Locator Attachments Research Articles

Two implant-retained mandibular overdenture using locator attachment – A clinical report

Success rates for osseointegrated dental implants in the anterior mandible are very high. Due to these success rates, as well as lower costs, it is common to treat edentulous patients with just two implants, which will act as anchors for retention of the overdenture. The implant-retained overdenture is an alternative treatment option in edentulous patient's rehabilitation, providing significant retention, stability, function, and esthetics. This clinical report highlights the prosthetic rehabilitation of a partially edentulous mandibular arch with implant-supported overdenture using locator attachment.

Effect of different means of retention on single midline implant supporting mandibular overdenture

Purpose: This study was conducted to evaluate the effect of locator attachment versus retention silicone lining material on the supporting structure of a single midline implant supporting mandibular overdenture and retention of the prosthesis. Methods: Sixteen patients with completely edentulous mandibles were selected for this study and divided into two groups. In all patients, a single implant was placed at midline area after cone beam radiography was performed. Group I was retained with locator attachment, while Group II was retained with silicone material. Follow-up was carried out at denture insertion, six months and 12 months following insertion. Peri-implant bone loss as well as posterior bone loss was evaluated using cone beam computerized tomography and retention was evaluated using forcemeter device and wire hook attaches to the prosthesis. Results: There was a statistically significant difference in peri-implant bone loss between the two groups during the 2nd follow up period (P ≤0.05). There was a statistically significant difference in periimplant bone loss between the two groups at the 2nd follow up period and at the end of the study period (P≤ 0.05). There was no statistically significant difference in posterior bone loss between the two studied groups (P ≤ 0.05) and regarding retention there was no statistically significant difference between the two groups along the follow up periods. Conclusion: From the results obtained from this study, it could be concluded that locator attachment showed lower peri-implant bone loss than Retention. Silicone material in the overall follow-up period with a statistically significant difference. This was attributed to the decrease in the effect of the resiliency of attachments and Silicone over time, and the more permanent effect of locator attachment.

Comparison of retentive force and wear pattern of Locator® and ADD-TOC attachments combined with CAD-CAM milled bar.

PURPOSEThe purpose of this study was to investigate changes in retention and wear pattern of Locator® and ADD-TOC attachments on a digital milled bar by performing chewing simulation and repeated insertion/removal of prostheses in fully edentulous models.MATERIALS AND METHODSLocator (Locator®; Zest Anchors Inc., Escondido, CA, USA) was selected as the control group and ADD-TOC (ADD-TOC; PNUAdd Co., Ltd., Busan, Republic of Korea) as the experimental group. A CAD-CAM milled bar was mounted on a master model and 3 threaded holes for connecting a bar attachment was formed using a tap. Locator and ADD-TOC attachments were then attached to the milled bar. Simulated mastication and repeated insertion/removal were performed over 400,000 cyclic loadings and 1,080 insertions/removals, respectively. Wear patterns on deformed attachment were investigated by field emission scanning electron microscopy.RESULTSFor the ADD-TOC attachments, chewing simulation and repeated insertion/removal resulted in a mean initial retentive force of 24.43 ± 4.89 N, which were significantly lower than that of the Locator attachment, 34.33 ± 8.25 N (P < .05). Amounts of retention loss relative to baseline for the Locator and ADD-TOC attachments were 21.74 ± 7.07 and 8.98 ± 5.76 N (P < .05).CONCLUSIONCAD-CAM milled bar with the ADD-TOC attachment had a lower initial retentive force than the Locator attachment. However, the ADD-TOC attachment might be suitable for long-term use as it showed less deformation and had a higher retentive force after simulated mastication and insertion/removal repetitions.

