Masticatory Function with Implant-supported Overdentures

A comparative evaluation of chewing efficiency, masticatory bite force, and patient satisfaction between conventional denture and implant-supported mandibular overdenture: An in vivo study

Purpose:

The purpose of this within-subject crossover clinical trial was to compare and evaluate the chewing efficiency, masticatory bite force, and patient satisfaction with conventional dentures and two implant-retained mandible overdentures after 4 weeks of usage.

Method:

This within-subject crossover clinical trial was carried out in the Department of Prosthodontics in K.D Dental College and Hospital. A total 15 patients were selected for the study. To report the changes in chewing efficiency by chewing 6gms of peanuts with 40 chewing strokes and comparing the particle size of the chewed material between two implant retained mandibular overdenture with that of conventional denture using micro vu excel gantry type visual measurement machine. To report changes in masticatory bite force after transition of conventional complete denture patient to implant retained overdenture after using the prosthesis for four weeks each and recorded by digital transducer. To assess the patient satisfaction after transition of conventional complete denture patient to implant retained mandibular overdenture with help of OHIP edent patient satisfaction questionnaire.

Results:

The chewing efficiency for implant retained overdenture increased significantly than that of conventional denture. The particle size decreased to 76.34% for implant supported overdenture than that of conventional denture. The chewing strokes required by conventional denture was 69 strokes and that by implant supported overdenture which was 40 strokes to get the same mean particle size. The patients satisfaction after receiving the implant retained overdenture was significantly higher than that of complete denture.

Conclusion:

The provision of two mandibular implants significantly improves measures of oral function and better quality of life for edentulous patients.

To what extent residual alveolar ridge can be preserved by implant? A systematic review

Background

It has been reported that the load for (or to) implant-supported restoration may lead to bone remodeling as bone resorption and/or formation. While many authors supported the process of bone resorption, others elaborated bone apposition and increasing bone density close and remote to implant body (or fixture). This may suggest the role of the implant to reserve alveolar ridge from physiologic/pathologic resorption. The aim of this systematic review was to predict to how extend dental implants can preserve the residual alveolar ridge based on previous clinical investigations.

Methods

This systematic review based on the retrospective and prospective studies, randomized clinical trial, and case reports. The process of searching for proposed articles included PubMed, Ovid, and Web of Science databases, with specific inclusion and exclusion criterion.

Results

A total 2139 citations were identified. After expunging the repeated articles between databases and application of exclusion and inclusion criteria, 18 articles were found to meet the topic of this systematic review. Many of the articles reported bone preservation with implant-assisted restorations, and the rest denoted noticeable bone apposition.

Conclusion

According to the published clinical studies, the behavior of bone remodeling around implant predicts a sort of residual alveolar bone preservation.

Impact of mandibular conventional denture and overdenture on quality of life and masticatory efficiency

The aim of this non-randomized controlled clinical trial was to evaluate the oral health-related quality of life and masticatory efficiency of patients rehabilitated with mandibular two-implant overdentures with immediate loading or conventional dentures. Fifty completely edentulous patients wearing bimaxillary conventional dentures, for at least one year, were recruited. The patients were then assigned to either two treatment groups: mandibular overdentures supported by two implants with bar-clip system and a maxillary conventional denture (n = 25), and new maxillary and mandibular conventional complete dentures (n = 25). Masticatory efficiency and oral health-related quality of life were assessed before and 3 months after denture insertion. The Brazilian version of OHIP-Edent questionnaire was used to assess the oral health-related quality of life. Masticatory efficiency was evaluated with chewing capsules through a colorimetric method. The results revealed fewer oral health-related quality of life problems in patients wearing mandibular two-implant overdentures compared to the conventional dentures group. In addition, the implant overdenture group presented statistically significant improvement in masticatory efficiency (p = 0.001). There was no correlation between masticatory efficiency and OHIP in the implant group (p > 0.05), however a correlation was found in the conventional denture group (p < 0.05). Therefore, these short-term results suggest that mandibular overdenture retained by 2 implants with immediate loading combined with maxillary conventional dentures provide better masticatory efficiency and oral health-related quality of life than mandibular conventional dentures.

