Conventional Maxillary Dentures Research Articles

Comparative evaluation of masticatory efficiency, clinical performance, and patient satisfaction of single implant-retained mandibular overdenture versus conventional complete denture: A prospective in vivo study.

The aim of this within-subject prospective clinical study was to investigate the scope of single implant mandibular overdenture by assessing its masticatory efficiency, clinical performance, and patient satisfaction compared to conventional complete dentures. Prospective In Vivo Study. This prospective in vivo study was conducted in the Department of Prosthodontics and Crown and Bridge, Christian Dental College, Ludhiana. A total of 12 completely edentulous patients received a single implant in the mandibular anterior midline region. After the healing period, the conventional maxillary and mandibular dentures were fabricated. 15 days post insertion of the conventional dentures, patients were evaluated for masticatory efficiency, clinical performance including retention and stability, and patient satisfaction. To evaluate the masticatory efficiency blue raspberry and original pink "Hubba Bubba tape gum" were used as a test food. Colorimetric analysis was done to assess variance of hue. To assess clinical performance, retention, and stability of the mandibular denture was recorded using a digital force gauge and was tabulated as per CU-modified Kapur's criteria. OHIP-14 index was used to assess patient satisfaction. After evaluation of the parameters of conventional dentures, the denture was converted into an implant-retained mandibular denture by chairside conversion with locator attachments. 15 days post-implant loading, parameters of the implant retained mandibular overdenture were assessed again followed by statistical analysis. The masticatory efficiency was assessed using a paired t-test. The patient satisfaction was sequentially assessed with Wilcoxon signed rank test and thereafter paired t-test was used to compare between conventional complete denture and overdenture. Clinical performance was assessed using the Wilcoxon signed rank test. The masticatory efficiency of single implant mandibular overdenture was higher than that of conventional complete dentures. The clinical performance of the overdenture was higher than that of the conventional denture. Stability being a time-dependent parameter might need longer follow-ups for further conclusions. Patient satisfaction with single implant retained overdenture was significantly higher than conventional complete dentures. Single implant mandibular overdenture has improved masticatory efficiency, clinical performance, and patient satisfaction compared to conventional complete dentures.

Conventional maxillary denture versus maxillary implant-supported overdenture opposing mandibular implant-supported overdenture: Patient's satisfaction.

This study sought to determine the impact of age, gender, and use of maxillary implant-supported overdenture (UISOD) versus conventional denture (CMD) opposing mandibular implant-supported overdenture (LISOD) and the number of years the patient has used their prosthesis on the ratings of satisfaction. This study aimed to assess the long-term influence of different factors on patients'satisfaction with LISODs needing a maxillary prosthesis, helping dentists choose a treatment pathway that leads to a higher satisfaction rate. This cross-sectional study included 84 participants. They were treated with LISOD opposing either CMD or UISOD from 2015 to 2020. They were all eligible to participate in the study. An oral health impact profile (OHIP-14) questionnaire was given to each patient and filled out by them. OHIP-14 scores were gathered and went under statistical analysis with PASS-11 software to determine the relationship between patients'satisfaction with the scores. Age and gender had no significant influence on how satisfied patients were. Patients with maxillary overdentures showed more satisfaction than the CMD group (p < .05). Moreover, patients'satisfaction decreased with increasing years of prostheses usage (p < .05). This study demonstrated that satisfaction is related to the type of maxillary prosthesis (conventional or implant-supported) used opposing LISODs and the number of years the patient had used the prostheses.

Two or four implants for maxillary overdentures in edentulous patients: 1-year results of a randomized controlled trial.

