Frailty and mini dental implants.

Patients who have been diagnosed as frail and have atrochic jaws may have a dramatic increase of quality of life with mini implant treatment for retention of a mandibular complete denture.

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.

Bone thickness and height of the buccal shelf area and the mandibular canal position for miniscrew insertion in patients with different vertical facial patterns, age, and sex.

OBJECTIVES: The objectives of this article were the following: (1) to analyze bone thickness and height (BTH) of the buccal shelf area (BS) quantitatively in four different potentially eligible sites for miniscrew insertion; (2) to compare and contrast BTH and the changes in spatial position of the inferior alveolar nerve canal (IANC); and (3) to assess differences with age among vertical facial patterns (hypodivergent, normodivergent, and hyperdivergent) and well as by sex. MATERIALS AND METHODS: Cone-beam computed tomography scans of 205 individuals (110 women and 95 men) were divided into groups according to age, vertical facial pattern, and sex. The BTH of the BS and the BTH to the IANC were measured in the mesial and distal roots of the first and second molars. RESULTS: BTH progressively increased in a posterior direction (P < .001), while BTH to the IANC increased and decreased (P < .001) for thickness and height, respectively, in the same direction in all age groups, for the three different vertical facial patterns, and in both sexes. Women showed significantly less BTH to the IANC (P < .002). Hypodivergent patients had greater BTH (P < .024) and a smaller bone height to the IANC (P < .018) only in the first molar region. Patients over 40 years of age had lower bone height in the second molar area (P < .003). CONCLUSIONS: The ideal place for BS miniscrew insertion is the region of the distal root of the second molars, regardless of facial pattern, sex, and age. The BS in women has less BTH and less BTH to the IANC.

Comparative clinical study of conventional dental implant and mini dental implant-retained mandibular overdenture: A 5- to 8-Year prospective clinical outcomes in a previous randomized clinical trial.

AIM: To compare the long-term prospective clinical outcomes in a previous randomized controlled clinical trial (RCT) of 2 Mini Dental Implant (2MDI), 4 Mini Dental Implant (4MDI), and 2 Conventional Dental Implant (2CDI)-retained mandibular overdenture with follow-up between 5 to 8 years. MATERIALS AND METHODS: Thirty-seven patients formerly participated in the Comparative Clinical Study of CDI and MDI for Mandibular Overdenture were requested for examination of clinical outcomes. A total of 104 implants were placed with mean follow-up periods 6.64 ± 0.60 years. In Group 1 (2MDI) and Group 2 (4MDI), implants were placed and immediately loaded with Equator® attachments to retained mandibular overdenture. In Group 3 (2CDI), implants were placed and delayed 3 months for denture loading with ball attachment. The success rate, survival rate, clinical implant performance scale (CIP scale), peri-implant tissue status, prosthetic complication, implant stability quotient (ISQ), marginal bone level change (MBLC), and patient satisfactions were analyzed. RESULTS: After 5 to 8 years follow-up, the success rate in Groups 1, 2, and 3 were 90.91%, 93.33%, and 54.55%, respectively. The success rate in Group 3 was significantly lesser than Group 1 (p = 0.016) and Group 2 (p < 0.001). The survival rate in Groups 1, 2, and 3 was 100%, 96.67%, and 90.91%, respectively, and showed no significant differences. Mean ISQ reported no significant differences between groups. Mean MBLC were 0.57 ± 1.19 mm, 0.68 ± 0.90 mm, and 1.55 ± 1.60 mm in Groups 1, 2, and 3, respectively. Group 3 reported significantly greater mean MBLC than Group 1 (p = 0.016) and Group 2 (p = 0.011), but Groups 1 and 2 were not significantly differences. The overall patient satisfactions were reported as not significant differences between groups. CONCLUDE: Two MDI-retained mandibular overdentures with immediate loaded protocol performed had favorable clinical outcomes, cost effectiveness, and overall patient satisfactions after 5 to 8 years follow-up.

Influence of marginal bone resorption on two mini implant-retained mandibular overdenture: An in vitro study.

