Journal of Pharmacy And Bioallied Sciences
Journal of Pharmacy And Bioallied Sciences Login  | Users Online: 2152  Print this pageEmail this pageSmall font sizeDefault font sizeIncrease font size 
    Home | About us | Editorial board | Search | Ahead of print | Current Issue | Past Issues | Instructions | Online submission




 
 Table of Contents  
DENTAL SCIENCE - ORIGINAL ARTICLE
Year : 2014  |  Volume : 6  |  Issue : 5  |  Page : 34-38  

Estimation of soft- and hard-tissue thickness at implant sites


1 Department of Orthodontics, A.J. Institute of Dental Sciences, Mangalore, Karnataka, India
2 Department of Orthodontics, Yenepoya University, Mangalore, Karnataka, India

Date of Submission30-Mar-2014
Date of Decision30-Mar-2014
Date of Acceptance09-Apr-2014
Date of Web Publication25-Jul-2014

Correspondence Address:
Dr. Anil Kumar
Department of Orthodontics, A.J. Institute of Dental Sciences, Mangalore, Karnataka
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0975-7406.137384

Rights and Permissions
   Abstract 

Introduction: Anchorage control is a critical consideration when planning treatment for patients with dental and skeletal malocclusions. To obtain sufficient stability of implants, the thickness of the soft tissue and the cortical-bone in the placement site must be considered; so as to provide an anatomical map in order to assist the clinician in the placement of the implants. Objective: The aim of this study is to evaluate the thickness of soft- and hard-tissue. Materials and Methods: To measure soft tissue and cortical-bone thicknesses, 12 maxillary cross-sectional specimens were obtained from the cadavers, which were made at three maxillary mid-palatal suture areas: The interdental area between the first and second premolars (Group 1), the second premolar and the first molar (Group 2), and the first and second molars (Group 3). Sectioned samples along with reference rulers were digitally scanned. Scanned images were calibrated and measurements were made with image-analysis software. We measured the thickness of soft and hard-tissues at five sectional areas parallel to the buccopalatal cementoenamel junction (CEJ) line at 2-mm intervals and also thickness of soft tissue at the six landmarks including the incisive papilla (IP) on the palate. The line perpendicular to the occlusal plane was made and measurement was taken at 4-mm intervals from the closest five points to IP. Results: (1) Group 1:6 mm from CEJ in buccal side and 2 mm from CEJ in palatal side. (2) Group 2:8 mm from CEJ in buccal side and 4 mm from CEJ in palatal side. (3) Group 3:8 mm from CEJ in buccal side and 8 mm from CEJ in palatal side. Conclusions: The best site for placement of implant is with thinnest soft tissue and thickest hard tissue, which is in the middle from CEJ in buccal side and closest from CEJ in palatal side in Group 1 and faraway from CEJ in buccal side and closest from CEJ in palatal side in Group 2 and faraway from CEJ in buccal side and faraway from CEJ in palatal side in Group 3.

Keywords: Anchorage, hard tissue, implant stability, soft tissue


How to cite this article:
Kumar A, Mascarenhas R, Husain A. Estimation of soft- and hard-tissue thickness at implant sites. J Pharm Bioall Sci 2014;6, Suppl S1:34-8

How to cite this URL:
Kumar A, Mascarenhas R, Husain A. Estimation of soft- and hard-tissue thickness at implant sites. J Pharm Bioall Sci [serial online] 2014 [cited 2019 Nov 12];6, Suppl S1:34-8. Available from: http://www.jpbsonline.org/text.asp?2014/6/5/34/137384

Anchorage control is a critical consideration when planning treatment for patients with dental and skeletal malocclusions. The use of endosseous implants for absolute orthodontic anchorage has been the focus of many studies. Gainsforth and Higley, [1] placed vitallium screws in the jaw bones of dogs in 1945. Roberts et al., [2] used titanium screws as orthodontic implants in dog mandibles. Turley et al., [3] Shapiro and Kokich, [4] and Schweizer et al., [5] in their study have reported the use of endosseous implants in orthodontics, and Block and Hoffman, [6] used onplants. When skeletal anchorage is stable, biocompatible, and free from site specificity, it can be used effectively without patient compliance. Several systems such as miniplates, miniscrews, and microscrews can satisfy these criteria, which can be placed in different positions: the inferior ridge of the piriform aperture, the maxillary alveolar bone, the infrazygomatic crest, the palatal alveolar bone, the maxillary tuberosity, the hard palate, and the mid-palatal suture area.

