Rehabilitation With Mandibular Implant-Retained Complete Overdenture Using the Association of Two Retention Systems.

This article reports a case of oral rehabilitation with two-implant-retained mandibular overdenture using bar/clip and ball attachment bilaterally on the distal side. A patient aged 69 years, fully edentulous, presented herself to private practice complaining about the instability of mandibular denture. Several possibilities of rehabilitation with advantages and disadvantages were explained to the patient, based in the clinical and radiograph examinations, and patient desire, in which she opted by conventional maxillary complete denture and two-implant-retained mandibular overdenture. Two external hexagon implants of 3.75 × 10 mm were placed in anterior area of mandible. The fabrication of the metal framework with bar/clip and ball attachment bilaterally on the distal side was planned based on prior arrangement of the artificial teeth. Internal adaptation and occlusal adjustments were performed in the day of insertion of finalized denture and instructions about maintenance and sanitation. The patient showed satisfaction with the final result of her treatment, and no complications were observed during this period. The association of bar/clip with ball system may be viable as option of retention for mandibular implant-retained complete overdenture; however, further randomized controlled trials are necessary to obtain detailed knowledge about the topic.

Changes in Bone Levels Around Mini-Implants in Edentulous Arches.

PURPOSE: To evaluate changes in marginal bone levels around maxillary and mandibular mini-implants stabilizing complete dentures and to explore possible risk factors associated with bone loss. MATERIALS AND METHODS: All eligible patients from nine private dental practices were invited to participate. Panoramic radiographs were obtained postoperatively and at the follow-up examination. The changes in bone level were estimated with linear mixed models that included the factors sex, age, jaw, region (anterior versus posterior), smoking habits, and loading concept. RESULTS: Of the 180 invited patients, 133 participated in the follow-up (response rate: 73.9%). Of 336 mini-implants in 54 maxillas and 402 mini-implants in 95 mandibles, 15 maxillary implants and 11 mandibular implants were lost after insertion, and 4 mandibular implants fractured. Radiographic evaluations in 11 participants were not possible. The mean marginal bone loss at the remaining 634 mini-implants in 122 patients was 0.8 mm in the maxilla and 0.5 mm in the mandible over a mean observation time of 2.2 ± 1.0 years. This difference in univariate estimation lost significance after adjusting for the other variables. Implants in former smokers showed more bone loss than implants in participants who had never smoked. Implants that were loaded 3 to 4 months after placement (delayed loading) showed more marginal bone loss than immediately loaded implants. No statistically significant differences were found between men and women, different age groups, or anterior and posterior implants. CONCLUSION: Mean marginal bone loss around mini-implants used to stabilize complete dentures was insignificantly higher in the maxilla than in the mandible after a mean observation period of 2.3 years. These values are comparable with marginal bone loss around standard-diameter implants. A previous smoking habit and delayed loading after implant placement with a low insertion torque were shown to be possible risk factors for bone loss.

A bar-retained overdenture as an external fixator device in a three-dimensional CAD/CAM-based surgical reconstruction of the mandible.

Large defects of the human face often cause esthetic as well as functional disorders. We present a new technique for reconstruction of the mandible with prosthodontic rehabilitation in a single surgery, using the implant-supported, bar-retained overdenture as an external fixator. A 58-year-old patient presented with a near total defect of the mandible after cancer resection. For rehabilitation, the mandibular condyles were virtually positioned in the centre of the fossae, and four dental implants were planned. The position of the fibula segments as well as their angulation and lengths were adapted to the implant position. To transfer this plan into surgery, a combined cutting/implant drilling guide was computer-aided printed. To provide the correct angulation of the fibula segments, a CAD/CAM dental arch-bar was made from titanium, fulfilling three functions: to bear the provisional prosthesis; to stabilize the molded fibula as an external fixator; and to position the complete fibula with the prosthesis in a correct relation to the upper jaw and occlusion, as indicated by the prosthesis. This innovative approach of combined prosthodontic and reconstructive rehabilitation could shorten the total reconstruction/rehabilitation time and avoid the need for additional extended surgeries.

Contemporary "All-on-4" concept.