PURPOSE: To investigate the biomechanical effect of marginal bone resorption (MBR) on the mandibular mini implant (MI)-retained overdenture (MI-OD) on the edentulous model. MATERIALS AND METHODS: The experimental mandibular edentulous model was modified from a commercial model with 2 mm thick artificial soft tissue under denture base. Two MIs (Φ2.6 mm × 10 mm) were bilaterally placed between the lateral incisor and the canine area and attached with magnetic attachments. Three groups were set up as follows: 1) alveolar bone around the MI without MBR (normal group), 2) with MBR to 1/2 the length of the implant (resorption group), and 3) complete denture (CD) without MI (CD group). Strain around the MI, pressure near the first molar area, and displacement of denture were simultaneously measured, loading up to 50 N under bilateral/unilateral loading. Statistical analysis was performed using independent-samples t test and one-way ANOVA (α=.05). RESULTS: The strain around the MI with MBR was approximately 1.5 times higher than that without MBR. The pressure in CD was higher than in MI-ODs (P <.05), while there was no statistical difference between the normal and resorption group (P >.05). Similarly, the CD demonstrated a greater displacement of the denture base than did the MI-ODs during bilateral and unilateral loadings (P <.05). CONCLUSION: The strain around the MI with MBR was approximately 1.5 times higher than that without MBR. The pressure on posterior alveolar ridge and denture displacement of MI-ODs significantly decreased compared to CDs, even when MBR occurs. Bilateral balanced occlusion was recommended for MI-ODs, especially when MBR occurred.

Computerised occlusal analysis of mini-dental implant-retained mandibular overdentures: A 1-year prospective clinical study.

Occlusal analysis is a substantial tool for the functional improvement evaluation after using implant-retained overdenture comparing to complete denture without dental implant retaining. To evaluate occlusal pattern, chewing force distribution in mini-dental implant-retained mandibular overdentures by computerised occlusal analysis system and to compare patient satisfaction after 1-year function. Thirty-one patients wearing complete dentures were included in the study. Prior to mini-dental implant-retained treatment, all patients were assessed for occlusion and force distribution using computerised occlusal analysis system (T-Scan® ), and then, all patients received two mini-dental implant-retained mandibular overdentures. Mini-dental implants were immediately loaded using low vertical profile attachments (Equator® ). T-Scan® was used to evaluate chewing force and force distribution at 1 day, 3 months, 6 months and 12 months. The patient satisfactions before implant placement and after 1 year were evaluated using questionnaires which included satisfaction of denture quality, psychosocial behaviour and chewing efficiency modified from the validated questionnaires. Clinical evaluation of two mini-dental implant-retained mandibular overdentures showed 100% success rate after 1 year. T-Scan® demonstrated that maximum occlusal contact force increased continuously. The force distribution; the tooth contact number increased over the period. At 1-year follow-up, overall patient satisfaction was significantly greater than before receiving mini-dental implant treatment (P < .001). Using computerised occlusal analysis, mini-dental implants improve complete denture function significantly in terms of maximum occlusal contact force, tooth contact number without the impairment of force distribution. The oral function of the patients has been enhanced.

Mini-dental implants for definitive prosthesis retention - A synopsis of the current evidence.

Background: This narrative review provides an evidence-based overview of the comparison between mini-dental implants (MDI) and conventional dental implants for definitive prosthesis retention. In addition, recommendations are made on whether the use of reduced diameter dental implants is more appropriate. Method: A literature review was conducted via electronic search addressing the following topics: (1) osseointegration, (2) peri-implant soft tissue characteristics, (3) biomechanics, (4) implant survival and (5) implant success. Conclusion: The procedure for dental implant prosthetic rehabilitation should preferentially include conventional dental implants (i.e. [Formula: see text][Formula: see text]mm fixture diameter). Small (3-3.25[Formula: see text]mm) and narrow (3.3-3.5[Formula: see text]mm) dental implants should primarily be used in non-load-bearing regions. MDI ([Formula: see text][Formula: see text]mm) should be considered to retain definitive prosthesis, only for reasons of anatomy or patient-centred preferences and as a last resort. If MDI are to be used, patients should be made aware of the lack of long-term, high-quality evidence as a part of the informed consent process and that most of the prospective data available pertain to MDI retaining complete dentures.

Fracture Strength and Osseointegration of an Ultrafine-Grained Titanium Mini Dental Implant after Macromorphology Optimization.

