Two-center clinical trial of implant–retained mandibular overdentures versus complete dentures – chewing ability

Abstract This study is a two-center clinical trial with the aim to assess the treatment effects of implant-retained mandibular overdentures versus conventional complete dentures. Treatment had been assigned according to a balanced allocation method. The following criteria were used to enhance the comparability of the treatment groups: age, gender, the edentulous period of the mandible, the number of previously made mandibular dentures, the number of years having worn the present mandibular denture and the symphyseal bone height. 151 patients with severely resorbed mandibles participated in the study, they were treated at two centers. Ninety-one patients received an implant-retained mandibular overdenture (IRO) and 60 patients a conventional complete denture (CD). Since some patients refused the allocated treatment the “Intention To Treat” principle was applied. This implies that patients are evaluated in the originally allocated treatment group regardless of the actual treatment they received. Patient's experiences were evaluated before treatment and I yr after insertion of the new dentures. Results before treatment showed that both treatment groups were comparable: they were dissatisfied with their mandibular denture and they could hardly chew tough or hard foods. One year after insertion of the new dentures the IRO-group was satisfied with their mandibular denture, whereas only one third of the CD-group was satisfied. With respect to the chewing ability the IRO-group scored significantly better than the CD-group (P0.0001).     

The effect of different mandibular dentures on antagonistic maxillary ridge

PURPOSE: Is to evaluate the antagonistic, maxillary ridge resorption for different prosthetic modalities mainly mucosa-supported mandibular complete overdentures, combined mucosa implant-supported mandibular complete overdenture, and lower conventional complete dentures. MATERIALS AND METHODS: Fifteen completely edentulous patients were divided into 3 groups; 5 patients each. Group I patients received maxillary conventional denture and mandibular overdentures retained by magnet attachment on 2 implants (mainly mucosa-supported overdenture). Group II patients received maxillary conventional denture and mandibular overdentures retained by bar attachment on 2 implants (combined mucosa implant-supported overdenture). Group III patients received upper and lower conventional complete denture. All patients were evaluated clinically and radiographically immediately after insertion and after 1 and 2 years. Panoramic radiographic film was used to evaluate the antagonistic maxillary ridge resorption. RESULTS: Indicated a more pronounced annual bone resorption of the antagonistic maxillary ridge after 2 years in patients with conventional complete denture wearers when compared with patients with combined mucosa implant-supported mandibular complete overdenture and mainly mucosa-supported mandibular complete overdenture groups. CONCLUSION: Using a combined mucosa implant-supported mandibular complete overdenture the amount of antagonistic maxillary alveolar bone resorption increases when compared with the mainly mucosa-supported complete overdenture.     

A randomized controlled trial of implant-retained mandibular overdentures

Evidence from randomized clinical trials of implant-retained overdentures is very limited at the present time. The aim of this study was to compare implant-retained mandibular overdentures and conventional complete dentures in a randomized controlled trial (RCT). Our a priori hypothesis was that implant-retained mandibular overdentures would be significantly better than conventional complete dentures. Edentulous patients (n = 118) were randomly allocated to either an Implant Group (n = 62) or a Denture Group (n = 56). Patients completed the Oral Health Impact Profile (OHIP) and a denture satisfaction scale pre-treatment and three months post-treatment. Upon completion of treatment, both groups reported improvement (p < 0.001, Wilcoxon Ranks Sum test) in oral-health-related quality of life and denture satisfaction. There were no significant post-treatment differences between the groups, but a treatment effect may be masked by application of "intention to treat" analysis. The OHIP change scores were significantly greater for patients receiving implants than for those who refused them.     

Psychologic response of the edentulous patient after primary surgery for oral cancer: A cross-sectional study.

