Prosthetic Aftercare Research Articles

Long-Term Prosthetic Aftercare of Mandibular Implant-Supported Overdenture

Background: Two of the most popular resilient attachment systems for mandibular implant-supported overdenture (MISOD) are locator and ball attachments. The purpose of the present retrospective cohort study was to assess the long-term prosthetic aftercare and oral hygiene status in edentulous patients rehabilitated with MISOD. Materials and Methods: Forty-five consecutive patients were included (22, group A- ball vs. 23, group B- locator attachments). Attachment incorporation into the MISOD was conducted in a direct (chair-side) intraoral technique at the time of denture insertion. Routine follow-up included yearly visits. The number of visits requiring prosthetic aftercare, either during the follow-up or during the additional visit, was recorded. Outcome parameters included—prosthetic aftercare—the number of aftercare (primary outcome parameter) visits, and dental treatment received (pressure sores relief, liner changes due to loss of retention, loss of retention due to debris accumulation, denture repair—secondary outcome parameters); oral hygiene—gingival index (primary outcome parameter). Results: The mean follow-up of the entire study population was 84 ± 21 months, range 39–120 months. Statistical analysis revealed a lower need for prosthetic aftercare interventions in group A (p < 0.001). The mean number of visits dedicated to pressure sores relief (6.09 ± 1.04 vs. 3.03 ± 0.77, p < 0.001) and liner exchange due to loss of retention (5.6 ± 1.03 vs. 2.09 ± 1.04, p < 0.001), were significantly lower in group A. Debris (food/calculus) accumulation inside the attachment was noted only for the locator’s group (p < 0.001). No statistically significant differences between the groups were noted for denture repair (p = 0.318). Oral hygiene also exhibited statistically significant differences in favor of group A (2.3 ± 0.3 vs. 1.03 ± 0.2, p < 0.001). Conclusions: It can be concluded that using ball attachments for MISOD yields less need for aftercare treatments and improved oral hygiene status over the years.

Immediate versus Delayed Attachment Incorporation Impact on Prosthetic Aftercare among Mandibular Implant-Supported Overdenture Wearers.

Background: Substantial effort is dedicated to finding the most favorable parameters that will ensure low aftercare demands among edentulous patients wearing mandibular implant supported overdentures (MISODs). The purpose of this retrospective cohort study was to compare prosthetic aftercare between MISOD patients with a simultaneous (group A) vs. a three-week settling in period (group B) prior to attachment incorporation. Methods: Forty-five patients enrolled in this study. Two implants per patient were placed using a two-stage implant insertion protocol. Second-stage surgery was performed after three months. All patients received ball attachments using the direct (chairside) incorporation method. Twenty-two patients received their dentures with simultaneous attachment activation and the rest—twenty-three patients—after a three-week settling in period. Patients’ files were scanned for aftercare visits. Outcome parameters included sore spot relief, attachment incorporation, and denture repair. Additionally, gingival index measurements were compared. Confounding factors included age, gender, and implant dimensions. Results: The mean follow-up for the entire cohort was 84 ± 21 months, and the range 39–120 months. The mean number of visits for group A vs. B respectively: pressure sores relieve (3.63 ± 0.84 vs. 3.71 ± 0.61, p = 0.581), liner exchange due to loss of retention (2.09 ± 1.03 vs. 2.31 ± 1.04 p = 0.487), and gingival index (1.3 ± 0.3 vs. 1.03 ± 0.2, p = 0.653) exhibited no statistically significant differences between the tested groups. No statistically significant differences between the groups were also noted for the denture repair aftercare treatments (p = 0.318) and the independent variables including age, gender, and implant length. Conclusions: Prosthetic aftercare in MISOD wearers is similar whether a simultaneous or a three-week settling in period for attachment incorporation is applied.

Prosthetic aftercare, mastication, and quality of life in mandibular overdenture wearers with narrow implants: A 3-year cohort study

