Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Contacts Login 
Home Print this page Email this page Users Online: 143



 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2016  |  Volume : 4  |  Issue : 1  |  Page : 1-5

Comparison of mesiodistal measurements of single implant sites on panoramic images generated at different horizontal levels: A cone beam CT study


1 Department of Oral Surgery and Medicine, Public Health and Family Medicine, Jordan University of Science and Technology, Irbid, Jordan
2 Department of Preventive Dentistry, Public Health and Family Medicine, Jordan University of Science and Technology, Irbid, Jordan
3 Department of Community Medicine, Public Health and Family Medicine, Jordan University of Science and Technology, Irbid, Jordan

Date of Web Publication19-Feb-2016

Correspondence Address:
Mustafa Alkhader
Department of Oral Surgery and Medicine, Faculty of Dentistry, Jordan University of Science and Technology, Irbid - 22110
Jordan
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/2321-3841.177052

Rights and Permissions
  Abstract 

Background: This study aimed to compare mesiodistal measurements of single implant sites on cone beam CT (CBCT) panoramic images generated at different horizontal levels. Materials and Methods: CBCT images for 101 single implant sites of 66 patients referred for pre-surgical radiographic dental implant planning were selected for the study. In addition to automatic horizontal level determined by the CBCT software, panoramic images were generated at three different horizontal levels (central incisal edges, crest of the ridge at the implant site, and apices of central incisors) at jaw of interest and mesiodistal measurements were performed by two observers. The measurements were averaged and differences in the means were compared using repeated measures analysis and Bonferroni multiple comparison test. Results: The mean values of mesiodistal measurements at the automatic horizontal level and apices of central incisors level were significantly lower than the mean values at central incisal edges level and crest of the ridge level (8.09, 8.02, 8.54, 8.51 mm respectively). Conclusions: CBCT Panoramic images generated at different horizontal levels can yield different mesiodistal measurements of single implant sites, and further studies with a gold standard need to be conducted to determine the horizontal level of choice.

Keywords: CBCT, dental implant, mesiodistal, panoramic


How to cite this article:
Alkhader M, Hudieb M, Khader Y. Comparison of mesiodistal measurements of single implant sites on panoramic images generated at different horizontal levels: A cone beam CT study. J Oral Maxillofac Radiol 2016;4:1-5

How to cite this URL:
Alkhader M, Hudieb M, Khader Y. Comparison of mesiodistal measurements of single implant sites on panoramic images generated at different horizontal levels: A cone beam CT study. J Oral Maxillofac Radiol [serial online] 2016 [cited 2022 Jan 27];4:1-5. Available from: https://www.joomr.org/text.asp?2016/4/1/1/177052


  Introduction Top


Since the introduction of dental implants into dentistry, the radiographic assessment of implant sites has been required as an essential step in treatment plan which can affect the surgical and prosthodontic steps afterward. Moreover, with the advent of three dimensional imaging modalities, the limitations of two dimensional imaging modalities in evaluating bone quantity (dimensions) and quality, diseases and vital anatomical structures at implant sites could be solved, and the incidence of complications could be decreased. [1]

Biomechanical studies in dental implants field supported by other types of studies [2],[3],[4],[5] have demonstrated the pronounced effect of implant dimensions on the success and survival rates of dental implants. Of the implant dimensions that include implant's length, diameter and abutment connection type, implant diameter has been shown to be the most important factor in the success of dental implants. [6],[7],[8] Implant diameter is governed mostly by the available mesiodistal and buccolingual dimensions of the available alveolar bone ridge. These dimensions can be determined accurately and noninvasively by cone beam computerized tomography (CBCT), [9],[10],[11],[12],[13] which is a low dose CT imaging modality. However, in CBCT, different reconstructed images can be used (coronal, sagittal, axial, oblique and panoramic) and differences in measurements can be anticipated due to several factors. [9],[10],[11],[14],[15],[16],[17],[18],[19],[20],[21],[22]

To generate panoramic images from CBCT, the operator has either to create a dental arch automatically by choosing auto create arch option, or manually by drawing a dental arch on any horizontal level of preference. These options might differ depending on CBCT software being used. It is unknown if panoramic images generated at horizontal levels other than the automatic horizontal level will affect the mesiodistal measurements of single implant sites. Therefore, this study was conducted to determine whether the mesiodistal measurements differ according to the predetermined horizontal level for generating panoramic images or not.


