Five years clinical outcome of maxillary mini dental implant overdenture treatment: A prospective multicenter clinical cohort study.

BACKGROUND: The long-term clinical outcome of mini dental implants (MDIs) to support an overdenture is underreported especially in severely atrophic maxillae and when installed flaplessly. PURPOSE: The current report is a 5-years follow-up of the previously published 2- and 3-years clinical outcome of MDIs supporting a maxillary overdenture in narrow alveolar ridges. MDI survival, marginal bone level, peri-implant health, technical complications, and oral health related quality of life (OHIP) and respective changes over time are reported. MATERIALS AND METHODS: Subjects aged 50 years or older, in need of improvement of maxillary denture retention, were included. The MDIs were 2.4 mm diameter one-piece tapered implants, Class 4 pure Titanium, and lengths 10 or 11.5 mm. Under local anesthesia, 5-6 MDIs were placed in atrophic maxillae with a free-handed flapless approach. One week postoperative the denture was adapted with a retentive soft reliner. The final prosthetic connection was established after 6 months with a metal-reinforced horse-shoe denture. Clinical outcome after 5 years was assessed with probing pocket depts (PPD), bleeding on probing (BoP), and additional cone beam computed tomography (CBCT) MDI bone level measurements were performed. Oral Health-Related Quality of Life (OHRQoL) investigated with OHIP-14 was assessed preoperative, during provisional loading, and after final prosthetic connection up to 5 years. RESULTS: Initially, 31 patients (14 females and 17 males) with mean age 62.30 underwent treatment. In the provisional loading interval, 16 patients encountered 32/185 MDIs failures, resulting in a failure of 17.3%; 170 MDIs were functionally loaded in 29 patients. Additionally, 14 implants were lost in three patients, all of whom had had already previous failures. Reimplantation of 17 MDIs were performed during the provisional loading and 2 MDI after functional loading. After 5 years, the absolute implant failure rate was 46/204 (22.5%), corresponding to a cumulative failure rate of 23.2%. Prosthetic failure was observed in four patients due to implant loss and in two patients related to excessive one-piece implant ball attachment wear, making the 5-years prosthetic success 80.0%. The mean PPD and absence/presence of BoP for 149 implants at 5 years was 4.3 and 0.2 mm, respectively. Average mesial-distal-vestibular-palatal bone loss in the interval 2-5 years was 0.08 mm. No statistically significant difference in marginal MDI bone loss between male or female (p = 0.835), smoking and nonsmoking (p = 0.666) was observed. The five-years total measured CBCT interdental bone level (mesial and distal) correlates with the 5-years PPD (Pearson 0.434; p = 0.01). After 5 years, OHRQoL with the treatment procedure was assessed in 27/31 participants. Decreasing mean total OHIP-14 scores with improved OHRQoL, was observed in 27/31 participants, with values of 21.3 at baseline to 15.6 at the time of provisional loading which significantly (p = 0.006) decrease to 7.3 at the final prosthetic connection. The next 3-5 years further decrease was observed with 6.5 and 4.96, respectively. CONCLUSIONS: Maxillary MDIs for overdentures are an accessible and acceptable treatment option. Although after 5 years between one fifth and one fourth of the MDIs were lost, prosthetic success remains 80.0% and high OHRQoL could be achieved.

Implant-Retained Mandibular Overdentures: Patient-Related Outcome Measurements after Seven Years of Function.

Denture wearers often complain about jeopardized function and reduced quality of life due to lack of prosthesis' retention. Implant-retained mandibular overdentures, on two non-connected implants (2IOD) are well-proven solutions to overcome these issues. We prospectively assessed 69 patients and scrutinized clinical records until at least seven years of function. Thirty-six were retained on Locator® Abutments (LA) and thirty-tree on Ball Abutments (BA). Both systems were compared regarding the type, amount, and total cost of required maintenance. One implant was lost, yielding 98.7% survival after seven years. In total, 438 technical issues occurred: 121 (27.35%) in BA and 317 (72.4%) in LA. Out of these, 343 events (78%) were solved chairside: 191 (43.6%) were replacements of retention caps, 113 (25.8%) were minor acrylic repairs, 26 (5.9%) pressure ulcers had to be relieved, and 13 (3%) were related to abutments. LA required 179 insert replacements compared to 12 in the BA group. The overall initial treatment cost was EUR 3850 (base year of the analysis: 2003). The average total maintenance cost in relation to the initial cost for the LA and BA groups was 19.11 (range 0-82.24%) and 18.91% (range 0-113.26%) respectively (p = 0.540). Conclusions: The seven-year maintenance costs for a 2IOD is acceptable when the patient is regularly checked and professionally maintained. Most events are easily solvable chairside, but a few patients required more expensive interventions, regardless of the type of attachment used.