Restoration of the atrophic edentulous maxilla and mandible with implant retained prostheses has involved the use of axially placed implants in regions of the maxilla and mandible based on the adequate availability of bone, often using a staged surgical approaches. Anatomic limitations including pneumatized maxillary sinus, proximity of the inferior alveolar nerve and lack of available native bone have many clinicians performing traditional grafting procedure prior to implant placement. Utilization of the "All-on-4" concept has overcome these anatomic restrictions by allowing placement of 2 vertical and 2 angled implants in the premaxilla and anterior mandible. This technique has enabled immediate placement of full arch fixed restoration at the time of implant surgery if sufficient torque is achieved. It has biomechanical advantages including increasing in A-P spread, enhancing load distribution with cross arch stabilization, shorten cantilever, longer implants to be placed by titling them posteriorly, and maintenance of marginal bone height. High implant survival rates of in the maxilla (92.5-100%), in the mandible (93-100%) and restoration (99.2-100%) prove that the "All-on-4" concept is a viable treatment option for edentulous patients with atrophic alveolar ridges circumventing these traditional grafting procedures.

Space requirement of a prefabricated bar on two interforaminal implants: a prospective clinical study.

OBJECTIVES: This clinical study measured the dimensional changes of existing lower complete dentures due to the integration of a prefabricated implant bar. Additionally, the impact of this dimensional change on patient satisfaction and oral function was analyzed. METHODS: Twenty edentulous patients (10 men/10 women; aged 65.9 ± 11.8 years) received two interforaminal implants. Subsequent to surgery, a chair side adapted, prefabricated bar (SFI Bar(®), C+M, Biel, Switzerland) was inserted, and the matrix was polymerized into the existing lower denture. The change of the denture's lingual dimension was recorded by means of a bicolored, silicone denture duplicate that was sectioned in the oro-vestibular direction in the regions of the symphysis (S) and the implants (I-left, I-right). On the sections, the dimensional increase was measured using a light microscope. Six months after bar insertion, patients answered a standardized questionnaire. RESULTS: All dentures exhibited increased lingual volume, more extensively at S than at I (P = 0.001). At S, the median diagonal size of the denture was doubled (+4.33 mm), and at I, the median increase was 50% (I-left/-right = +2.66/+2.62 mm). The original denture size influenced the volume increase (P = 0.024): smaller dentures led to a larger increase. The amount of denture increase did not have negative impact on either self-perceived oral function or patient satisfaction. Approximately, 95% of the patients were satisfied with the treatment results. CONCLUSIONS: The lingual size of a lower denture was enlarged by the integration of a prefabricated bar without any negative side effects. Thus, this attachment system is suitable to convert an existing full denture into an implant-supported overdenture.

Complete oral rehabilitation of a patient with hereditary gingival fibromatosis: a clinical report.

Hereditary gingival fibromatosis is a rare disease that has several debilitating oral and psychological manifestations, especially with young children and adolescents. The complexity of the treatment as well as the timing relative to the growth and maturation of the patient present a challenge. Few treatment options have been reported in the literature. This clinical report presents a multidisciplinary approach to treating a young patient with hereditary gingival fibromatosis by using implant-supported prostheses. The treatment steps and its outcome are discussed.

Immediate loading of mandibular overdentures supported by one-piece, direct metal laser sintering mini-implants: a short-term prospective clinical study.

BACKGROUND: Only a few studies have dealt with immediately loaded, unsplinted mini-implants supporting ball attachment-retained mandibular overdentures (ODs). The aim of this study is to evaluate treatment outcomes of ball attachment-retained mandibular ODs supported by one-piece, unsplinted, immediately loaded, direct metal laser sintering (DMLS) mini-implants. METHODS: Over a 4-year period (2009 to 2012), all patients referred to the Dental Clinic, University of Varese, and to a private practice for treatment with mandibular ODs were considered for inclusion in this study. Each patient received three or four DMLS mini-implants. Immediately after implant placement, a mandibular OD was connected to the implants. At each annual follow-up session, clinical and radiographic parameters were assessed, including the following outcome measures: 1) implant failures; 2) peri-implant marginal bone loss; and 3) complications. Statistical analysis was conducted using a life-table analysis. RESULTS: A total of 231 one-piece DMLS mini-implants were inserted in 62 patients. After 4 years of loading, six implants failed, giving an overall cumulative survival rate of 96.9%. The mean distance between the implant shoulder and the first visible bone-to-implant contact was 0.38 ± 0.25 and 0.62 ± 0.20 mm at the 1- and 4-year follow-up examinations, respectively. An incidence of 6.0% of biologic complications was reported; prosthetic complications were more frequent (12.9%). CONCLUSIONS: Within the limits of this study, it can be concluded that the immediate loading of one-piece, unsplinted, DMLS titanium mini-implants by means of ball attachment-supported mandibular ODs is a successful treatment procedure. Long-term follow-up studies are needed to confirm these results.