Maxillary implant overdenture therapy is a good treatment option for treating patients experiencing problems with their conventional maxillary denture. Retaining the overdenture with four implants and a bar attachment system serves as the current gold standard. However, there is a demand for less costly and less invasive treatment options. The aim of this randomized controlled trial was to compare marginal bone level change (MBLC), implant and overdenture survival, clinical, masticatory, and patient-related outcomes (PROMs) of maxillary implant overdentures with either two or four implants and a bar attachment system. Forty edentulous participants were randomly allocated to two groups (n = 20), to receive either two or four implants in the maxilla. After healing, all the participants received an implant overdenture retained by a bar attachment system. All the participants were evaluated 1 and 12 months after overdenture placement. The primary outcome was MBLC. Secondary outcomes were implant and overdenture survival, clinical, masticatory, and PROMs. The outcomes were analyzed using parametric and non-parametric tests. MBLC was -0.03 mm in the 2-implant group and -0.16 mm in the 4-implant group (p = 0.21). Implant survival was 83.3% in the 2-implant group and 94.4% in the 4-implant group (p = 0.03). The median pocket depth change and clinical outcomes were low, and masticatory performance along with PROMs improved in both groups and did not differ significantly between them. Maxillary 4-implant overdentures perform better than maxillary 2-implant overdentures with a bar attachment system in terms of implant and overdenture survival and therefore remains the gold standard. However, both overdentures perform similarly in terms of MBLC, clinical, masticatory, and PROMs.

Willingness to accept or refuse mandibular implant overdenture treatment: A prospective study on edentulous enrolled in a clinical trial.

Several complete denture wearers have major complaints and may be benefitted from implant treatment. However, the factors that shape the demand for and utilization of implants need further investigation. The aim was to evaluate edentulous patient's willingness to accept or refuse the offer and provision of implant-retained treatment. As part of a clinical trial, edentulous subjects were offered a mandibular overdenture retained by four mini-implants opposing a conventional maxillary denture. Treatment was offered without any financial costs for the patients. Patients' level of interest in receiving treatment was assessed using a 5-point Likert scale, and they were asked to respond to a list of reasons that led to their decision to accept or refuse implants. Those who refused implants received conventional prosthodontic interventions as required, and those who accepted implant treatment underwent surgical planning and implant placement. Of 175 eligible subjects, 147 accepted the offer of treatment and were invited to take part in the study (69.4% women, mean age 67.4± 10.0 years). Overall, 111 patients (75.5%) expressed a positive intention to undergo implant treatment at the initial contact. Implant treatment was performed for 56.3% (9/16) of those who answered 'probably yes' about their level of interest in implant treatment on the Likert scale, and 69.6% (64/92) of 'certainly yes' (p< .001). Older subjects were less likely to receive implants (OR=0.93; p= .036), whilst those with a positive intention towards implants (OR=3.15; p= .001), those previously treated by the dental team (OR=7.89; p< .001), and who actively demanded implants (OR=18.1; p< .001) were more likely to accept treatment. Improved chewing was the most common reason for accepting implants, whilst fear of surgery was the most reported reason for refusal. Refusal of implants was high among edentate patients even when financial costs were removed. Patients' initial attitude towards acceptance is a key factor in the demand for and uptake of implant therapy.

A Randomised Clinical Study of the Effect of a Denture Soft Liner on Mandibular Ridge Resorption in Complete Denture Wearers After One and Two Years Of Denture Insertion

Abstract: Aim: The aim of this study was to assess the effect of soft denture liners on mandibular ridge resorption in complete denture wearers after two years of use. Methodology: The study included 32 patients ranging in age from 35 to 65 years old. Those patients were completely edentulous with well formed ridges, Class I relation and no medical problem. Thirty two selected patients were divided into two groups, namely Experimental group and Control group. Control group (n = 16, 8 males and 8 females) received conventional maxillary and mandibular complete dentures. Whereas in Experimental group, (n = 16, 8 males and 8 females) silicone lined lower complete denture were made. Three panoramic radiographs (orthopantomogram [OPG]) were taken for each participant to assess the amount of bone resorption; immediately, one year, and two years after denture insertion. For comparing two groups at three different time intervals, analysis of variance (ANOVA) two way with post-hoc tests was used. A statistically significant pvalue of less than 0.05 was considered. Results: After denture delivery, there was significant change in bone height in all patients ( p &lt; 0.001) . The comparison of bone height between the two groups in different regions at different time intervals revealed a significant difference in bone levels at baseline to one year and baseline to two years. However, Experimental group experienced 50% less bone loss than control group over a two-year period. Conclusion: Based on the findings of the current study, it can be inferred that use of soft liners helps in reducing residual ridge resorption significantly when compared with conventional denture material.