Comparing Masticatory Performance of Maxillary Mini Dental Implant Overdentures, Complete Removable Dentures and Dentate Subjects.

BACKGROUND: Mini dental implant (MDI) overdenture rehabilitation for the edentulous maxilla is a valuable, less invasive and affordable treatment alternative for complete removable dentures (CRD). However, comparative quantification of masticatory performance in different oral conditions are scarce. PURPOSE: This study compares objective masticatory performance of dentate groups, maxillary CRD and MDI overdentures and subjective masticatory performance in maxillary CRD and MDI overdentures. MATERIALS AND METHODS: Four groups were defined, age 20+ dentate dental students (DS), age 50+ complete dentate subjects (DP), age 50+ maxillary CRD or MDI overdentures/dentate mandible. Objective masticatory performance was evaluated by measuring circular Variance of Hue (VOH) or the mixture degree of two-color chewing gum (Hue-check View Gum® Test). Additionally, subjective masticatory comparison was investigated in the CRD and MDI groups, with a visual analogue scale (VAS) for different food consistencies and the Oral Health Related Quality of Life (OHRQL) OHIP-14 questionnaire. RESULTS: The mean VOH was 0.11 (SD 0.50, range 0.05-0.27) for the dentate dental 20+ students, 0.13 (SD 0.08, range 0.03-0.31) for the 50+ dentate group (p = 0.774), 0.41 (SD 0.41, range 0.14-0.76) for the CRD group and 0.39 (SD 0.18, range 0.07-0.76) for the MDI group (p = 0.725). Based on the VAS scores, no improvement was found between the CRD and the MDI overdenture group (p > 0.050). The mean OHIP-14 total score was 12.10 (SD 15.87, range 0-56) for CRD, while the MDI group (p = 0.039) saw a significant improvement to 2.85 (SD 2.85, range 0-15). CONCLUSION: Comparable results in objective masticatory performance were registered in dentate 20+ and 50+ subjects with a remarkable inferior outcome for the CRD and MDI group. Compared to CRD, MDI overdentures revealed no substantial improvement in subjective and objective masticatory performance. However, for MDI a significant increase in OHRQL was apparent.

Four-implant-supported overdenture treatment in the maxilla. Part I: A randomized controlled split mouth trial assessing the effect of microthreads and abutment connection type on 4 years peri-implant health.

BACKGROUND: According to literature, peri-implant bone loss is minimized on implants with microthreaded neck design and internal type of abutment connection. However, most clinical studies may be biased due to confounding factors. PURPOSE: This nonblinded RCT assessed the effect of implant neck (microthreaded vs non-microthreaded) as well as the type of abutment connection (internal conical vs external flat-to-flat) on peri-implant bone stability and peri-implant health after at least 36 months. MATERIALS AND METHODS: Twenty-five patients were treated with a maxillary implant-supported bar-retained overdenture on four different implant types: internal connection with microthreads (I-MT), internal connection without microthreads (I-NMT), external connection with microthreads (E-MT), and external connection without microthreads (E-NMT). To control confounding factors, all other design features were similar. A linear mixed-model analysis or mixed-model logistic regression analysis was used to determine the effect of implant type on bone level, probing pocket depth, bleeding on probing, and plaque. RESULTS: Four out of 98 implants (4.1%) placed in 25 patients failed during provisionalization and were replaced. Mean overall bone loss after 6 months was 0.39 mm (SD 0.62, range 0.00-3.48) with limited additional bone loss of 0.04 mm (SD 0.54, range -1.80-1.63) after at least 3 years. Microthreads or connection type had no effect on the bone level, probing pocket depth, bleeding on probing, nor plaque. CONCLUSIONS: With 96% of implant survival, the maxillary overdenture supported with a bar on four implants yield a predictable outcome and the implant-abutment connection type (internal vs external) and implant neck design (microthreaded vs non-microthreaded) have no influence on peri-implant bone remodeling after initial bone remodeling nor up to 4 years of function. Peri-implant bone levels are within international success standards and peri-implant health is indicative of absence of peri-implantitis.