The aim of this in vitro and in vivo study was to evaluate the fracture strength and osseointegration of an ultrafine-grained pure titanium (UFG-Ti) mini dental implant, prepared by equal channel angular pressing (ECAP) after macro-morphology optimization. UFG-Ti was prepared by ECAP using four passes in route Bc with the internal channel angle of 120° at room temperature. Furthermore, its microstructure and mechanical properties were studied. In optimization, a three-dimensional finite element model (FEM) composed of an UFG-Ti mini implant and alveolar bone was established to improve the implant surface area and decrease the stress distribution. Then, optimized mini implants were fabricated using UFG-Ti, and a fracture strength test was performed. For the in vivo study, UFG-Ti mini implants were inserted into rabbit femurs. A histological assessment and a pull-out test were performed to evaluate its osseointegration ability. The results show that the ultimate tensile strength of UFG-Ti (685 ± 35 MPa) was significantly higher than that of commercial pure titanium (CP-Ti grade 4, 454 ± 27 MPa). After optimization, the surface area of the 2.5 mm diameter mini implant was 19% higher than that of the standard-thread mini implant, and the maximum equivalent stress (Max EQV stress) decreased by 28% in cortical bone and by 33.1% in cancellous bone, when the thread height was 0.3 mm and the pitch was 0.67 mm. The fracture strength of the UFG-Ti mini implants (328 ± 21 N) was significantly higher than that of CP-Ti grade 4 mini implants (197 ± 11 N). The in vivo study showed favorable osseointegration in both the UFG-Ti and CP-Ti groups, but the osseointegration strength of the optimized mini implants was higher than that of the standard-thread mini implants. In conclusion, the fracture and osseointegration strength had been significantly improved for UFG-Ti mini dental implant after optimization. The excellent mechanical properties and osseointegration of the UFG-Ti mini implant suggest its feasibility for clinical application.

Mini Dental Implant-Retained Removable Partial Dentures: Treatment Effect Size and 6-Months Follow-up.

OBJECTIVE: The aim was to compare esthetic outcomes, masticatory performance and a comfort of removable partial denture (RPD) wearing after receiving: clasp-retained RPD (C-RPD) or mini dental implant-retained RPD (MDI-RPD) in the mandible. MATERIALS AND METHODS: A sample of 88 patients (Kennedy Class I) with all posterior teeth missing and a linear support for a RPD participated. A total of 52 patients (36 females, 16 males; 56 to 84 years old) participated in the C-RPD group and 36 patients (26 females, 10 males; 43 to 81 years old) in the MDI-RPD group. All MDIs were placed adjacent to the last remaining mandibular anterior tooth or one tooth length posteriorly. The new RPDs had Co-Cr frameworks with lingual plate major connectors; the MDI-RPDs were retained by O-ball matrices and the C-RPDs with clasps. Patients answered questions at pre-treatment and post-treatment stages and after 6-months follow-up: how satisfied they had been with esthetic appearance, how confident they were while chewing hard food, how satisfied they were with food comminution and they also evaluated a comfort of RPD wearing. The 0-10 visual-analogue scale was used. Statistics included descriptive methods, t-tests and the standardized effect-size calculation. RESULTS: The MDI-RPD wearers were more satisfied with their post-treatment esthetics, food comminution, a comfort with RPDs and had better confidence while chewing than the C-RPD wearers. The MDI-RPD wearers reported larger positive effect of the treatment. The results were consistent throughout the first 6-months period. CONCLUSION: The MDI-RPD patients showed superior outcomes than the C-RPD patients after the treatment and over the 6-month period.

Comparison of immediate-load mini dental implants and conventional-size dental implants to retain mandibular Kennedy class I removable partial dentures: A randomized clinical trial.