Effect of Posterior Residual Ridge Resorption and Relining for Mandibular Implant Overdentures on Bending Strain Around Implants.

To examine the influence of posterior residual ridge resorption (PRRR) and relining on bending strain around implants under an overdenture. Maxillary and mandibular edentulous models were made and covered with white silicone. Four strain gauges were placed on four sides of each implant. Two tissue-level implants were placed bilaterally in the part between the lateral incisors and canines of the mandible. A maxillary conventional denture and a mandibular overdenture were fabricated to fit the models. Three levels of bone resorption around the implant were created: 0, 0.8, and 1.5 mm. The surface of the residual ridge was uniformly removed from the area near the distal side of the implant to the retromolar section, and three levels of PRRR were created (0, 1, and 1.5 mm). After the measurement, the experimental denture of the PRRR of 1 mm and 1.5 mm were relined. Locator attachments were used. A 98-N occlusal force was applied, and bending strains around the implant were measured. The Kruskal-Wallis test and Bonferroni correction were employed to analyze the data. Without relining, at each bone resorption level around the implant, the bending strain was smallest with PRRR of 0 mm and largest with PRRR of 1.5 mm. The bending strain after relining was smaller than the bending strain with ridge resorption. Bending strains after relining were smaller than bending strains with no ridge resorption, but there was no significant difference in bending strain between these three groups. As PRRR increased, the bending strain increased without relining. As bone resorption around the implant progressed, PRRR enhanced the increase in the peri-implant bending strain. Bending strain was reduced when relining was performed.

Rehabilitation of severly resorbed mandibular ridge with implant supported overdenture with magnet attachment : A case report.

Magnets have been used widely in the field of dentistry for many years with some success, as they can be manufactured in small dimensions as a retentive devices in overdenture technique, maxillofacial prosthesis and obturators. These magnet attachment attached to osseointegrated implants which transfer the occlusal load to the bone, thereby prevent resorption of remaining alveolar bone and improves the retention and stability of the denture. Magnetic assembly consist of magnet and ferromagnetic metal keeper. More recently, magnets have been made from alloys of the rare earth elements samarium and neodymium, which provides stronger magnetic force per unit size. Magnets are sealed by means of the latest laser lasing techniques thus protect magnet from corrosion in oral cavity. The present article demonstrates the rehabilitation of completely edentulous patient with the help of implant supported mandibular overdenture with magnet attachment and conventional maxillary denture.

A comparative study of patients satisfaction with conventional and relined mandibular complete dentures

Edentulous patients are usually satisfied with the service of a conventional maxillary denture but not the mandibular denture, particularly if the patients present with advanced atrophy of residual ridges, systemic diseases, chronic tissue soreness or maladaptive denture wearing experience. For such patients, the relining of hard heat cured mandibular dentures with long term resilient denture liners may be considered as a non-surgical alternative to pre-prosthetic procedures or implant supported prostheses. Purpose of The Study: The purpose of the study was to compare the satisfaction level of the patients provided with both conventional and relined mandibular dentures. Materials and Methods: The study was conducted on fifteen edentulous patients. Each patient was provided with one maxillary and two mandibular complete dentures i.e. one conventional and another relined with long term silicone-based resilient liner (Molloplast-B). Patients’ general satisfaction with the two mandibular dentures was evaluated using questionnaire. The data so collected was compared and analyzed statistically. Results: The overall analysis of the results obtained from the study suggested that the use of soft liners may promote a more satisfying life for edentulous patients. There was an improvement in patients’ general satisfaction rating, ability to chew &speak, fit and comfort with relined mandibular dentures as compared to conventional acrylic resin mandibular dentures opposed by conventional maxillary dentures and the majority of patients had a preference for the relined mandibular dentures.

