IP Indian Journal of Orthodontics and Dentofacial Research

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Online ISSN: 2581-9364

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IP Indian Journal of Orthodontics and Dentofacial Research (IJODR) open access, peer-reviewed quarterly journal publishing since 2015 and is published under the Khyati Education and Research Foundation (KERF), is registered as a non-profit society (under the society registration act, 1860), Government of India with the vision of various accredited vocational courses in healthcare, education, paramedical, yoga, publication, teaching and research activity, with the aim of faster and better more...


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Sarje, Despande, Ashtekar, Gajapurada, Ranjan, Kulshrestha, and Shah: Measurement of inter radicular bone width in different growth patterns for determining safe zone for placement of miniscrew implants – A cone beam computed tomography study


Introduction

One of the most challenging aspects of orthodontic treatment is “Anchorage control”. As described by Archimedes (Greek philosopher), “give me a place to stand and I will move the earth”. He was a pioneer in the field of mathematics and mechanics and presented with anchorage problems much earlier than the clinicians faced it.1 Anchorage has been defined as “the resistance to the forces generated against the active component of an orthodontic appliance”. Simply, it means resistance to displacement. There are two elements of orthodontic appliance. One is the active tooth movement itself and another is the resistance elements.2 Anchorage abides by Newton’s third law which means every action (force) has an equal and opposite reaction. To sum up, all anchorage elements are relative, and all resistance forces are comparative. Various elements that provide orthodontic anchorage include the teeth, hard palate, head, neck, and implants.3

The Temporarily placed Miniscrew for orthodontic anchorage was mentioned for the first time in 1997 by Kanomi followed by the invention of more advanced screw designs.4 Temporary anchorage devices (TADs), like mini-plates, mini-screw, micro-screw, micro-implants were advantageous because of their smaller size that can be placed easily at various implant sites. Also, surgical placement of mini-implants was easy since it does not require full flap retraction and can be loaded immediately. Thus, these were more popular than endosseous implants as a means of anchorage device for orthodontic procedures.5 Though, miniscrews had several advantages yet they had some limitations.

Table 1

Mean ±SD values of all Growth Patterns inPosterior Maxilla

Location

Maxilla

Growth Pattern

3mm

5mm

7mm

9mm

11mm

1st Premolar to

2nd Premolar

(M-D)

Average

1.91200±

.680270

2.17600± .679632

2.37200± .687095

2.60400± .901147

2.96800± 1.057402

Vertical

1.88400±

0.496387

2.12800± 0.555668

2.25600± .740540

2.17200 ± 0.679166

1.95200± .947857

Horizontal

2.67200 ±

.573382

2.86800 ± .739775

3.01200± 1.001382

2.93600 ± 1.432911

2.22800 ± 1.822434

1st Premolar to

2nd Premolar

(B-L)

Average

9.68800±

1.100500

9.62400± 1.114406

9.64400± 1.332629

9.92800± 1.514243

10.44400± 1.858333

Vertical

9.76400 ±

.858235

9.63600± 1.111261

9.35200 ± 1.616869

9.54000± 1.925920

8.52400 ± . 3.702958

Horizontal

9.98000 ±

.925563

9.94800 ± .855434

9.64800 ± 2.238884

8.98400 ± 3.486842

7.49600 ± 5.365436

2nd Premolar

To

1st Molar

(M-D)

Average

1.82400±

.540278

2.05200± .473568

2.31600± .883968

2.40000± 1.565514

1.44000± 1.879716

Vertical

2.37600 ±

.513387

2.58400 ± .709272

2.20000 ± 1.275082

1.73200 ± 1.541568

.77600 ± 1.268621

Horizontal

2.92000 ±

.627163

2.82000 ± 1.170826

2.34800 ± 1.752408

1.69200 ± 2.221471

1.16800 ± 1.942661

2nd Premolar

To

1st Molar

(B-L)

Average

11.08400±

.892412

11.36400± 1.048761

10.93200± 3.485652

9.08800± 5.334192

5.22400± 6.593322

Vertical

11.06000 ±

1.635797

11.36000 ± 1.166905

8.92000 ± 4.663421

6.90800 ± 5.863511

3.72800 ± 5.582750

Horizontal

11.02800 ±

.954603

10.39200 ± 3.294303

7.96000 ± 5.669362

4.94000± 6.224950

3.60800 ± 5.995201

1st

Molar

To

2nd

Molar

(M-D)