Four-implant-supported overdenture treatment in the maxilla. Part II: Speech- and oral health-related quality of life in patients with implant-supported overdentures in the maxilla-A prospective 3-year follow-up.

BACKGROUND: Implant-supported overdentures (IOD) are becoming a more commonly used treatment in the dental practice and it risks causing speech problems. PURPOSE: The aim of this study was investigating the changes in speech, satisfaction with speech, and overall oral health-related quality of life (OHRQoL) in edentulous patients during and after treatment with maxillary IODs. MATERIALS AND METHODS: Twenty-one patients receiving an IOD participated in speech assessment. They were examined preoperatively with their conventional denture (CD) with full palatal coverage, after connection of the implant-bar connected denture, without palatal coverage, and 3 years thereafter. The examination included assessment of articulation in speech, OHRQoL based on total OHIP-14, and satisfaction with overall oral health and speech (visual analogue scale). RESULTS: There was a reduction in mean number of articulation disorders from 1.00 at baseline to 0.55 at connection, although statistically insignificant (p = 0.059). Especially the /s/ sound is vulnerable. At 3 years follow-up, still 6/16 (37.5%) of the patients suffered from this speech problem. Overall satisfaction improved from 64.05/100 at baseline to 82.95/100 at connection (p = 0.008) and remained unchanged with 81.69/100 after 3 years follow-up. Patients' satisfaction with speech increased from 70.62/100 with CD to 82.63/100, 3 years follow-up (p = 0.009). Total OHIP-14 decreased from 21.45/56 with CD to 8.00/56 (p < 0.001) with IOD and 6.13/56 3 years after connection (p = 0.001). Significant improvement of all seven domains in OHRQoL was observed with IOD compared to CD. CONCLUSIONS: Patients treated with maxillary IODs show improved OHRQoL 3 years after connection of the IOD compared to the CD. Even though patients reported improvement of satisfaction and OHRQoL, articulation disorders were still present, suggesting that patients should be informed about possible speech issues.

Articulation, oral function, and quality of life in patients treated with implant overdentures in the mandible: A prospective study.

BACKGROUND: Modifications of facial and oral structures affect aesthetic appearance, orofacial functions, and have impact on quality of life. PURPOSE: This study determined alterations of articulation, oromyofunctional behavior, and Oral Health Related Quality of Life (OHRQoL) in patients replacing complete removable dentures by implant retained overdentures in the mandible. MATERIALS AND METHODS: Twenty-one fully edentulous patients received mandibular overdenture retained on a bar connecting two titanium dental implants. Patients were evaluated after receiving a new set of fully removable dentures (stage 1), after surgery during provisionalization on healing abutments (stage 2), and after final connection to the bar (stage 3). Assessments were taken by speech therapists and included evaluation of: articulation (picture naming and reading); oromyofunctional behavior; OHRQoL (OHIP-14 questionnaire), and overall satisfaction and speech (VAS). To measure changes over time, Wilcoxon matched-pairs signed-rank-test and McNemar test was used. RESULTS: There was no significant impact of the treatment on speech nor on the results of oromyofunction. In stage 1, patients had different kinds of articulation errors (mean:1.21) which evolved to 0.71 and 0.67. In stage 3, especially problems with the /s/ sound are seen in 37% (7/19) of the participants. Results of OHRQoL and satisfaction reveal that the average of satisfaction with oral health evolved from 67% to 63% and finally 78%. OHIP-14 total score was 17.4/56 in stage 1, remained unchanged in stage 2 and evolved in stage 3 to 9.8/56 (P: .010). This indicates improvement. Satisfaction with speech evolved significantly from 68% pretreatment to 82% in stage 3 (P: .013). CONCLUSION: Despite existing articulation and oromyofunctional disorders after treatment, people are very satisfied with their OHRQoL and their speech. Impact of mandibular denture wearing on OHRQoL declines once connected. It's important to inform patients that speech and oromyofunctional disorders may occur during treatment where especially the /s/ sound is vulnerable.