Patient Satisfaction and Maintenance Requirements of Classical Implant Locators versus Customized Attachments in Mandibular Implant-Retained Overdentures

Objectives: This study was performed to compare implant locators versus customized mandibular implant-retained overdentures considering patient satisfaction and prosthesis maintenance. Materials and methods: 12 completely edentulous patients from the prosthodontic department-Cairo university outpatient clinic were selected according to specific inclusion criteria. The patients were then allocated randomly into two groups using closed envelopes. For both groups, each patient received dental implants in the planned position. The patients were left for 3 months for implant healing. For group (A) the patients received two locator attachments. The attachment collar height was selected based on the soft tissue thickness keeping the retentive part 1 mm above the soft tissue level. The denture was relieved opposite the locator housing and the attachment was picked up using cold-cured resin. For group B, the implants were exposed, and healing collars were placed. After 2 weeks, the implants were scanned using an intraoral scanner. The denture was readapted using a light body closed mouth impression. The relined denture was scanned from both the fitting and the occlusal side. The scanned fitting surface was used to create an inverted virtual model and preceded till creating custom locator attachments. The generated custom attachment abutment was milled from grade V titanium blanks using a 5-axis milling machine. The abutments were anodized into gold color using an electric anodizer. The attachments were then sterilized and placed in the patient mouth as set before in the design. The pick-up of the housing was done in the same manner as group A. For both groups, the patients were given instructions for using and maintaining the overdenture. Initial denture corrections were made in the first 2 weeks if any complaint existed. The patients were recalled periodically at 3 months, 6 months, 9 months &amp; 12 months respectively. Results: Likert scale out of 5 was followed for patient denture satisfaction along 3, 6, 9, and 12 months for groups A &amp; B. Applying an Independent t-test for significance evaluation between group A and group B, precluded the higher significance of group B than group A for all follow up as P-value &lt;0.05.For prosthetic maintenance along twelve months follow-up, group B revealed a lower insignificant different incidence of prosthetic complications than group A using the Chi-square test for significance testing between proportions as P-value &gt;0.05. Conclusions: Customized locator attachments are highly recommended to retain mandibular overdentures, as they exhibited better maintenance values and more wear resistance with minimal loss of retention. Moreover, can be utilized by any presented implant system in the market, in addition, Patients were completely satisfied with their customized locators retaining their implant-supported overdentures.

Effect of Posterior Residual Ridge Resorption and Relining for Mandibular Implant Overdentures on Bending Strain Around Implants.

To examine the influence of posterior residual ridge resorption (PRRR) and relining on bending strain around implants under an overdenture. Maxillary and mandibular edentulous models were made and covered with white silicone. Four strain gauges were placed on four sides of each implant. Two tissue-level implants were placed bilaterally in the part between the lateral incisors and canines of the mandible. A maxillary conventional denture and a mandibular overdenture were fabricated to fit the models. Three levels of bone resorption around the implant were created: 0, 0.8, and 1.5 mm. The surface of the residual ridge was uniformly removed from the area near the distal side of the implant to the retromolar section, and three levels of PRRR were created (0, 1, and 1.5 mm). After the measurement, the experimental denture of the PRRR of 1 mm and 1.5 mm were relined. Locator attachments were used. A 98-N occlusal force was applied, and bending strains around the implant were measured. The Kruskal-Wallis test and Bonferroni correction were employed to analyze the data. Without relining, at each bone resorption level around the implant, the bending strain was smallest with PRRR of 0 mm and largest with PRRR of 1.5 mm. The bending strain after relining was smaller than the bending strain with ridge resorption. Bending strains after relining were smaller than bending strains with no ridge resorption, but there was no significant difference in bending strain between these three groups. As PRRR increased, the bending strain increased without relining. As bone resorption around the implant progressed, PRRR enhanced the increase in the peri-implant bending strain. Bending strain was reduced when relining was performed.

Detection of the effects of the various denture cleansing methods on overdenture retentive attachments with a scanning electron microscope

