Fig. 3. One possible missing category (depicted as “X”) would be a bone type with thick cortical layer and sparse trabecular bone, which would have intermediate characteristics and behavior between the types with thick (2) or thin (3) cortical bones
Fig. 3. One possible missing category (depicted as “X”) would be a bone type with thick cortical layer and sparse trabecular bone, which ...
Fig. 2. Preoperative CT image showing the site for the definition of the ROI (simulated area delimited by a yellow dashed line for illustration purpose) in the axial (a), coronal (b), and sagittal (6 × 6 mm) (c) sections
Fig. 2. Preoperative CT image showing the site for the definition of the ROI (simulated area delimited by a yellow dashed line for illustration purpose) in the axial (...
Fig. 1. Clinical case of a short implant (4.1 × 6 mm) placed in the region of the left maxillary first molar. a Implant installed. b Insertion torque measurement using the manual torque wrench. c Implant with healing cap and flap suture. d Immediate periapical radiograph after surgery
Fig. 1. Clinical case of a short implant (4.1 × 6 mm) placed in the region of the left maxillar...
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Std error
95% confidence interval
P value (F; DF)
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Torque
Tactile
CT visual
MGV_avg
MGV_axial
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95% confidence interval
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Triches, D.F., Alonso, F.R., Mezzomo, L.A. et al. Relation between insertion torque and tactile, visual, and rescaled gray value measures of bone quality: a cross-sectional clinical study with short implants.
Int J Implant Dent 5, 9 (2019). https://doi.org/10.1186/s40729-019-0158-6
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Received: 07 October 2018
Accepted: 06 January 2019
Published: 11 February...
Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were m...
This study was conducted in accordance with the tenets of the Declaration of Helsinki, and all procedures involving human subjects were approved by the ethics committee of the Pontifical Catholic University of Rio Grande do Sul/UBEA (ethical approval letter OF.CEP-772/10; research protocol CEP 10/05074).
Written informed consent was obtained from all study participants.
Diego Fernandes Triches, ...
All authors (1) made substantial contributions to the conception and/or design of the work or the acquisition, analysis, or interpretation of data for the work; (2) drafted the paper or revised it critically; (3) approved the final version of this manuscript; and (4) agreed to be accountable for all aspects of the work. Categories of authors’ contribution are as follows: concept/design (RSS, DFT...
Postgraduate Program in Dentistry, Pontifical Catholic University of Rio Grande do Sul (PUCRS), Dental School, Avenida Ipiranga, 6681 – Prédio 6, Porto Alegre, RS, 90619-900, Brazil
Diego Fernandes Triches, Fernando Rizzo Alonso, Danilo Renato Schneider, Eduardo Aydos Villarinho, Maria Ivete Rockenbach, Eduardo Rolim Teixeira & Rosemary Sadami Shinkai
Postgraduate Program in Dentistry,...
The authors would like to thank Professor Helena de Oliveira and Dr. Geisa Medeiros for their early assistance with CT software.
The work was supported by a research grant from Coordination for the Improvement of Higher Education Personnel (CAPES, Brazil; PNPD grant), the National Counsel of Technological and Scientific Development (CNPq, Brazil; Universal grant), and the International Team for I...
Kaya S, Yavuz I, Uysal I, Akkus Z. Measuring bone density in healing periapical lesions by using cone beam computed tomography: a clinical investigation. J Endod. 2012;38:28–31.
Brosh T, Yekaterina BE, Pilo R, Shpack N, Geron S. Can cone beam CT predict the hardness of interradicular cortical bone? Head Face Med. 2014;10:12.
Tatli U, Salimov F, Kürkcü M, Akoğlan M, Kurtoğlu C. Does cone be...
Nomura Y, Watanabe H, Honda E, Kurabayashi T. Reliability of voxel values from cone-beam computed tomography for dental use in evaluating bone mineral density. Clin Oral Implants Res. 2010;21:558–62.
Reeves TE, Mah P, McDavid WD. Deriving Hounsfield units using gray levels in cone beam CT: a clinical application. Dentomaxillofac Radiol. 2012;41:500–8.
Cassetta M, Stefanelli LV, Pacifici A, P...
Degidi M, Daprile G, Piattelli A. Determination of primary stability: a comparison of the surgeon’s perception and objective measurements. Int J Oral Maxillofac Implants. 2010;25:558–61.