Clinical outcomes and costs of conventional and digital complete dentures in a university clinic: A retrospective study

Statement of problemScientific data analyzing the clinical outcomes and costs of complete dentures fabricated by using conventional and computer-aided design and computer-aided manufacturing (CAD-CAM) processes are lacking. PurposeThe purpose of this retrospective study was to compare the treatment duration, financial costs, and postdelivery adjustments of CAD-CAM and conventional removable complete dentures. Material and methodsThirty-two edentulous participants (16 women, 16 men; age 35-85 years) who had received either CAD-CAM (n=16) or conventional (n=16) maxillary and mandibular removable complete dentures provided by prosthodontists with a minimum of 2 years of experience were evaluated. The CAD-CAM denture systems were either DDS-AV (AvaDent Digital Dental Solutions) (n=11) or DD-IV (Wieland Digital Denture) (n=5). The total treatment period (days) was recorded at 3 different time points (T0: preliminary alginate impression; T1: denture delivery; T2: last scheduled postdelivery adjustment). Adjustments during the follow-up (after T2) were noted and included the removal of areas of excessive pressure, relining, or repairs. The costs of the dental treatment and the laboratory fees were calculated. The Wilcoxon rank sum tests were used for statistical analysis (α=.05). ResultsNo statistically significant difference regarding the treatment duration between digitally and conventionally fabricated removable complete dentures was found: T0-T1 (P=.889); T1-T2 (P=.675); T2- T3 (P=.978). No significant difference was found in the number adjustments for areas of excessive pressure, relines, or repairs (P=.757, P=1.000, P=1.000) during the period. Laboratory costs of CAD-CAM removable complete dentures were significantly lower than those of conventional removable complete dentures (P<.001), but clinical fees were similar between groups (P=.596), resulting in a reduction in the overall total costs for the CAD-CAM removable complete dentures (P=.011). Regarding the number of clinical visits, neither the group (conventional/CAD-CAM (P=.945)/DDS-AV/DD-IV [P=.848]) nor the interaction group (conventional/CAD-CAM and DDS-AV/DD-IV)/period (P=.084/P=.171) showed any significant differences. ConclusionsCAD-CAM removable complete dentures can be considered a viable alternative to conventional removable complete dentures regarding treatment duration, clinical and follow-up visits, adjustments, and maintenance requirements.

Effect of the Features of Mandibular Implant Overdenture Attachments on the Bending Strain Around Implants

To examine the effect of the attachment features (abutment height, retention, and freedom of rotation) of implant overdentures on the bending strain around implants under an overdenture. Mandibular and maxillary edentulous models were fabricated and covered with silicone rubber. Strain gauges were attached to the four sides of each implant. Two implants (tissue-level implant, 4.1-mm diameter, 10-mm length) were placed bilaterally in the area between the mandibular canines and lateral incisors. A maxillary conventional denture and a mandibular overdenture were made to fit the edentulous models. Three levels of peri-implant bone resorption were created sequentially: no bone resorption, 0.8 mm, and 1.5 mm. Three kinds of attachments (magnetic, stud, and ball attachments) were used. Bending strains generated from a 98-N occlusal load through the maxillary denture were measured using a sensor interface, and the data were analyzed using the Kruskal-Wallis and Bonferroni tests. Multiple regression analysis was used to find the relationship between independent variables (peri-implant bone resorption level, abutment height, retention, and freedom of rotation) and the dependent variable (bending strain). For all attachment types, the bending strains were smallest with no bone resorption and largest with 1.5-mm bone resorption (P < .05). Multiple regression analysis showed that abutment height had the greatest impact on the reduction of bending strain (beta = .413), followed by freedom of rotation (beta = -.349), and retention (beta = .107). Low abutment height, large freedom of rotation, and low retention can minimize bending strain around implants.

