Condition category
Oral Health
Date applied
29/08/2018
Date assigned
21/09/2018
Last edited
06/11/2019
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting
Publication status
Results overdue

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

Trial website

Contact information

Type

Scientific

Primary contact

Prof Lourdes Chiok- Ocaña

ORCID ID

http://orcid.org/0000-0002-7760-5281

Contact details

Al. Dr. Octavio Pinheiro Brisola 9-75
São Paulo
17012-901
Brazil
+55 (0)14 3235
lourdeschiok@usp.br

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

145/2007

Study information

Scientific title

Histological evaluation of the human pulp response to different cavity instrumentation and restorative techniques

Acronym

Study hypothesis

1. 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

Bauru Dental School Ethics Committee, 13/12/2007, Protocol number: 145/2007.

Study design

Non-randomised interventional study

Primary study design

Interventional

Secondary study design

Non randomised study

Trial setting

Hospitals

Trial type

Treatment

Patient information sheet

Not available in web format.

Condition

Dental pulp injury following cavity preparation

Intervention

Participants 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 type

Procedure/Surgery

Phase

Drug names

Primary outcome measure

Morphological 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 measures

1. 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 trial start date

01/08/2007

Overall trial end date

01/06/2009

Reason abandoned (if study stopped)

Eligibility

Participant inclusion criteria

1. 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 type

Patient

Age group

Mixed

Gender

Both

Target number of participants

28 patients (52 teeth)

Participant exclusion criteria

1. Teeth with existing caries lesions
2. Teeth with periodontal disease
3. Teeth with cervical lesions

Recruitment start date

01/02/2008

Recruitment end date

01/12/2008

Locations

Countries of recruitment

Brazil

Trial 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

Organisation

Bauru Dental School, University of São Paulo

Sponsor details

Al. Dr. Octávio Pinheiro Brisola 9-75 Bauru
São Paulo
17012-901
Brazil
+55 (0)14 3235 8000
fob@usp.br

Sponsor type

University/education

Website

www.fob.usp.br

Funders

Funder type

Government

Funder name

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

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Publication 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

Intention to publish date

01/09/2018

Participant level data

Stored in repository

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

06/11/2019: Internal review.