Potential complications with miniscrews in orthodontics are soft tissue irritation at the site of insertion, risk of infection, and premature loosening of the screw. The stability of implant increases with the quality of the bone.

For this reason, it is very important to know the thickness of soft and hard-tissue at implant placement sites. Several studies have been conducted on the sites of implant placement using different methods.

In this study, buccopalatal cross-sectional samples from interdental areas of the posterior teeth and mid-palatal suture areas of cadavers were evaluated. This information will assist the clinician in placement of orthodontic implants.


   Materials and Methods Top


To measure the soft and hard-tissue thickness of the areas mostly interested by miniscrews insertion, such as buccopalatal interdental bone and maxillary mid-palatal suture, 12 cadavers were selected with all maxillary premolars and molars still intact. To measure the incisal areas, 12 cadavers with intact maxillary occlusal planes (at least incisors and first molars remaining) were selected. Cross-sectional specimens were made at three areas: The interdental area between the first and second premolars (Group 1), the interdental area between the second premolar and the first molar (Group 2), and the interdental area between the first and second molars (Group 3). The thickness of soft and hard-tissues were measured at five sectional areas parallel to the buccopalatal cementoenamel junction (CEJ) line at 2 mm intervals [Figure 1] for each group.
Figure 1: Measurement of the thickness of the soft- and hard-tissues on the buccal side and palatal side of the sectioned specimen on parallel lines drawn 2, 4, 6, 8, and 10 mm, from cementoenamel junction

Click here to view


  1. Outer point of the buccal side of the sectioned specimen on a parallel line drawn 2 mm superior to the CEJ line
  2. Outer point of the buccal side of the sectioned specimen on a parallel line drawn 4 mm superior to the CEJ line
  3. Outer point of the buccal side of the sectioned specimen on a parallel line drawn 6 mm superior to the CEJ line
  4. Outer point of the buccal side of the sectioned specimen on a parallel line drawn 8 mm superior to the CEJ line
  5. Outer point of the buccal side of the sectioned specimen on a parallel line drawn 10 mm superior to the CEJ line
  6. Outer point of the palatal side of the sectioned specimen on a parallel line drawn 2 mm superior to the CEJ line
  7. Outer point of the palatal side of the sectioned specimen on a parallel line drawn 4 mm superior to the CEJ line
  8. Outer point of the palatal side of the sectioned specimen on a parallel line drawn 6 mm superior to the CEJ line
  9. Outer point of the palatal side of the sectioned specimen on a parallel line drawn 8 mm superior to the CEJ line
  10. Outer point of the palatal side of the sectioned specimen on a parallel line drawn 10 mm superior to the CEJ line.


The thickness of soft tissue were also measured at 6 landmarks mentioned below, including the incisive papilla (IP) on the palate, which meet with the line perpendicular to the occlusal plane and passing through closest five points from the IP at 4-mm intervals [Figure 2].
Figure 2: Measurement of the thickness of the soft tissue at six points on the palate of the sectioned specimen, which were drawn at 4-mm intervals from the incisive papilla and perpendicular to the occlusal plane

Click here to view


  1. Outer point of the sectioned specimen at the IP of the palate
  2. Outer point of the sectioned specimen contacted with a parallel line drawn 4 mm posterior to the line passing through IP perpendicular to the occlusal plane
  3. Outer point of the sectioned specimen contacted with a parallel line drawn 8 mm posterior to the line passing through IP perpendicular to the occlusal plane
  4. Outer point of the sectioned specimen contacted with a parallel line drawn 12 mm posterior to the line passing through IP perpendicular to the occlusal plane
  5. Outer point of the sectioned specimen contacted with a parallel line drawn 16 mm posterior to the line passing through IP perpendicular to the occlusal plane
  6. Outer point of the sectioned specimen contacted with a parallel line drawn 20 mm posterior to the line passing through IP perpendicular to the occlusal plane.