  Materials and Methods Top


Patients

Images for sixty-six patients who underwent CBCT examination for treatment of single implant sites (101 single implant sites) at our dental radiology clinics between January 2011 and January 2013 were retrieved and evaluated. The patients consisted of 31 males and 35 females, with a mean age of 41 years. The exclusion criterion from this study was the presence of artifacts at implant sites, although we did not encounter such cases in this sample size.

CBCT examination

As a CBCT apparatus, KODAK 9500 Cone Beam 3D System (Carestream, Rochester, NY, USA) with flat panel detector was used. The imaging area of CBCT is a cylinder with a height of 15-20.6 cm and a diameter of 9-18 cm, providing isotropic cubic voxels, with sides approximating 0.2 mm-0.3 mm. Maxillofacial areas were examined at a tube voltage of 60-90 kV, a tube current of 10-15 mA, and exposure time of 10-24 seconds.

Examinations were performed by 360 degree rotations in occlusal position, with the patient standing and closing his/her mouth.

Evaluation of images

For generating panoramic images, the curved slicing module was used. In this module an axial image is displayed and can be adjusted to any horizontal level of interest. For arch creation on axial image, there are two options; auto create arch or manual. In case the auto create arch option is used, the software will automatically set several control points (nodes of focal trough) on an axial image generated at a specific horizontal level, which we prefer to call automatic horizontal level. Otherwise, the arch can be created manually by setting several control points on an axial image generated at the desired horizontal level by the operator. Then, the reconstructed panoramic image is displayed with voxel setting at which the volume was acquired, whereby the focal trough can be adjusted to present the reconstructed panoramic image as a traditional panoramic image.

The first panoramic image generated, was at the automatic horizontal level which is displayed automatically when auto create arch function is chosen, then depending on this panoramic image and para-axial images generated, we allocated three different horizontal levels (central incisal edges, crest of the ridge at the implant site, and apices of central incisors) at jaw of interest to generate three different panoramic images. At all the horizontal levels, the arch was created manually, and the position of the control points was in the middle of the displayed arch. To allocate any horizontal level, the yellow indicators on either side of panoramic or para-axial images can be moved up and down to the desired level. Focal trough was set to be 15 mm thickness in all of the generated panoramic images.

Two calibrated observers: One oral radiologist and one oral implantologist with 8 years of experience with CBCT and dental implants were responsible for creating the different panoramic images and measuring the mesiodistal dimensions of implant sites on them [Figure 1], [Figure 2], [Figure 3] and [Figure 4]. Following the example of Mehra and Pai et al., [23] the mesiodistal dimension was the horizontal distance connecting between the highest points located at alveolar crest of nearby teeth.
Figure 1: CBCT based panoramic image generated at automatic horizontal level determined by the software showing the mesiodistal dimension of proposed implant site

Click here to view
Figure 2: CBCT based panoramic image generated at central incisal edges level showing the mesiodistal dimension of proposed implant site at same area

Click here to view
Figure 3: CBCT based panoramic image generated at crest of the ridge level showing the mesiodistal dimension of proposed implant site at same area

Click here to view
Figure 4: CBCT based panoramic image generated at apices of central incisors level showing the mesiodistal dimension of proposed implant site at same area

Click here to view


All images were evaluated on LCD monitor with installed CS 3D imaging viewer (CS 3D imaging viewer, 3.2.9 Carestream, Rochester, NY, USA). When necessary, the window settings were adjusted to optimize the images for evaluation.

Statistical analysis

Intraclass correlation coefficients (ICCs) were calculated to assess inter-observer reliability of mesiodistal measurements at the four horizontal levels (automatic, central incisal edges, crest of the ridge at the implant site, and apices of central incisors) between the first and second observer.

General linear model repeated measure analysis was conducted to test the differences between the mean values of the mesiodistal measurements, then Bonferroni multiple comparison test was used to test the pairwise differences and a P value of less than .05 was considered to be significant.

All previous statistical analyses were done by using a statistical software (SPSS version 16; Chicago, IL, USA).


