Effect of Submandibular Fossa on Implant Length in the Posterior Mandibular Region

This retrospective study aims to evaluate the association between submandibular fossa anatomy and implant length in the posterior mandibular region. The study took place from June 1, 2019 to March 1, 2020, during which 295 implants were placed in the posterior mandibular region. Data were reviewed and analyzed from 86,000 patient records that were documented at a private institution. Statistical analysis was performed to assess the association between submandibular fossa anatomy and implant length in the posterior mandibular region. Of the 295 implants, 29.2% were placed in subjects aged 36-45 yr, and 52.9% were male. Of the total population, 52.2% had type P (parallel) submandibular fossa anatomy. The 10-mm implant was the size that was most commonly used (frequency rate, 60.3%). A prevalence of submandibular fossa according to gender showed that 53.8% of males and 50.4% of females had type P (parallel buccal and lingual) plates. A statistically significant difference was found when comparing implant length to different types of submandibular fossa by gender (p < 0.05). And, when association was compared between types of submandibular fossa and implant length, a statistically significant association was found. We conclude that high risk occurs when implants are placed in the mandibular posterior region, because many complications can arise. Proper treatment planning is necessary after complete evaluation using cone-beam computed tomography.