Changes in biting forces with implant-supported overdenture in the lower jaw: A comparison between conventional and mini implants in a pilot study

The biting ability of patients improves noticeably after receiving implant-supported overdentures in comparison to conventional complete dentures. However, the change of biting with such treatment concepts has been quantitatively investigated in only a limited number of studies. The aim of the present study has been to measure the biting forces of edentulous patients with complete dentures and after receiving implant-supported overdentures. A total of 26 edentulous patients were included. Ten patients received two to four conventional implants (control group, Ø3.3-3.7mm, L11-13mm) and 16 patients received four to five mini implants (study group, Ø1.8-2.4mm, L13-15mm) inserted in the mandibular interforaminal region. All patients received a lower overdenture with ball/rubber ring attachments and a complete denture for the maxilla. The biting forces were measured using Prescale pressure sheets type low before the insertion of implants and after receiving implant-supported overdenture. The measured sheets were later scanned and analysed using FPD-8010E software. The range of biting forces before the insertion of implants was 80N-122N for the control group and 66-88N for the study group. After the insertion of implants, the range of biting forces increased to 167N-235N for the control group and to 81N-138N for the study group. However, the increase in biting forces after the insertion of implants was not significant for either group. No significant difference was obtained between the two implant systems. The biting forces improved after insertion of implants regardless of which implant system was used. However, the degree of improvement is noticeably related to the original bone quality of the mandible at the insertion regions of implants.

Dental implants in the elderly population: a systematic review and meta-analysis

OBJECTIVE

This systematic review was conducted to evaluate the outcome of dental implant therapy in elderly patients (≥65 years).

MATERIAL AND METHODS

Online database and hand searches were systematically performed to identify studies reporting on dental implants placed in the partially/completely edentulous jaws of elderly patients. Only prospective studies reporting on regular-diameter (≥3 mm), micro-rough surface implants were included in this review. Two investigators performed the search and data extraction. An inter-investigator reliability was verified using kappa statistics (κ). A meta-analysis was performed on implant survival rates, while the mean peri-implant marginal bone level changes (PI-MBL), technical/mechanical complications, and biological complications were reported descriptively.

RESULTS

The systematic search yielded 2221 publications, of which 11 studies were included for statistical analyses. The calculated κ for the various parameters extracted was κ = 0.818-1.000. A meta-analysis was performed on the post-loading implant survival rates at 1, 3, 5, and 10 years. The random-effects model revealed an overall 1-year implant survival of 97.7% (95% CI: 95.8, 98.8; I²  = 0.00%, P = 0.968; n = 11 studies). The model further revealed an overall implant survival of 96.3% (95% CI: 92.8, 98.1; I²  = 0.00%, P = 0.618; n = 6 studies), 96.2% (95% CI: 93.0, 97.9; I²  = 0.00%, P = 0.850; n = 7 studies), and 91.2% (95% CI: 83.4, 95.6; I²  = 0.00%, P = 0.381; n = 3 studies) for 3, 5, and 10 years, respectively. The reported 1-year average PI-MBL ranged between 0.1 and 0.3 mm, while the reported 5- and 10-year PI-MBL were 0.7 and 1.5 mm, respectively. Information obtained pertaining to the technical and biological complications in the included studies was inadequate for statistical analysis. The frequent technical/mechanical complications reported were abutment screw loosening, fracture of the overdenture prostheses, activation of retentive clips, ceramic chipping, and fractures. The common biological complication reported included peri-implant mucositis, mucosal enlargement, bone loss, pain, and implant loss.

CONCLUSIONS

This review provides robust evidence favoring dental implant therapy in elderly patients as a predictable long-term treatment option, in terms of implant survival, clinically acceptable PI-MBL changes, and minimal complications. Therefore, age alone should not be a limiting factor for dental implant therapy.

Functional adaptation of the masticatory system to implant-supported mandibular overdentures

OBJECTIVES

The purpose of this study was to investigate the adaptation behavior of the stomatognathic system after immediate loading (24 to 72 h after surgery) of two implants supporting mandibular overdentures, assessed on insertion and three months later. The study hypothesis was that insertion of the overdentures would significantly change masticatory performance and muscle activity at both times.