  Results Top


The distribution of implant sites is shown in [Table 1].
Table 1: Distribution of implant sites in maxilla and mandible

Click here to view


The inter-observer reliability was excellent for mesiodistal measurements on panoramic images generated at the different horizontal levels (automatic level, central incisal edges, crest of the ridge at the implant site, and apices of central incisors); ICCs were: 0.96, 0.95, 0.89, and 0.91 respectively. Given the low interobserver variability, the measurements from the two observers were averaged to obtain mean values. The average mesiodistal measurements (mm) on panoramic images generated at different horizontal levels are shown in [Table 2].
Table 2: The average mesiodistal measurements (mm) on panoramic images generated at different horizontal levels*

Click here to view


Reapeated measurements analysis showed that there were significant differences in the mesiodistal measurements on panoramic images generated at different horizontal levels (F test = 32.6, P < 0.001). Multiple comparisons using Boneferroni test showed that the average mesiodistal measurements at the automatic horizontal level [mean (SD) = 8.09 (2.53) mm] and apices of central incisors level [mean (SD) = 8.02 (2.48) mm] were almost the same (P = 0.664) and not significantly different. Moreover, the average mesiodistal measurements at the central incisal edge level [mean (SD) = 8.54 (2.60) mm] and the crest of the ridge level [mean (SD) = 8.51 (2.56) mm] were almost the same. However, the mean mesiodistal measurements at the automatic horizontal level and apices of central incisors level were significantly lower than those at other horizontal levels.


  Discussion Top


A previous study [14] indicated that the mesiodistal measurements of single implant sites can be done on both panoramic and oblique images generated by CBCT. However, panoramic images were generated at the automatic horizontal level and other horizontal levels were not considered.

We found only one previous study in which CBCT based panoramic images were reconstructed at three different horizontal levels, [24] but only the effect on mesiodistal root angulations was studied and not the mesiodistal dimensions of implant sites.

Comparing CBCT based panoramic images to digital panoramic images, CBCT based panoramic images revealed comparable results in diagnostic image quality. [25],[26] In addition to this, CBCT based panoramic images can produce very accurate measurements of root angulations. [24],[27],[28] Among previous studies, Peck et al. [27] used plaster model measurements as the gold standard for measuring root angulations, and they found that the CBCT based panoramic images revealed very accurate measurements, whereas panoramic images were not accurate.

To generate panoramic images from CBCT data, several parameters need to be considered, like the central plane of focal trough nodes, thickness of focal trough and the horizontal level for arch creation etc. The CBCT software manufacturers guidelines should be followed until international guidelines for creating panoramic images from CBCT data are met. In our case, focal trough nodes were in the centre of the displayed arch. The arch was created at jaw of interest, and the thickness of focal trough was set to be 15 mm according to Kodak software guidelines. However, at the date of writing this study, we could not find guidelines regarding the horizontal level at which we can generate panoramic images manually. On the other hand, there are guidelines for generating panoramic images from conventional CT [29] stating that the horizontal level must be obtained at the level of the teeth roots in the arch of interest.

In our current study, we generated three panoramic images at three different horizontal levels in addition to the one generated at automatic horizontal level, namely: The level of central incisal edges, the crest of the ridge at implant site and the level of apices of central incisors. Despite the small differences in the mean values of mesiodistal measurements, statistically significant differences were shown between measurements at the automatic horizontal level and apices of central incisors level with other levels. This finding could be due to the different shapes of the displayed arches. Although the central plane of focal trough was in the center of the displayed arch at all horizontal levels, positions of the nodes of the focal trough were different according to the shape of the displayed arch, and minimal changes in node position can result in apparent change in mesiodistal dimensions of single implant sites. [14] In addition to this, if the traced centered line is not going though the shortest point between cemento-enamel junction (CEJ) and CEJ of the teeth next to the crestal area of interest, average of voxels buccal and lingual to the traced centered line takes into account a different part of anatomy.

For measuring the mesiodistal dimensions of single implant sites clinically, the caliber should be at the level of the crest. Therefore, we think that panoramic images generated at the level of the crest at implant sites will be the one of choice. However, a study using a gold standard must be conducted to confirm that.


  Conclusions Top


Finally, we can conclude that panoramic images generated by CBCT at different horizontal levels can yield different mesiodistal measurements of single implant sites, and further studies need to be conducted to determine the horizontal level of choice.

Financial support and sponsorship

Nil.