BACKGROUND: Complications of distal extension mandibular removable partial dentures are: loss of retention, irritation, and so forth. Dental implants have been used to support distal extension removable partial dentures. However, many patients have limited bone support in which to place conventional-size dental implants. PURPOSE: To compare the clinical outcomes of using immediate-loaded mini dental implants and immediate-loaded conventional-size dental implants, when used to retain mandibular Kennedy class I removable partial dentures. MATERIALS AND METHODS: Thirty patients were randomly divided into two groups. Mini dental implants and conventional-size dental implants were placed in participants in the first molar region on both sides. The dentures were connected immediately. Patients were recalled on 1, 3, 6, and 12 months after surgery. Digital periapical radiographs were made, and patient satisfaction was recorded. Data were analyzed by independent samples t-test and paired samples t-test (P = .05). RESULTS: Twenty eight of the implants survived (survival rate = 93.3%) in each group. Mean radiographic bone loss was 0.47 ± 0.42 and 1.03 ± 1.07 mm in groups 1 and 2, respectively. Conventional-size implants revealed significantly greater marginal bone loss than mini implants (P = .01). Patient satisfaction showed significant improvement after treatment in both groups. CONCLUSIONS: Immediate-loaded mini dental implants can be applied for retaining mandibular Kennedy class I removable partial dentures with very favorable results.

Effects of different numbers of mini-dental implants on alveolar ridge strain distribution under mandibular implant-retained overdentures.

PURPOSE: To investigate the strains around mini-dental implants (MDIs) and retromolar edentulous areas when using different numbers of MDIs in order to retain mandibular overdentures. MATERIALS AND METHODS: Four different prosthetic situations were fabricated on an edentulous mandibular model including a complete denture (CD), and three overdentures, retained by four, three or two MDIs in the interforaminal region with retentive attachments. A static load of 200N was applied on the posterior teeth of the dentures under bilateral or unilateral loading conditions. The strains at the mesial and distal of the MDIs and the retromolar edentulous ridges were measured using twelve strain gauges. Comparisons of the mean microstrains among all strain gauges in all situations were analyzed. RESULTS: The strain distribution determined during bilateral loading experienced a symmetrical distribution; while during unilateral loading, the recorded strains tended to change from compressive strains on the loaded side to tensile strains. Overall, the number of MDIs was found to be passively correlated to the generated compressive strain. The highest strains were recorded in the four MDIs followed by three, two MDIs retained overdenture and CD situations, respectively. The highest strain was found around the terminal MDI. CONCLUSIONS: The use of a low number of MDIs tends to produce low strain values in the retromolar denture-bearing area and around the terminal MDIs during posterior loadings. However, when using a high number of MDIs, the overdenture tends to have more stability during function.

New mini dental implant attachments versus O-ring attachment after cyclic aging: Analysis of retention strength and gap space.

Overdenture as a treatment modality for both partially and fully edentulous patients is costeffective and less expensive. The purpose of the present study was to examine the newly fabricated attachments by comparing them with conventional O-ring attachment in vitro in terms of retention force and cyclic aging resistance. A total of 150 samples were prepared and divided into five groups according to the materials used (O-ring attachment, Deflex M10 XR, Deflex Classic SR, Deflex Acrilato FD, and flexible acrylic resin). The retention force of different attachments was measured by a mini dental implant after three subsequent aging (0, 63, and 126) cycles in the circumstances similar to the oral environment. The gap space between the head of the implant and the inner surface of the attachments was detected. Two-way analysis of variance (ANOVA) analysis with multiple comparisons test was applied for statistical analysis. The results showed that Deflex M10 XR had the highest retention force and the lowest gap space after cyclic aging; in addition, by comparing the relative force reduction, the lowest values were obtained in the O-ring attachment and the highest values in the flexible acrylic resin attachment. The retention force measured after cyclic aging for the Deflex M10 XR attachment was greatly improved when compared with the O-ring attachment and other types of attachment materials; in addition, the Deflex M10 XR attachment exhibited the minimum gap space between the inner surface and the mini dental implant head. In conclusion, Deflex M10 XR has the ability to withstand weathering conditions and retains its durable and retentive properties after aging when compared with other attachments.

Osseointegration of standard and mini dental implants: a histomorphometric comparison.