MATERIAL AND METHODS

Thirty subjects (nine female, mean age 69.64 ± 11.81 years; 21 male, mean age 68.67 ± 7.41 years) who participated in a randomized clinical trial were included in the study. Each patient was examined three times: (i) at baseline, after already having worn new dentures for three months (T1); (ii) immediately after insertion of the overdentures on the implants (T2); and (iii) after an adaptation period of three months (T3). Examination comprised assessment of masticatory performance with artificial test food (Optocal), and simultaneous bilateral surface EMG recording of the masseter and anterior temporalis muscles. Particle-size distribution (representative value X₅₀ ), maximum muscle contraction (MVC), and total muscle work (TMW; area under the curve) were compared by use of repeated-measures analysis of variance (ANOVA).

RESULTS

At T3, all measured variables (i.e., masticatory performance and muscle activity) were significantly different from those at T1. At T2, no significant changes were observed. The study hypothesis had to be rejected for T2 but accepted for T3.

CONCLUSION

Functional rehabilitation (in terms of masticatory performance and masticatory muscle activity) does not occur immediately after immediate loading of two implants with mandibular overdentures, but requires a significant time for functional improvement.

Implant survival in 1- versus 2-implant mandibular overdentures: a systematic review and meta-analysis

OBJECTIVE

This systematic review was performed to compare the survival of 1- vs. 2-implant overdentures (IODs) in the edentulous mandible.

MATERIALS AND METHODS

Manual and electronic database (PubMed, EMBASE and CENTRAL) searches were performed to identify scientific articles, published in English, reporting on mandibular IODs utilizing unsplinted attachments. Studies were included if they were prospective human studies reporting on two-piece microrough surface implants with a diameter ≥3 mm. Data were extracted by two independent investigators, and an overall inter-investigator kappa score was calculated. A meta-analysis was performed on the included comparative studies.

RESULTS

The search shortlisted 30 prospective studies for data extraction and statistical analysis. The included studies comprised of only two randomized controlled trials (RCTs) comparing 1- vs. 2-IODs, and a further 28 prospective studies. The kappa score calculated was between 0.86 and 1 for the various parameters. One RCT favored 1-IODs (RD: 0.08, 95% CI: 0.01, 0.14) while the other favored 2-IODs (RD:-0.04, 95% CI: -0.27, 0.19). However, the overall random effects model did not reveal a significant risk difference (RD) for implant failure between the two interventions (I(2) = 36.6%, P = 0.209; RD: 0.05, 95% CI: -0.07, 0.18).

CONCLUSIONS

The results of this meta-analysis conclude that the postloading implant survival of 1-IODs is not significantly different from 2-IODs. However, the existing scientific evidence in the literature in terms of prospective comparative studies is scarce. Hence, before recommending the 1-IOD as a treatment modality, long-term observations are needed and a larger range of functional, prosthodontic, and patient-centered outcome measures should be considered.

Objective validity of an implant-retained overdenture with a ball attachment system after marginal mandibulectomy

Implant-retained overdentures are known to improve oral function, but the clinical impact on patients who have had mandibular resections is still debatable. We have treated 16 patients who had such resections for oral cancer and consequent loss of the alveolar ridge, with overdentures supported by osseointegrated implants and ball attachments. To quantify their functional improvement, we evaluated their maximum bite force and masticatory performance. Their function improved significantly, (from 77.5N - 365N, 371% increase in maximum bite force, p<0.001) and masticatory performance increased (from 2.5 - 7.7, 208%, p<0.0001) after the overdentures had been inserted. While individual changes in maximum bite force showed no significant correlation, those in masticatory performance correlated significantly, which suggests that the subjects with poor masticatory function are likely to benefit from retention of an implant. These results indicate that implant-retained overdentures are an effective way to rehabilitate patients after marginal mandibular resection.

Retention of bonded titanium copings fixed to implant abutments

STATEMENT OF PROBLEM

Conical abutments can be laser welded to the abutment base to compensate for differing implant axes. As laser welding requires expensive equipment, alternative methods for bonding the conical abutment part with the abutment base should be considered.

PURPOSE

The purpose of this in vitro study was to evaluate the retention of Ti-6Al-7Nb copings bonded adhesively to Ti-6Al-7Nb abutments and to compare it with the stability achieved by laser welding.