Background/Aim: The purpose of this in vitro study was to evaluate the effect of mechanical and chemical denture cleansing methods on dental attachments of varying retention with a scanning electron microscope. Material and Methods: An implant analog and a male part of a dental attachment were embedded into an acrylic block, and an abutment was screwed onto the analog. Different locator attachments with varying retention were tested using different denture cleansing methods and tap water for a time simulating 12 months of clinical use. A pull-out test was performed for each attachment, followed by analysis of the samples with a scanning electron microscope. Results: For the blue attachment group, there was no statistically significant difference between the retention values of control and chemical and mechanical denture cleansing groups (p&gt;0.05). The clear and pink attachments were affected by chemical and mechanical denture cleansing, and had significantly decreased retention values compared to the control group (p&lt;0.05). For both types of attachments, the mechanical cleansing group exhibited the lowest retention loss value. Scanning electron microscopy results showed that surface irregularities, scratch lines, and deformations were detected in chemical and mechanical denture cleansing groups for all types of retentive attachments. Conclusions: Both attachment systems with different retentions were influenced by the denture cleansing method. Considering the results, clinicians could recommend the most appropriate method to patients, one that does not adversely affect the properties of the retainer parts. Clinicians should not advise using mechanical and chemical denture cleansing methods to protect the long-term retention of pink and clear attachments.

Comparison of retention of two different attachment systems used in implant-supported overdentures

Aim:This study aims to compare the retentive capacity of two attachment systems after manual thermocycling.Settings and Design:In vitro study and Comparative trail.Materials and Methods:An edentulous mandibular Polymethyl Methacrylate model was fabricated to receive the overdentures with the two attachment systems to be compared. Two dental implants were placed in the predetermined right and left mandibular canine regions of the model. A total number of eight overdentures, four per group, were fabricated over the two implants with two attachment systems to be compared; Bar and clip attachment system (Group-1) and Locator attachment system (Group-2). All the overdentures were subjected to 5000 alternating thermal cycles using manual thermocycling. Then the samples were subjected to 100 vertical pulls each in the anterior and posterior regions using a universal testing machine and the mean retentive forces were calculated for each sample in the anterior and posterior regions, respectively.Results:The mean retentive forces after 100 vertical pulls, were calculated and tabulated for each sample in the anterior and posterior regions separately. Then, the cumulative mean of the anterior and the posterior regions were calculated for each group. The cumulative mean retentive forces of both the attachment groups were-Group-1 (Bar and clip attachment system) = 27.87 N ± 4.01 and Group-2 (locator attachment system) = 18.85 N ± 2.50 with a P value of 0.021. This difference was found to be statistically significant.Conclusion:Within the limitations of the present in vitro study, the bar and clip attachment system offered better retention than the locator attachment system.

Comparison of two resilient attachment systems for implant-/mucosa-supported overdentures with a PEKK framework: a clinical pilot study

ObjectivesThe aim of the study was to determine differences between Locator and CM LOC attachment systems regarding patient satisfaction and wear of the abutments and their inserts. Plaque accumulation onto the polyetherketoneketone (PEKK) framework and polymethylmethacrylate (PMMA) was investigated for the implant-supported overdentures.MethodsSeventeen edentulous patients were randomised to receive either Locator or CM LOC system for the first year. The total number of implants was 53. After the randomisation, 25 implants received Locator system, and 28 implants received CM LOC system in the first year. After a period of 12 months, the attachment system was exchanged from either Locator to CM LOC or vice versa. Oral Health Impact Profile (OHIP-14) questionnaires were used to evaluate patient satisfaction, chewing comfort, and pressure lesions. Prosthesis hygiene on the PMMA and PEKK surfaces was evaluated by using Stark plaque index. After the exchange of the abutments, they were stored until the end of the 24 months, and the surface wear of the abutments was analysed using a scanning electron microscope.ResultsThree patients (10 implants) died shortly before the end of the first year. Two patients (7 implants) received only Locator system since CM LOC was not indictable for their implant system. Patient’s satisfaction was increased when the attachment system was changed from Locator to CM LOC after 12 months of wearing time. Chewing ability and comfort were increased when the attachment system was changed from CM LOC to Locator after 12-month wearing time. There was no influence of the change of the attachment system on pressure lesions. The observed plaque accumulation was higher on the PMMA than on the PEKK surface. For the 8 investigated Locator abutments, the wear was within low and middle level. For the 28 investigated CM LOC abutments, the wear was within middle and high level for the terminal implants and between low and middle for the central implants (for patients who received 4 implants).ConclusionsPatient’s satisfaction and wearing comfort can be improved with implant-supported overdentures with CM LOC abutments in comparison to Locator. There was no clear difference between both attachment systems concerning the chewing ability of the patients. Plaque accumulation was observed on both attachment systems in different areas. Plaque accumulation on PEKK surface was less than on PMMA surface.Clinical relevanceThe CM LOC attachment system offers stable and comfortable wearing conditions for implant-supported overdentures. The use of PEKK as a framework material could reduce the incidence of pressure lesions.