The specimens were sectioned with a jewelers saw. Sectioned samples along with reference rulers were digitally scanned (Umax flatbed scanner [UMAX. 48 Bit True Color Depth]). Scanned images were calibrated and measurements were made with image-analysis software (Autocad 2004 [Autocad is the Industry Software that Sets the Standard in Cad Design.).


   Results Top


Group 1

The buccal soft tissue is thickest at 10 mm (1.73742) and thinnest at 4 mm (1.50317) from the CEJ

  • The palatal soft tissue is thickest at 8 mm (3.14033) and thinnest at 2 mm (2.44308) from the CEJ
  • The buccal hard tissue is thickest at 10 mm (1.43733) and thinnest at 2 mm (1.25350) from the CEJ
  • The palatal hard tissue is thickest at 2 mm (1.55575) and thinnest at 10 mm (1.36567) from the CEJ.


Buccal side

  • The hard tissue is thickest at 10 mm (1.43733) and soft tissue at 10 mm (1.73742) from the CEJ
  • The soft tissue is the thinnest at 4 mm (1.50317) and hard tissue at 4 mm (1.28233) from the CEJ
  • Average thickness of soft tissue at 6 mm is (1.62042) and hard tissue at 6 mm is (1.39650) from CEJ.


Palatal side

  • The hard tissue is thickest at 2 mm (1.55575) and soft tissue at 2 mm (2.44308) from the CEJ
  • The soft tissue is the thinnest at 2 mm (2.44308) and hard tissue at 2 mm (1.55575) from the CEJ
  • Average thickness of soft tissue at 6 mm is (3.00008) and hard tissue at 6 mm is (1.47767) from CEJ [Table 1].
    Table 1: Comparison of measurements (in mm) of sectioned specimens in Group 1


    Click here to view


Group 2

  • The buccal soft tissue is thickest at 10 mm (2.04292) and thinnest at 4 mm (1.85242) from the CEJ
  • The palatal soft tissue is thickest at 10 mm (3.37350) and thinnest at 2 mm (2.75925) from the CEJ
  • The buccal hard tissue is thickest at 8 mm (1.58342) and thinnest at 6 mm (1.49608) from the CEJ
  • The palatal hard tissue is thickest at 4 mm (1.70542) and thinnest at 2 mm (1.53958) from the CEJ.


Buccal side

  • The hard tissue is thickest at 8 mm (1.58342) and soft tissue at 8 mm (1.86558) from the CEJ
  • The soft tissue is the thinnest at 4 mm (1.85242) and hard tissue at 4 mm (1.54075) from the CEJ
  • Average thickness of soft tissue at 6 mm is (1.96000) and hard tissue at 2 mm is (1.51608) from CEJ.


Palatal side

  • The hard tissue is thickest at 4 mm (1.70542) and soft tissue at 4 mm (2.84675) from the CEJ
  • The soft tissue is thinnest at 2 mm (2.75925) and hard tissue at 2 mm (1.53958) from the CEJ
  • Average thickness of soft tissue at 6 mm is (3.12100) and hard tissue at 6 mm is (1.67742) from CEJ [Table 2].
    Table 2: Comparison of measurements (in mm) of sectioned specimens in Group 2


    Click here to view


Group 3

  • The buccal soft tissue is thickest at 2 mm (2.0055) and thinnest at 6 mm (1.5177) from the CEJ
  • The palatal soft tissue is thickest at 10 mm (3.05708) and thinnest at 6 mm (2.48025) from the CEJ
  • The buccal hard tissue is thickest at 8 mm (1.61108) and thinnest at 2 mm (1.53433) from the CEJ
  • The palatal hard tissue is thickest at 2 mm (1.5494) and thinnest at 6 mm (1.3058) from the CEJ.