Effect of different mini implants distribution for mandibular overdenture cases on maxillary ridge height. retrospective radiographic study

Purpose. The purpose of the study is to evaluate the maxillary ridge change under complete dentures opposed by mandibular overdentures assisted by four mini-implants, in case of inter-foraminal distribution or in case of wide distribution after wearing dentures for 6 years. Methods and material. The subjects enrolled for this study (n = 20). They were treated with maxillary complete dentures, randomly assigned into two equal groups: group І received mandibular overdenture assisted by four mini implants distributed equally in the inter-foraminal region exposed to immediate loading protocol. Group II received mandibular overdenture assisted by four mini-implants (two inserted in canine region and two inserted in first molar region) exposed to immediate loading protocol. Radiographic evaluation of maxillary bone height using digital panorama for every patient of both groups recorded at the time of mini-implants insertion and after 6 years. Results: The results showed non- significant differences using independent t-test between wide & inter-foraminal distribution groups for midline, premaxilla. While, for maxillary tuberosity, the results give significant difference between wide & inter-foraminal distributions at significant levels P Conclusion: the combination syndrome also may occur in conventional maxillary dentures opposed by mini implants assisted mandibular overdentures and wide mini implants distribution has similar effect as inter-foraminal distribution in the maxillary alveolar ridge resorption.

Mandibular two-implant overdentures with CAD-CAM milled bars with distal extensions or retentive anchors: A randomized controlled trial.

This randomized controlled trial (RCT) aimed to demonstrate the non-inferiority of mandibular 2-implant overdentures (IODs) on a CAD-CAM milled bar with long distal extensions (MBDE) against IODs on retentive anchors (RA). Forty edentulous participants rehabilitated with a maxillary conventional denture and a mandibular 2-IOD participated in this trial. They were randomized into two groups [Control group (CG): RA+gold matrices; Experimental group (EG): MBDE+gold clip]. The outcomes included implant survival rate (ISR), chewing efficiency [quantitative (VoH) and subjective (SA) assessments], peri-implant marginal bone levels (PI-MBL), maximum bite force (MBF), and patient-reported outcomes [oral health impact profile (OHIP-EDENT), and denture satisfaction index (DSI)]. Outcomes were recorded at baseline (BL), two weeks (T0 ), 6months (T1 ), and at 1year (T2 ) after the intervention. Intra- and inter-group analyses were performed using regression models with ⍺=0.05. 38 participants completed the T2 visit (CG: n=19, age=74.7±7.8years; EG: n=19, age=70.3±10.7years). At T2 , there was no implant loss in either of the groups (ISR=100%). There were no significant differences between the groups for the PI-MBL changes (p=.754). Improvements occurred faster in the EG than in the CG, but over the observation time, there were no differences between the trial groups for VoH, MBF, OHIP-EDENT, and the DSI, except for SA being significantly better in the EG group (p=.022). The results of this RCT confirm that mandibular 2-IODs with a CAD-CAM milled bar with long distal extensions are not an inferior treatment to the conventional IODs on retentive anchors in the short term (1year).

Oral Health Related Quality of Life of Patients Using Conventional Dentures versus Implant-Supported Overdentures.

Objectives:This study aimed to compare the oral health related quality of life (OHRQoL) of patients using conventional dentures versus implant-supported overdentures.Materials and Methods:This study evaluated the OHRQoL of 90 patients between 35 to 75 years who were selected from several public and private dental clinics in Tehran in 2018. Of all, 45 had conventional dentures of both jaws, and 45 had a mandibular overdenture supported by two implants at the site of mandibular canine teeth and a conventional maxillary denture. The OHRQoL of patients was determined using the Oral Health Impact Prfile-20 (OHIP-20). The questionnaire was translated to Persian, and its content validity and internal consistency were confirmed. Data were analyzed by one-way ANOVA, Mann-Whitney test, and independent t-test.Results:In the conventional denture group, 46.7% had good, 46.7% had moderate, and 6.6% had poor OHRQoL. These values were 55.6%, 37.8% and 6.6% in the overdenture group, respectively. Level of education had a significant correlation with the total score of OHIP-20 in both groups (P<0.05). But no significant association was noted between the residential status and gender of patients with different domains of OHRQoL (P>0.05) except for the psychological disability domain, which had a higher mean value in males with conventional dentures (P<0.05).Conclusion:Patients with a mandibular overdenture supported by two implants at the site of canine teeth and a conventional maxillary denture had higher OHRQoL than patients with conventional dentures of both jaws.

