Complete Mandibular Overdentures Research Articles

The impact of chewing force simulation on stress distribution of implant retained mandibular overdenture with locator attachment system having matrix of PEEK versus nylon insert

The current study investigates the impact of chewing force simulation on stress strain distribution of Mandibular overdentures retained with locator attachment system having matrix of PEEK versus nylon insert. Twenty completely edentulous mandibular digitally printed models were fabricated with beds for two implants, which had been inserted in the estimated canine positions with two grooves mesial and distal at each implant site for the attachment of the strain gauges for each model. Nova loc group NLG with ten implant assisted mandibular complete overdentures were fabricated over ten printed models with nova loc attachments while locator group LG had ten implant assisted mandibular complete overdentures over ten printed models with locator attachments of same retaining force and geometric height. Bilateral vertical load was applied with a universal testing machine and strain induced to the implants was measured around the two implants medially and distally in each group using strain gauges pre & post one year simulated functional aging. Student t test was used for comparing the two types of attachments while paired t test was used for comparison of strain induced to the implants after one year of functional aging, with probability level p < 0.05 is considered statistically significant. Individual statistical analysis of the data revealed increase in the number of measured strains for both attachments which was statistically significant for locator. Comparing the two groups, significant increase for the locator attachment after one year simulated functional aging was detected compared to nova loc. Within the limitations of this study, one year simulated functional aging seems to cause disturbance in the load conveyed to the supporting structures of mandibular implant assisted overdenture retained with locator in contrast to nova loc that showed more resistance to aging process, thus nova loc attachment transmit less stresses than locator attachment to the surrounding implants supporting structures specially after time of service related to its combined materials superior physical properties.

Surface Wear and Retention Force of Zirconia and PEKK Implant-retained Crowns.

The aim of this study was to evaluate the surface wear and retention force of telescopic attachments made of zirconia primary crowns and poly-ether- ketone -ketone (PEKK) secondary crowns for 2-implant retained mandibular complete overdentures. Ten healthy completely edentulous patients aged 55-60 years were selected for this study. Each patient received two implants in the mandibular canine regions. Maxillary conventional complete dentures were constructed against implant-retained mandibular overdentures for all patients. Zirconia- PEKK telescopic attachments were fabricated to retain the overdentures where primary copings were constructed of zirconia and secondary ones were constructed of PEKK. Retention force and surface wear were evaluated at the time of overdenture insertion (T0), and after 6 months of overdenture use (T6). The results revealed less wear of zirconia copings compared to PEKK ones at T0 and T6. However, both materials showed insignificant wear after 6 months of overdenture use. A significant increase in retention force was observed after 6 months of overdenture use. Within limitations of this study, PEKK may be considered a promising alternative material for telescopic secondary crowns construction combined to zirconia primary ones, regarding the wear resistance and the satisfactory retention forces.

A comparative study to evaluate microstrain of low-profile attachment associated with and without bar connection in implant assisted mandibular overdenture (in vitro study)

BackgroundThe aim of this study was to compare the microstrain transmitted to peri-implant tissues of implant-assisted mandibular overdentures using two different low-profile attachment designs; OT- Equator attachment with and without bar attachment.Materials and methodsA completely edentulous epoxy resin mandibular model was used, in which two parallel dental implants were inserted at the canine region bilaterally and one in the middle. Sixteen identical complete edentulous mandibular overdentures were fabricated following conventional, standardized techniques and were divided equally between two groups according to the design and placement of the OT-Equator. Group A implants were kept solitary with an OT-Equator attachment, while group B implants were kept splinted with a bar associated with two mini-OT-Equator attachments in between. Sixteen identical mandibular complete overdentures were constructed, to which attachments were picked up. The difference in stress distribution was measured using strain gauges and compared between the two studied groups. A vertical load of 100 N using the universal testing machine was applied unilaterally on the left mesial fossae of the mandibular first molar and bilaterally on the bar attached to the mandibular premolar molar region of the overdentures. Statistical analysis was conducted using IBM SPSS version 28. Normality was checked by using the Shapiro-Wilk test and normality plots. The Mann-Whitney U test was then used to analogize the groups.ResultsThere was a statistically significant difference between groups A and B upon application of vertical unilateral and bilateral loadings of 100 N, with mean microstrain values of P 0.05. Group A (OT-Equator attachment) showed lower strain values than Group B (OT-Equator bar attachment) upon application of vertical, unilateral, and bilateral loadings of 100 N.ConclusionsImplant-assisted mandibular overdenture with a solitary attachment is associated with lower microstrain values around the implants after application of unilateral and bilateral vertical loadings of 100 N.