Average

1.85600±

1.195854

1.74400± .537804

1.80800± .792107

1.26000± 1.369306

.68800± 1.155898

Vertical

2.27200 ±

.501265

2.13200 ± .412028

1.48800 ± 1.394131

1.01600 ± 1.416769

.37200 ± 1.065176

Horizontal

2.59200 ±

.753282

2.33200 ± .772291

1.87600 ± 1.300410

1.19200 ± 1.298050

.28800 ± .996795

1st

Molar

To

2nd

Molar

(B-L)

Average

13.03200±

1.288319

13.56400± 1.104868

12.76400± 3.995819

7.07600± 6.962057

3.87600± 6.420104

Vertical

13.32400 ±

2.109163

13.66800 ± 2.022935

7.24800 ± 6.746179

4.64000 ± 6.486268

1.84400 ± 5.241428

Horizontal

13.66800 ±

.962081

14.34000 ± 1.126203

11.95200± 6.178263

8.58800 ± 7.816719

1.28000 ± 4.430199

Table 2

Mean ±SD values of all Growth Pattern In theposterior Mandible

Location

Mandible

Growth Pattern

3mm

5mm

7mm

9mm

11mm

1st Premolar to

2nd Premolar

(M-D)

Average

2.12400±

.639844

2.62800± .685881

3.26400± .781494

3.54400± .904655

4.13600± 1.219248

Vertical

2.50400 ±

.836401

3.15200 ± 1.144232

3.45200 ± 1.432399

4.06000 ± 1.946150

4.19200 ± 1.866351

Horizontal

2.76800 ±

.759232

3.23600 ± .860659

3.62000 ± 1.051190

3.90000± 1.156864

4.23200± 1.241545

1st Premolar to

2nd Premolar

(B-L)

Average

9.44800±

1.330764

9.90000± 1.362901

10.38000± 1.379915

10.57600± 1.241061

.10.54400 ± .943433

Vertical

8.04800 ±

.897738

8.13600 ± .791033

8.26000± .505800

8.14800 ± 1.262973

8.62000± 1.119151

Horizontal

8.67600 ±

1.639685

9.46400 ± 1.514618

9.62000 ± 1.430326

9.86800 ± 1.553416

10.04800 ± 1.580643

2nd Premolar

To

1st Molar

(M-D)

Average

2.04800±

.810411

2.27200± .825893

2.71600± 1.066802

3.25600± 1.013279

4.18400± 1.097603

Vertical

2.76400±

.417213

3.15200± 449184

3.36000 ± .512348

3.84400 ±

.797956

4.39600 ± 1.060456

Horizontal

3.12800 ±

.620161

3.34800 ± .641041

3.75600 ± .797956

4.12000 ± .920145

4.52000 ± .901388

2nd Premolar

To

1st Molar

(B-L)

Average

10.29600±

1.084159

10.95600± 1.175472

11.37600± 1.227219

11.67200± 1.031391

11.66000± 1.181454

Vertical

9.60800 ±

.783113

9.92400 ± .800666

9.94800 ± .855921

10.14800 ±

.895414

10.13200 ± .888219

Horizontal

10.38000 ±

1.535144

10.55600 ± 1.228509

10.87200 ± 1.468139

10.93600 ± 1.527492

11.13200 ± 1.654721

1st

Molar

To

2nd

Molar

(M-D)

Average

2.60000±

.763217

2.72800± .948912

3.45600± 1.070078

4.12000± 1.368698

4.76000± 1.594261

Vertical

3.30000 ±

.632456

3.53200 ± .981377

4.11600± 1.266452

4.60400 ± 1.567503

5.08800 ± 1.958171

Horizontal

3.56000 ±

.878446

4.12000 ± 1.084743

4.53600 ± 1.112010

5.08400 ± 1.186620

4.96000 ± 2.008524

1st

Molar

To

2nd

Molar

(B-L)

Average

12.20400±

1.628261

12.97600± 1.336750

13.63600± 1.394895

13.78800± 1.528703

13.14800± 1.212820

Vertical

11.42400 ±

.974372

12.26800 ± 1.236837

12.93200 ± 1.567035

13.04000 ± 1.821172

12.66000 ± 1.952349

Horizontal

11.40400 ±

1.001865

12.65200 ± .855434

13.26400 ± 1.094638

13.89200 ± 1.494969

13.69200 ± 1.653007

Table 3

Comparisonof mean growth pattern at different level of alveolar height among Maxillary 1stpm -2nd Pm in mesio-distal width of vertical growth pattern.