STATEMENT OF PROBLEM: Edentulous patients can have difficulty in tolerating dentures and this may lead to psychologic disturbance. The problem is potentially more severe for edentulous patients after primary surgery for oral cancer, where treatment can include composite resection and reconstruction, followed by adjuvant radiotherapy. PURPOSE: This study investigated the psychologic response and oral satisfaction of edentulous patients treated by surgery for oral squamous cell carcinoma, and to make a comparison to edentulous noncancer counterparts. METHODS AND MATERIAL: The cross-sectional study included patients who were alive and disease-free 2 to 3 years after primary surgery. Seventy patients underwent surgery at the Regional Maxillofacial Unit, Liverpool, in 1993 and 1994. Twenty-eight patients were disease-free; 26 completed questionnaires that included a general health questionnaire (GHQ), a body satisfaction scale, a self-esteem scale, an oral symptom checklist, and a denture satisfaction questionnaire. Comparison was made with 98 noncancer edentulous patients from the same unit. RESULTS: There were similarities in psychologic and oral satisfaction scores between the noncancer and cancer edentulous patients. Cancer patients reported lower self-esteem (P <.02). Cancer patients who were not rehabilitated with either conventional or implant-retained prostheses had significant psychologic morbidity as measured by the GHQ, self-esteem, and body satisfaction scales. Cancer patients with implant-retained overdentures reported greater satisfaction with their dentures compared with their counterparts who wore conventional dentures (P <.05). CONCLUSION: Edentulous cancer patients who do not achieve oral rehabilitation after surgery for oral cancer exhibited significant psychologic morbidity. Patients with implant-retained overdentures exhibited a tendency to adopt the same psychologic response with improved denture satisfaction as edentulous patients with conventional dentures, despite the former having more extensive disease that would otherwise make the provision of dentures much more difficult if implants were not used.     

Maxillary anterior and mandibular posterior residual ridge resorption in patients wearing a mandibular implant-retained overdenture

The mandibular implant-retained overdenture could improve masticatory function compared to the conventional complete denture. However, increased forces exerted by the overdenture could increase residual ridge resorption of the maxillary anterior and mandibular posterior areas. The aim of this study was to compare the effect of the mandibular implant-retained overdenture using two or four dental implants, or the conventional complete denture on resorption of the residual ridge of the maxillary anterior and mandibular posterior areas over a period of 10 years. In total, 120 patients, 30 patients treated with an overdenture on two implants (two-implant group), 30 patients with an overdenture on four implants (four-implant group) and 60 patients treated with a conventional full denture (conventional group), participated in this study. On panoramic radiographs, made before and 10 years after treatment, proportional area measurements were applied to determine changes in bone height. After 10 years, a statistically significant amount of bone resorption had occurred in the anterior maxilla in the two-implant group and in the four-implant group. A significant amount of bone resorption had occurred in the posterior mandible in all three groups. There were no statistically significant differences between the groups in both areas. Patients presented large individual differences. It is concluded that patients rehabilitated with implant-retained mandibular overdentures are not subjected to more residual ridge resorption in the anterior maxilla when compared to patients wearing a conventional full denture. Regarding the mandibular posterior residual ridge, resorption was irrespective of wearing an implant-retained mandibular overdenture or a conventional mandibular denture.     

A randomized clinical trial comparing the efficacy of mandibular implant-supported overdentures and conventional dentures in diabetic patients. Part II. Comparisons of masticatory performance

Statement of problem. Convincing evidence is lacking to demonstrate the functional superiority of mandibular implant-supported overdentures over conventional dentures.Purpose. This randomized clinical trial was conducted to compare masticatory functional effectiveness of mandibular implant-supported overdentures and conventional dentures in diabetic denture wearers with clinically acceptable metabolic control.Methods. A total of 102 edentulous diabetic patients, treated with or without insulin, were randomized to receive a new maxillary and either a mandibular conventional denture or an implant-supported overdenture. Treatment was completed in 89 patients, 37 with conventional dentures and 52 with Hader bar-clip attachment overdentures supported by two IMZ implants. Besides data from medical and dental histories, oromaxillofacial examinations, and questionnaires, masticatory tests were performed by patients before and at 6 and 24 months after treatment completion. Although 78 patients (28 in the conventional, 50 in the overdenture group) performed tests at 6 months after treatment, 68 (25 in the conventional, 43 in the overdenture) had performance data for both entry and 6-month posttreatment intervals.Results. The two treatment groups were highly comparable in terms of general characteristics, quality of original dentures, tissue support, and past denture experience. No significant differences were found between patients treated for diabetes with or without insulin. All four masticatory performance scores with original dentures were higher in the conventional denture group than the overdenture group. The posttreatment performance scores for the two treatment groups became similar because of the higher gains in the overdenture group. Patients with low initial performance scores showed greater posttreatment gains with both conventional dentures and overdentures.Conclusions. The implant-supported overdenture showed no significant advantage over the conventional denture for improving the ability to comminute food in this group of diabetic patients with higher than average initial functional levels observed for other groups of denture wearers in previous studies. (J Prosthet Dent 1998;79:632-40.)     

