Objectives: The purpose of this study was to three-dimensionally evaluate the relationship between the degree of bilateral impacted mandibular third molars (IM3M) angulation and the mandibular dental arch parameters in normal skeletal and dental malocclusion patients. Materials and Methods: In this retrospective cross-sectional comparative study, 120 adult subjects’ cone beam computed tomography (CBCT) images were three-dimensionally analyzed. The sample was divided into four groups according to degree of M3M buccolingual angulation (BL°); Group A <12° on the center of the ridge (N=30), Group B 12-24° off-center of the ridge (N=40), Group C >24° off center of the ridge (N=30), and Group D (control group with normal erupted bilateral M3M).The study subjects were further also divided into three groups according to IM3M mesiodistal angulation (MD°); Group 1 from10° to 45°, Group 2> 45° and Group 3 (control group with normal erupted bilateral M3M, 0 -10°). Comparison within and between groups were performed using One-way ANOVA followed by Tukey's post hoc test, respectively. Correlation between IM3M, BL and MD angulation and mandibular arch parameter was calculated using Pearson's correlation coefficient. Results: Statistically significant differences (P < .001) were founded between the IM3M BL° and anterior teeth inclination, arch length (AL) and inter second molar width (inter 2nd MW) as well as between the IM3M MD° with anterior crowding and the arch length (P < .001). Significant positive correlation was founded between IM3M BL° and anterior teeth inclination, and between IM3M MD° and anterior teeth crowding and inter 2nd MW. Significant negative correlation was observed between IM3M BL° and inter 1st MW and 2nd MW. Conclusion: The degree of buccolingual and mesiodistal angulation of the impacted mandibular third molars was associated with mandibular dentoalveolar changes. The increase in buccolingual angulation is associated with increase of anterior teeth inclination, and the decrease of 1st and 2nd inter-molars width. The increase in mesiodistal angulations was associated with increase in anterior teeth crowding and 2nd inter-molars width. Clinical relevance: Assessment of the relationship between the impacted mandibular third molars and the degree of arch discrepancy, and the position of mandibular incisors in the three planes of space might help in the decision-making process for extraction of the impacted third molars in adult patients.

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Objectives: The purpose of this study was to three-dimensionally evaluate the relationship between the degree of bilateral impacted mandibular third molars (IM3M) angulation and the mandibular dental arch parameters in normal skeletal and dental malocclusion patients.Materials and Methods: In this retrospective cross-sectional comparative study, 120 adult subjects' cone beam computed tomography (CBCT) images were three-dimensionally analyzed. The sample was divided into four groups according to degree of M3M buccolingual angulation (BL°); Group A <12° on the center of the ridge (N=30), Group B 12-24° off-center of the ridge (N=40), Group C >24° off center of the ridge (N=30), and Group D (control group with normal erupted bilateral M3M).The study subjects were further also divided into three groups according to IM3M mesiodistal angulation (MD°); Group 1 from10° to 45°, Group 2> 45° and Group 3 (control group with normal erupted bilateral M3M, 0 -10°). Comparison within and between groups were performed using One-way ANOVA followed by Tukey's post hoc test, respectively. Correlation between IM3M, BL and MD angulation and mandibular arch parameter was calculated using Pearson's correlation coe cient.Results: Statistically signi cant differences (P < .001) were founded between the IM3M BL° and anterior teeth inclination, arch length (AL) and inter second molar width (inter 2 nd MW) as well as between the IM3M MD° with anterior crowding and the arch length (P < .001). Signi cant positive correlation was founded between IM3M BL° and anterior teeth inclination, and between IM3M MD° and anterior teeth crowding and inter 2nd MW. Signi cant negative correlation was observed between IM3M BL° and inter 1 st MW and 2 nd MW. Conclusion:The degree of buccolingual and mesiodistal angulation of the impacted mandibular third molars was associated with mandibular dentoalveolar changes. The increase in buccolingual angulation is associated with increase of anterior teeth inclination, and the decrease of 1 st and 2 nd inter-molars width. The increase in mesiodistal angulations was associated with increase in anterior teeth crowding and 2 nd inter-molars width.Clinical relevance: Assessment of the relationship between the impacted mandibular third molars and the degree of arch discrepancy, and the position of mandibular incisors in the three planes of space might help in the decision-making process for extraction of the impacted third molars in adult patients.

Objectives To evaluate treatment success, patient satisfaction, and oral health-related quality of life (OHRQoL) after rehabilitation of atrophic edentulous maxilla (AEM) with six implants placed simultaneously with bilateral maxillary sinus floor augmentation (MSFA). Materials and methods The selected patients were fully edentulous with atrophic maxillary posterior residual ridges, who rehabilitated with 6 implants placed simultaneously with bilateral MSFA and immediate all-on-4 provisional fixed prosthesis (PFP). After 7–12 months of implant surgery, all patients have received all-on-6 definitive fixed prosthesis (DFP). After at least one year of function with DFP, the clinical and radiographic examinations were performed. Patient satisfaction with DFP was assessed through a visual analog scale (VAS). The OHRQoL before treatment (T0), during provisional (T1), and after definitive prosthesis (T2) was evaluated using OHI-14. Results 20 maxillary edentulous patients were rehabilitated with 120 implants (6 for each maxilla combined with bilateral MSFA), 20 immediate all-on-4 PFP, and 20 all-on-6 DFP. Of those,12 patients have passed at least year follow-up after DFP insertion, and were eligible to be included for the assessment of treatment success. After a mean of 20 (12–36) months follow-up, the implant and prosthesis survival rate were both 100%. The success rate at the implant level was 98.6%. The peri-implant soft tissue condition was stable without biological complications. The mean marginal bone loss (MBL) was 0.09 ± 0.06 mm. No prosthetic or postoperative complications was observed. The patient satisfaction after treatment was high and the mean general satisfaction was (91.75 ± 7.06). There was a significant improvement in most OHIP-14 domains during the provisional all-on-4 (T1) and in all domains during the final all-on-6 prosthesis (T2) (P < 0.01). Conclusions Rehabilitation of the AEM utilizing six implants combined with simultaneous bilateral MSFA, immediate All-on-4 PFP, and delayed All-on-6 DFP is a successful treatment approach associated with minimal postoperative complications high patient satisfaction, significant improvement in OHRQoL. Clinical relevance: Rehabilitation of AEM with six implants inserted simultaneously with bilateral MSFA enables the prosthesis to restore/extend to the first or second molars without a cantilever, which improves clinical outcome and OHRQoL compared to cantilevered and shortened dental arch concept prosthesis.