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 - [email protected] 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