ObjectivesThis cohort study investigated clinical, functional, and quality of life outcomes, along with prosthetic maintenance events in mandibular overdenture (MO) wearers for 3 years. MethodsThirty MO wearers with narrow diameter implants (NDIs) and locking taper stud abutments (Facility-Equator system) were annually monitored by registering the visible plaque index (VPI), peri‑implant inflammation (PI), calculus presence (CP), probing depth (PD), bleeding on probing (BOP), secondary implant stability (ISQ), marginal bone loss (MBL), masticatory performance and dental impact in daily life (DIDL) questionnaire domains. Multilevel mixed-effects linear regression was performed to analyse changes over time. Chi-square tests were performed to analyse the relationship between the appearance of prosthetic complications and maintenance occurrences. The survival rate of patients with NDIs was calculated using the Kaplan–Meier test. ResultsTwenty-six individuals attended all follow-ups, the survival rate of 83.3% in the first year was maintained, and no one implant was lost over the 3-year period. There were significant differences for PD between 1 and 3 years (p ≤ 0.01) and between 2 and 3 years for PI (p ≤ 0.01), GI (p ≤ 0.01), ISQ (p = 0.02), and MBL (p ≤ 0.01). All masticatory performance outcomes showed significant differences (p ≤.01). Prosthetic maintenance events decreased significantly over time. Appearance, general performance, and eating and chewing domains presented high effect sizes. ConclusionContinued changes were observed in the clinical parameters of MO users over the 3-year period. In addition, most functional parameters, except for particle homogenization, improved significantly over time. The positive impact on quality of life is likely related to the significant reduction in prosthetic maintenance events. Clinical significancePeriodic returns to assess peri‑implant tissues and MO maintenance should be performed to ensure the success of rehabilitation to assure improvements in masticatory function and oral health-related quality of life.

Long-Term Prosthetic Aftercare of Two- vs. Four-Ball Attachment Implant-Supported Mandibular Overdentures

Little is reported about the prosthetic aftercare of implant-supported mandibular overdentures regarding the number of implants placed. The purpose of this study was to evaluate the prosthetic aftercare among edentulous patients restored with two vs. four mandibular implant-retained overdentures (MISOD). Forty-six consecutive edentulous patients treated by a new MISOD were retrospectively studied. Twenty-five patients had two-ball attachment MISOD (Group A), and 21 had four-ball attachment MISOD (Group B). The total amount of aftercare visits was recorded, as well as the type of treatments required (pressure sore spots relief, attachment liner replacement due to loss of retention, and metal ball attachment replacement due to wear). The mean follow-up duration was 93 ± 57 months (range 9–246 months). None of the implants was lost. There were significantly more visits for pressure sore spots relief in Group A vs. Group B (6.2 ± 2 in group A and 4.09 ± 1.54 in group B, p < 0.0001). Differences in the other two tested parameters (number of visits for liner replacement (2.3 ± 1.84 in group A and 2.4 ± 1.63 in group B) and attachment replacement (2.36 ± 1.85 in group A vs. 2.48 ± 1.63 in group B) yielded a non-significant outcome (p = 0.814 for liner replacement and p = 1.000 for attachment replacement). The use of four-ball attachments in MISOD was more beneficial than two-ball attachments with regards to the aftercare of pressure sore spots. The number of implants did not influence the mechanical wear.

Implant-supported mandibular overdentures: a retrospective case series study in a daily dental practice

BackgroundEvaluation of dental implant treatment is mostly based on studies with well-controlled study groups treated within a university-based setting. There are no long-term observational practice-based studies known on implant-supported overdentures. The present retrospective study deals with implant survival, peri-implant hard and soft tissue health, surgical and prosthetic aftercare, and satisfaction of patients treated with an implant-supported mandibular overdenture in a daily dental practice.Materials and methodsWithin the years 2006 till 2015, 295 patients were treated with two, three, or four implants for mandibular overdenture treatment in a daily dental practice in Zaandam, The Netherlands. Outcome parameters were scored at a routine yearly inspection including implant loss, plaque index, gingival index, bleeding index, presence of calculus, probing depth, and satisfaction with implant-supported overdenture. Radiographic analysis was performed to assess peri-implant bone changes. Surgical and prosthetic aftercare was obtained from the medical record.ResultsA total of 133 patients were seen for an evaluation visit (mean follow-up 51.2 months). Cumulative implant survival rate in the 2-implant group, 3-implant group, and 4-implant group was 100%, 99.1%, and 97.8% respectively, with a mean peri-implant bone loss of 0.53 mm, 0.61 mm, and 0.40 mm. Patients’ satisfaction was high in all groups.ConclusionIt was demonstrated, within the limitations of this study, that patients, who were treated with an implant-supported mandibular overdenture in a daily dental practice, experienced a high cumulative implant survival rate and a good peri-implant health, and were very satisfied.Trial registrationNetherlands Trial Register, NL8867. Registered 15 September 2020—retrospectively registered.

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

It is uncertain, which is the optimal attachment for a mandibular 2-implant overdenture (2IOD). 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. 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. 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. 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.