MATERIAL AND METHODS

A total of 104 two-part Ti-6Al-7Nb specimens were prepared and divided into 13 groups with 8 specimens each. In this 2-part study, 3 luting resins (Panavia F 2.0 [PF]; Multilink Automix [MA]; Superbond C&B [SB]) were used with or without metal priming (PR). The laser welding group (LW) served as the control. After storage for 1 or 150 days (150 days with thermal cycling [TC]), push-out retention and welded joint stability were tested. The data were analyzed with ANOVA and the Tukey HSD multiple comparison tests.

RESULTS

The choice of resin, thermal cycling, and metal priming had a significant effect on resin push-out retention. LW provided the strongest retention, followed by PF, MA, and SB. For PF and SB, TC decreased retention. PR did not lead to higher retention but provided better bonding stability when TC was applied.

CONCLUSIONS

The retention values suggest that considering the maximum mastication forces, resin bonding is an appropriate substitute for the laser welding method.

Small-diameter titanium grade IV and titanium-zirconium implants in edentulous mandibles: five-year results from a double-blind, randomized controlled trial

BACKGROUND

The aim of this study was to compare the 5-year survival and success rates of 3.3 mm dental implants either made from titanium-zirconium (TiZr) alloy or from Grade IV titanium (Ti Grade IV) in mandibular implant-based removable overdentures.

METHODS

The core study had a follow-up period of 36 months and was designed as a randomized, controlled, double-blind, split-mouth multicenter clinical trial. Patients with edentulous mandibles received two Straumann Bone Level implants (diameter 3.3 mm, SLActive®), one of TiZr (test) and one of Ti Grade IV (control), in the interforaminal region. This follow-up study recruited patients from the core study and evaluated the plaque and sulcus bleeding indices, radiographic crestal bone level, as well as implant survival and success 60 months after implant placement.

RESULTS

Of the 91 patients who initially received implants, 75 completed the 36 month follow-up and 49 were available for the 60 month examination. Two patients were excluded so that a total of 47 patients with an average age of 72 ± 8 years were analysed. The characteristics and 36-month performance of the present study cohort did not differ from the non-included initial participants (p > 0.05). In the period since the 36-month follow-up examination, no implant was lost. The cumulative implant survival rate was 98.9 % for the TiZr group and 97.8 % for the Ti Grade IV group. Crestal bone level changes at 60 months were not different in the test and control group (TiZr -0.60 ± 0.69 mm and Ti Grade IV -0.61 ± 0.83 mm; p = 0.96). The cumulative implant success rate after 60 months was 95.8 and 92.6 % for TiZr and Ti Grade IV, respectively.

CONCLUSIONS

After 60 months, the positive outcomes of the 36 month results for TiZr and Ti Grade IV implants were confirmed, with no significant differences with regard to crestal bone level change, clinical parameters and survival or success rates. TiZr implants performed equally well compared to conventional Ti Grade IV 3.3 mm diameter-reduced implants for mandibular removable overdentures.

TRIAL REGISTRATION

Registered on www.clinicaltrials.gov: NCT01878331.

Mastication improvement after partial implant-supported prosthesis use

Partially edentulous patients may be rehabilitated by the placement of removable dental prostheses, implant-supported removable dental prostheses, or partial implant fixed dental prostheses. However, it is unclear the impact of each prosthesis type over the masticatory aspects, which represents the objective of this paired clinical trial. Twelve patients sequentially received and used each of these 3 prosthesis types for 2 months, after which maximum bite force was assessed by a strain sensor and food comminution index was determined with the sieving method. Masseter and temporal muscle thicknesses during rest and maximal clenching were also evaluated by ultrasonography. Each maxillary arch received a new complete denture that was used throughout the study. Data were analyzed by analysis of variance for repeated measures, followed by the Tukey test (p < .05). Maximum bite force and food comminution index increased (p < .0001) after implant-supported dental prosthesis and implant fixed dental prosthesis use, with the higher improvement found after the latter's use. Regardless of implant-retained prosthesis type, masseter muscle thickness during maximal clenching also increased (p < .05) after implant insertion. Partial implant-supported prostheses significantly improved masseter muscle thickness and mastication, and the magnitude of this effect was related to prosthesis type.

