Long-term clinical and prosthetic outcomes of soft liner attachments for bar/implant overdentures were not sufficiently investigated. The aim of this trial was to evaluate clinical and prosthetic outcomes of resilient liner and clip attachments for bar/implant-retained mandibular overdenture after 7 years. Thirty edentulous male participants received two implants in the canine areas of the mandible. Three months later, implants were splinted with a resilient bar. Mandibular overdentures were connected to the bars with either clip (CR group, n = 15) or resilient liner (RR group, n = 15) attachments. Plaque index (PI), gingival index (GI), probing depth (PD), vertical bone loss (VBL), horizontal bone loss (HBLO) and prosthetic complications (PCs) were evaluated at denture delivery (T0), 6 (T ), 12 (T1), 24 (T2), 36 (T3), 48 (T4), 60 (T5), 72 (T6) and 84 (T7) months after insertion. PI and GI increased significantly with time for CR and decreased significantly for RR (P < 0·001). PD increased at T1 (CR) and T6 m (RR) and then decreased thereafter (P < 0·05). VBL increased significantly with time in both groups (P < 0·005). HBLO increased at T2 (CR) and T1 (RR) and then decreased thereafter. CR recorded significant higher PI, GI, PD, VBLO and HBLO compared to RR at all observation times (P < 0·042). The survival rates were 96·6% and 100% for CR and RR after 7 years. The most common PCs for CR and RR were clip wears and separation of the resilient liner from the denture base, respectively. Within the limitations of this study, resilient liner attachments are recommended for bar/implant-retained mandibular overdentures than clip attachments in terms of peri-implant tissue health and prosthetic complications after 7 years.

Purpose: The aim of this study was to evaluate biologic and prosthetic complications with acrylic and porcelain fixed hybrid prosthesis used for rehabilitation of edentulous mandible according to the "All on four" concept. Materials and methods: Ten edentulous patients received new maxillary and mandibular dentures. Four implants were inserted in the inter-foraminal area of the mandibular jaw according to the "All on four concept" and the implants were immediately loaded with lower denture. After 3 months, the patients were randomly assigned into two equal groups: Group I: received fixed ceramometal prosthesis (PFM), Group II; received metal acrylic hybrid prosthesis (MAP). Biological and prosthetic complications were measured for provisional dentures after 3 months of loading and for definitive prosthesis after 3 year. Results: The most common biological complication was increased pocket depth and bone loss which was significantly higher for PFM compared to MAP. Regarding provisional denture, the most common complication was denture fracture and prosthetic screw loosening. The most common complication for definitive prosthesis was crown fracture, teeth wear and prosthetic screw loosening. Crown fracture and teeth wear were higher in MAP and abutment screw loosening was higher in PFM. Conclusion: Within the limitation of the current study PFM and MAP could be used successfully for All on four implant rehabilitation of edentulous mandible. However, MAP may be advantageous than PFM regarding biologic complications (increased pocket depth and marginal bon loss) and abutment screw loosening. On the other hand, PFM may be preferred than MAP in terms of crown fracture and teeth wear/replacement.

Aim of the study:This study aimed to evaluate the effect of hyperbaric oxygen therapy on success rate of implants used to retain mandibular overdentures and possibility of osteonecrosis of the jaw in Bisphosphonate treated osteoporotic patients. Materials and methods:Eight systemic free patients were selected as control group (CG) and eight osteoporotic patients treating with Bisphosphonate drugs orally more than two years were selected as study group (SG). For both groups, patients received mandibular implant retained overdentures with locator anchors following two stage surgical protocol. Patients of study group were received Hyperbaric oxygen thereby (HBO) after the first stage surgery, while those of control group were not received (HBO). Peri-implant marginal bone height and density were evaluated at six months (T6), twelve months (T12) after insertion using Cone Beam Computed Tomography (CBCT). Results:No failure of dental implants were recorded with 100% cumulative survival rates for both groups. Both groups showed increase in bone density and decrease in marginal bone height through a period of one year follow-up. However, the group that received HBO therapy showed less marginal bone loss and more increase in bone density than the control group. Conclusion:Hyperbaric oxygen therapy is valuable and effective treatment for osteoporotic treated Bisphosphonate patients receiving implant retained mandibular overdentures as it eliminate the possibility of Bisphosphonate associated osteonecrosis of the jaw (BONJ), reduces bone loss and increase bone density around dental implant resulting in normal survival rate.