Assessment of Candida species colonization and denture-related stomatitis in bar- and locator-retained overdentures.

The aim of this study was to assess the prevalence of denture-related stomatitis (DRS) in different attachment-retained overdenture wearers and its association with particular colonizing Candida species. Thirty-seven edentulous patients with implant-supported maxillary or mandibular overdentures were enrolled. A full clinical history was obtained, including details of patients' oral hygiene practices and the levels of erythema based on Newton's classification scale. Swabs were taken from the palate and investigated mycologically to identify the yeast colonies. Quantitative and qualitative microbiological assessments were performed, which included recording the total numbers of colonies (cfu), their color, and their morphological characteristics. Significant differences were found in cfu values between the attachment and inner surfaces of locator- and bar-retained overdentures (P < .05). Candida albicans was the most common species in both evaluations, being isolated from 81.3% of bar-retained overdentures and 38.1% of locator-retained overdentures. DRS developed in all patients using bar-retained overdentures but in only 71.4% of those using locator-retained overdentures. No statistically significant relationship was found between bar and locator attachments according to smoking habit, overnight removal, or plaque and gingival indices (P > .05).

Incidence of peri-implant mucositis and peri-implantitis in edentulous patients with an implant-retained mandibular overdenture during a 10-year follow-up period.

OBJECTIVES: The aim of this sub-analysis of two prospective studies was to assess the incidence of peri-implant mucositis and peri-implantitis in fully edentulous patients with an implant-retained mandibular overdenture during a 10-year follow-up period. MATERIAL AND METHODS: One hundred and fifty edentulous patients with two endosseous implants to support a mandibular overdenture were available from two prospective studies. Clinical and radiographic parameters were assessed at 5 and 10 years of functional loading. Incidence of peri-implant mucositis and peri-implantitis were calculated at implant level and patient level following the Consensus of the Seventh European Workshop on Periodontology on peri-implant diseases. RESULTS: Incidence of peri-implant mucositis at patient level was 51.9% after 5 years of evaluation and 57.0% after 10 years. Incidence of peri-implantitis at patient level was 16.9% after 5 years of evaluation and 29.7% after 10 years. CONCLUSION: Peri-implant mucositis and peri-implantitis do occur in totally edentulous patients and incidence numbers are high.

Complete removable dental prosthesis with the swing lock system: a clinical report.

This clinical report describes the fabrication of a maxillary complete removable dental prosthesis with the swing lock system. The patient presented with large undercuts on the buccal and labial areas of the edentulous maxillary arch and a history of various failed alveoloplasty procedures that had attempted to remove the exostoses preventing denture insertion. The prosthodontic planning and treatment approach are discussed.

Immediate versus delayed loading of dental implants in edentulous patients' maxillae: a 6-year prospective study.

PURPOSE: This study compared the surgical protocol efficacy of immediate and delayed implant loading in edentulous maxillae opposed by natural or restored mandibular dentitions over an observational period of 6 years or longer. The selected outcome determinants included individual implant survival data, progressive measurements of peri-implant bone resorption, prosthodontic survival and success data, and report of complications. MATERIALS AND METHODS: A convenience sample of 49 patients requiring fixed implant-supported maxillary prostheses was split into two groups. The test group (34 patients) was treated according to the Columbus Bridge Protocol, which prescribes the insertion of four to six implants, including distally tilted implants, and load within 24 hours. The control group (15 patients) was treated via a two-stage surgical protocol of 6 to 9 straight implants that were loaded a mean 8.75 months after stage-one implant surgery. Two hundred sixty implants (test: n = 163, control: n = 97) were placed, and all subjects were ultimately treated with screw-retained full-arch prostheses. RESULTS: Two patients dropped out (one in the test group and one in the control group) by the time of the scheduled sixth annual visit. The other patients were followed up for 75.2 months (range: 72 to 90 months). At the 6-year follow-up, no differences in implant cumulative survival rates were found between groups. Significantly less bone loss was found in the test group (mean: 1.62 mm) compared with the control group (mean: 2.44 mm). All of the original prostheses were maintained throughout the study's observation period and were functioning satisfactorily at each patient's last recall appointment. CONCLUSION: Patients who received immediate and delayed implant loading in their edentulous maxillae demonstrated similar survival outcomes. However, less marginal bone loss was recorded around the immediately loaded implants over the study's 6-year follow-up period.