Mandibular Overdentures Supported by Two vs Four Endosteal Implants: A Retrospective Cohort Study

Documentation of marginal bone resorption caused by implant-supported mandibular overdentures is scarce. This study sought to evaluate marginal bone resorption, survival rate, patient satisfaction, peri-implant soft tissue status, and prosthetic aftercare of mandibular overdentures supported by two vs four implants. This retrospective cohort study evaluated 92 edentulous patients presented to the Implant Center of Tehran University of Medical Sciences; out of which, 46 patients received overdentures supported by two Implantium implants (group A), while the remaining 46 received overdentures supported by four Implantium implants (group B). Standard radiographic indices were assessed following the delivery of overdenture and after 2 years of functional loading. Clinical evaluation was performed after 2 years of function. Data were analyzed using the t test (for continuous variables) and the Mann-Whitney test (for ordinal variables). In group A, two implants were lost in one patient. The groups were not significantly different in terms of clinical or radiographic parameters (p > 0.05). Patient satisfaction and prosthetic aftercare were not significantly different in groups A and B (p > 0.05). During the 2-year evaluation period, the clinical and radiographic parameters were the same in patients who received overdentures supported by two or four implants. Successful results may be obtained by the use of mandibular overdentures supported by two or four implants.

Prefabricated taper crowns for the retention of implant superstructures: Three-year results of a prospective clinical trial

Statement of problemNonrigid retainer systems for removable implant superstructures are associated with negative effects such as rocking and increased load on the denture base. Rigid retainer systems such as telescopic crowns reduce these negative effects, but their fabrication demands highly skilled dental technicians and is therefore expensive. Whether a protocol with prefabricated retainers will reduce production time is unclear. PurposeThe purpose of this prospective clinical trial was to evaluate a prefabricated telescopic retainer and a treatment protocol including the intraoral luting of a framework. Material and methodsA total of 23 participants (15 women and 8 men with a mean age of 61.6 ±2.9 years) were included. After 3 dropouts, 21 removable dentures (9 mandibular and 12 maxillary) retained by 91 delayed loaded Ankylos implants were investigated. All implants were restored with prefabricated conically shaped abutments (SynCone-abutment). The prefabricated corresponding cone matrix was assembled intraorally into a metal frame with autopolymerizing resin. After a loading period of 3 years, a follow-up examination investigated the fit of the framework, the prosthetic aftercare, the technical failures, and the retention force. A questionnaire was used to evaluate participant satisfaction. In addition, laboratory fabrication time and costs were compared with those of individually fabricated restorations. ResultsOne mandibular implant was lost after 25 months (survival rate, 98.9%). The removable dentures showed no apparent rocking and minimal prosthetic maintenance during the 36-month trial. No dentures required relining. The retention force was scored as good in 17 participants and high (with 6 implants in the maxilla) and low (with 2 implants in the mandible) in 2 participants each. No technical failures occurred. An assessment of laboratory fabrication time and costs revealed reduced time and costs. Patient satisfaction was significantly increased (P<.001) over the entire observation time. ConclusionsThe SynCone retainer presented a time- and cost-efficient treatment option with sufficient long-term retention for removable dentures and high patient satisfaction. Mandibular prostheses restored with 2 implants had limited success.

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

Statement of problemThe influence of the mandibular resorption profile on clinical outcome after converting a conventional complete denture into a Locator-retained implant overdenture is unknown. PurposeThe 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 methodsTwenty-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). ResultsOHIP-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. ConclusionsChanging a CD to an overdenture significantly improved ORLQoL regardless of the resorption degree, but heavily resorbed mandibles require more replacements of retention inserts.

Recommendations for implant-retained nasal prostheses after ablative tumor surgery: Minimal surgical aftercare, high implant survival, and satisfied patients.

Nasal defects resulting from tumor resection are preferably rehabilitated with implant-retained nasal prostheses. Aftercare, clinical outcome of the implants, and patients' satisfaction with implant-retained nasal prostheses were assessed. Twenty-eight consecutive patients needing total rhinectomy because of tumor resection between 1998 and 2013 were treated according to a standardized protocol with 2 implants in the nasal floor. Surgical and prosthetic aftercare was scored using patient records. Finally in 2014, skin reaction, peri-implant bone loss, and patients' satisfaction were assessed in all 13 still living patients. In total, 56 implants were inserted (median follow-up, 35.1 months; interquartile range [IQR], 8.9-63.3). Implant survival was 96.4%. Implant survival was independent of radiotherapy. Peri-implant skin was healthy and patients' satisfaction high. Longevity of the prostheses was limited. Rehabilitation of nasal defects resulting from total rhinectomy with implant-retained nasal prostheses, according to our protocol, resulted in high patient satisfaction and favorable treatment outcome. © 2015 Wiley Periodicals, Inc. Head Neck 38: E-E, 2016.