Conflicts of interest

We declare that we have neither financial disclosure nor conflict of interest.

 
  References Top

1.
Jacobs R, Van Steenberghe D. Radiographic Planning and Assessment of Endosseous Oral Implants. 1 st ed. Springer Verlag; Berlin, Heidelberg: 1998.  Back to cited text no. 1
    
2.
Baggi L, Di Girolamo M, Vairo G, Sannino G. Comparative evaluation of osseointegrated dental implants based on platform-switching concept: Influence of diameter, length, thread shape, and in-bone positioning depth on stress-based performance. Comput Math Methods Med 2013;2013:250929.  Back to cited text no. 2
    
3.
Aparicio C, Orozco P. Use of 5-mm-diameter implants: Periotest values related to a clinical and radiographic evaluation. Clin Oral Implants Res 1998;9:398-406.  Back to cited text no. 3
    
4.
Lee JH, Frias V, Lee KW, Wright RF. Effect of implant size and shape on implant success rates: A literature review. J Prosthet Dent 2005;94: 377-81.  Back to cited text no. 4
    
5.
Misch CE. Implant design considerations for the posterior regions of the mouth. Implant Dent 1999;8:376-86.  Back to cited text no. 5
    
6.
Degidi M, Piattelli A, Iezzi G, Carinci F. Wide-diameter implants: Analysis of clinical outcome of 304 fixtures. J Periodontol 2007;78:52-8.  Back to cited text no. 6
    
7.
Pellizzer EP, Verri FR, de Moraes SL, Falcón-Antenucci RM, de Carvalho PS, Noritomi PY. Influence of the implant diameter with different sizes of hexagon: Analysis by 3-dimensional finite element method. J Oral Implantol 2013;39:425-31.   Back to cited text no. 7
    
8.
Duyck J, Naert IE, Van Oosterwyck H, Van der Sloten J, De Cooman M, Lievens S, et al. Biomechanics of oral implants: A review of the literature. Technol Health Care 1997;5:253-73.  Back to cited text no. 8
    
9.
Al-Ekrish AA, Ekram M. A comparative study of the accuracy and reliability of multidetector computed tomography and cone beam computed tomography in the assessment of dental implant site dimensions. Dentomaxillofac Radiol 2011;40:67-75.  Back to cited text no. 9
    
10.
Cremonini CC, Dumas M, Pannuti CM, Neto JB, Cavalcanti MG, Lima LA. Assessment of linear measurements of bone for implant sites in the presence of metallic artefacts using cone beam computed tomography and multislice computed tomography. Int J Oral Maxillofac Surg 2011;40:845-50.  Back to cited text no. 10
    
11.
Dreiseidler T, Neugebauer J, Ritter L, Lingohr T, Rothamel D, Mischkowski RA, et al. Accuracy of a newly developed integrated system for dental implant planning. Clin Oral Implants Res 2009;20:1191-9.  Back to cited text no. 11
    
12.
Suomalainen A, Vehmas T, Kortesniemi M, Robinson S, Peltola J. Accuracy of linear measurements using dental cone beam and conventional multislice computed tomography. Dentomaxillofac Radiol 2008;37:10-7.  Back to cited text no. 12
    
13.
Veyre-Goulet S, Fortin T, Thierry A. Accuracy of linear measurement provided by cone beam computed tomography to assess bone quantity in the posterior maxilla: A human cadaver study. Clin Implant Dent Relat Res 2008;10:226-30.  Back to cited text no. 13
    
14.
Alkhader M, Hudieb M. Comparison of mesiodistal space measurements of single-implant sites on panoramic and oblique images generated by Cone-Beam CT. Surg Radiol Anat 2014;36:255-8.  Back to cited text no. 14
    
15.
Chadwick JW, Lam EW. The effects of slice thickness and interslice interval on reconstructed cone beam computed tomographic images. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;110:e37-42.  Back to cited text no. 15
    
16.
Correa LR, Spin-Neto R, Stavropoulos A, Schropp L, da Silveira HE, Wenzel A. Planning of dental implant size with digital panoramic radiographs, CBCT-generated panoramic images, and CBCT cross-sectional images. Clin Oral Implants Res 2014;25:690-5.  Back to cited text no. 16
    
