# Predicting the Failure of Dental Implants Using Supervised Learning Techniques
## 4 Discussion
* Chewing betel nut and alcohol consumption  
According to the conclusion of the 17 th European Association of Osseeointegration Congress in 2008, poor oral hygiene and lifestyle are high risk factors for peri-implantitis, and betel nut chewing and alcohol consumption are the detrimental life habits commonly seen among Taiwanese [25]. A literature review by a Hong Kong research team revealed that betel nut or tobacco chewing, like smoking, can lead to oral cancer, periodontal disease, or even dental implant failure [26]. According to [PERSON] et al. (2001), patients who chew betel nuts are prone to periodontal pathogen (Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis) hyperplasia, which manifests in clinical conditions such as gingival bleeding and periodontal bone loss, causing a considerable impact on dental implants [27]. In addition, because of the hardness of betel nuts, damage to fixtures with incomplete osseointegration during chewing can cause irreparable damage to implants. The analysis in this study revealed that the relationship between patients' alcohol consumption habits and late fixture failure are statistically significant (\(p<0.05\)), indicating that alcohol consumption affects periodontal bone loss after the occlusion of fixtures. Based on research by [PERSON] et al. (2005), patients with daily alcohol consumption of up to 100 g have a higher fixture bone loss rate compared to those without alcohol consumption [28]. Therefore, drinking habits are indeed relevant factors for dental implant failure. * Ridge augmentation  
Ridge augmentation is a common supplementary operation in implant surgeries, which is mostly used in the event of insufficient alveolar bone width and height. This study discovered that failures occurred in 12.5% of the fixtures that underwent ridge augmentation, which echoes the guided bone regeneration risk proposed by [PERSON] et al. (2003) [29]. * Location of implant  
Dental implants have differing functions and requirements according to their locations: they focus more on occlusal functions in the posterior area to grind food, whereas those in the anterior area are required for aesthetic functions. The posterior area can be divided into two locations: the premolars and molars. [PERSON] et al. (1997) collected 392 fixtures from 152 patients, and their statistical analysis after six years of tracking revealed that single molar implant prostheses have a higher failure occurrence than premolar implant prosthesis (\(p<0.001\)) [30]. The findings indicated that molars sustain a higher occlusal force compared to the premolars and thus have a greater chance of problems, up to 49.8%. In addition, if a distinction is made between the upper and lower jaws, the regression analysis by [PERSON] et al. (2003) demonstrated that upper jaws have a higher failure rate compared to lower jaws [29]; [PERSON] et al. (2005) also discovered that the upper jaw fixture failure rate (8.16%) is higher than that of lower jaw fixtures (4.93%), which is a significant difference (\(p<0.001\)) [31]. According to the [PERSON] et al. (2009), comparing the failure rates for differing implant locations in 194 patients, 6 years of tracking revealed that posterior teeth have a higher chance of failure occurrences [32]. The DT analysis in this study showed a similar result for the lower jaw premolars in the posterior area compared to those in other locations. This could be because the area is closer to the mental foramen, a crucial anatomical structure that causes difficulties for surgeons to implant fixtures in the correct position or perform ridge augmentation, thereby leading to further failure risk.