Do implant overdentures improve dietary intake? A randomized clinical trial

People wearing mandibular two-implant overdentures (IOD) chew food with less difficulty than those wearing conventional complete dentures (CD). However, there is still controversy over whether or not this results in better dietary intake. In this randomized clinical trials (RCT), the amounts of total dietary fiber (TDF), macronutrients, 9 micronutrients, and energy in diets consumed by persons with IOD and CD were compared. Male and female edentate patients ≥ 65 yrs (n = 255) were randomly divided into 2 groups and assigned to receive a maxillary CD and either a mandibular IOD or a CD. One year following prosthesis delivery, 217 participants (CD = 114, IOD = 103) reported the food and quantities they consumed to a registered dietician through a standard 24-hour dietary recall method. The mean and median values of TDF, macro- and micronutrients, and energy consumed by both groups were calculated and compared analytically. No significant between-group differences were found (ps > .05). Despite quality-of-life benefits from IODs, this adequately powered study reveals no evidence of nutritional advantages for independently living medically healthy edentate elders wearing two-implant mandibular overdentures over those wearing conventional complete dentures in their dietary intake at one year following prosthesis delivery.

The impact of edentulism on oral and general health

An adequate dentition is of importance for well-being and life quality. Despite advances in preventive dentistry, edentulism is still a major public health problem worldwide. In this narrative review, we provide a perspective on the pathways that link oral to general health. A better understanding of disease indicators is necessary for establishing a solid strategy through an organized oral health care system to prevent and treat this morbid chronic condition.

Chewing efficiency and electromyographic activity of masseter muscle with three designs of implant-supported mandibular overdentures. A cross-over study

PURPOSE

The aim of this study was to compare the effect of three designs for implant-supported mandibular overdenture on the chewing efficiency and electromyographic (EMG) activity of masseter muscles.

MATERIAL AND METHODS

Eighteen edentulous patients received new maxillary and mandibular dentures (control, CD) before implant placement. After using the dentures for 3 months, patients were randomly divided into six blocks (three patients/block) and received four implants in canine and first molar areas of the mandible. Following osseointegration period, new duplicate mandibular overdentures were successively connected to the implants with: (i) ball attachment on two implants (2BOD), (ii) bar attachment on two implants (2ROD), and (iii) bar attachments on four implants (4ROD) in a random order. Chewing efficiency was measured using chewing gum, and EMG was recorded during clenching (with or without food). Evaluations were made 3 months after using each of the following prostheses: CD, 2BOD, 2ROD, and 4ROD.

RESULTS

All implant-supported overdentures showed a significant increase in chewing efficiency and EMG values when compared to CD. These values increased significantly with 4ROD when compared to 2BOD or 2ROD prostheses. There was no significant difference in chewing efficiency and EMG between 2BOD and 2ROD prostheses.

CONCLUSION

Four-implant-supported overdentures seem to present a functional advantage vs. two-implant-supported overdentures, independent of the chosen attachment system.

Changes in mastication after an immediate loading implantation with complete fixed rehabilitation

OBJECTIVE

This study aimed to measure modifications of mastication after immediate loading full-arch prosthesis (ILFAP) rehabilitation.

MATERIALS AND METHOD

Fourteen patients were observed before and 6 months after ILFAP rehabilitation when masticating two natural, standardized foods (peanut and carrot) and three model foods with increasing hardness. The granulometry of the expectorated boluses from carrot and peanuts was characterized by median particle size (D50), determined at the natural point of swallowing. Chewing time (CT), number of chewing cycles (CC), and chewing frequency (CF) were video recorded. A self-assessment questionnaire for oral health-related quality of life [Geriatric Oral Health Assessment Index (GOHAI)] was also used.

RESULTS

After ILFAP rehabilitation, the mean D50 values for carrot and peanuts were smaller [Repeated Model Procedures (RMP), F = 41, p < 0.001]. Mean CT and CC values recorded with the three model foods decreased, while CF increased regardless of the model food hardness (RMP, F = 14, F = 10, and F = 11, respectively, p < 0.001). The GOHAI score increased from 43 ± 9 to 56 ± 3 (t test, p < 0.001).