Sum of Squares

df

Mean Square

F

Sig.

Between Groups

2.413

4

.603

1.225

.304

Within Groups

59.118

120

.493

Total

61.532

124

a. AXIS = Vertical, JAW = Maxillary, ORIENTATION = M-D, TEETH = 1st Pm-2nd Pm

Multiple Comparisonsa

Dependent Variable: Growth Pattern In mm

Tukey HSD

(I) AT MM

(J) AT MM

Mean Difference (I-J)

Std. Error

Sig.

95% Confidence Interval

Lower Bound

Upper Bound

3mm

5mm

-.244000

.198525

.734

-.79385

.30585

3mm

7mm

-.372000

.198525

.337

-.92185

.17785

3mm

9mm

-.288000

.198525

.596

-.83785

.26185

3mm

11mm

-.068000

.198525

.997

-.61785

.48185

5mm

7mm

-.128000

.198525

.967

-.67785

.42185

5mm

9mm

-.044000

.198525

.999

-.59385

.50585

5mm

11mm

.176000

.198525

.901

-.37385

.72585

7mm

9mm

.084000

.198525

.993

-.46585

.63385

7mm

11mm

.304000

.198525

.544

-.24585

.85385

9mm

11mm

.220000

.198525

.802

-.32985

.76985

a. AXIS = Vertical, JAW = Maxillary, ORIENTATION = M-D, TEETH = 1st Pm-2nd Pm

Table 4

Comparison of mean growth pattern at different level of alveolar height among Maxillary 2nd Pm and 1st molar- in mesio-distal width of vertical growth pattern.

ANOVAa

Sum of Squares

df

Mean Square

F

Sig.

Between Groups

51.760

4

12.940

10.144

<0.001

Within Groups

153.079

120

1.276

Total

204.839

124

a. AXIS = Vertical, JAW = Maxillary, ORIENTATION = M-D, TEETH = 2nd Pm -1st M

Table 5

Multiple Comparisonsa

Dependent Variable: GROWTH PATTERN IN mm Tukey HSD

(I) AT MM

(J) AT MM

Mean Difference (I-J)

Std. Error

Sig.

95% Confidence Interval

Lower Bound

Upper Bound

3mm

5mm

-.208000

.319457

.966

-1.09280

.67680

3mm

7mm

.176000

.319457

.982

-.70880

1.06080

3mm

9mm

.644000

.319457

.265

-.24080

1.52880

3mm

11mm

1.600000*

.319457

<0.001

.71520

2.48480

5mm

7mm

.384000

.319457

.750

-.50080

1.26880

5mm

9mm

.852000

.319457

.065

-.03280

1.73680

5mm

11mm

1.808000*

.319457

<0.001

.92320

2.69280

7mm

9mm

.468000

.319457

.587

-.41680

1.35280

7mm

11mm

1.424000*

.319457

<0.001

.53920

2.30880

9mm

11mm

.956000*

.319457

.027

.07120

1.84080

*. The mean difference is significant at the 0.05 level.

a. AXIS = Vertical, JAW = Maxillary, ORIENTATION = M-D, TEETH = 2nd Pm -1st M

Table 6

ANOVAa

GRWOTH PATTERN IN mm

Sum of Squares

df

Mean Square

F

Sig.

Between Groups

62.313

4

15.578

14.145

<0.001

Within Groups

132.155

120

1.101

Total

194.468

124

a. AXIS = Vertical, JAW = Maxillary, ORIENTATION = M-D, TEETH = 1st M-2nd M

Table 7

Comparison of mean growth pattern at different level of alveolar height among Maxillary 1st molar and 2nd molar- in mesio-distal width of vertical growth pattern.