"Longitudinal Oral Health-Related Quality of Life in maxillary mini dental implant overdentures after 3 years in function".

OBJECTIVES: Longitudinal evaluation of Oral Health-Related Quality of Life (OHRQoL) during treatment of flaplessly placed, one-piece mini-dental-implants (MDIs) for maxillary overdentures is rarely investigated, nor is the impact of MDI failures. MATERIAL AND METHODS: This multicenter prospective cohort study evaluated the 3-year outcome of 5-6 MDIs in the edentulous maxilla in patients above 50 years with dentate mandible. Provisional dentures were provided before final prosthetic connection was established at 6 months. Postoperative discomfort was assessed using a visual analogue score (VAS). OHRQoL was investigated using the Oral Health Impact Profile (OHIP)-14 at baseline (preoperatively), postoperatively, post-prosthetic connection and after 3 years in function. RESULTS: 164 (78.4%) of the 204 placed MDIs were still in situ after 3 years, in 29/31 patients. Two patients lost 5/6 MDIs resulting in two prosthetic failures (6.45%). With regard to pain, a score of 4.1/10 (SD 2.8) was recorded on day 1, and 1.1/10 (SD 1.7) on day 7. A decrease in total OHIP-14 scores was observed postoperatively (15.6; SD 12.8) as compared to baseline (21.3; SD 13.1), with improvement of OHRQoL. Furthermore, this was statistically significant at connection of the final prosthesis (7.3; SD 6.7) (p = .006). The OHIP-14 improved less (p = .011) when experiencing one or more implant losses (9.5; SD: 9.85), in comparison with no implant loss (20.7; SD: 13.97). A failure of one MDI did not affect OHIP-14 score (p = .658); however, multiple failures did (p = .007). CONCLUSION: Maxillary MDI overdenture treatment yields significant OHRQoL improvement when at least 5 MDIs survive, preserving functional comfort.

The Long-Term Effect of Adapting the Vertical Position of Implants on Peri-Implant Health: A 5-Year Intra-Subject Comparison in the Edentulous Mandible Including Oral Health-Related Quality of Life.

Despite high success rates of dental implants, surface exposure may occur as a consequence of biologic width establishment associated with surgery. This prospective split-mouth study evaluated the effect of early implant surface exposure caused by initial bone remodeling on long-term peri-implant bone stability and peri-implant health. Additionally, Oral Health-Related Quality of Life (OHRQoL) was assessed by means of the Oral Health Impact Profile-14 (OHIP-14). Twenty-six patients received two non-splinted implants supporting an overdenture in the mandible by means of locators. One implant was installed equicrestally (control) and the second one was installed subcrestally, taking at least 3 mm soft tissue thickness into account (test). During initial bone remodeling (up to 6 months postoperatively), equicrestal placement yielded 0.68 mm additional surface exposure compared to subcrestal placement (p < 0.001). Afterwards, bone level and peri-implant health were comparable in both treatment conditions and stable up to 5 years. The implant overdenture improved OHRQoL (p < 0.01) and remained unchanged thereafter (p = 0.51). In conclusion, adapting the vertical position of the implant concerning the soft tissue thickness prevents early implant surface exposure caused by initial bone remodeling, but in a well-maintained population, this has no impact on long-term prognosis. The treatment of edentulousness with an implant mandibular overdenture improves OHRQoL.

Cost-effectiveness analysis of two attachment systems for mandibular overdenture.