Clinical and radiographic evaluation of implant-retained mandibular overdentures with immediate loading

PURPOSE: The aim of this study was to evaluate and compare immediate-loaded implant-retained mandibular overdentures and delayed-loaded implant-retained mandibular overdentures. MATERIALS: Ten completely edentulous male patients received 40 dental implants. Patients were randomly divided into 2 equal groups, 5 patients each. Patients of both groups received conventional maxillary complete denture and had stage 1 surgery for placing 4 dental implant fixtures, 2 on each side anterior to the mental foramina. Group A: One-stage surgical procedure and immediate loading. Patients in this group received mandibular bar-retained overdenture supported by 4 endosseous implants loaded immediately after implant placement. Group B: The original 2-stage concept and delayed loading. Patients in this group received mandibular bar-retained overdenture supported by 4 endosseous implants that remained submerged for a period of 4 months before loading. The patients were evaluated clinically and radiographically immediately after overdenture delivery and after 6 months, 12 months, 18 months, and 24 months. RESULTS: The results of clinical evaluation showed no statistical significant difference between the 2 groups regarding the effect of treatment. The radiographic assessment showed no statistical significant difference in mesial and distal alveolar bone loss at the different intervals of the follow-up period, except at the 12-month period, where immediately loaded implants showed a decrease in the amount of alveolar bone loss mesially and distally compared to delayed loaded implants. CONCLUSIONS: The results suggest that immediate-loaded implants provide promising results compared to delayed-loaded implants and can be a possible alternative procedure in implant dentistry.     

Changes in the edentulous maxilla in persons wearing implant-retained mandibular overdentures

STATEMENT OF PROBLEM: It has been suggested that risk for severe resorption in the anterior maxilla is increased in persons wearing mandibular implant-retained overdentures. However, little information is available about the changes in the edentulous maxilla after mandibular implant treatment. PURPOSE: This study determined the possible changes in the width of the maxillary residual ridge 6 years after receiving mandibular implant-supported or implant-mucosa-supported overdentures and evaluated the association between the anatomic changes and subjective complaints with maxillary complete dentures. METHODS AND MATERIAL: The subjects for this study (n = 55), enrolled among the participants of a prospective clinical trial, were randomly assigned into 3 groups treated with: (a) implant-supported overdentures on a transmandibular implant system (n = 21); (b) implant-mucosa-supported overdentures on 2 IMZ implants (n = 20); or (c) conventional complete dentures (n = 14). A lingual contact occlusion concept with anterior open bite was used for tooth arrangement in all subjects. Diagnostic casts were made at baseline, and again at the 6-year follow-up. Most prominent points perpendicular to the crest of residual ridge were located in the incisor, canine, and premolar regions, after which the width of the ridge was recorded at these points with a Boley gage. Subjects' opinions on their dentures were evaluated with a questionnaire. RESULTS: Significant reduction in the width of the ridge was found in all measurement areas (mean difference = 0.4 to 0.6 mm; P <.0001). However, changes were small and not associated with the type of prosthetic restoration in the mandible. In subjects with implant-mucosa-supported overdentures, complaint of loose maxillary denture correlated with the decrement of residual ridge width. CONCLUSION: The width of residual ridge decreases with time, despite the type of mandibular prosthetic restoration.     