Multiple Comparisonsa

Dependent Variable: GRWOTH PATTERN IN mm Tukey HSD

(I) AT MM

(J) AT MM

Mean Difference (I-J)

Std. Error

Sig.

95% Confidence Interval

Lower Bound

Upper Bound

3mm

5mm

.140000

.296822

.990

-.68211

.96211

3mm

7mm

.784000

.296822

.069

-.03811

1.60611

3mm

9mm

1.256000*

.296822

.000

.43389

2.07811

3mm

11mm

1.900000*

.296822

.000

1.07789

2.72211

5mm

7mm

.644000

.296822

.198

-.17811

1.46611

5mm

9mm

1.116000*

.296822

.002

.29389

1.93811

5mm

11mm

1.760000*

.296822

.000

.93789

2.58211

7mm

9mm

.472000

.296822

.507

-.35011

1.29411

7mm

11mm

1.116000*

.296822

.002

.29389

1.93811

9mm

11mm

.644000

.296822

.198

-.17811

1.46611

*. The mean difference is significant at the 0.05 level.

Anchorage through miniscrew was limited by position and angulation of dental roots as well as inter-radicular space.

There were certain recommendations for the safe placement of miniscrews. To preserve periodontal health, a minimum of 1mm alveolar bone is recommended around the miniscrew. Therefore, a total of 3mm or larger inter radicular space is required for safe placement of miniscrew when the diameter of miniscrew and alveolar bone clearance is taken into consideration.6 6 The maxilla was a more suitable site for placement of mini-implants due to its sufficient bone quantity and tooth roots were more widely placed in it. Thus, Maxilla offered a higher success rate.7 Several studies determined the safe site in inter radicular bone for the placement of miniscrews. These sites were called “safe zones”. Moreover, the availability of inter radicular space was different for a different endoskeletal pattern. The inter radicular space was larger in the maxilla in patients with Class II Skeletal pattern as compared to Class III skeletal pattern and vice versa for mandibular jaw. 8 Also, inter-radicular bone availability also depends on gender and age. Studies show that Males and population older than 18 years of age have a larger buccal and lingual cortical bone thickness in both the jaws. 9 To plan miniscrew placement, Panoramic and periapical radiographs were not recommended as they provided two-dimensional images. Computed cone-beam tomography was preferred to obtain volumetric data to plan the mini-screw placement owing to its three-dimensional imaging, low cost, and relatively low radiation dose.10 Thus, our aim of this study was to measure the inter-radicular spaces in the anterior and posterior region on the right side of the maxillary and mandibular jaw and to determine the most reliable sites for miniscrew placement using Cone-beam computed tomography.

Material and Methods

The sample of 75 subjects was selected and divided into 3 groups with 25 subjects in each group. A signed informed consent form was taken in English or Marathi language. Initially, each subject was thoroughly examined clinically according to inclusion and exclusion criteria.

Inclusion criteria

  1. Full complement of erupted teeth excluding the third molars

Exclusion criteria

  1. History of orthodontic or prosthodontic treatment

  2. Dental arches with severe crowding or rotation

  3. Missing teeth, periodontal diseases, and any pathology affecting the jaw will be excluded

  4. Craniofacial deformity

  5. Visually asymmetric jaw

A lateral cephalometric radiograph was taken for all subjects to categorize them in 3 different groups depending upon their relation of the mandibular plane (Go-Gn) to the SN plane according to Steiner analysis. Subjects were categorized into hypodivergent group when mandibular plane measured <28 degrees, average group when the measurement was between 28 degrees to 32 degrees, and hyperdivergent group when the measurement was >32 degrees. Advanced active pixel CMOS sensor, vibration-free motion kodak (8000), the digital radiographic unit was used to take the lateral digital cephalometric radiographs of the subjects involved in the study.

