Implants placed in an irradiated dog mandible: a morphometric analysis.

Area of Science:

• Oral and Maxillofacial Surgery
• Biomaterials Science
• Radiation Oncology

Background:

• Osseointegration is crucial for oral implant success.
• Radiotherapy can affect bone healing and implant integration.
• Understanding the timing of radiotherapy relative to implantation is vital.

Purpose of the Study:

• To evaluate the influence of radiotherapy timing on oral implant osseointegration.
• To compare bone-implant contact percentages for implants placed before and after radiotherapy.
• To assess the impact of different implant surface coatings on osseointegration post-radiotherapy.

Main Methods:

• A canine model with extracted mandibular teeth was used.
• Implants (hydroxyapatite-coated and titanium plasma spray-coated) were placed.
• Dogs were divided into three groups: control, irradiated post-implantation, and irradiated pre-implantation.
• Radiotherapy involved 4.3 Gy daily for 10 days.
• Bone-implant contact was quantified using scanning electron microscopy after 6 months.

Main Results:

• A statistically significant difference in bone-implant contact was observed between implant types (P < .001).
• Significant differences in osseointegration were found between the three irradiation timing groups (P < .14).
• The highest bone-implant contact percentages were observed for hydroxyapatite-coated implants in the control group (87%).
• Pre-implantation irradiation resulted in the lowest bone-implant contact (28% for titanium plasma spray-coated implants).
• Osseointegration was reduced when radiotherapy occurred before implantation compared to after or no radiation.

Conclusions:

• The timing of radiotherapy significantly influences oral implant osseointegration.
• Osseointegration is achievable both before and after radiotherapy.
• Placing oral implants before radiotherapy exposure appears to yield better bone-implant contact.