Buccal side

  • The hard tissue is thickest at 8 mm (1.61108) and soft tissue at 8 mm (1.6779) from the CEJ
  • The soft tissue is the thinnest at 6 mm (1.5177) and hard tissue at 6 mm (1.54778) from the CEJ
  • Average thickness of soft tissue at 4 mm is (1.7431) and hard tissue at 6 mm is (1.54778) from the CEJ [Table 3].
    Table 3: Comparison of measurements (in mm) of sectioned specimens in Group 3


    Click here to view


Palatal side

  • The hard tissue is thickest at 2 mm (1.5494) and soft tissue at 2 mm (2.69117) from the CEJ
  • The soft tissue is thinnest at 6 mm (2.48025) and hard tissue at 6 mm (1.3058) from the CEJ
  • Average thickness of soft tissue at 8 mm is (2.66167) and hard tissue at 10 mm is (1.4190) from CEJ. Measurement of thickness of soft tissue at 6 landmarks (on the IP and at 4-mm intervals from the IP) showed that the soft tissue is thickest at 12 mm (1.92079) and thinnest at 20 mm (1.65256) from IP [Table 4].
    Table 4: Measurements (in mm) in sectioned specimens at mid-palatal suture area


    Click here to view



   Discussion Top


Orthodontic anchorage is the ability to limit the movement of some teeth while achieving the desired movement of other teeth. For this reason, orthodontists have been searching for the most appropriate methods and appliances to achieve this goal. The age old problem in orthodontics is essentially the application of Newton's third law of motion: for every action, there is an equal and opposite reaction. Orthodontists often have inadequate mechanical systems with which to control anchorage, which leads to a loss of anchorage in the reactive unit and thus incomplete correction of intra- and inter-arch alignment problems. Moreover, in an attempt to overcome these limitations, clinicians often incorporate bulky acrylic appliances or extraoral appliances, which when combined with the ever challenging problem of uncooperative patients, are often a futile attempt at best. Hence, to overcome these problems microimplants had been introduced. The stability of these microimplants depends on the placement site, thickness of the bone and soft tissue. Thinnest soft tissue and thickest bone area is ideal for implant placement. Different methods have been used to measure the thickness.

Poggio et al., [7] conducted a study using the volumetric tomographic images of 25 maxillae and 25 mandibles taken with the NewTom System T (Newtom is a Radiographic Methoid Used in Other Study by a Different Authors Mentioned in my Reference). In the maxilla, the greatest amount of mesiodistal bone was on the palatal side between the second premolar and the first molar. The lowest amount of bone was in the tuberosity. The greatest thickness of bone in the buccopalatal dimension was between the first and second molars, whereas the lowest was found in the tuberosity. Schnelle et al., [8] conducted a study using panoramic radiographs. Bone stock for placement of screws was found to exist primarily in the maxillary (mesial to first molars) and mandibular (mesial and distal to first molars) posterior regions. Typically, adequate bone was located more than halfway down the root length, which is likely to be covered by movable mucosa. King et al., [9] conducted a study using Cone beam computed tomographic scans. Vertical bone depth was measured at nine unilateral locations in the PP of each subject. They found a significant variability in the bone thickness among locations and among subjects. Male subjects had significantly greater mean bone thickness in six of the nine locations measured, showing a mean of 1.22 mm more vertical bone than females showed at these locations. Costa et al., [10] conducted a study using volumetric computed tomography for bone depth and needle with a rubber stop for mucosal depth. The results indicate that bone thickness will allow temporary anchorage devices (TADs) 10 mm in length only in the symphysis, retromolar, and palatal premaxillary regions. TADs 6-8 mm in length can be placed in the incisive fossa, in the upper and lower canine fossae. A direct study was conducted by Kim et al., [11] using cadavers. Their results indicated that in all groups, buccal soft tissues were thickest closest to and far away from the CEJ and thinnest in the middle. Palatal soft tissue thickness increased gradually from the CEJ toward the apical region in all groups. Buccal cortical-bone was thickest closest and far away from the CEJ and thinnest in the middle in Groups 1 and 2. In Group 3, unlike Groups 1 and 2, thickness was greatest at the middle. Palatal cortical-bone thickness was greatest 6 mm apical to the CEJ in Groups 1 and 3, and 2 mm apical to the CEJ in Group 2. Along the mid-palatal suture, palatal mucosa remained uniformly 1 mm thick posterior to the IP. However, in our study, we found different findings with regard to hard- and soft-tissue thickness at the various sites, and these differences may be attributed to racial differences between the two populations.

