Effects Of Low –Intensity Pulsed Ultrasound on Healing of Mandibular Fractures : An Experimental Study in

RabbitsAuthors- Ozgur Adrogan,

Elmin Essen Yakup Ustin, Mehmet Karku,

Tolga Akova Hakan Uysal

Presented by, Dr. Amit T. SuryawanshiOral and Maxillofacial SurgeonPune, India

Contact details :Email ID - amitsuryawanshi999@gmail.comMobile No - 9405622455

Purpose:

Evaluation of LIPU on healing of fracture mandible on rabbit model by using Mechanical , Radiological and Histological method.

LIPU shown– Ultrasonic sound accelerate the healing process of fractured Long bone

Introduction:

Bone Fracture Healing stages:

Fracture– Hematoma --- Callus formation---Cartilage– Woven bone--- Lamellar bone

Introduction:

Factors Enhance Bone Healing:

Biological Factors; BGF Calcium Sulphate Vit D PTH Estrogen

Other Factors: Electrical + Mechanical + Magnetic + Shock Wave application Hyperboric Oxygen and Non invasive US application

Materials and Methods

32 sk matured rabbitEach 2.8 - 3.2 kgDivided into two groups: Experimental and control

Materials and Methods

Surgical Procedures:

Under GA With all aseptic precaution mandible exposed- one side Osteotomy done 2mm ant to mental foramen with 1.8 mm fissure

bar Repositioned with 4 hole miniplate and screw( leaving 1.8mm gap) Mental nerve secured Wound closed in layer OG intubatin for 5% DA

Materials and Methods

Post Operative care:

Anagesics-Tramadol, im, bd, 4daysAntibitics- Cefaloxine,im,bd,4 daysDiet: Soft Diet for one wk

Materials and Methods

Ultrasound Application: At 2nd post operative day Dose:

1.5 MHz,

200 micro sec burst sine wave

No sedative given during Ultrasonic treatment 20 min sessions repeated daily for 20 days

On 22nd days all the animal were killed and hemisection mandible

collected

Produce 30mw/cm2

Materials and Methods

Radiological assessment:

Digital Radiograph taken and compared with aluminum wedge (thickness .5 to 7 mm) for Radio Densitometric Analysis

Table: Comparison of Bone densities at Fracture zone:

Group No Aluminum Equivalent (mm)(mean)

Control 13 1.339+/- 0.29

LIPU 13 1.635+/-0.379

Materials and Methods

Mechanical Assesment By Universal Testing method Nine hemi mandible from each group selected randomly Mandible placed on lingual side below Failure Load and Load displacement curve obtained

Table: Comparision of the failure load and Stiffness between the groups

Group NO Mean% FailureLoad

Mean% Stiffless

Control 9 71.16+/-18.04 62.89+/- 18.95

LIPU 9 88.93+/-13.60 96.01+/-18.77

Materials and Methods

Histology and Histomorphometry Due to damage of histological structure of the specimen went for mechanical test

have been excluded Histological Parameter on the basis of mineralization amount in the fractured gap

used to asses Grade 1: fibrous unionGrade 2: Predominant fibrous tissues with some cartilageGrade 3: Equal amount of fibrous tissues and cartilageGrade 4: all cartilageGrade 5: Predominantly CartilageGrade 6: Equal amount of cartilage and woven boneGrade 7 : Woven bone with some cartilageGrade9:Some lamellar boneGrade 10: Lamellar bone

Materials and Methods

Histology and HistomorphometryTable: Comparisionof the Histological and histoimorphometric data

Control Group LIPU Group

Histological Grading

6.0 7.11

Bone volume(%) 42.76+/-7.25 72.18+/-.926

Trabecular thickness (mcm)

14.41+/-5.58 24.48+/-6.03

Trabercular Separation (mcm)

18.37+/-5.17 9.10+/-2.81

Mechanism of Action of LIPU

Still controversial It shown that--

1)Increase intracellular calcium in cultured chondrocyte

2)Modulate the adenyle cyclase activity and transform BGF in osteoblast

3)+ mRNA and proteoglycan synthesis by chondrocyte which explain the role on enhancing endochondrial ossification

Result

Boimechanical study tests revealed significant improvent in the mechanical properties of the healing bone in the lipu trated group. This was supported by histological and radiological findings

Conclusion

This Study suggest that LIPU improves the bone healing of Mandibular fracture in rabbits

Thanks