The patients were guided and then instructed to stand in a natural head position (NHP). Calibrated radiographic images were transferred in the software and 8x10” film was obtained and used for determining mandibular plane according to Steiner's analysis. After landmark identification, the SN plane, the mandibular plane, was drawn according to Steiner’s analysis which was the most important step to determine the growth pattern of the patients. After determining the growth pattern of the patients, they were divided into 3 groups according to the measurement of the mandibular plane angle. To avoid any intraobserver error, a single operator performed all the tracings in a standardized manner. The CS9300 (Carestream 9300), CBCT unit of “Carestream Dental” company U.S.A was used to take the Cone Beam Computed Tomography of the subjects involved in the study. The CS 9300 provides more control in limiting radiation exposure to the patients. Pre-treatment Cone Beam Computed Tomography (CBCT) scans were taken with a single 3600 rotational scan time of 20 seconds (Actual exposure time 8 to 9 seconds), with 90KV, 5mA. Assuming subjects to be bilaterally symmetrical, the right-sided jaw of each subject was measured. The Digital Imaging and Communication in Medicine (DICOM) multi-files of each scan were imported into CS 3D imaging software for analysis. Each image was oriented in three planes of place so that morphological analysis of dentoalveolar structures could be done in the Sagittal plane.

A total of 6 interradicular sites were examined in each experimental subject. In the selected patients, the right side of maxillary and mandibular CBCT sectional scan was done using Carestream 9300 machine. Buccolingual width was measured from buccal cortical plate to palatal/lingual cortical plate at 3mm, 5mm, 7mm, 9mm, 11mm, and data were collected in tabulated form. Mesiodistal width measurements from the alveolar crest up to desired bone level were performed.

Results

In vertical growth pattern, in posterior maxilla highest mesiodistal width between 2nd premolar and 1st molar at 7mm. in mandible, it was between 1st and 2nd molar at 11mm. (Table 1, Table 2)

In horizontal growth pattern, in posterior maxilla highest mesiodistal width between 1st and 2nd premolar, and mandible it was between 1st and 2nd molar at 11mm. (Table 3, Table 4 )

In average growth pattern, in posterior maxilla highest mesiodistal width between 2nd premolar and 1st molar and 1st molar at 7mm., in mandible, it was between 1st and 2nd molar at 11mm. (Table 5, Table 6, Table 7)

Discussion

In this study, Interradicular distance between 1st and 2nd premolar, 2nd premolar and 1st molar as well as between 1st and 2nd molar was calculated in both the arches. The Cone beam computer tomography was used in this study. Both mesiodistal, as well as buccolingual distances, were measured. Significance difference between groups was found between the inter radicular bone values of maxillary 2nd premolar and 1st molar region and between 1st and 2nd maxillary molars. Thus, the null hypothesis for this study was rejected. In the posterior maxilla, the greatest amount of mesiodistal inter radicular bone was found between 1st and 2nd premolar at 11mm, 2nd premolar and 1st molar at 9mm,1st molar and 2nd molar at 3mm apically from the alveolar crest. Moreover, the highest buccolingual inter radicular bone was found between 1st and 2nd premolar at 11mm, 2nd premolar and 1st molar at 5mm, and between 1st and 2nd molar at 5 mm. In the posterior mandible, the greatest amount of mesiodistal inter radicular bone was found at 11mm and buccolingually at 9 mm between all the teeth. It can be said that the inter radicular bone is greater apically than towards the alveolar crest. The least amount of bone was between maxillary 1st and 2nd molar (1.8 mm at 3mm depth from alveolar crest) and between mandibular 2nd premolar and molar (2.04 mm at 3mm depth for alveolar crest).

In the study conducted by Poggio, the greatest mesiodistal inter radicular bone was between the 2nd premolar and 1st molar (5.5 mm SD 1.3) at 5mm from the alveolar crest. Lesser mesiodistal space is available on the buccal side than the lingual aspect. Buccopalatally, the greatest amount of inter radicular bone was found between 1st and 2nd molars (14.1 mm SD 1.1) at 5 mm depth from the alveolar crest. Thus, it was concluded that the palatal aspect had more sites for mini-implant placement due to great bone availability.8

Mini implant size varies around 5-6 mm in length and 1-1.2 mm in diameter. Ideally, 1 mm of sound bone is needed to maintain periodontal health. Thus, a minimum of 3.2 mm of inter radicular bone is required for placement of the mini-implant for orthodontic anchorage.11 The insertion site for placement of the mini-implant depends on implant biomechanics as well as the patient’s oral anatomy like the location of maxillary sinus and course of mandibular nerve. 12, 13 Mental foramen lies between 1st and 2nd mandibular premolar.14 Buccal alveolar cortical depth becomes thinner in the posterior region. It is only about 1-1.5 mm at the distal aspect of the 2nd molar. 15 These landmarks must be taken into consideration for safe placement of mini-implant for orthodontic anchorage.