Objectives:The aim of the present trial was to compare clinical and radiographic outcomes of stress-free implant (SFI) bars and Milled bars for early loaded implant supporting mandibular overdentures. Materials and methods:Ten completely edentulous participants (6 males and 4 females) with sufficient bone anterior and posterior to the mental foramena received new maxillary and mandibular dentures. Patients were randomly allocated in 2 groups : group 1 include 5 patients who received milled bar overdentures, and group 2 include 5 patients who received SFI bar overdentures. Four implants were inserted according the flapless surgical protocol in canine and frist molar areas and early loaded by milled bar (group 1) or SFI bar (group2) 2 weeks after implant placement. Plaque and gingival indeces, pocket depth, fixture stability, and peri-implant bone resorption were measured at base line, 6 and 12 months after prostheis delivery. Results:The survival rate was 95% and 100% for milled bar and SFI bar groups respectively. Plaque index and pocket depth significantly increased with passage of time for milled bar group only and SFI bar showed no difference in these parameters between observation times. Bone loss increased from 6 to 12 months significantly in both groups. No significant differences in gingival index and fixture stability between observation times or between groups were noted. Milled bar group showed significant higher plaque, pocket depth, and bone resorption than SFI bar group after 6 and 12 months. Conclusion:Within the limitation of this randomized trial, it could be concluded that SFI bar is more advantageous for early loaded 4 implants supporting mandibular overdentures than milled bar as it was associated with decreased plaque accumulation, pocket depth and marginal bone resorption after one year.

Purpose: To evaluate in-vivo the effect of CAD/CAM constructed dentures on the masticatory muscles activity using electromyography in comparison to conventionally constructed dentures. Materials and Methods: Fourteen completely edentulous patients were randomly allocated to two equal groups. Patients in the first group received conventionally constructed complete dentures and patients in the second group received complete dentures constructed using CAD/CAM technology. After 30 days of denture use the anterior temporalis and superficial masseter muscles activity were measured by EMG. A cross over was performed for patients with conventional denture to CAD/CAM and vice versa and the dentures were used for further 30 days, after which measurements of anterior temporalis and superficial masseter muscles activity were taken using EMG. Electromyographic data was recorded and analyzed, mean values were compared by independent t-test to compare between the two groups as regard to muscle activity. Results: There was a significant difference in the activity of the masseter muscles and the anterior temporalis muscles for the patients received CAD/CAM denture in comparison to those received the conventional denture, after 30 days of denture use (p < 0.05). Conclusion: CAD/CAM constructed complete dentures produced higher muscle activity if compared to conventionally constructed complete dentures.

Objective: To evaluate and compare the peri-implant marginal bone height changes in two implant retained overdentures constructed by either CAD/CAM technology or conventional processing techniques. Background:The digital denture using CAD/CAM technology has proved high beneficial to the elders and/or the compromised edentulous patient, as it can help decrease the treatment burden on the patient by reducing the clinical procedures, number of visits, treatment time, and incurred costs. Materials and Methods:Twenty completely edentulous patients participated in this study. The patients were randomly allocated to two equal groups of patients (Group A and group B). Group A patients received complete dentures constructed by conventional heat cured technique. Group B patients received complete dentures constructed by CAD/CAM technology. All the patients received two root form implants bilaterally in the canine regions following delayed loading protocol. Locator attachment was then used to retain the overdenture after 3 months healing period. Marginal bone height was radiographically evaluated at baseline, 6 and 12 months after implant loading.Results: There was a significant loss in marginal bone height around the supporting implants in each study group. However, no significant differences in marginal bone height were recorded between the study groups over the observation period (P > 0.05). Conclusion:Peri-implant marginal bone height changes with overdentures fabricated by CAD/ CAM technique are not different from those changes with overdentures fabricated by a conventional heat curd technique.