EFFECT OF DENTAL IMPLANTS SURFACE TREATMENT ON MARGINAL BONE HIGHT

Statement of problem:Marginal bone changes around implant supported complete dentures is one of the most significant factor that affect the clinical success of dental implants which depends mainly on osteointegration and surface treatment. Purpose. This study aimed to assess the change in marginal bone height of two different surface treated implants retaining and supporting complete overdenture. Materials and Methods.50-60 yearsoldcompletelyedentulous patients wereselectedandand rehabilitatedwithmaxillarycomplete dentures and mandibularoverdenturesretained by twoball and socket dental implants. The implants surface treatmentsusedwereacidetch andresorbable blast media (RBM). Marginal boneheight changes wereassessed at denture insertion, after six- and twelve-monthusingconebeamcomputedtomography (CBCT). Date wascollected and Students t-test wasperformed. Results. The change of marginal bone of the acid etched and RPM implants throughout the follow up periods showed no significant statistical difference among the two type of implants at time of loading, after the 6th and 12th month. Conclusions. Acid etchedandRBM dental implants supporting and retaining complete mandibular overdentures showed significant success rates regarding the marginal bone changes during the follow up period. Clinical Implications: Guided implant placementgranting more accurate and predictable implant position while reducing the patient fear and anxiety. The marginal bone level changes were within the reported range of the literature of both acid etched and RBM dental Implants.

Clinical and Radiographic Evaluation of Marginal Bone Level (BL) in Two Implant-Retained Mandibular Overdenture With Lingualized Occlusion (LO): A Six-Year Clinical Trial.

The objective of this research was to assess the marginal bone loss and stability in a lingualized occlusal scheme with implant-supportedmandibular overdenturesas a viable solution for individuals experiencing difficulties with the retention of conventional mandibular dentures. The study assessed the marginal bone level (BL) using radiographic evaluation and clinically by evaluating periodontal health using probing depth indexvalues over a period of 6 years. Ten completely edentulous male patients with a bone height (BH) of 15-25 mm at the mandibular symphyseal region and dissatisfaction with their mandibular conventional complete denture were included in the study. Patients were willing to accept the conditions of the study and provide informed consent. Bleeding index, plaque index (PI), probing depth, and crestal BL were accessed during the follow-up period. Marginal BLs using Wical and Swoop Analysis method were evaluated at baseline (BL) (during loading), 3 yearsand 6 years post-loading. During the observation period, there was no incidence of implant loss, and all patients expressed contentment with the retention, stability, chewing functionality, and esthetic appeal of their dentures.Marginal BLs through clinical and radiographic evaluation, periodontal health using bleeding on probing (BOP), and probing depth were assessed during the follow-up period. Throughout the entire period of observation, no instances of implant displacement were detected. The study found that the use of a lingualized occlusal scheme with two implant-retained mandibular complete overdenture effectively transmitted horizontal loads, reduced stress on individual implants leading to decreased bone loss, and increased stability.

Effect of Different Implants Number and Distributions Used to Assist Mandibular Complete Overdenture: A Study of Bite

Effect of Different Implants Number and Distributions Used to Assist Mandibular Complete Overdenture: A Study of Bite

Radiographic Evaluation of Bar/Locator versus Bar/ball for Implant Assisted Complete Mandibular Overdenture (A 5-Year Retrospective Study).

Radiographic Evaluation of Bar/Locator versus Bar/ball for Implant Assisted Complete Mandibular Overdenture (A 5-Year Retrospective Study).

Integrating Analog and Digital Workflow to Fabricate Implant Mandibular Complete Overdenture with a Milled Titanium Bar: A Clinical Report.

Implant mandibular complete overdenture (IMCO) is a reliable prosthetic option. However, clinical and laboratory complications are associated with these restorations if not executed properly. In this clinical report, the combination of analog and digital workflow helps minimize the chairside time with fewer visits, which improves efficiency and patient satisfaction. Int J Periodontics Restorative Dent 2023;43:e111-e115. doi: 10.11607/prd.5975.

Comparison between conventional and 3D printed implant retained mandibular complete overdentures regarding occlusion using digital occlusion analysis system (A pilot study)

Comparison between conventional and 3D printed implant retained mandibular complete overdentures regarding occlusion using digital occlusion analysis system (A pilot study)

Evaluation of Two Types of Surface Treatment of Implants Supported Mandibular Complete Overdentures

Evaluation of Two Types of Surface Treatment of Implants Supported Mandibular Complete Overdentures

Retention and Stress Distribution of Implant Retained mandibular Complete Overdenture with Locator versus Ball and socket Attachments (An in vitro Study)

Retention and Stress Distribution of Implant Retained mandibular Complete Overdenture with Locator versus Ball and socket Attachments (An in vitro Study)

Evaluation of Retention and Attachment Wear of CAD/CAM Versus Conventional Implant-Assisted Overdenture Frameworks.