Alonso FR, Triches DF, Mezzomo LAM, Teixeira ER, Shinkai RSA. Primary and secondary stability of single short implants. J Craniofac Surg. 2018. https://doi.org/10.1097/SCS.0000000000004567.
Ribeiro-Rotta RF,...
Cone beam computed tomography
Computed tomographic
Digital Imaging and Communications in Medicine
Field of view
Mean gray values
Region of interest
In summary, within the conditions and limitations of this study, the results suggest that bone quality has a significant effect on the primary stability of short implants as measured by insertion torque. Insertion torque had significant correlation with all assessment methods of bone quality. For preoperative CT evaluation of bone quality, mean gray values (optical density) had stronger associatio...
The present study also used the same preoperative CT images for visual evaluation of bone quality at the exact implant site, using the axial, coronal, and sagittal sections in a standardized procedure. There was a fairly moderate correlation between CT visual assessment and mean gray values, but no statistical difference was found in average mean gray values between the visual classification of bo...
In this study, low- and medium-density values (air and a central FOV soft tissue) were used as reference calibration points for image normalization. The use of a reference object in the FOV containing at least two materials of known density could allow for a calibration similar to the use of reference phantoms in quantitative CT, rather than the “standard” automatic normalization function avai...
This study showed that low bone quality, as assessed by clinical and image methods, is related with low primary stability of 6-mm short implants placed at the posterior region of the maxilla and mandible. Higher insertion torque values were associated with better bone types and higher mean gray values in CT images. Insertion torque had a negative moderate association with bone type categorization ...
Descriptive statistics of the sample are shown in Table 1. For statistical analysis, some data were missing: one implant had mobility after surgery and was lost and four CT scans, containing 11 ROIs, were not used for bone quality analysis due to technical problems. As only one case was categorized as bone type 1 by CT visual or by tactile evaluation, the corresponding mean gray values were exclu...
The mean gray value of each rescaled ROI was measured on the three orthogonal planes: axial, coronal, and sagittal, totaling three ROIs per implant site. The average of the rescaled gray values for the three ROIs was computed for each implant site.
Data were analyzed by descriptive and inferential statistics using the software XLSTAT version 2018 (Addinsoft SARL, New York, USA), and a two-tailed ...
Axial ROI: Using the reference implant location line, the ROI was defined as the alveolar bone area with a 6-mm width corresponding to 3 mm on each side of the future implant center, including the buccal and lingual cortical layers.
Coronal ROI: Area defined by the outer border of the cortical bone with a 6-mm height and a line joining the buccal and lingual cortical layers.
Sagittal ROI: A 6...
The insertion torque was measured using the manual torque wrench (Straumann Dental Implant System®, Waldenburg, Switzerland) (Fig. 1b), according to three categories: 35 N cm. A healing cap was installed, and the suture was made with nylon 5-0 (Fig. 1c). The patients were prescribed with antibiotics (amoxicillin 500 mg, 8/8 h for 7 days), anti-inflammatory drugs (nimesulide 100 mg,...
This study reports cross-sectional, correlational data of a prospective clinical research project [2] approved by the university Institutional Review Board (10/05074). The research protocol followed the precepts of the Declaration of Helsinki and its amendments. All patients signed an informed consent form.
A consecutive, non-probabilistic sample consisted of 45 implants placed in 20 patients tre...
Both multislice CT and cone beam CT are used for presurgical assessment of bone density and quality [4,5,6,7,8,9,10,11]. There is a strong correlation between gray values in cone beam CT and Hounsfield units in multislice CT [4, 12,13,14]. The visual inspection of CT sections avoids the superimposition of anatomical structures seen in radiographs; thus, the region of interest in trabecular bone ca...
The early clinical success of short implants can be affected by poor bone quality and low primary stability because implant micromovement can promote the formation of a fibrous capsule during the osseointegration process. It has been reported that the greater the insertion torque, the greater the resistance of the bone-implant interface to the shear forces that tend to rotate the implant [1]. Clin...
This study assessed the relationship between insertion torque and bone quality evaluated during surgery and in preoperative computed tomographic (CT) images analyzed either visually or by rescaled mean gray values (MGVs). The study also tested the correlation between the clinical and radiographic measures of bone quality.
The consecutive sample was composed of 45 short implants (4.1 × 6 mm...