Clinical response of edentulous people treated with mini dental implants in nine dental practices

To analyse implant survival, prosthetic aftercare and quality of life (QoL) after stabilisation of complete dentures with mini-implants. Many edentulous patients refuse implant therapy due to the expenses and fear of surgery. Studies on minimally invasive and low-cost mini-implants remain rare. A total of 133 participating patients from nine private practices were evaluated via patient records, questionnaires and clinical examinations. Complications, maintenance, QoL questions and the German short version of the oral health impact profile (OHIP-G14) were analysed. After 7 to 61 months, 15 of 336 maxillary implants and 11 of 402 mandibular implants had to be removed. In addition, four mandibular implants experienced fracture. The difference between the 4-year survival rates of 94.3% for the maxilla and 95.7% for the mandible was not statistically significant (p = 0.581). All original 144 overdentures remained functional. The prosthetic interventions were typically limited to repairs of acrylic base fractures (about one in five patients), changes of plastic O-rings and relining procedures. The participants showed OHIP-G14 scores (median = 2) that were comparable with those of patients with overdentures retained by conventional implants. Mini-implant survival was similar to that of regular-diameter implants. Although some prosthetic aftercare was necessary, none of the overdentures had to be replaced. Prospective studies comparing conventional and mini-implants are warranted.

Retrievable, tooth-implant-supported, complete-arch fixed restorations in the maxilla: a 6-year retrospective study

The aim of this retrospective study was to evaluate the survival rate of implants, abutment teeth, and suprastructures along with the management of the complications for complete-arch, semipermanent cemented tooth-implant-supported restorations in 44 maxillae. Permanent cemented copings protect the prepared teeth from caries. The metal-ceramic fixed dental prostheses (FDPs) were cemented onto copings and implant abutments using acryl-urethane cement. Data were assessed via patient records and a final clinical examination. Six years after cementation, no implant or restoration had failed. After the extraction of two teeth and placement of an additional implant, three restorations had to be subsequently changed (89% of restorations were unchanged after 6 years). The loss of retention without tooth intrusion occurred in two restorations. All 23 restoration removals for prosthetic aftercare were non-destructive. The results of this study indicate that complete-arch, semipermanently cemented FDP rigidly connecting the maxillary teeth and implants are a reliable treatment option.

Care and Aftercare Related to Implant-Retained Dental Crowns in the Maxillary Aesthetic Region: A 5-Year Prospective Randomized Clinical Trial

To prospectively assess surgical and prosthetic care and aftercare related to the placement of implant-retained dental crowns after local bone augmentation in patients missing one tooth in the maxillary aesthetic region. Ninety-three patients were randomly allocated to one of three local augmentation groups: (1) chin bone; (2) chin bone covered by a Bio-Gide® membrane (Geistlich, Wolhusen, Switzerland); and (3) Bio-Oss® covered by a Bio-Gide® membrane. After local augmentation, implant placement (ITI) and fabrication of an implant-retained dental crown (cemented metal-ceramic dental crown) was performed. Prosthetic and surgical care and aftercare was scored from the first visit until 5 years after the augmentation of the implant region. The need for care and aftercare was comparable between the local augmentation groups. Three implants were lost (5-year implant survival rate: 96.7%). Surgical aftercare was needed in 9% of patients and consisted of care related to peri-implant tissue problems. Prosthetic aftercare was needed more often: all patients needed periodic routine inspections; 63% needed supplemental oral hygiene support; and 16% needed additional prosthetic care, mainly consisting of fabricating new crowns (12%). Placing an implant in the maxillary esthetic region after local bone augmentation is a safe and reliable treatment option not needing much specific aftercare other than periodic preventive routine inspections, routine oral hygiene care, and fabrication of a new crown in one out of every eight to nine patients in 5 years. The method used for augmentation was irrespective of the patients' need for aftercare.

Long-term prosthetic aftercare of direct vs. indirect attachment incorporation techniques to mandibular implant-supported overdenture

The aim of this long-term study was to compare the need for prosthetic aftercare of direct vs. indirect attachment incorporation techniques to mandibular implant-supported overdenture. Forty-five consecutive patients were included (130 implants were placed). Treatment was randomly allocated, resulting in 22 patients (group A) to be treated with direct ball attachment incorporation and 23 patients (group B) to be treated with indirect ball attachment incorporation. All patients were treated by experienced oral-maxillofacial surgeons/periodontists and experienced prosthodontists/residents. From the first day that the patients visited the clinic up to 20 years after the first treatment session, all surgical or prosthetic therapeutic interventions were recorded. The recorded data for the present study included the number of aftercare visits and dental treatment received (pressure sores relieve, liner changes due to loss of retention and attachment replacement due to wear). The mean follow-up was 93±57 months. No implants were lost. Statistical analysis revealed a statistically significantly (P<0.001) greater need for prosthetic interventions in group B vs. group A. The mean number of visits dedicated to - pressure sores relieve (7.04±1.4 vs. 3.63±0.84); liner exchange due to loss of retention (3.6±1.3 vs. 1.09±1.06) was significantly higher in group B. Attachment replacement due to wear occurred only in group B (11/23 - 47.8%). The direct technique for attachment incorporation in mandibular implant-supported overdentures using ball attachments is superior to the indirect technique from the aftercare perspective during a long-term evaluation period.