BACKGROUND: Mini dental implants (MDIs) are becoming increasingly popular for rehabilitation of edentulous patients because of their several advantages. However, there is a lack of evidence on the osseointegration potential of the MDIs. The objective of the study was to histomorphometrically evaluate and compare bone apposition on the surface of MDIs and standard implants in a rabbit model. METHODS: Nine New Zealand white rabbits were used for the study to meet statistical criteria for adequate power. Total 18 3M™ESPE™ MDIs and 18 standard implants (Ankylos® Friadent, Dentsply) were inserted randomly into the tibia of rabbits (four implants per rabbit); animals were sacrificed after a 6-week healing period. The specimens were retrieved en bloc and preserved in 10% formaldehyde solution. Specimens were prepared for embedding in a light cure acrylic resin (Technovit 9100). The most central sagittal histological sections (30-40 µm thick) were obtained using a Leica SP 1600 saw microtome. After staining, the Leica DM2000 microscope was used, the images were captured using Olympus DP72 camera and associated software. Bone implant contact (BIC) was measured using Infinity Analyze software. RESULTS: All implants were osseointegrated. Histologic measures show mineralized bone matrix in intimate contact with the implant surface in both groups. The median BIC was 57.5% (IQR 9.0) in the MDI group and 55.0% (IQR 4.5) in the control group (P > 0.05, Mann-Whitney test). There were no statistical differences in osseointegration at 6 weeks between MDIs and standard implants in rabbit tibias. CONCLUSIONS: Based on these results, it is concluded that osseointegration of MDIs is similar to that of standard implants.

Small-Diameter Implants: A 7-Year Retrospective Study.

Oral implantology has become a major discipline within the field of dentistry. Small or mini dental implants have demonstrated success in the retention of removable and fixed prostheses. Small-diameter implants (SDI) and mini-diameter implants (MDI) describe a group of implants that demonstrate a diameter less than 3 mm. This retrospective study reports on 335 SDI placed during a 7-year period. All implants were placed in healed sites (>6 months) and loaded immediately or after waiting 3 months. A total of 321 implants were restored and functional within the study's time interval. A total of 14 implants failed, resulting in a 96.1% implant success rate. Treatment plan considerations should include prosthetic design, specific arch, and immediate load. Overall, SDI can be utilized as an alternative implant treatment option for patients with atrophic bone, compromised medical histories and financial constraints.

Comparative Clinical Study of Conventional Dental Implants and Mini Dental Implants for Mandibular Overdentures: A Randomized Clinical Trial.

BACKGROUND: Dental implant-retained overdentures have been chosen as the treatment of choice for complete mandibular removable dentures. Dental implants, such as mini dental implants, and components for retaining overdentures, are commercially available. However, comparative clinical studies comparing mini dental implants and conventional dental implants using different attachment for implant-retained overdentures have not been well documented. PURPOSE: To compare the clinical outcomes of using two mini dental implants with Equator® attachments, four mini dental implants with Equator attachments, or two conventional dental implants with ball attachments, by means of a randomized clinical trial. MATERIALS AND METHODS: Sixty patients received implant-retained mandibular overdentures in the interforaminal region. The patients were divided into three groups. In Groups 1 and 2, two and four mini dental implants, respectively, were placed and immediately loaded by overdentures, using Equator® attachments. In Group 3, conventional implants were placed. After osseointegration, the implants were loaded by overdentures, using ball attachments. The study distribution was randomized and double-blinded. Outcome measures included changes in radiological peri-implant bone level from surgery to 12 months postinsertion, prosthodontic complications and patient satisfaction. RESULTS: The cumulative survival rate in the three clinical groups after one year was 100%. There was no significant difference (p < 0.05) in clinical results regarding the number (two or four) of mini dental implants with Equator attachments. However, there was a significant difference in marginal bone loss and patient satisfaction between those receiving mini dental implants with Equator attachments and conventional dental implants with ball attachments. The marginal bone resorption in Group 3 was significantly higher than in Groups 1 and 2 (p < 0.05); there were no significant differences between Groups 1 and 2. There was no significant difference in patient satisfaction between Groups 1 and 2 but it was significantly higher than that in Group3 (p < 0.05). CONCLUSIONS: Two and four mini dental implants can be immediately used successfully for retaining lower complete dentures, as shown after a 1-year follow up.