CONCLUSION

ILFAP rehabilitation improves the ability to reduce the bolus particle size and the ability to discriminate between different food hardnesses in the 6 months post-surgery period.

CLINICAL RELEVANCE

This study encourages the clinical development of immediate loading implantation with a fixed full-arch prosthesis protocol.

[Significance of dental implants for health care]

Nowadays, endosseous titanium implants must be considered as an evidence-based treatment concept for the replacement of missing teeth. The economic evaluation of scientific evidence suggests that patient satisfaction and oral health-related quality of life may be improved by mandibular implant-retained overdentures over conventional dentures. However, despite promising survival rates reported for dental implants, an increase in the prevalence of peri-implant diseases is emerging. Accordingly, concepts for quality management in education, research, and practice are essential to further improve medical care in implant dentistry.

Immediate loading of mandibular overdentures supported by unsplinted direct laser metal-forming implants: results from a 1-year prospective study

BACKGROUND

At present, only some studies have dealt with immediate loading of unsplinted implants supporting mandibular overdentures. The aim of this prospective study is to evaluate treatment outcomes of mandibular overdentures supported by four one-piece, unsplinted, immediately loaded, direct laser metal-forming (DLMF) implants by assessing implant survival rate, implant success, marginal bone loss, and prosthetic complications.

METHODS

A total of 96 one-piece DLMF implants were inserted in the edentulous mandible of 24 patients. Four implants were placed in each edentulous mandible. Immediately after implant placement, a mandibular overdenture was connected to the implants. At 1-year follow-up, clinical, radiographic, and prosthetic parameters were assessed. Success criteria included absence of pain, suppuration, and implant mobility; absence of continuous peri-implant radiolucency; and distance between the implant shoulder and the first visible bone contact <1.5 mm.

RESULTS

After a 1-year loading time, the overall implant survival rate was 98.9%, with only one implant lost. Among the surviving 95 implants, two did not fulfill the success criteria; therefore, the implant success rate was 97.8%. The mean distance between the implant shoulder and the first visible bone contact was 0.28 ± 0.30 mm (95% confidence interval, 0.24 to 0.32). Some prosthetic complications were reported.

CONCLUSION

Based on the present results and within the limits of this study, the immediate loading of four unsplinted DLMF implants by means of ball attachment-supported mandibular overdentures seems to represent a safe and successful procedure.

A double-blind randomized controlled trial (RCT) of Titanium-13Zirconium versus Titanium Grade IV small-diameter bone level implants in edentulous mandibles--results from a 1-year observation period

BACKGROUND

The use of endosseous dental implants has become common practice for the rehabilitation of edentulous patients, and a two-implant overdenture has been recommended as the standard of care. The use of small-diameter implants may extend treatment options and reduce the necessity for bone augmentation. However, the mechanical strength of titanium is limited, so titanium alloys with greater tensile and fatigue strength may be preferable.

PURPOSE

This randomized, controlled, double-blind, multicenter study investigated in a split-mouth model whether small-diameter implants made from Titanium-13Zirconium alloy (TiZr, Roxolid™) perform at least as well as Titanium Grade IV implants.

METHODS AND MATERIALS

Patients with an edentulous mandible received one TiZr and one Ti Grade IV small-diameter bone level implant (3.3 mm, SLActive®) in the interforaminal region. The site distribution was randomized and double-blinded. Outcome measures included change in radiological peri-implant bone level from surgery to 12 months post-insertion (primary), implant survival, success, soft tissue conditions, and safety (secondary).

RESULTS

Of 91 treated patients, 87 were available for the 12-month follow-up. Peri-implant bone level change (-0.3 ± 0.5 mm vs -0.3 ± 0.6 mm), plaque, and sulcus bleeding indices were not significantly different between TiZr and Ti Grade IV implants. Implant survival rates were 98.9 percent and 97.8 percent, success rates were 96.6 percent and 94.4 percent, respectively. Nineteen minor and no serious adverse events were related to the study devices.

CONCLUSION

This study confirms that TiZr small-diameter bone level implants provide at least the same outcomes after 12 months as Ti Grade IV bone level implants. The improved mechanical properties of TiZr implants may extend implant therapy to more challenging clinical situations.