OBJECTIVES: This study analysed the cost-effectiveness of two different attachments for the 2-implant overdenture (2IOD) in edentulous mandibles. MATERIALS AND METHODS: When considering alternative treatments, cost-effectiveness analysis is an important factor for stakeholders (patient, clinician, social security, insurance company, etc.). A general practice population (n = 116) was treated between 2003 and 2013 with a mandibular 2IOD with 2 different ball/stud attachment systems, one spherical (Group D) and one cylindrical (Group L). Patient well-being was assessed with OHIP-14-Total (OHIP-14-T), at intake and annually up to 5 years, to calculate the health effect. Initial and maintenance costs of both treatments were inventoried. The cost-effectiveness was compared. Annual discount rates of 4% and 1.5% were applied to future costs and health outcomes, following Dutch guidelines. Prices were adjusted to the year 2003. To offset the uncertainty in relevant input parameters, a sensitivity analysis was performed using bootstrap analysis. Significance was set at p < .05. RESULTS: The health effect was 6.36 (SD 5.32) for Group D and 8.54 (SD 5.63) for Group L. The sum of the discounted costs up to 5 years was EUR 4,210.98 (SD 634.75) for the D and EUR 3,840.62 (SD 302.63) for the Group L (p = .005). The bootstrapping reports that L abutment clearly dominates the D abutment in terms of cost-effectiveness. CONCLUSIONS: The 2IOD on the L abutment is dominant compared to the 2IOD on D abutment, in a 5-year perspective.

Five years follow-up of mandibular 2-implant overdentures on locator or ball abutments: Implant results, patient-related outcome, and prosthetic aftercare.

BACKGROUND: It is uncertain, which is the optimal attachment for a mandibular 2-implant overdenture (2IOD). PURPOSE: To assess 5 years clinical implant outcome, prosthetic maintenance, cost, and PROMs of two cohorts receiving 2IOD on ball or stud abutments in a comparative study. MATERIALS AND METHODS: Ninety edentulous individuals were treated with balls (n = 34) or locator (n = 56). Implant survival, bone-to-implant level, prosthetic outcome, technical maintenance, and OHIP-14 were assessed. Statistics to compare between baseline and 1/5 years and between groups were t-test or Mann-Whitney (P < .05); chi-square was adopted to analyze plaque and technical maintenance or interventions between groups. RESULTS: Five years implant survival was 98.7%, irrespective of attachment. Overall mean bone loss was 1.1 mm, probing pocket depth 1.92 mm, bleeding score 0.60, plaque score 1. Plaque accumulated more on locators (P = .023). OHIP-14 declined from 18.1 to 2.7 irrespective of attachment. Retention for balls was better (P < .005), locators required more maintenance (P < .001), caused by retention-adjustment (P < .001) or ulcers/pain (P = .014). Five years maintenance-cost was 11% of initial cost, irrespective of attachment. CONCLUSIONS: Balls and locators yield stable 5-years implant outcome and improved Oral Health Related Quality of Life (OHRQoL). Locators required more maintenance and resulted in a lower retention. Maintenance costs are minimal but may affect OHRQoL at least for stud abutments.

Five-year study of mandibular overdentures on stud abutments: Clinical outcome, patient satisfaction and prosthetic maintenance-Influence of bone resorption and implant position.

OBJECTIVES: This prospective study analyses the 5-year clinical outcome, patient satisfaction and the technical outcome of a 2-implant overdenture on stud abutments. In addition, the influence of mandibular resorption and implant position on these outcomes was assessed. MATERIAL AND METHODS: Patients received two implants in a one-stage delayed protocol. Final prosthesis on stud abutments was finalized after 3 months. Implant survival, bone loss, plaque and sulcus bleeding index, OHIP-14, technical outcome and costs were assessed after 5 years. The Cawood-Howell classification defined the mandibular resorption. Inter-implant distances and angles (frontal, sagittal) were digitally measured. The significance level was p < .05. RESULTS: Fifty-six patients, 23 female and 33 males (mean age = 66.3, range 41-82), completed the follow-up. No implants were lost. Radiographical crestal bone loss was on average 1.25 mm (standard deviation SD 1.06), bleeding index was 0.75 (SD 0.73), and plaque index was 1.15 (SD 0.75) and higher for low mandibles (p = .001). The OHIP-14 reduction post-connection and after 5 years was significant (p < .001). Five-year maintenance required on average 6.7 (SD 4.8, range 0-25) interventions per patient. A larger inter-implant distance was associated with fewer replacement of retention inserts (p = .034) and less interventions (p = .006). Larger frontal (p = .023) and sagittal (p = .046) inter-implant angles (non-parallelism) required more inserts. The maintenance cost negatively influences the patient satisfaction (p = .004). 83% of the stud abutments showed wear. CONCLUSION: The implant overdenture on cylindrical stud abutments is a good and stable solution, irrespective of the resorption profile of the mandible. OHIP-14 improved permanently up to 5 years but is negatively influenced by complication cost. A small inter-implant distance, more frontal, sagittal inter-implant divergence increased maintenance.