Maxillary Bone Resorption with Conventional Dentures and Four-Implant–Supported Fixed Prosthesis Opposed by Distal-Extension Partial Dentures: A Preliminary 5-year Retrospective Study

The aim of this preliminary study was to evaluate maxillary bone resorption with conventional dentures and implant-supported prostheses opposed by distal-extension removable partial dentures (RPDs). Fifteen patients (seven women and eight men) with totally edentulous maxillary ridges and partially edentulous mandibular ridges (Class I Kennedy classification) received maxillary fixed prostheses on four implants and mandibular distal-extension RPDs (study group). The control group consisted of 15 patients who received conventional maxillary dentures and distal-extension mandibular RPDs without any implant treatment but were matched to the study group and acted as a historical group. Evaluation of vertical maxillary bone resorption for both groups was made at the time of prosthesis insertion (T0) and 5 years later (T2) using the proportional area measurements made on digital panoramic radiographs for anterior and posterior areas. The control group showed significantly higher vertical bone loss than the test group (P < .001). The control group had 0.270 higher maxillary bone loss than the test group. For both groups, anterior maxillary areas showed significantly higher bone loss than posterior areas (P < .003). Anterior maxillary areas had 0.122 higher bone loss compared with posterior areas. Women had 0.035 higher maxillary bone loss compared with men. Within the limitations of this study, implant-supported fixed prostheses for the edentulous maxilla opposed by remaining mandibular anterior teeth reduce maxillary anterior and posterior alveolar bone loss compared with conventional dentures. However, they do not prevent maxillary bone loss.

Comparison between Retention of Maxillary Acrylic and Nylon Denture Base Materials

Loss of teeth is a matter of great concern to majority of the people and their replacement by artificial substitutes, such as dentures, is vital to the continuance of normal life. One of the factors influence patient responses regarding their complete dentures is the quality of retention. Complete denture base is composed of heat polymerized polymethylemethacrylate (PMMA). However, this material presents limitations, particularly in terms of flexural and impact strength and patients representing allergic reaction to PMMA. Nylon denture base material could be useful alternative to PMMA, especially in the patient shows allergy to PMMA. This study was conducted to estimate the difference between retention of conventional acrylic and Valplast maxillary denture base. Ten edentulous patients (five males and five females) with an age range of 45–60 years. For each patient two maxillary dentures were constructed, one from acrylic resin and other from Valplast denture base materials. Specially designed strain gauge–measuring device was used to measure the force required to dislodge the two dentures from basal seats. Six measurements of retention of newly inserted denture base were recorded for each patient (three for maxillary acrylic denture base and three for maxillary nylon denture base). Using paired t-test, a significant improvement in retention obtained by nylon denture base materials in comparison with conventional maxillary acrylic denture base, for both male and female. The retention force that obtained for each patient does not represent the quality of retention for that patient, because we measured the retention at static state and the measurements for each patient were done at same visit of insertion.