17.
Ludlow JB, Laster WS, See M, Bailey LJ, Hershey HG. Accuracy of measurements of mandibular anatomy in cone beam computed tomography images. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2007;103:534-42.   Back to cited text no. 17
    
18.
Madrigal C, Ortega R, Meniz C, López-Quiles J. Study of available bone for interforaminal implant treatment using cone-beam computed tomography. Med Oral Patol Oral Cir Bucal 2008;13:307-12.  Back to cited text no. 18
    
19.
Nishikawa K, Suehiro A, Sekine H, Kousuge Y, Wakoh M, Sano T. Is linear distance measured by panoramic radiography reliable? Oral Radiol 2010;26:16-9.  Back to cited text no. 19
    
20.
Pertl L, Gashi-Cenkoglu B, Reichmann J, Jakse N, Pertl C. Preoperative assessment of the mandibular canal in implant surgery: Comparison of rotational panoramic radiography (OPG), computed tomography (CT) and cone beam computed tomography (CBCT) for preoperative assessment in implant surgery. Eur J Oral Implantol 2013;6:73-80.  Back to cited text no. 20
    
21.
Razavi T, Palmer RM, Davies J, Wilson R, Palmer PJ. Accuracy of measuring the cortical bone thickness adjacent to dental implants using cone beam computed tomography. Clin Oral Implants Res 2010;21:718-25.  Back to cited text no. 21
    
22.
Visconti MA, Verner FS, Assis NM, Devito KL. Influence of maxillomandibular positioning in cone beam computed tomography for implant planning. Int J Oral Maxillofac Surg 2013;42:880-6.  Back to cited text no. 22
    
23.
Mehra A, Pai KM. Evaluation of dimensional accuracy of panoramic cross-sectional tomography, its ability to identify the inferior alveolar canal, and its impact on estimation of appropriate implant dimensions in the mandibular posterior region. Clin Implant Dent Relat Res 2012; 14:100-11.   Back to cited text no. 23
    
24.
Van Elslande D, Heo G, Flores-Mir C, Carey J, Major PW. Accuracy of mesiodistal root angulation projected by cone-beam computed tomographic panoramic-like images. Am J Orthod Dentofacial Orthop 2010;137:S94-9.  Back to cited text no. 24
    
25.
Pittayapat P, Galiti D, Huang Y, Dreesen K, Schreurs M, Souza PC, et al. An in vitro comparison of subjective image quality of panoramic views acquired via 2D or 3D imaging. Clin Oral Investig 2013;17:293-300.  Back to cited text no. 25
    
26.
Mischkowski RA, Ritter L, Neugebauer J, Dreiseidler T, Keeve E, Zöller JE. Diagnostic quality of panoramic views obtained by a newly developed digital volume tomography device for maxillofacial imaging. Quintessence Int 2007;38:763-72.  Back to cited text no. 26
    
27.
Peck JL, Sameshima GT, Miller A, Worth P, Hatcher DC. Mesiodistal root angulation using panoramic and cone beam CT. Angle Orthod 2007;77:206-13.  Back to cited text no. 27
    
28.
Mckee IW, Williamson PC, Lam EW, Heo G, Glover KE, Major PW. The accuracy of 4 panoramic units in the projection of mesiodistal tooth angulations. Am J Orthod Dentofacial Orthop 2002;121:166-75; quiz 192.  Back to cited text no. 28
    
29.
Saavedra-Abril JA, Balhen-Martin C, Zaragoza-Velasco K, Kimura-Hayama ET, Saavedra S, Stoopen ME. Dental multisection CT for the placement of oral implants: Technique and applications. Radiographics 2010;30:1975-91.  Back to cited text no. 29
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4]
 
 
    Tables

  [Table 1], [Table 2]


This article has been cited by
1 Custom Focal Trough in Cone-Beam Computed Tomography Reformatted Panoramic Versus Digital Panoramic for Mental Foramen Position to Aid Implant Planning
Khaled Beshtawi,Emad Qirresh,Mohamed Parker,Shoayeb Shaik
Journal of Clinical Imaging Science. 2020; 10: 34
[Pubmed] | [DOI]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Materials and Me...
Results
Discussion
Conclusions
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed3424    
    Printed103    
    Emailed0    
    PDF Downloaded474    
    Comments [Add]    
    Cited by others 1    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]