Overdentures on primary mandibular implants in patients with oral cancer: a follow-up study over 14 years.

We aimed to assess oral functioning, patients' satisfaction, condition of peri-implant tissues, and survival of implants up to 14 years after their insertion in patients with oral cancer who had had mandibular overdentures placed over primary implants. Endosseous dental implants were inserted prospectively in the interforaminal region of the mandible during resection of the tumour in 164/180 patients with oral cancer. All 58 patients were evaluated by questionnaires and clinical assessments during a final assessment in 2012. Implant-retained mandibular overdentures were inserted, and prosthetic rehabilitation and oral functioning were not associated with primary site or stage of the tumour, number or type of implants inserted, or the type of reconstruction. Over time the peri-implant mucosa was usually free of inflammation. More implants were lost in patients treated by radiotherapy (27/318, 8.5%) than in those not so treated (1/206, 0.5%). Patients who had been treated by irradiation reported more problems in oral functioning and less satisfaction than those who had not. Patients with an implant-retained mandibular overdenture reported fewer problems in oral functioning than patients without an overdenture. Primary insertion of an implant should be routinely incorporated in the surgical planning for patients with oral cancer, as oral functioning in those wearing mandibular overdentures improved considerably and peri-implant health was at least reasonable.

Periimplant bone-level reduction in relation to hydroxyapatite-coated dental implants that act as mandibular overdenture retainers: results at 6 to 10 years.

STATEMENT OF PROBLEM: Edentulism in combination with chronic alveolar ridge resorption can lead to a debilitating oral state which conventional complete dentures cannot alleviate. The provision of anterior mandibular implants positively contributes to both function and an improved quality of life for these patients. However, individuals who could most benefit from the treatment are usually older and more likely to have or develop serious health issues. PURPOSE: The purpose of the study was to assess the long-term success of one of the simpler implant treatments available and to consider the impact of a number of factors, including sex, age, health issues, and tobacco habits. This study also assessed the specific implant used, the Calcitek hydroxyapatite coated cylinder. MATERIAL AND METHODS: Forty-one patients who received 102 implants for mandibular overdenture retention from 1 operator between 1996 and 2002 were included in the study. Measurements were made from a series of radiographs to assess the effect of periimplant bone loss on surviving implants after a period of implant function of between 6 and 10 years. RESULTS: The loss of 1 implant lowered the survival rate to 99%. The overall annual bone loss observed was 0.16 mm/year. Individuals with a significant comorbidity exhibited a slight but significant increase in annual bone loss. CONCLUSIONS: The implant system in this study performed to an acceptable level in a mixed cohort of older individuals, including those with a serious comorbidity or tobacco habit.

An alternative solution for a complex prosthodontic problem: a modified Andrews fixed dental prosthesis.

This report describes the prosthodontic rehabilitation of an alveolar defect in the posterior mandible after the excision of an odontogenic myxoma. A minimally invasive technique that involves a modification of the traditional Andrews fixed dental prosthesis was used to replace both soft and hard tissues. The clinical stages and materials used to provide this treatment are discussed.

Microstrain around dental implants supporting fixed partial prostheses under axial and non-axial loading conditions, in vitro strain gauge analysis.

The current study used strain gauge analysis to perform an in vitro evaluation of the effect of axial and non-axial loading on implant-supported fixed partial prostheses, varying the implant placement configurations and the loading points. Three internal hexagon implants were embedded in the center of each polyurethane block with in-line and offset placements. Microunit abutments were connected to the implants using a torque of 20 N · cm, and plastic prosthetic cylinders were screwed onto the abutments, which received standard patterns cast in Co-Cr alloy (n = 10). Four strain gauges (SGs) were bonded onto the surfaces of the blocks, tangentially to the implants: SG 01 mesially to implant 1, SG 02 and SG 03 mesially and distally to implant 2, respectively, and SG 04 distally to implant 3. Each metallic structure was screwed onto the abutments using a 10-N·cm torque, and axial and non-axial loads of 30 kg were applied at 5 predetermined points. The data obtained from the strain gauge analyses were analyzed statistically through the repeated measures analysis of variance and the Tukey test, with a conventional level of significance of P < 0.05. The results showed a statistically significant difference for the loading point (P = 0.0001), with point E (nonaxial) generating the highest microstrain (327.67 µ[Latin Small Letter Open E]) and point A (axial) generating the smallest microstrain (208.93 µ[Latin Small Letter Open E]). No statistically significant difference was found for implant placement configuration (P = 0.856). It was concluded that the offset implant placement did not reduce the magnitude of microstrain around the implants under axial and non-axial loading conditions, although loading location did influence this magnitude.