Implant Stability Changes for a Single Implant Mandibular Overdenture.

Objectives To compare the changes in implant stability for the nonsubmerged and submerged protocols for a single-implant retained mandibular overdenture using Cendres and Metaux Locator attachment throughout a 24-month follow-up. Materials and Methods Eighty edentulous patients who were seeking to install a single implant in the midline of the completely edentulous mandible. At the day of implant installation, patients were randomized into two groups using sealed envelopes: the nonsubmerged and submerged groups. After 3 months of healing period, randomization using sealed envelopes was performed and patients were randomized to receive the Cendres and Metaux Locator attachment. The periotest readings were recorded using the Periotest M device, every 3 months for the first year and annually in the second year. The scope of this clinical trial focused only on results of the Cendres and Metaux attachment. Statistical Analysis The Mann–Whitney U -test was used for comparison between study groups for independent samples. Two-sided p -values less than 0.05 were considered statistically significant. Results There was no statistically significant difference between the mean periotest readings of both groups throughout the 24-month follow-up. Both groups showed an improvement in mean periotest readings with the submerged group tending to show greater stability at 6, 12, and 24-month follow-ups. Conclusions The nonsubmerged and the submerged healing protocols resulted in reliable periotest readings with the submerged group showing greater improvement than the nonsubmerged, although this improvement is nonsignificant when using the Cendres and Metaux attachment for a single mandibular overdenture.

Prosthodontic Rehabilitation of Patients with Double Crown and Locator Attachment - Retained Overdentures Supported by a Combination of Natural Tooth and Strategic Implants: Case Series

Abstract Prosthetic rehabilitation of edentulous patients and patients with one or two own teeth can be established by different treatment modalities. The most commonly used in the treatment of these patients is conventional complete denture or removable partial denture. However, due to increasing problems with this type of therapy, such as insufficient retention, stability, comfort and pain during mastication, it is suggested an overdenture supported by two natural teeth or implants. We will present series of clinical reports. In two clinical cases patients came to the dental office because of the impossibility of wearing lower partial denture, and in one case patient had problems with the upper partial denture. After clinical examination and radigraphic analysis, in all patients, dental implants were implanted. In first case there were implanted two dental implants in the region 41 and 43, in second case it was region 33, and in third case implanatiton is performed in the region of 14, 11, 21. Prosthetic rehabilitation was done after 3-months bone oseointegration period. The treatment consisted in the production of double crowns and overdentures that are retained with locator attachment. This design of the denture significantly improves the quality of patient’s life (the dentures are stable, chewing is improved, the feeling of thermal sensations of food and drink is present, the feeling of taste is complete, and the psychological patient becomes safer).

Effect of Locator and Telescopic Attachment on Retention value for Two-Piece and One-Piece Implant-Supported Palateless Maxillary Over Denture: An In-vitro study

Objective: This study aims to evaluate the effect of two different implant designs (one-piece dental implant and two-piece dental implant) with attachment systems on retention value in implant-supported palate less maxillary overdenture. &#x0D; Methods: Two edentulous maxillary models were fabricated from cold-cure polymethyl methacrylate resin. Four implants were inserted for each model as follows: Model I (Four one-piece implants were inserted, two implants in the canine region and two implants in the second premolar region), while Model II (Four two-piece implants were inserted, two implants in the canine region and two implants in second premolar region). The maxillary denture was constructed over each model. In model I, four ready-made titanium telescopic attachments corresponding to implant abutments were embedded in the inner surface of the overdenture. In contrast, in model II, four locator attachments corresponding to implant abutments were embedded in the inner surface of the overdenture. Initial anterior, posterior, and central retention values of overdentures were recorded and compared with the retention after 540 and 1080 cycles of insertion and removal using a digital force gauge. &#x0D; Results: Statistical analysis revealed significant differences in the initial, secondary and tertiary retention values for anterior, posterior, and central retentions for both models (higher values were recorded before insertion cycles). The higher anterior and central retention values were recorded in Model II (44.93 and 25.9) N respectively, on the other hand, the higher posterior retention value was recorded for Model I 23.3N. &#x0D; Conclusions: The type of attachment affects the retention value of maxillary overdenture. Continuous insertion and removal of the prosthesis lead to a decrease in the retention values.