Patient expectations of oral implant-retained prostheses in a UK dental hospital

STATEMENT OF PROBLEM: The loss of the natural dentition leads to severe functional impairment in many edentulous adults. A prosthesis retained and supported by osseointegrated dental implants may provide a satisfactory solution for people who have lost all their natural teeth. However, little information is available as to what patients requesting implants expect of implant-retained prostheses. AIM: The aim of this study was to assess the expectations of a group of edentulous patients requesting implant therapy. METHOD: The study included two groups: (1) a group of edentulous adults who requested implant therapy ('implant group'); and (2) an edentulous control group, of similar age and gender distribution as the implant group, receiving conventional complete dentures. Following a clinical and radiographic examination of the patients, data were collected using validated questionnaires. Both groups made a subjective assessment of current dentures. The implant group also completed a questionnaire which assessed expectations of implant-retained prostheses. RESULTS: Baseline satisfaction with current dentures was low in both groups, with the implant group being significantly less satisfied with comfort and stability of their mandibular dentures. Perceived ability of the implant group to chew hard foods was less than the control group. The implant group's expectations of an implant-retained prosthesis were significantly greater than for a conventional denture. CONCLUSION: Careful assessment of patient expectation of implant therapy is essential to determine appropriate treatment need, and to highlight unrealistic expectations.     

Effectiveness of three treatment modalities for the edentulous mandible. A five-year randomized clinical trial

Currently, 3 treatment options are available for patients with denture complaints and an edentulous mandible with a height of at least 15 mm: meticulous construction of a new set of dentures (CD), construction of a new set of dentures following preprosthetic surgery to enlarge the denture-bearing area (PPS), and construction of an implant-retained mandibular overdenture (IRO). The aim of this study was to evaluate patient satisfaction and subjective chewing ability of edentulous patients treated with one of these treatment modalities. Ninety edentulous patients (Cawood class IV and V, mean mandibular height 20.7 mm) were randomly assigned to receive 1 of these 3 groups. Denture satisfaction and chewing ability were assessed using questionnaires focusing on denture-related complaints and problems chewing different types of food were assessed before treatment, and 1- and 5-years after treatment. At the 1-year evaluation, significantly better scores were observed in the 2 surgical groups (IRO, PPS) than in the CD group. At 5-year evaluation the "complaints of the lower denture" showed a significantly better score in the IRO group when compared to the PPS and CD groups. No significant differences were observed between the PPS and CD group. From this study it is concluded that both in the short and long term denture satisfaction appears most favourable in the IRO group when compared to the PPS and CD groups. Implant-retained overdentures are therefore a satisfactory treatment modality for edentulous patients with problems with their lower denture, even in cases of not severely resorbed mandibles.     

Does a prosthodontist spend more time providing mandibular two-implant overdentures than conventional dentures?

PURPOSE: In this article, the time taken by a prosthodontist to fabricate and maintain mandibular overdentures retained by two implants and conventional dentures is compared. MATERIALS AND METHODS: Sixty edentulous patients between the ages of 65 and 75 completed a randomized clinical trial. All received new maxillary conventional dentures and either a mandibular conventional denture (n = 30) or a two-implant overdenture on ball attachments (n = 30). The time spent by the prosthodontist and the number of visits required for treatment, including both scheduled and unscheduled visits, were recorded for each patient from preliminary impressions to 6 months following delivery. Data from the two groups were compared using Mann-Whitney U tests. RESULTS: The prosthodontist spent a mean total time of 296 minutes in treating an implant overdenture patient and 282 minutes on a conventional denture patient during the period from preliminary impressions to the 6-month follow-up. The mean numbers of appointments were 10.1 (implant group) and 10.8 (conventional group). These differences were not significant. CONCLUSION: Although additional knowledge is required to treat patients with implant prostheses, the time required by the prosthodontist to provide two-implant mandibular overdentures with ball attachments was not significantly different than the time needed for conventional denture treatment.     