New Mini Dental Implant Attachments versus O-ring Attachment after Cyclic Aging: Analysis of Retention Strength and Gap Space / 华中科技大学学报（医学）（英德文版）

Overdenture as a treatment modality for both partially and fully edentulous patients is costeffective and less expensive.The purpose of the present study was to examine the newly fabricated attachments by comparing them with conventional O-ring attachment in vitro in terms of retention force and cyclic aging resistance.A total of 150 samples were prepared and divided into five groups according to the materials used (O-ring attachment,Deflex M10 XR,Deflex Classic SR,Deflex Acrilato FD,and flexible acrylic resin).The retention force of different attachments was measured by a mini dental implant after three subsequent aging (0,63,and 126) cycles in the circumstances similar to the oral environment.The gap space between the head of the implant and the inner surface of the attachments was detected.Two-way analysis of variance (ANOVA) analysis with multiple comparisons test was applied for statistical analysis.The results showed that Deflex M10 XR had the highest retention force and the lowest gap space after cyclic aging;in addition,by comparing the relative force reduction,the lowest values were obtained in the O-ring attachment and the highest values in the flexible acrylic resin attachment.The retention force measured after cyclic aging for the Deflex M10 XR attachment was greatly improved when compared with the O-ring attachment and other types of attachment materials;in addition,the Deflex M10 XR attachment exhibited the minimum gap space between the inner surface and the mini dental implant head.In conclusion,Deflex M10 XR has the ability to withstand weathering conditions and retains its durable and retentive properties after aging when compared with other attachments.

Immediate versus delayed loading of strategic mini dental implants for the stabilization of partial removable dental prostheses: a patient cluster randomized, parallel-group 3-year trial.

BACKGROUND: Acceptable short-term survival rates (>90 %) of mini-implants (diameter < 3.0 mm) are only documented for mandibular overdentures. Sound data for mini-implants as strategic abutments for a better retention of partial removable dental prosthesis (PRDP) are not available. METHODS/DESIGN: The purpose of this study is to test the hypothesis that immediately loaded mini-implants show more bone loss and less success than strategic mini-implants with delayed loading. In this four-center (one university hospital, three dental practices in Germany), parallel-group, controlled clinical trial, which is cluster randomized on patient level, a total of 80 partially edentulous patients with unfavourable number and distribution of remaining abutment teeth in at least one jaw will receive supplementary min-implants to stabilize their PRDP. The mini-implant are either immediately loaded after implant placement (test group) or delayed after four months (control group). Follow-up of the patients will be performed for 36 months. The primary outcome is the radiographic bone level changes at implants. The secondary outcome is the implant success as a composite variable. Tertiary outcomes include clinical, subjective (quality of life, satisfaction, chewing ability) and dental or technical complications. DISCUSSION: Strategic implants under an existing PRDP are only documented for standard-diameter implants. Mini-implants could be a minimal invasive and low cost solution for this treatment modality. TRIAL REGISTRATION: The trial is registered at Deutsches Register Klinischer Studien (German register of clinical trials) under DRKS-ID: DRKS00007589 ( www.germanctr.de ) on January 13(th), 2015.

Mechanical response comparison in an implant overdenture retained by ball attachments on conventional regular and mini dental implants: a finite element analysis.

This study investigates the bone/implant mechanical responses in an implant overdenture retained by ball attachments on two conventional regular dental implants (RDI) and four mini dental implants (MDI) using finite element (FE) analysis. Two FE models of overdentures retained by RDIs and MDIs for a mandibular edentulous patient with validation within 6% variation errors were constructed by integrating CT images and CAD system. Bone grafting resulted in 2 mm thickness at the buccal side constructed for the RDIs-supported model to mimic the bone augmentation condition for the atrophic alveolar ridge. Nonlinear hyperelastic material and frictional contact element were used to simulate characteristic of the ball attachment-retained overdentures. The results showed that a denture supported by MDIs presented higher surrounding bone strains than those supported by RDIs under different load conditions. Maximum bone micro strains were up to 6437/2987 and 13323/5856 for MDIs/RDIs under single centric and lateral contacts, respectively. Corresponding values were 4429/2579 and 9557/5774 under multi- centric and lateral contacts, respectively. Bone micro strains increased 2.06 and 1.96-folds under single contact, 2.16 and 2.24-folds under multiple contacts for MDIs and RDIs when lateral to axial loads were compared. The maximum RDIs and MDIs implant stresses in all simulated cases were found by far lower than their yield strength. Overdentures retained using ball attachments on MDIs in poor edentulous bone structure increase the surrounding bone strain over the critical value, thereby damaging the bone when compared to the RDIs. Eliminating the occlusal single contact and oblique load of an implant-retained overdenture reduces the risk for failure.