Speech evaluation during maxillary mini-dental implant overdenture treatment: A prospective study.

Large proportions of patients are edentulous and wear removable dentures leading to reduced functional comfort and less oral health-related quality of life. Satisfaction with the oral situation after implantation depends on the outcome in eating comfort, speech comfort and aesthetics. Modification in form and location of the teeth may affect speech. The aim of this study is to determine speech, oromyofunctional behaviour, satisfaction with the treatment and the impact on quality of life of the horse-shoe overdenture retained by mini-dental implants (MDIs) in the maxilla. This prospective multicentre cohort study included 32 patients for treatment. 5 to 6 implants were placed, traumatically piercing the mucosa. Patients were evaluated three times during treatment (pre-operatively with conventional prosthesis including full palatal coverage (CD), post-operatively with provisionally relined CD and with horse-shoe overdenture on MDI). The assessment included a phonetic evaluation, examination of oromyofunctional behaviour, evaluation of the impact on quality of life (OHIP-14) and a rating of satisfaction with the treatment and speech on a visual analogue scale. Several speech sounds are found to be disturbed before treatment. In the next two stages of the treatment, the number of speech issues decreases. In the final stage, ten people show minor speech problems, especially with the /s/ sound. In this stage, seven people still present with oromyofunctional problems, especially whistling problems. In this last stage, people are very satisfied with the treatment (83%) and with speech (84%). The impact on quality of life is low (8.23/56).

Improvement of Quality of Life with Implant-Supported Mandibular Overdentures and the Effect of Implant Type and Surgical Procedure on Bone and Soft Tissue Stability: A Three-Year Prospective Split-Mouth Trial.

In fully edentulous patients, the support of a lower dental prosthesis by two implants could improve the chewing ability, retention, and stability of the prosthesis. Despite high success rates of dental implants, complications, such as peri-implantitis, do occur. The latter is a consequence of crestal bone loss and might be related to the implant surface and peri-implant soft tissue thickness. The aim of this paper is to describe the effect of implant surface roughness and soft tissue thickness on crestal bone remodeling, peri-implant health, and patient-centered outcomes. The mandibular overdenture supported by two implants is used as a split-mouth model to scrutinize these aims. The first study compared implants placed equicrestal to implants placed biologically (i.e., dependent on site-specific soft tissue thickness). The second clinical trial compared implants with a minimally to a moderately rough implant neck. Both studies reported an improvement in oral health-related quality of life and a stable peri-implant health after three years follow-up. Only equicrestal implant placement yielded significantly higher implant surface exposure, due to the establishment of the biologic width. Within the limitations of this study, it can be concluded that an implant supported mandibular overdenture significantly improves the quality of life, with limited biologic complications and high survival rates of the implants.

A randomized controlled clinical trial assessing initial crestal bone remodeling of implants with a different surface roughness.

