Correlation Between Mandibular Cortical Index and Primary Implant Stability

Area of Science:

• Dentistry
• Orthodontics
• Radiology

Background:

• Initial stability is crucial for dental implant success.
• Osteoporosis poses risks to implant treatment prognosis, especially in elderly patients.
• The mandibular cortical index (MCI) and implant stability quotient (ISQ) are key metrics for assessing bone quality and implant stability.

Purpose of the Study:

• To statistically evaluate the relationship between the mandibular cortical index (MCI) and implant stability quotient (ISQ).
• To assess the impact of mandibular bone quality on dental implant stability in a Japanese patient cohort.

Main Methods:

• Retrospective analysis of 79 patients (190 implants) at Nihon University School of Dentistry Dental Hospital.
• Data collected included patient demographics, systemic diseases, implant details, ISQ measurements, and MCI classification from digital panoramic radiography.
• Statistical analysis using Spearman's rank correlation and one-way ANOVA was performed.

Main Results:

• A weak negative correlation was found between MCI Class III and ISQ values (p < 0.01).
• The mean ISQ value for MCI Class III implants (67.2 ± 11.2) was significantly lower than for Class I (72.8 ± 10.4) and Class II (73.2 ± 10.4) implants (P < 0.01).
• No significant correlation was observed between age at implant placement and ISQ values (p > 0.05).

Conclusions:

• MCI Class III reflects mandibular bone demineralization and is associated with reduced implant stability.
• Preoperative MCI assessment is valuable for predicting bone quality deterioration, particularly in elderly patients or those at risk for osteoporosis.
• MCI evaluation can guide treatment decisions, including implant size, insertion torque, and the need for bone grafting.