According to our study, the best site for placement of implant considering the thinnest soft tissue and thickest hard tissue is

  • Group 1: 6 mm from CEJ in buccal side and 2 mm from CEJ in palatal side
  • Group 2: 8 mm from CEJ in buccal side and 4 mm from CEJ in palatal side
  • Group 3: 8 mm from CEJ in buccal side and 8 mm from CEJ in palatal side.



   Conclusion Top


Implant passes through the soft tissue and bone, and therefore the thickness of the soft tissue and cortical-bone at the surgical site are critical factors for success of the implant.

In terms of soft- and hard-tissues, thin soft tissue is more advantageous because the likelihood of inflammation is lower. The stability of miniscrew implants depends on the quality and quantity of the cortical-bone. The main objective of an orthodontic screw is to gain maximum retention by placing the screw in an area with the thinnest soft tissue and the thickest cortical-bone. Surgical placement of miniscrew implants for orthodontic anchorage in the maxillary molar region requires consideration of the placement site and angle based on anatomical characteristics. The best site for placement of implant is with thinnest soft tissue and thickest hard tissue, which is in the middle from CEJ in buccal side and closest from CEJ in palatal side in Group 1 and faraway from CEJ in buccal side and closest from CEJ in palatal side in Group 2 and faraway from CEJ in buccal side and faraway from CEJ in palatal side in Group 3.

 
   References Top

1.Gainsforth BL, Higley LB. A study of orthodontic anchorage possibilities in basal bone. Am J Orthod Oral Surg 1945;31:406-16.  Back to cited text no. 1
    
2.Roberts WE, Helm FR, Marshall KJ, Gongloff RK. Rigid endosseous implants for orthodontic and orthopedic anchorage. Angle Orthod 1989;59:247-56.  Back to cited text no. 2
    
3.Turley PK, Kean C, Schur J, Stefanac J, Gray J, Hennes J, et al. Orthodontic force application to titanium endosseous implants. Angle Orthod 1988;58:151-62.  Back to cited text no. 3
    
4.Shapiro PA, Kokich VG. Uses of implants in orthodontics. Dent Clin North Am 1988;32:539-50.  Back to cited text no. 4
    
5.Schweizer CM, Schlegel KA, Rudzki-Janson I. Endosseous dental implants in orthodontic therapy. Int Dent J 1996;46:61-8.  Back to cited text no. 5
    
6.Block MS, Hoffman DR. A new device for absolute anchorage for orthodontics. Am J Orthod Dentofacial Orthop 1995;107:251-8.  Back to cited text no. 6
    
7.Poggio PM, Incorvati C, Velo S, Carano A. "Safe zones": A guide for miniscrew positioning in the maxillary and mandibular arch. Angle Orthod 2006;76:191-7.  Back to cited text no. 7
    
8.Schnelle MA, Beck FM, Jaynes RM, Huja SS. A radiographic evaluation of the availability of bone for placement of miniscrews. Angle Orthod 2004;74:832-7.  Back to cited text no. 8
    
9.King KS, Lam EW, Faulkner MG, Heo G, Major PW. Predictive factors of vertical bone depth in the paramedian palate of adolescents. Angle Orthod 2006;76:745-51.  Back to cited text no. 9
    
10.Costa A, Pasta G, Bergamaschi G. Intraoral hard and soft-tissue depths for temporary anchorage devices. Semin Orthod 2005;11:10-5.  Back to cited text no. 10
    
11. Kim H, Yun H, Park H, Kim D, Park Y. Soft-tissue and cortical bone thickness at orthodontic implant sites. Am J Orthod Dentofacial Orthop 2006;130:177-82.  Back to cited text no. 11
    


    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

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
    Materials and Me...
   Results
   Discussion
   Conclusion
    References
    Article Figures
    Article Tables

 Article Access Statistics
    Viewed1262    
    Printed53    
    Emailed0    
    PDF Downloaded58    
    Comments [Add]    

Recommend this journal