Osteotomy speed, heat development, and bone structure influence by various piezoelectric systems-an in vitro study

Efficiency and Heat Production of Ultrasonic Osteotome Strategy in Robot-Assisted Laminectomy

STUDY DESIGN

A biomechanical study.

OBJECTIVE

We aimed to assess temperature fluctuations when applying the ultrasonic osteotome during laminectomy and identify the most appropriate cutting method for robot-assisted laminectomy to mitigate the risk of heat-related injuries.

METHODS

Utilizing a robotic system for laminectomy, the study implemented the ultrasonic bone scalpel to cut both artificial polyurethane bones and animal spinal bones. The research focused on comparing and analyzing the maximum temperature of the inner surface of four types of artificial bones through three different cutting techniques: vertical constant cutting at speeds of .5 mm/s and 1 mm/s, as well as robot-assisted vertical reciprocating cutting. After the initial results, two optimal vertical cutting approaches were selected for subsequent trials, evaluating the effectiveness and temperature impact of various ultrasonic osteotome modes on 10 isolated spinal bones from pigs.

RESULTS

When cutting polyurethane bones, reciprocating cutting demonstrated the lowest maximum temperature in contrast to constant speed cutting at .5 mm/s and 1 mm/s. In the animal bone trial, direct cutting registered an average maximum temperature of 43.25°C with an average cutting duration of 688.3 s, while reciprocating cutting recorded an average maximum temperature of 34.20°C with an average cutting time of 713.0 s.

CONCLUSIONS

The reciprocating cutting strategy utilized in robot-assisted ultrasonic osteotome is effective in reducing heat generation and maintaining high cutting efficiency.

Minimizing Invasiveness in Neurosurgical Osteotomies: A Comparative Histomorphometric Study of Piezoelectric Craniotomy versus High-Speed Drill

BACKGROUND

Piezoelectric bone cutting has gained popularity in neurosurgical osteotomies due to perceived lower trauma compared to rotary instruments. However, histological confirmation of its decreased aggressiveness is lacking, hindering conclusive proof. This study compares the bony and neuro-meningeal invasiveness of piezoelectric craniotomy with high-speed drill techniques.

METHODS

Histological data from 21 sheep undergoing piezoelectric craniotomy and 19 sheep subjected to high-speed electric drill craniotomy were compared. Piezoelectric craniotomy utilized a 0.35 mm micro saw titanium nitride coated. Outcome parameters included the detection of the "smear layer," average osteoblast count per high-power field, and residual bone matrix for bony invasiveness assessment. Parameters for meningeal and brain parenchymal invasiveness included pachymeningeal and leptomeningeal injury, gliosis, and histiocytic infiltration. Statistical significance was determined at P < 0.05.

RESULTS

Results showed the Piezo group had fewer frequent smear layers (P <0.001), higher residual bone matrix (P < 0.05), and greater osteoblast counts per high-power field (P < 0.05). Additionally, the Piezo group exhibited lower rates of leptomeningeal injury, cerebral gliosis, and histiocytic infiltration (P < 0.05).

CONCLUSIONS

Piezoelectric craniotomy preserves residual osteoblast viability and leptomeningeal integrity while demonstrating lower rates of thermally induced gliosis and histiocytic infiltration compared to high-speed drills. This suggests the piezoelectric osteotome's minimal invasiveness in bone, meningeal, and brain tissue.

An overview on the art of piezosurgery in the maxillofacial practice

Introduction: Piezosurgery is an emerging boom in the field of maxillofacial surgery for precise, safe and effective osteotomies sparing the adjacent vital structures compared to conventional surgery. Corpus: It works on the principle of piezoelectric effect in which crystals in the piezoelectric substances get deformed on the application of an electric field. Various studies gave the evidence of improved wound healing and bone formation compared to conventional approaches. The soft tissue sparing capability with improved patient comfort and decreased blood loss gave the utmost importance for this surgical technique in the present as well as future world of surgery. Conclusion: Piezosurgery has emerging as a promising surgical modality with a wide range of clinical applications throughout the whole field of surgery.

Evaluation of temperature and osteotomy speed with piezoelectric system

BACKGROUND

Piezosurgery is an option to realize several clinical and surgical procedures, due to its advantages as precision in osteotomy. This study aims to evaluate the heating and osteotomy speed in bone blocks of ox's shins, to report the best way of its use in the clinical practice.

METHODS

A bone blocks had the dimensions as follow: 20 mm length, 10 mm width, and 5 mm wide. It was evaluated 5 different groups: group LM (low speed and medium pressure); group HM (high speed and medium pressure); group HH (high speed and high pressure); group LH (low speed and high pressure); group LL (low speed and low pressure). The heating increasement was measured with a thermal viewer and the osteotomy was timed when the cut depth reached 5 mm and the whole block detached itself. One-way ANOVA and Tukey tests were adopted to analyze the data and the level of significance was set at a P value of 0.05.

RESULTS

The pressure and speed of the tip, works directly in the generated temperature during osteotomy. The medium pressure level is the most favorable, because high pressure level caused a high increase in heating over the bone and low pressure presented a very long osteotomy time.

CONCLUSIONS

The high speed and medium pressure can be suggested as the most efficient in both standards of time/temperature to realize the osteotomy.

Extraction of impacted third molar with preventive installation of titanium miniplate: Case report

Introduction

Even though is rarely, mandibular fracture after the extraction of third molars can occur in almost 1% of the procedures. Gender, age, position of third molar, tooth volume, bone fragility, systemic disorders, associated lesions, and degree of mandibular atrophy are factors that contribute to increase the incidence of fracture. The installation of the titanium miniplate during exodontia is an important tool to prevent the fracture.

Presentation of case

The objective of this study is to present a clinical case of extraction of inferior impacted third molar, in atrophic mandible, with posterior installation of titanium miniplate, to prevent mandibular fracture.

Discussion and conclusion

preventive installation of titanium miniplate was effective and indeed prevented the mandibular fracture. No trans-operative or immediate post-operative complications were observed. Post-operative follow-up was of three years, with no complications, showing the success of the procedure.

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This study will instruct surgeons on third molar surgery in atrophic mandible.

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It will allow surgeons to avoid mandibular fracture, by installing titanium plate.

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It will ensure the procedure is safe and well conducted for the patients.