Previous studies have demonstrated problems with implant-supported overdenture attachments, such as denture base fracture and retention loss of the attachment's nylon insert. In this study, three implants were surgically inserted at the anterior mandibular region of 16 completely edentulous men (mean age: 50 years), divided into two groups depending on the received mandibular complete overdenture: a conventional metal-reinforced framework with prefabricated metal housing (Group I) or a CAD/CAM metal-reinforced framework with custom metal housing (Group II). At 3 months (prostheses loading), 6 months, and 12 months after implant placement, the retention of the mandibular dentures and wear of O-ring attachments were evaluated. Data were collected, tabulated, and statistically analyzed using Student t test. Statistically significant differences were found between the two groups and within the same groups during the evaluation period (P < .05). Attachment housing incorporated within a CAD/CAM implant overdenture can be a better alternative to the manufacturer's metal housing, as it diminishes retention loss and attachment wear over time, thus increasing patient satisfaction and chewing efficiency.

Retention and stress distribution induced in mandibular implant-retained complete overdenture with different interimplant distance (An In-Vitro study).

Retention and stress distribution induced in mandibular implant-retained complete overdenture with different interimplant distance (An In-Vitro study).

Quality of Life and Patient Satisfaction with Complete Dentures versus Mandibular Overdentures

Quality of Life and Patient Satisfaction with Complete Dentures versus Mandibular Overdentures

Comparison Between Two Different Design Concepts of 4- Implant Assisted Mandibular Complete Overdenture:- periimplant bone height changes

Abstract:&#x0D; Purpose: This study was accomplished to evaluate the bone height changes radiographically and the reliability of use either two posterior short or inclined implants with two conventional anterior implants retaining mandibular overdenture.&#x0D; &#x0D; Materials and methods: Ten male mandibular completely edentulous patients were divided in two equal groups after delivered complete dentures. For the first group (short implant design- group A) two vertical implants were inserted in the canine areas and two short vertical implants were inserted in the 1st molar area. For the second group (inclined implant design- group B) two vertical implants were inserted in the canine areas and two 30o distally inclined implants were inserted in the second premolar area. Digital standardized periapical radiographic assessment for horizontal and vertical alveolar bone height changes was carried out at T0 (immediately), T6 (6 months), T12 (12 months) and after mandibular complete overdenture insertion.&#x0D; Result: 1. VBL decrease significantly with advance of time in both groups during the time intervals. The highest VBL around the implants was noted in the 1st six months followed by the 2nd six months, the highest amount of total VBL observed with the interval T0-T12, followed by the interval (T0-T6) and the inclined implant group showed significant higher total VBL than short implant group at the intervals T0-T6 and T0-12.&#x0D; 2- HBL decreased significantly with advance of time in both groups. For short and inclined implant group, the highest amount of total HBL observed with the interval T0-T12, followed by the interval (T0-T6). Short implant group showed significant higher total HBL than inclined group at the interval T0-T6 and T0-T12.&#x0D; &#x0D; Conclusion: Within the limitations of this clinical radiographic study it can be concluded that (1) The 30o distally inclined implants inserted in the posterior areas for assisting mandibular complete overdenture induce vertical bone loss more than the axially inserted implants (short or conventional implants). (2) The short implants inserted in the posterior areas for assisting mandibular complete overdenture induce horizontal bone loss more than the axially inserted implants.&#x0D; Keywords: Short implants, O-ring ball attachment, VBL, HBL.&#x0D;

Thermocycling Effect on Implant Supported Overdenture Using 3D printed Peek Bar following all-on-4 Concept: Randomized Trial-In vitro Study

Objective: Stress analysis and retention evaluation of implant-retained mandibular complete overdenture with different clip materials and distributions. Methods: This in-vitro study was conducted over implants retained mandibular complete overdenture (all-on-4 concept) using BIOHPP bar attachments constructed using 3 D printing with different clip materials and distributions. This study consisted of 4 groups according to the type and distribution of clips: Group I: hard clips anteriorly and posteriorly, Group II: soft clips anteriorly and posteriorly, Group III: hard clips anteriorly and soft clips posteriorly, and Group IV: soft clips anteriorly and hard clips posteriorly. Stress analysis and retention were evaluated before and thermocycling afterward. Results: Comparison between stresses in each group before and after thermocycling in central and peripheral implants was performed, revealing stresses in all groups after thermocycling were significantly higher than before thermocycling as P < 0.05. Regarding retention, a comparison between all groups revealed a significant difference between them before and after thermocycling as P<0.05. Conclusion: There is no effect of clip material distribution regarding stress analysis and retention before and after thermocycling except stresses in central implant before thermocycling as soft clips anteriorly and hard clips posteriorly revealed significant lower stresses than hard clips anteriorly and soft clips posteriorly.