Mandibular overdentures supported by two Brånemark, IMZ or ITI implants: a ten‐year prospective randomized study

The aim of this prospective comparative study was to evaluate the survival rate, condition of peri-implant tissues, patient satisfaction and surgical and prosthetic aftercare of the IMZ-implant system (two-stage cylinder type), the Brånemark-implant system (two-stage screw type) and the ITI-implant system (one-stage screw type) supporting a mandibular overdenture during a 10-year follow-up period. Three groups of 30 edentulous patients were treated with two endosseous implants in the interforaminal region of the mandible. Clinical and radiographic parameters were evaluated immediately after completion of the prosthetic treatment and after 1, 5 and 10 years of functional loading. Prosthetic and surgical aftercare was scored during the evaluation period, as well as patient satisfaction. The 10-year survival rate was 93% for the IMZ group, 98% for the Brånemark group and 100% for the ITI group (IMZ<ITI, p<0.05). Mean marginal bone loss was limited over a period of 10 years. No differences in satisfaction and aftercare were observed between the groups. It is concluded that two implants placed in the interforaminal region, connected with a bar, supply a proper base for the support of a mandibular overdenture in the edentulous patient. After10 years, no relevant changes had developed between the three implant systems.

Mandibular overdentures supported by two or four endosseous implants: a 10‐year clinical trial

The aim of this 10-year clinical trial was to evaluate the treatment outcome (condition of hard and soft peri-implant tissues, patient satisfaction, surgical and prosthetic aftercare) of mandibular overdentures supported by two or four implants. Sixty edentulous patients with a mandibular height between 12 and 18 mm participated. Thirty patients were treated with an overdenture supported by two IMZ implants (group A) and 30 patients were treated with an overdenture supported by four IMZ implants (group B). Standardised clinical and radiographic parameters were evaluated 6 weeks after completion of the prosthetic treatment and after 1, 5 and 10 years of functional loading. Prosthetic and surgical aftercare was scored during the evaluation period, as well as patient satisfaction. There were no statistically significant differences with regard to any of the studied clinical or radiographic parameters of the peri-implant tissues between the groups. In addition, no differences in satisfaction and aftercare were observed between the groups. There is no difference in the clinical and radiographical state of patients treated with an overdenture on two or four implants during a 10-year evaluation period. Patients of both groups were evenly satisfied with their overdentures and received the same amount of aftercare. For reasons of cost-effectiveness, a two-implant overdenture is advised for patients with a Cawood classes IV-VI resorption of the mandible and complaints concerning retention and stability of the lower denture.

Long‐Term Evaluation of Hollow Screw and Hollow Cylinder Dental Implants: Clinical and Radiographic Results After 10 Years

In 1988, an implant manufacturer offered a new dental implant system, with a wide choice of hollow cylinder (HC) and hollow screw (HS) implants. The purpose of this retrospective study of HS and HC implants was to evaluate clinical and radiographic parameters of peri-implant tissue and to analyze surgical and prosthetic aftercare. A total of 89 HS and 26 HC implants in 38 edentulous patients were available for complete evaluation. The patients were treated with overdentures stabilized by two or four implants. The follow-up period was 10 years. The results of the clinical evaluation showed a mean sulcus probing depth of 3.3+/-1.3 mm (range=2 to 10 mm). The mean radiographic bone loss was 2.2+/-2.1 mm (range=0.1 to 12.2 mm). One implant (HS) was removed during the osseointegration period. Three other implants (two HS and one HC) in three patients had to be removed after 10 years. The survival rate of the HS implant (96.6%) was comparable to the HC implant (96.1%). The success rate of the HS implant (93.3%) was slightly more favorable compared to the HC implant (88.5%). The HS and HC implants met the Albrektsson criteria of success. HS and HC implants provide a stable base for long-term support of a mandibular overdenture. Furthermore, it is important to monitor peri-implant bone level by taking annual radiographs and measuring probing depth, especially after prolonged service.