PURPOSE: The aim of current split-mouth study is to compare crestal bone loss of hybrid with moderately rough implants in patients with a bar-supported mandibular overdenture. MATERIALS AND METHODS: Fully edentulous patients were enrolled for treatment with implant-supported overdentures. Each patient received two implants of which one moderately rough (Sa: 1.3 µm) and one hybrid surface implant (moderately rough implant body [Sa: 1.3 µm] and a minimally rough implant neck [Sa: 0.9 µm]). Beside the difference in implant surface the two implants are identical. After 3 and 12 months, peri-apical radiographs were taken to assess crestal bone levels and a Wilcoxon signed-rank test was used for pairwise comparison. RESULTS: Forty-two implants were placed in 21 patients and no failures occurred after 1 year. An overall mean crestal bone loss of 0.40 mm (SD: 0.76; range: 0-3.93) and 0.35 mm (SD: 0.59; range: 0-2.56) was registered after a mean follow-up of 3.4 and 15.8 months. There was no statistical significant difference in crestal bone loss between the different implant surfaces or between the different time intervals. CONCLUSION: From this randomized controlled trial, it can be concluded that hybrid surface implants may be a viable alternative for implant treatment in the edentulous mandible.

Impact of crestal bone resorption on quality of life and professional maintenance with conventional dentures or Locator-retained mandibular implant overdentures.

STATEMENT OF PROBLEM: The influence of the mandibular resorption profile on clinical outcome after converting a conventional complete denture into a Locator-retained implant overdenture is unknown. PURPOSE: The purpose of this prospective study was to assess the oral health-related quality of life (OHRQoL) and prosthetic maintenance of mandibular overdentures on 2 Locator abutments in relation to the resorption degree of the edentulous mandible. MATERIAL AND METHODS: Twenty-five participants were treated and classified according to the Cawood and Howell (CAW-H) resorption classification for the resorption profile of the mandible, CAW-H group III-IV (n=14) and CAW-H group V (n=11). Participants received conventional complete dentures (CDs) before implant placement and immediate nonfunctional loading on Locators with a resilient liner. After 3 months, the attachments were functionally activated. Assessments were made using the Oral Health Impact Profile 14 (OHIP-14) questionnaires with existing CDs and new CDs at 1, 3, and 15 months after loading. Prosthetic maintenance (repairs, rebasings, replacement of retention parts) and biological prosthetic aftercare were assessed. For comparison between groups, the Kruskal-Wallis and Mann-Whitney U tests were applied for continuous and ordinal variables and the chi-square test for cross-tabulations. To analyze repeated OHIP-14 scores, the Friedman test was used for ordered alternatives to test whether the measurements differed (overall significance level α=.05). Then the Wilcoxon signed rank test was conducted to detect specific differences (α=.05). RESULTS: OHIP-14 scores decreased significantly after implant placement and functional connection for the whole population (P<.001) and for both sub groups, the CAW-H group III-IV (P<.001) and the CAW-H group V (P=.013). CAW-H group V participants needed more retention inserts than CAW-H group III-IV participants (26 versus 3, respectively; P=.006). The incidence of repair and rebasing was limited for both groups, and biological aftercare and pain relief were comparable. CONCLUSIONS: Changing a CD to an overdenture significantly improved ORLQoL regardless of the resorption degree, but heavily resorbed mandibles require more replacements of retention inserts.

Adapting the vertical position of implants with a conical connection in relation to soft tissue thickness prevents early implant surface exposure: A 2-year prospective intra-subject comparison.

AIM: To evaluate the effect of soft tissue thickness on bone remodelling and to investigate whether implant surface exposure can be avoided by adapting the vertical implant position in relation to the soft tissue thickness. MATERIALS AND METHODS: Twenty-five patients received two non-splinted implants supporting an overdenture in the mandible. Soft tissue thickness was measured using bone sounding and ultrasonically. One implant was installed equicrestally (control), and the vertical position of the second implant was adapted to the site-specific soft tissue thickness (test). Crestal bone levels were determined on digital peri-apical radiographs and compared with baseline (implant placement). RESULTS: Twenty-five patients were consecutively treated. No implants failed during the follow-up. A significant correlation was observed between soft tissue thickness and bone level alterations after 6 months (ultrasound ICC = 0.610; bone sounding ICC = 0.641) with inferior bone levels for equicrestal implants when thin tissues are present. Subcrestal implants showed significantly better bone levels after 6-month (n = 24, 0.04 mm versus 0.72 mm; p < .001), 1-year (n = 24, 0.03 mm versus 0.77 mm; p < .001) and 2-year follow-up (n = 24, 0.04 mm versus 0.73 mm; p < .001). CONCLUSION: Initial bone remodelling was affected by soft tissue thickness. Anticipating biologic width re-establishment by adapting the vertical position of the implant seemed highly successful to avoid implant surface exposure.