Bar versus Locator attachments for maxillary implant overdentures opposed by implant supported mandibular overdentures. Clinical and radiographic evaluation

Purpose: The aim of this short-term clinical trial was to evaluate clinical and radiographic outcomes of Bar and Locator attachments used to retain maxillary implant overdentures opposed by implant supported mandibular overdentures. Material and methods: Ten patients wearing conventional maxillary denture and implant supported mandibular overdentures received 4 implants in the maxillary arch using 2 stage surgical approach. Six months later maxillary overdentures were connected to the implants with locator (group 1) or bar (group 2) attachments. Plaque index, bleeding index, probing depth, implant stability, and marginal bone loss (using Cone beam computerized tomography) were evaluated at time of overdenture delivery, 6 months and 12 months later. Results: Plaque and gingival indices increased significantly with time in bar group only. Bar overdentures recorded significant higher plaque and gingival scores than locator overdentures. No significant difference in pocket depth and implant stability was noted between time intervals or groups. Total marginal bone loss for locator group was significantly higher than bar group after 6 and 12 months. For both groups, marginal bone loss around canine implants was significantly higher than bone loss around premolar implantsConclusion: Within the limits of this study, it could be concluded that both locator and bar retained maxillary overdentures are successful treatment options for patients complaining from instability of maxillary dentures opposed by implant retained mandibular denture. However, locator attachments are advantageous in terms of peri-implant soft tissue health and bar attachments are advantageous regarding peri-implant alveolar bone preservation.

Retention force of zirconia bar retained implant overdenture: Clinical comparative study between PEEK and plastic clips.

Aim: This study aimed to evaluate and compare retention force of two implants retained mandibular overdenture with zirconia bar using two different clip materials.&#x0D; Methodology: 20 completely edentulous patients (8 women and 12 men) with age ranged between 45 and 65 years were selected for this study. All patients received conventional maxillary and mandibular complete dentures. Two implants were inserted bilaterally in the mandibular canine region. CAD-CAM fabricated zirconia bar attachment was used to retain mandibular overdentures. Patients were randomly divided into two equal groups where poly-oxy-methylene (POM) clip was used for Group I and poly-ether-ether-ketone (PEEK) clip for Group II. Retention force was measured at time of overdenture insertion (T0), six months (T6), and twelve months (T12) later.&#x0D; Results: significant difference was recorded between the two groups in initial retention forces (T0) where PEEK clip group recorded higher retention forces in comparison to POM clip group (P=0.029). However, insignificant difference was observed at (T6) and (T12). Within group comparison of mean retention values at different follow-up periods revealed significant difference for both groups.&#x0D; Conclusion:&#x0D; Within parameters of this study, it could be concluded that both POM and PEEK retentive clips can provide comparable retention forces when used with zirconia bar during 12 months period of overdenture use.&#x0D; &#x0D; How to cite this article: Emera RMK, Altonbary GY. Retention force of zirconia bar retained implant overdenture: Clinical comparative study between PEEK and plastic clips. Int Dent Res 2019;9(3):92-8.&#x0D; &#x0D; Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

Comparative study of bone height changes around immediately loaded porous tantalum parallel sided Trabecular &amp; Screw shaped implants retaining mandibular implant- overdentures using CBCT (RCT)

Objective: This study was conducted to evaluate the crestal bone height changes of immediately loaded Porous trabecular tantalum dental implants (PTTM ) and screw shaped titanium implants in mandibular two implant overdenture with CBCT scan. Subjects & Methods: Fourteen completely edentulous patients were rehabilitated with maxillary complete dentures & immediately loaded mandibular two implant overdentures. Patients were selected according to certain inclusion & exclusion criteria. Conventional maxillary & mandibular complete dentures were constructed for all patients. Patients were then randomly divided into two equal groups according to the implant type. Group (I-Intervention Group): TM implants & Group (II- control Group): Conventional titanium Screw implants were utilized. Implants were installed in the mandibular interforaminal region. Implants were immediately loaded with ball retained overdentures. Radiographic Evaluation of crestal bone height changes around the implants was made with CBCT scan; at the denture insertion visit, 6, 12 , & 24 months after denture insertion. Data were collected, tabulated & statistically analyzed. Results: All patients were satisfied with their implant overdentures, No implant loss were recorded during the follow-up Period. The results of this study had revealed that the crestal bone height gradually decreased throughout the study period in the two studied groups. The mean values of crestal bone loss were (0.497mm± 0.161, 0.362mm ±0.045, 0.120mm.±0.13, 0.9 mm±0.67) and (0.65mm± 0.076 , 0.338mm±0. 047, 0.75 ±0.407, 1.20 ±0.108) in group I & Group II respectively at 0-6 month, 6- 12 month, 12- 18 month and from 0-24 month intervals. On comparing the studied Groups: The crestal bone loss was greater in Group (II) than Group (I) along the whole follow-up intervals. In the 1st & 2nd follow -up intervals; (0-6month & 6-12 Months) bone loss was greater in Group (II) than Group- I with statistically insignificant difference (P-values 0.069 ns &0.400 ns respectively). However, in the 3rd interval (6-12months) & (12-18 months) and( 0-24months), bone loss was significantly higher in Group-II than Group-I; with (P=0.000*). Conclusions: Within the limitation of the current study: Trabecular Tantalum Dental Implants (PTTM) may induce less crestal bone loss than conventional screw-shaped titanium implants in immediately loaded mandibular implant overdentures.