Conclusion

The importance of the relationship between the growth pattern and the availability of inter radicular space may aid the clinician in planning appropriate surgical sites for miniscrew implant placement. This study helps in reducing dilemma about ideal insertion sites for implant placement, as it has given a more definite and accurate finding of insertion sites for implant placement in different growth patterns

Source of Funding

No financial support was received for the work within this manuscript.

Conflicts of Interest

There are no conflicts of interest.

References

1 

K Nayak AM Hegde P Shetty M Jacob Temporary Anchorage Device: An Epitome of Anchorage in Orthodontic TreatmentInt J Clin Pediatr Dent201142143610.5005/jp-journals-10005-1099

2 

I Feldmann L Bondemark Orthodontic Anchorage: A Systemic ReviewAngle Orthodont2006763493501

3 

P Bohara M Kumar H Sharma PK Jayprakash V Misra K Savana Stress distribution and displacement of Maxillary Anterior teeth during en-mass intrusion and extraction: A FEM Study”J Indian Orthod Soc2017511529

4 

B Melsen Mini-implants: Where are we?JCO200539953947

5 

K Singh D Kumar RK Jaiswal A Bansal Temporary anchorage devices -Mini-implantsNatl J Maxillofac Surg20101130410.4103/0975-5950.69160

6 

V Raghavendra Safe Zones for Miniscrews in Orthodontics: A Comprehensive ReviewInt J Dent Med Res2014141358

7 

A Consolaro FL Romano Reasons for mini-implants failure: choosing installation site should be valued!Dent Press J Orthod2014192182410.1590/2176-9451.19.2.018-024.oin

8 

P M Poggio C Incorvati S Velo A Carano Safe zones": a guide for miniscrew positioning in the maxillary and mandibular archAngle Orthod20067621917

9 

P Chaudhari P Bramhe A Bhoosreddy C Bhadage P Rathod D Utekar Influence of age and gender in the assessment of inter-radicular and cortical bone thickness of the anterior maxilla and mandible for the placement of orthodontic mini-implants by cone-beam computed tomography: A retrospective studyJ Int Clin Dent Res Organ 2020121495410.4103/jicdro.jicdro_62_19

10 

R Jacobs B Salmon M Codari B Hassan MM Bornstein Cone beam computed tomography in implant dentistry: recommendations for clinical useBMC Oral Health20181818810.1186/s12903-018-0523-5

11 

AC Gómez EG Núñez EU Querol «Safe» areas with more bone quantity for inter-radicular mini-implant placement in the buccal cortical of the upper maxilla in periodontally compromised patientsRevista Mexicana de Ortodoncia201533e1485310.1016/j.rmo.2016.03.040

12 

P Chaimanee B Suzuki EY Suzuki “Safe Zones” for miniscrew implant placement in different dentoskeletal patternsAngle Orthod201181339740310.2319/061710-111.1

13 

P Echarri L Favero Ortodoncia & microimplantes. Ripano2012

14 

S H Moslemzadeh A Sohrabi A Rafighi Y Kananizadeh A Nourizadeh Evaluation of Interdental Spaces of the Mandibular Posterior Area for Orthodontic Mini-Implants with Cone-Beam Computed TomographyJ Clin Diagn Res2017114ZC09ZC1210.7860/JCDR/2017/25436.9520

15 

A Ono Motoyoshi N Shimizu Cortical bone thickness in the buccal posterior region for orthodontic mini-implantsInt J Oral Maxillofac Surg200837433440



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Article type

Original Article


Article page

137-143


Authors Details

Sagar Sarje, Rahul Despande, Srinivas Ashtekar, Jagadeesh Gajapurada, Alok Ranjan, Rohit Kulshrestha, Krina Shah


Article History

Received : 01-03-2021

Accepted : 22-04-2021

Available online : 12-07-2021


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