Masticatory performance with mandibular implant-retained overdentures

It was investigated in a clinical trial whether the masticatory performance of complete-denture wearers depended on the support for their mandibular dentures by implants or mucosa. The trial involved the provision of a new maxillary denture and either a new conventional mandibular denture (mucosa-borne), a mandibular overdenture retained by two IMZ-implants (implant-mucosa-borne), or a mandibular overdenture on a transmandibular implant (TMI; mainly implant-borne). In comparison with mandibular implant-retained overdentures, subjects with conventional dentures needed 1.5 to 3.6 times more chewing strokes for an equivalent reduction in particle size. No differences in masticatory performance were found between subjects with IMZ-implants and those with TMI. This suggests that the increased stability of the mandibular denture with implants determines the wearer's masticatory performance, rather than the support by implants.     

Assessment of states of dentures and interest in implant-retained prosthetic treatment in 55-year-old edentulous Finns

Abstract – One hundred and fifty 55-year-old edentulous subjects (104 women and 46 men) were interviewed. Materials, conditions, functional stabilities, and occlusions of complete dentures, and resorption of alveolar crests were recorded and assessed. The dentures were in good condition in 52% of subjects. Occlusion was correct in 45% of cases. Every fifth mandibular denture exhibited good functional stability. The mean age of dentures in good condition and functionally stable was statistically significantly lower than the mean age of dentures poor in these respects. Severe alveolar resorption contributed to poor functional stability of dentures ( P = 0.0068 (maxilla), P = 0.0023 (mandible)) and to incorrect occlusion ( P =0.0177). Good agreement was noted between objective and subjective opinions of denture function ( p = 0.01 (maxillary denture), P = 0.01 (mandibular denture)). Although oral rehabilitation with endosseous implants is common and, objectively, needs for such treatment existed, only 22 subjects (15%) who had recently had their dentures renewed and were experiencing problems with functional stability were interested in implant-retained overdentures.     

Relationship between prosthodontic evaluation and patient ratings of mandibular conventional and implant prostheses

PURPOSE: The purpose of this study was to compare clinicians' ratings of the state of oral tissues and their satisfaction with treatment to edentulous patients' ratings of treatment success after provision of mandibular implant overdentures or conventional dentures. MATERIALS AND METHODS: Sixty subjects randomly received either mandibular overdentures retained by two implants (n = 30) or new conventional mandibular complete dentures (n = 30). All were given new conventional maxillary dentures. Baseline measures included clinical evaluation of the oral soft and hard tissues. Patients rated their general satisfaction before and after treatment, as well as their satisfaction with stability, speech, and esthetics on visual analogue scales. The treating prosthodontist rated the dentures for the same categories. Patient and clinician ratings were compared using correlations, t tests, and linear regression. RESULTS: None of the clinical variables were significantly correlated with patient satisfaction before or after treatment. The prosthodontist rated mandibular implant overdentures significantly better than conventional dentures regarding general satisfaction, stability, speech, and esthetics. Implant overdentures were also easier to fabricate (P < .0001). The prosthodontists' scores were not significantly correlated with patient scores for any question. CONCLUSION: Clinicians' assessments of the quality of denture-supporting tissues are poor predictors of patient satisfaction with mandibular implant or conventional prostheses. Prosthodontists and patients both rate mandibular implant overdentures as significantly superior to conventional dentures, but patients and clinicians do not usually agree when evaluating individual prostheses.     

The effect of denture stability on bite force and muscular effort

This study tested the hypothesis that denture instability limits the amount of voluntary muscular effort generated by denture wearers. Seventeen edentulous subjects (seven men, 10 women; mean age 60·3 ± 13·0 years) with newly acquired implant-retained mandibular overdentures and a conventional maxillary denture participated. Maximum bite forces and corresponding electromyographic (EMG) activity from the temporalis and masseter muscles (bilaterally) were recorded under two experimental conditions: (i) Unilateral premolar and molar bites without additional support, and (ii) premolar and molar bites with bite block support on the opposite side. In addition, EMG values alone were recorded during maximum clenching without any transducer between the upper and lower dentures. The level of muscular effort was significantly higher with greater denture support. These results indicate that denture instability probably prevents denture wearers from using the full potential of their jaw muscles, especially during unilateral biting and chewing, even with two implants supporting the mandibular dentures.     