Comparison of stud and telescopic crown attachments for mini-implant retained mandibular complete overdentures

Objectives: Is to make a radiographic and bite force comparison between stud and double telescopic crowns as two different attachment systems for two interforaminal mini implants retaining mandibular complete overdenture. Subjects and materials: Randomized, controlled, clinical study was done on 20 completely edentulous patients that divided into 2 equal groups, in The first group (study group), patients were treated by two mini-implants (with ball abutments) of 2.4mm diameters and 13mm lengths (in the canine regions) retaining mandibular overdentures and by conventional maxillary complete dentures, in The second group (control group), patients were treated by two mini-implants (with square head abutments) of 2.4mm diameters and 13mm lengths (in the canine regions) retaining mandibular overdentures and by conventional maxillary complete dentures. Results: At the end of the 12 months, a total loss of 0.69 mm for group I (with ball abutments), and 1.64 mm for group II (with square head abutments) was detected. For Maximum Bite Force, there was no significant difference between the two groups at all follow-up periods. Conclusion: Mandibular overdentures retained by two mini implants considered an acceptable treatment modality over the one-year observation period. Ball attachments are more favorable than telescopic attachments, in regard to the reduction of the peri-implant bone loss, while, the type of the attachment has less effect on the maximum bite force.

Patient-reported outcomes for the immediate loading of mandibular overdentures supported by two implants soon after implant surgery

Background/purposeNo studies have comprehensively assessed short-term patient-reported outcomes after the provision of overdentures supported by two immediate implants. The purpose of this study was to evaluate short-term patient-reported outcomes for mandibular overdentures retained by ball attachments on two immediately loaded implants. Materials and methodsNineteen participants with mandibular edentulism were provided with overdentures retained by ball attachments on two immediately loaded, unsplinted implants. The participants' self-assessment of their dentures and oral health-related quality of life were evaluated with the 22-item Patient's Denture Assessment (PDA), and the 19-item Japanese version of the Oral Health Impact Profile (OHIP-EDENT), respectively. Patient satisfaction was measured on a 100 mm visual analogue scale. Assessments were conducted at baseline, and at 1 and 6 months after implant surgery. ResultsThere were significant increases in the PDA “Lower denture” (P = 0.009) at 1 month, as well as “Function” (P = 0.002) and “Lower denture” (P = 0.009) scores at 6 months. Patient satisfaction was also significantly increased at 1 month (P = 0.007) and 6 months (P ≤ 0.000). Significant decreases were observed in the OHIP-EDENT “Physical pain” (P = 0.046) score at 1 month, as well as the summary score (P = 0.033), “Functional limitation” (P = 0.020) and “Psychological discomfort” (P = 0.019) scores at 6 months. ConclusionThe use of two immediately loaded implants for lower mandibular complete overdentures is associated with improvements in patient's self-assessment of dentures, satisfaction, and oral health-related quality of life, up to 6 months after implant surgery.

Retention of different non-metal single crown coping supporting single implant mandibular overdenture (in - vitro study)

Purpose: This study aimed to evaluate the retention of single implant mandibular overdenture using different single crown coping materials. Materials and Methods: Clear acrylic resin mandibular cast was fabricated with single implant located in the mid-line of the cast. The cast with the implant was scanned for designing of nine copings of different materials using computer aided design computer aided manufacture CAD/CAM and according to material used for copings fabrication, models were categorized as follow: Poly etherether ketone (PEEK) group, Zirconium dioxide (ZrO2) group, hybrid composite resin coping group. Nine identical mandibular complete overdentures were constructed, tensile force for removing overdenture with copings was then recorded. Results: Comparison of recorded tensile strength results showed a significant difference among groups where the highest retention was recorded with Zirconia group, followed by PEEK and the lowest retention results were noted with Hybrid composite resin. Conclusion: Within the limitation of this in vitro study, it could be concluded that single crown that fabricated from ZrO2 for supporting implant supported overdenture showed better retention results in comparison to PEEK a hybrid composite one.

Mandibular bone height changes in two different design concepts of four implant assisted overdenture

Purpose: This comparative study was conducted to compare between two different design concepts of four implant assisted complete mandibular overdenture regarding the residual alveolar bone height changes.Materials and Methods: Ten healthy completely edentulous male patients were selected for this study. For each patient, a conventional complete denture was constructed. Each mandibular denture was duplicated to be used as a radiographic stent, then the CBCT surgical guide template was printed according to each design concept of 4-implant overdenture. The CBCT surgical guide templates were used for installing the implants according to flapless surgical technique followed by delayed loading. According to the two design concepts of the 4-implant overdenture used in this study, the patients were randomly classified into two equal groups: group [A]had two vertical canine implants with two axial 1st molar short implants (short design concept), and group [B]had two vertical canine implants with two distally inclined premolar implants (inclined design concept). Radiographic evaluations were performed immediately (T0), 6 months (T6), and 12 months (T12) respectively after picking up of the ball attachments.