AxioCam HRc (Carl Zeiss MicroImaging GmbH, Göttingen, Germany) coupled to an Axioskop II microscope (Carl Zeiss, Oberköchen, Germany) with 10× objective and analyzed using the AxioVision Release 4.7.2 software (Carl Zeiss Vision Imaging Systems, Oberköchen, Germany). The RDT of each group was the average of the RDT of each specimen.
Overall study start date01/08/2007
Overall study end date01/06/2009

Eligibility

Participant type(s)Patient
Age groupMixed
SexBoth
Target number of participants28 patients (52 teeth)
Participant inclusion criteria1. Sound teeth without signs of cervical lesion
2. Sound teeth without signs of cracks or fractures
3. Sound teeth without signs of periodontal disease
4. Sound teeth without signs of root lacerations
5. Sound teeth with normal response to cold (fast decrease of sensitivity after cold stimuli)
6. Sound teeth without sensitivity to percussion.
7. Patient aged 11-25 years
Participant exclusion criteria1. Teeth with existing caries lesions
2. Teeth with periodontal disease
3. Teeth with cervical lesions
Recruitment start date01/02/2008
Recruitment end date01/12/2008

Locations

Countries of recruitment

  • Brazil

Study participating centre

Bauru Dental School, University of São Paulo.
Al. Dr. Octávio Pinheiro Brisola 9-75. Bauru
Bauru - São Paulo
17012-901
Brazil

Sponsor information

Bauru Dental School, University of São Paulo
University/education

Al. Dr. Octávio Pinheiro Brisola 9-75 Bauru
São Paulo
17012-901
Brazil

Phone +55 (0)14 3235 8000
Email fob@usp.br
Website www.fob.usp.br
ROR logo "ROR" https://ror.org/036rp1748

Funders

Funder type

Government

Coordination for the Improvement of Higher Education Personnel, CAPES. Government of Brazil

No information available

Results and Publications

Intention to publish date01/09/2018
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryStored in repository
Publication and dissemination planPublication in peer reviewed journals

1. 2009 results presented at the International Association of Dental Research https://iadr.abstractarchives.com/abstract/2009miami-118856/histological-evaluation-of-the-human-pulp-response-to-cavity-preparation
2. 2009 results published in Masters thesis (in Portuguese) http://www.teses.usp.br/teses/disponiveis/25/25131/tde-24032010-095844/pt-br.php
IPD sharing plan

Editorial Notes

06/11/2019: Internal review.