Insertion Torque of Mini Dental Implants and their Failure Risk after Immediate Loading / Torque de Inserción de Mini Implantes Dentales y su Riesgo de Fracaso cuando son Cargados Inmediatamente

A minimum insertion torque has been suggested for immediate function of regular diameter implants. Even when there is a growing tendency to use Mini Dental Implants (MDIs) for immediate function of dentures, there is no clinical data concerning MDIs insertion torque, nor its influence on implant failure. The aim of this prospective study was to assess the insertion torque of immediate loaded MDIs in edentulous patients and its association with risk failure. Ninety MDIs were placed in the anterior mandible of 45 edentulous patients, two per patient. The insertion torque was recorded with an electronic device and failures were documented during two years follow-up. All implants were immediately loaded with overdentures, using ball (44/90) or bar (46/90) attachments. A Kaplan­Meier survival probability estimator and a fitted multiple Cox regression model were performed to establish the influence of insertion torque and other clinical parameters on implant risk failure. The average insertion torque of 90 MDIs was 12.5±7.8 Ncm. A cumulative survival rate of 94.2% (5/90) was found by means of the Kaplan-Meier estimation. The Cox proportional-hazards regression model showed no association between insertion torque and MDIs failure. MDIs have much lower insertion torque than average conventional implants. The insertion torque of MDIs immediately loaded with mandibular dentures, seems not to be a risk factor associated to failure, at two years follow-up.

Un mínimo torque de inserción ha sido sugerido para realizar carga inmediata de implantes de diámetro regular. Aún cuando existe una tendencia creciente a utilizar Mini Implantes Dentales (MID) para la función inmediata de las prótesis totales, no hay datos clínicos relativos a los valores de torque de inserción de estos, ni tampoco de su influencia en el fracaso del implante. El objetivo de este estudio prospectivo fue evaluar el torque de inserción de mini implantes dentales con carga inmediata en pacientes desdentados y su asociación con el riesgo de fracaso. Noventa MIDs fueron colocados en la mandíbula anterior de 45 pacientes desdentados, dos por paciente. El torque de inserción fue obtenido con un dispositivo electrónico y los fracasos fueron documentadas a dos años de seguimiento. Todos los implantes fueron cargados inmediatamente con sobredentaduras, usando un sistema de retención de bola (44/90) o barra (46/90). Se utilizó el estimador de probabilidad de sobrevida de Kaplan-Meier y el modelo riesgos proporcionales de Cox ajustado para establecer la influencia de torque de inserción y otros parámetros clínicos sobre el riesgo de fracaso del implante. El promedio de torque de inserción de 90 MIDs fue 12,5±7,8 Ncm . Los MIDs mostraron a través de la estimación de Kaplan-Meier, una tasa de supervivencia acumulada de 94,2% (5/90). El modelo de riesgos proporcionales de Cox reveló que no existe asociación entre el valor de torque de inserción y el fracaso MIDs. MIDs tienen un valor de torque de inserción mucho más bajo que los implantes convencionales. El torque de inserción de MIDs cargados inmediatamente con prótesis mandibulares, no parece ser un factor de riesgo asociado al fracaso, a dos años de seguimiento.

Prosthodontic management of flat mandibular ridge by mini implant supported over denture.

Loosening of lower denture has always been a common complaint of denture wearer, particularly in case of severe bone resorption. Various treatment modalities including preprosthetic surgery or ridge augmentation therapy to improve the ridge height and conventional implant treatments are available. But many patients are not willing to undergo through such extensive surgical procedure or conventional twin stage implant therapy owing to the chronic old age ailment and cost factor. So mini implant (SENDAX MDI) supported over denture is a boon for them who want a quick and minimally invasive solution, with a much lower cost. In this article we shall discuss the case report of a 60-year-old female patient with atropic mandibular ridge rehabilitated with MDI, (mini dental implant), Sendax mini implant.