Prosthodontic rehabilitation of a patient diagnosed with multiple idiopathic root resorption.

A female college student was referred by her general dentist for evaluation of the interproximal caries-like lesions discovered during her biannual visit. The lesions were determined to result from external resorption of unknown origin. After the most affected teeth had been extracted and the other teeth were restored after periodontal surgery, an interim partial removable dental prosthesis was placed. Two months later, the resorption pattern had proliferated to the rest of her dentition, thus revising the treatment plan to involve full mouth extractions and to place immediate maxillary and mandibular complete removable dental prostheses. Subsequently, 6 titanium dental implants were placed in each arch, and, after healing, opposing metal ceramic screw-retained fixed dental prostheses were inserted.

Prosthodontic rehabilitation of malpositioned implants after ameloblastoma followed by mandibulectomy and costal bone graft: a clinical report.

This clinical report describes the rehabilitation with costal bone graft reconstruction and 3 implants of a patient with a partial mandibular defect as a result of a partial mandibulectomy due to ameloblastoma of the left mandible. Due to the altered shape of the graft bone, the implants were malpositioned in the buccolingual plane. The prosthodontic rehabilitation was successfully completed by using an implant-supported milled bar combined with telescopic crown-retained dentures. This tooth implant-supported prosthesis successfully restored function and esthetics. Aspects that deal with the repair of the buccal soft tissues are discussed.

The influence of healing type on marginal bone levels of implants supporting mandibular overdentures: a randomized clinical study.

AIM: The aim of this study was to document the influence of healing type on the marginal bone loss around dental implants placed in the anterior mandible. MATERIALS AND METHODS: A total of 48 edentulous patients rehabilitated with 96 Astra Tech dental implants left to either submerged or nonsubmerged healing were included in the study group. The patients were examined in consecutive routine recall sessions six, 12, and 24 months after loading. The actual bone level measurements were performed by two independent examiners on panoramic X-rays, and the average of both examiners' calculations was used as the marginal bone level value. RESULTS: The marginal bone loss (MBL) of the implants at 6 months was found to be significantly higher in the submerged healing group (P< 0.05). No statistically significant relation was found between the MBL of implants left to submerged healing and that of implants left to non-submerged healing in the other follow-up periods. CONCLUSION: In situations where the dental implant has good primary stability, non-submerged healing can be recommended to avoid a second surgery for healing abutment connection.

Provision of a swing lock denture for a patient with Gorlin Goltz syndrome.

Swinglock dentures are used relatively infrequently but in cases of compromised anatomy or where the pattern of tooth loss is unfavourable, they provide a useful removable partial denture design option. The aim of this article is to provide a clear summary of the clinical and technical considerations necessary when providing a Swinglock denture.

Immediate rehabilitation of the edentulous mandible using Ankylos SynCone telescopic copings and intraoral welding: a pilot study.

The aim of this prospective study was to assess the suitability of immediate rehabilitation of the edentulous mandible using SynCone copings and the intraoral welding technique. Patients with an edentulous mandible were fitted with a removable restoration supported by an intraorally welded titanium bar. Copings were connected to their respective SynCone 5-degree abutments and then welded to a titanium bar using an intraoral welding unit. This framework was used to support the definitive restoration, which was delivered on the day of implant placement. Restoration success and survival, implant success, and biologic or technical complications were assessed immediately after surgery and at 6 and 12 months. Twenty-two patients were consecutively treated with 88 immediately loaded implants. No acrylic resin fractures or radiographically detectable alterations of the welded frameworks were present in the 22 restorations delivered. One implant (1.1%) failed 1 month after surgery; all remaining implants (98.9%) were clinically stable at the 12-month follow-up. Within its limitations, this pilot study demonstrated that it is possible to successfully rehabilitate the edentulous mandible on the day of surgery with a definitive restoration supported by an intraorally welded titanium framework and SynCone 5-degree abutments.