Mandibular implant-supported overdentures in (frail) elderly: A prospective study with 20-year follow-up.

PurposeTo prospectively assess long‐term (20 year) clinical, radiographic, and patient‐reported outcomes of an elderly population provided with mandibular implant‐supported overdentures.Materials and MethodsA total of 53 elderly (aged ≥60 years at the time of treatment) were provided with two endosseous implants supporting a mandibular overdenture and a conventional maxillary denture. Outcome parameters—including implant loss, plaque index, gingival index, bleeding index, presence of calculus, probing depth, and satisfaction with implant‐supported overdenture—were scored 1, 5, 10, and 20 years after prosthetic treatment. Radiographic analysis was performed to assess peri‐implant bone changes. At the 20‐year evaluation, frailty (Groningen Frailty Index) and quality of life (EuroQol 5D) were additionally assessed.ResultsA total of 15 patients completed the 20‐year follow‐up. The 20‐year implant survival rate was 92.5%. Plaque index, bleeding index, and probing depth increased slightly over time, while gingival index and presence of calculus remained unchanged. Radiographic analysis revealed minor marginal bone loss during the first 10 years and no further loss thereafter. Participants were very satisfied with their prosthesis and reported a good quality of life. At the 20‐year evaluation, 64.3% of the patients were classified as frail.ConclusionsThe long‐term survival of implants supporting a mandibular overdenture is high. Although most elderly in the study became frail over time, peri‐implant health and marginal bone level remained at a satisfactory level.

The influence of bone loss on peri-implant bending strain under overdentures.

The purpose of this study was to evaluate the biomechanical effects of bone loss on peri-implant bending strain underneath overdentures. One mandibular and one maxillary edentulous model were created and covered with 2 to 4 mm of silicone rubber to simulate the oral mucosa. Four strain gauges were attached to four sides of each implant. In the mandibular model, two implants were inserted, and the implant was placed bilaterally in the area between the mandibular canines and lateral incisors. A maxillary conventional denture and mandibular overdenture were fabricated with acrylic resin to fit the edentulous models. Five bone loss levels were created: no bone loss, 0.8 mm bone loss on only the left implant, 0.8 mm bone loss bilaterally, 1.5 mm bone loss on only the left implant, and 1.5 mm bone loss bilaterally. Magnetic attachments were used to retain the denture. The bending strains generated from three types of unilateral loading were measured by a sensor interface, and the data were analyzed using the Kruskal-Wallis test and Bonferroni's post hoc test. Bending strain increased with decreasing bone levels on the loading side. On the nonloading side, bending strains were greater at even bone loss (0.8 mm or 1.5 mm bone loss bilaterally) than at uneven bone loss (0.8 mm or 1.5 mm bone loss on only the left implant). Strains under loading at the left first premolar were approximately equal to that under loading with a cotton roll; these strains were higher than those generated with loading at the left first molar. Peri-implant bending strains rapidly increased on the loading side as bone loss levels increased. Peri-implant bending strains on the nonloading side were higher at bilaterally even bone loss than at unilateral bone loss.