The effectiveness of 2‐implant overdentures – a pragmatic international multicentre study

Summary The purpose of this multicentre observational study was to determine patient satisfaction with either conventional dentures or mandibular 2‐implant overdentures in a ‘real world’ setting. Two hundred and three edentulous patients (mean age 68·8 ± 10·4 years) were recruited at eight centres located in North America, South America and Europe. The patients were provided with new mandibular conventional dentures or implant overdentures supported by two implants and ball attachments. At baseline and at 6 months post‐treatment, they rated their satisfaction with their mandibular prostheses on 100‐mm visual analogue scale questionnaires. One hundred and two (50·2%) participants had valid baseline and 6‐month satisfaction data. Although both groups reported improvements, the implant overdenture group reported significantly higher ratings of overall satisfaction, comfort, stability, ability to speak and ability to chew. These results suggest that edentulous patients who choose mandibular implant overdentures have significantly greater improvements in satisfaction, despite their relatively higher cost, than those who choose new conventional dentures.     

A clinical trial of patient satisfaction and prosthodontic needs with ball and bar attachments for implant-retained complete overdentures: three-year results

STATEMENT OF PROBLEM: Few prospective trials of implant-retained mandibular dentures have evaluated the increase and duration of patient satisfaction, costs of denture maintenance in relation to different methods of attaching overdentures to implants, or the use of a reinforced framework. PURPOSE: This report evaluates subjects' satisfaction and prosthodontic maintenance during a 3-year randomized clinical trial of implant-retained mandibular complete dentures, whether reinforced or not with a cast framework, and attached by bar-clip or 2.25-mm ball-spring matrices to endosteal dental implants. MATERIALS AND METHODS: One hundred edentulous subjects, each having at least 1 year's experience with conventional complete dentures, were selected from respondents to a university dental clinic's request for volunteers. Candidates were examined to verify adequate mandibular bone and medical suitability for implants. Subjects then received 2 implants in the anterior mandible before being stratified by mandibular bone height and gender and assigned randomly to 1 of 4 treatment groups. Every subject received a new maxillary complete denture in addition to an implant-supported mandibular complete denture, with or without a reinforcing framework, connected to implants by either a bar-clip or a ball-spring patrix and matrix. The dentures were adjusted and repaired as needed. Subjects indicated on a visual analogue scale (VAS) satisfaction with conventional dentures prior to the study and then with new dentures at 1 month, 1 year, and 2 years. The results reported here are from the first 68 subjects observed for 3 years after receiving new dentures (19 subjects received new dentures less than 3 years before this analysis, and another 13 subjects were lost to follow-up). VAS scores are presented in simple tables and graphs, and results for different groups were compared using 2-sided nonparametric rank tests and repeated measures ANOVA. With respect to costs and maintenance, t tests were used to compare group means. Sample size and other design considerations used a .05 significance level. RESULTS: After receiving new dentures with mandibular implant supports, improved satisfaction "within subject" was prompt, durable, substantial, and statistically significant, regardless of the attachment mechanism, and with or without a reinforcing framework. In contrast, there were no notable satisfaction differences between the 2 attachment mechanisms, or with the presence or absence of a reinforcing framework, either at specific intervals after receiving the new dentures, or in repeated measures ANOVA. For both attachment groups, most denture adjustments occurred during the first year. This accounted for 81% of total adjustments during 3 years, when the 34 subjects in the ball-spring group and the 34 in the bar-clip group were combined. The mean numbers of adjustments per subject and associated clinical times did not differ significantly between the 2 groups. Conversely, denture repairs declined more slowly than adjustments. Almost all repairs (90%) occurred in the ball-spring group to correct problems with the attachments, 39% in the first year, and tapering off only slightly in the following 2 years. Over 3 years of follow-up, mean numbers of repairs per subject differed significantly between groups: 6.7 repairs per person in the ball-spring group, compared to 0.8 in the bar-clip group ( P<.001), and mean time per appointment was greater for repairs in the ball-spring group: 18.9 minutes compared to 16.9 ( P<.01). The cast framework had no influence on the satisfaction expressed or on adjustments and repairs. CONCLUSION: Subjects were very satisfied with the new dentures, although the ball-spring attachment tested in this trial required substantially more repairs.     