Peri-implant health, clinical outcome and patient-centred outcomes of implant-supported overdentures in the mandible and the maxilla.

OBJECTIVES/AIMS: The primary aim of this retrospective pilot study was to evaluate the clinical outcome of overdentures on four non-splinted maxillary implants compared to the mandible using locator attachments and secondly to assess patient's opinion of the treatment. MATERIALS AND METHODS: The treatment protocol used here is summarised as a single-stage surgical approach followed by immediate loading (same day in 12 of 17 patients) of a removable prosthesis in the maxilla and mandible. Most of the implants were installed into fresh extraction sockets. Clinical outcomes were evaluated in 68 southern implants, straight (non co-axis) or angulated (co-axis) in 17 patients. Patients were examined by independent examiners at an average follow-up of 14.5 months after implant placement. RESULTS: Outcomes measured were implant survival, bone loss, bleeding on probing, probing pocket depths and plaque score in addition to quality of life measured with OHIP-14 questionnaires. An overall implant survival of 100% was achieved. The mean marginal bone level (mm) over the entire cohort of 66 measured implants was (1.4 mm; range, 0-5.5). A significant difference (P=0.01) was found between bone level, from implant head to bone contact in the maxilla (M, 0.9 mm; s.d., 1.1; range, 0-4) and the mandible (M, 1.7; s.d., 1.0; range, 0-5.5). The marginal bone-to-implant head distance with the angulated co-axis implants was 1.9 mm (s.d., 1.5; range, 0-5.5) compared to non co-axis, mean 1.2 mm (s.d., 1.1; range, 0-4) (P=0.01). The OHIP-14 overall mean was 3.3 (out of a maximum of 56). CONCLUSION: The implant survival was 100% and the patients benefited from the overdenture treatment on four non-connected implants. The extremely low OHIP-14 indicated a very high level of patient satisfaction following treatment. The results of this study merit further long-term investigation to fully investigate the success of immediately loading implants in the maxilla as well as cost-benefit.

The current use of patient-centered/reported outcomes in implant dentistry: a systematic review.

AIM: To provide an update on the use of Patient-Reported Outcome Measures (PROMs) in the field of implant dentistry (1); to compare PROMs for prostheses supported by one or more implants to alternative treatment options or a healthy dentition (2). MATERIALS AND METHODS: The dental literature was searched on PubMed until December 31, 2014, using a general search algorithm. An overall quantitative analysis was performed, and a qualitative appraisal was made on the output of the last 6 years. Per type of edentulism and prosthetic treatment, the general search algorithm was refined in order to select controlled studies comparing PROMs for prostheses supported by one or more implants to alternative treatment options or a healthy dentition. RESULTS: With nearly half of the output (300 of 635) published in the last 6 years, there is a growing interest in PROMs by the scientific community. When scrutinizing the 300 most recent publications, only 84 controlled studies could be identified among which 38 RCTs and 31 cohort studies. An "ad hoc" approach is commonly employed using non-standardized questions and different scoring methods, which may compromise validity and reliability. Overall, 39 eligible papers related to fully edentulous patients treated with an implant overdenture (IOD) and 9 to fully edentulous patients treated with a fixed implant prosthesis (FIP). There is plenty of evidence from well-controlled studies showing that fully edentulous patients in the mandible experience higher satisfaction with an IOD when compared to a conventional denture (CD). This may not hold true for fully edentulous patients in the maxilla. In general, fully edentulous patients seem to opt for a fixed or removable rehabilitation on implants for specific reasons. Data pertaining to partially edentulous patients were limited (FIP: n = 6; single implants: n = 16). In these patients, the timing of implant placement does not seem to affect patient satisfaction. Patients seem to prefer straightforward implant surgery over complex surgery that includes bone grafting. CONCLUSION: There is an urgent need for standardized reporting of PROMs in the field of implant dentistry. Fully edentulous patients in the mandible experience higher satisfaction with an IOD when compared to a CD. All other types of prostheses have been underexposed to research.