Patient satisfaction and dissatisfaction with mandibular two-implant overdentures using different attachment systems: 5-year outcomes

BACKGROUND

Different attachment systems for mandibular two-implant overdentures could influence levels of patient satisfaction. Positive consensus of the majority of patients being satisfied does not preclude the possibility of dissatisfaction for some.

PURPOSE

To evaluate patient satisfaction and dissatisfaction before and after 5 years of wearing mandibular two implant overdentures using different attachment systems ; to determine the prognostic relevance of pretreatment complete denture complaints to treatment outcomes.

MATERIALS AND METHODS

A total of 106 edentulous participants enrolled in a clinical trial completed a preliminary self-report inventory of their original complete denture complaints.New complete maxillary dentures and mandibular two-implant overdentures were provided to each participant using one of six different attachment systems. Patient satisfaction was determined at pretreatment; at baseline with mandibular two-implant overdenture insertion; and then annually for 5 years, using visual analogue and Likert-type scales.

RESULTS

Patient satisfaction with mandibular two-implant overdentures showed significant changes pre- to posttreatment(baseline) in all domains, but these were significant immediately and maintained without further significance for 5 years, other than pain with the overdenture. After 5 years, no significant differences were observed with all the attachment systems. Highly significant differences were found with some social and psychological aspects by the fifth year compared to baseline. Diagnostic and prognostic indicators from a pretreatment inventory identified 12 participants (13.5%) who were dissatisfied. These indicators revealed a maladaptive predisposition to mandibular two-implant overdentures.

CONCLUSIONS

The provision of mandibular two-implant overdentures will, in the majority of patients, significantly enhance levels of patient satisfaction for 5 years, as compared to complete mandibular dentures, regardless of the attachment system. Careful evaluation of pretreatment complaints with conventional dentures can possibly identify patient dissatisfaction with mandibular two-implant overdentures [corrected].

Overdenture with immediate load: mastication and nutrition

Lower conventional complete dentures were converted to overdentures retained by two implants with an immediately loaded bar-clip system (n 16). The masticatory performance test was carried out using 'Optocal' after forty chewing strokes. Nutritional condition was evaluated by means of a Mini-Nutritional-Assessment questionnaire. No individual was classified as malnourished. The masticatory performance test demonstrated a statistically significant difference before conversion (baseline) and 3 and 6 months after conversion of the lower conventional complete denture to an implant-retained overdenture (paired-samples t test; P < 0·05). A statistically significant difference before and after 6 months of conversion for nutritional condition (Wilcoxon test; P < 0·05) was also observed. The association between masticatory performance and nutritional assessment demonstrated that a statistically significant difference between masticatory performance of the subgroups classified at baseline as nourished (22·43 %) and those at risk of malnutrition (3·9 %) was only evidenced before conversion (P = 0·006). After the conversion from a lower conventional complete denture to an implant-retained overdenture, at 3 months, the risk of malnutrition and nourished at baseline did not present significant differences in masticatory performance. Nonetheless, the mean masticatory performance potential was 19·86 and 31·98 % for subgroups classified at baseline as at risk of malnutrition and nourished, respectively (P = 0·187). The results before conversion were less favourable for masticatory performance and nutritional condition. The increased retention of the mandibular prosthesis allowed improvement in masticatory performance and nutritional condition.

Mastication in patients treated for malignancies in tongue and/or floor of mouth: A 1-year prospective study

BACKGROUND

People confronted with oral cancer run a high risk of deteriorated masticatory performance. Reduced masticatory function may affect quality of life and food choice. An altered food choice may result in lower intakes for key nutrients and weight loss.

METHODS

Dental state, bite force, and masticatory performance were determined in a group of 45 patients with squamous cell carcinoma of the tongue and/or floor of mouth. Measurements were performed before surgery and at various moments after surgery and/or radiotherapy.

RESULTS

Surgical intervention had a large negative impact on oral function. Radiotherapy further worsened oral function. Also, the recovery of oral function 1 year after surgery was less prominent for the surgery-radiotherapy group than for the surgery group.

CONCLUSION

Objective determination of oral function 1 year after surgery showed that patients treated for malignancies in the tongue and/or floor of mouth had significantly deteriorated masticatory performance, bite force, and dental state.