Oral health status and treatment satisfaction with mandibular implant overdentures and conventional dentures: a randomized clinical trial in a senior population

PURPOSE: The purpose of this study was to compare elderly patients' satisfaction and oral health-related quality of life with mandibular two-implant overdentures and conventional dentures. MATERIALS AND METHODS: Sixty edentulous subjects aged 65 to 75 years were randomly assigned to two groups treated with maxillary conventional dentures and either a mandibular conventional denture (n = 30) or an overdenture supported by two implants with ball retainers (n = 30). Subjects rated their general satisfaction, as well as other features of their dentures (comfort, stability, ability to chew, speech, esthetics, and cleaning ability), prior to treatment and 2 months postdelivery. Changes in ratings on the original Oral Health Impact Profile (OHIP) and its short form (OHIP-EDENT) were also used as indicators of oral health-related quality of life. RESULTS: The primary outcome of this study, ratings of general satisfaction 2 months postdelivery, was significantly better in the group treated with mandibular two-implant overdentures (P = .001). In addition, the implant group gave significantly higher ratings on comfort, stability, and ability to chew. Furthermore, using OHIP-EDENT, subjects who received mandibular two-implant overdentures had significantly fewer oral health-related quality of life problems than did the conventional group. CONCLUSION: These short-term results suggest that mandibular two-implant overdentures combined with maxillary conventional dentures provide better function and oral health-related quality of life than conventional dentures.     

Oral and general health-related quality of life with conventional and implant dentures

Implant overdentures and conventional prostheses have been compared in several trials using a variety of functional and oral health-related quality of life (OHQOL) outcomes. In this paper, we describe the impact of implant overdentures on general and OHQOL in seniors. OBJECTIVES: To compare the oral health-related and general quality of life of seniors (aged 65-75 years) who received either mandibular implant overdentures or conventional dentures. METHODS: Sixty edentulous patients were recruited. Thirty received mandibular overdentures retained by two implants (IOD) and a conventional maxillary denture, the other 30 subjects received new maxillary and mandibular conventional complete dentures (CD). All completed the 20-item version of the Oral Health Impact Profile (OHIP-20) before treatment, then at two and 6 months after delivery of the dentures. The SF-36 general health questionnaire was completed at baseline and 6 months only. RESULTS: Pretreatment and 6-month data from 55 subjects were analyzed. Those who received the IODs had significantly better OHIP-20 total scores at 6 months. Results for IOD subjects were also superior in the functional limitation, physical pain, physical disability and psychological disability subscales. While no significant between group difference was found on the SF-36 health survey, significant pre-post-treatment differences within the IOD group were detected for the role emotional, vitality and the social function scales. CONCLUSIONS: Mandibular overdentures retained by two implants provide elderly patients with better OHQOL. General health-related quality of life improved in the implant group.     

全颌固定式种植义齿

目的：牙列缺失的种植义齿修复多采用覆盖义齿方式，但某些患者仍希望得到固定修复。Branemark的可拆卸固定全颌种植义齿技术复杂，美观清洁卫生等也不理想。本研究要建立一种牙列缺失的固定种植我齿修复模式。方法：11例有条件的无牙颌患者，在CDIC种植体支持基础上，用常规烤瓷溶附冠桥技术完全成颌固定式种植义齿修复。结果：1至5年的观察表明，该修复模式在咀嚼功能，美观性，舒适感及清洁卫生维护均获得满意结果。