OBJECTIVES: The aim of this study was to evaluate different anatomical variants of the anterior loop of the inferior alveolar nerve (IAN) via cone-beam computed tomography (CBCT). MATERIALS AND METHODS: CBCT images of 71 patients (36 males and 35 females) were evaluated. We used the classification described by Solar for IAN evaluation. In this classification, three different types of IAN loops were introduced prior to emerging from the mental foramen. We classified patients according to this system and introduced a new, fourth type. RESULTS: Type I was seen in 15 sites (10.6%), type II in 39 sites (27.5%), and type III in 50 sites (35.2%). We found a new type in 38 sites (26.8%) that constituted a fourth type. CONCLUSION: We found that type III was the most common variant. In the fourth type, the IAN was not detectable because the main nerve was adjacent to the cortical plate and the incisive branch was thinner than the main branch and alongside it. In this type, more care is needed for surgeries including inferior alveolar and mental nerve transposition.
Cerebral Cortex ; Classification ; Cone-Beam Computed Tomography* ; Humans ; Iran ; Male ; Mandibular Nerve*

OBJECTIVES: Bone density seems to be an important factor affecting implant stability. The relationship between bone density and primary and secondary stability remains under debate. The aim of this study was to compare primary and secondary stability measured by resonance frequency analysis (RFA) between different bone types and to compare implant stability at different time points during 3 months of follow-up. MATERIALS AND METHODS: Our study included 65 implants (BioHorizons Implant Systems) with 3.8 or 4.6 mm diameter and 9 or 10.5 mm length in 59 patients. Bone quality was assessed by Lekholm-Zarb classification. After implant insertion, stability was measured by an Osstell device using RFA at three follow-up visits (immediately, 1 month, and 3 months after implant insertion). ANOVA test was used to compare primary and secondary stability between different bone types and between the three time points for each density type. RESULTS: There were 9 patients in type I, 18 patients in type II, 20 patients in type III, and 12 patients in type IV. Three implants failed, 1 in type I and 2 in type IV. Stability values decreased in the first month but increased during the following two months in all bone types. Statistical analysis showed no significant difference between RFA values of different bone types at each follow-up or between stability values of each bone type at different time points. CONCLUSION: According to our results, implant stability was not affected by bone density. It is difficult to reach a certain conclusion about the effect of bone density on implant stability as stability is affected by numerous factors.
Bone Density ; Classification ; Dental Implants ; Follow-Up Studies ; Humans

OBJECTIVES: Bone density seems to be an important factor affecting implant stability. The relationship between bone density and primary and secondary stability remains under debate. The aim of this study was to compare primary and secondary stability measured by resonance frequency analysis (RFA) between different bone types and to compare implant stability at different time points during 3 months of follow-up. MATERIALS AND METHODS: Our study included 65 implants (BioHorizons Implant Systems) with 3.8 or 4.6 mm diameter and 9 or 10.5 mm length in 59 patients. Bone quality was assessed by Lekholm-Zarb classification. After implant insertion, stability was measured by an Osstell device using RFA at three follow-up visits (immediately, 1 month, and 3 months after implant insertion). ANOVA test was used to compare primary and secondary stability between different bone types and between the three time points for each density type. RESULTS: There were 9 patients in type I, 18 patients in type II, 20 patients in type III, and 12 patients in type IV. Three implants failed, 1 in type I and 2 in type IV. Stability values decreased in the first month but increased during the following two months in all bone types. Statistical analysis showed no significant difference between RFA values of different bone types at each follow-up or between stability values of each bone type at different time points. CONCLUSION According to our results, implant stability was not affected by bone density. It is difficult to reach a certain conclusion about the effect of bone density on implant stability as stability is affected by numerous factors.