Retention Loss of Locator Attachment System Different Retention Caps for Two Implant Retained Mandibular OverdentureMedhat

Purpose. The objective of this invitro study was to evaluate gradual loss of retention at different time intervals between four different colour coded retentive caps of locator R-TX attachment system through 3000 cycles resembling 3years of attachment usage. Material and Methods. According to prosthetically driven implant placement, two implants were digitally planned and placed by 3D printed surgical stent in an epoxy model. Forty-eight mandibular complete dentures divided into four groups (12 dentures for each group) were constructed to compare Loss of retention between (12 pairs of locator R-TX each retention cap: zero retention, low retention, medium retention and regular retention), each was subjected to insertion and removal cycles resembling 3years of patient usage. Retention values at zero, one, two, three years were recorded using universal testing machine. Results: Locator R-TX medium &amp;low retention showed no statistically significant retention values through three years while locator R-TX regular retention cap showed better retention values at zero, first, second year of use. Conclusion. Locator R-TX attachment systems low, medium, regular retention cap had no statistically significant different retention values at the end of third year of use while there were only statistically significant primary retention values. Clinical Implications. The importance of difference retention caps appears only in the start of over denture treatment until complete patient adaptation to over denture treatment10

Two Implant Mandibular Overdentures: Clinical and Laboratory Procedures

Edentulism is considered a poor health outcome and may compromise quality of life. Implant-supported overdentures provide a good opportunity for dentists to improve the quality of life and oral health. Atrophic mandible poses a significant challenge to successful oral rehabilitation with dental implants. The aim of this case report is to demonstrate the concept of immediate functional loading in the mandible using unsplinted implants to support a locator attachment supported overdenture.

Environmental-Community Psychology in the Disaster Research: The Importance of Social-Spatial Connections

The psychosocial literature in the context of socio-natural disasters mainly focuses on the psychological consequences of the affected people, while ignoring the psychosocial environmental factors. Here, we emphasize the relevance of community environmental psychology to analyze the subjective aspects of the relationship with the place and the community relations of the localities affected by disasters. Therefore, we propose a conceptual framework of the categories of community psychology and environmental psychology, which are related to the study of the social spatial connection in what we call socio-natural disasters. This view is illustrated by the results of a study using a hybrid approach that describes how people living in communities affected by earthquakes, tsunamis and volcanic eruptions in four locations in Chile. In a non-probabilistic convenience sample (n = 628), the responses to the scale of location attachment, location identity, residence satisfaction, community awareness and citizen participation were analyzed, as well as the narration of 17 focus groups (n = 117) on the meaning of public space construction. The conclusion is that the combination of environmental and community psychology expands the understanding of the elements of power and territorial disputes, and highlights the psychosocial defects in post disaster reconstruction solutions.

Traditional Removable Partial Dentures versus Implant-Supported Removable Partial Dentures: A Retrospective, Observational Oral Health-Related Quality-of-Life Study

Removable partial dentures (RPD) are still a valid alternative for the restoration of missing teeth. Additionally, implant-supported removable partial dentures (ISRPD) represent a valid alternative as it allows to avoid the use of clasps and increase stability. The objective of this study was to evaluate through an OHIP-14 questionnaire the level of satisfaction and quality of life (QoL) of patients treated before RPD and then with ISRPD. Twenty patients were rehabilitated with traditional RPDs, and after one year the prosthesis was modified into ISRPD, by inserting an implant and a ball or locator attachment. At the end of both phases, patients completed the Oral Health Impact Profile (OHIP-14) questionnaire. The collected data were statistically analyzed through the Wilcoxon U test, as overall OHIP score and difference between treatments. The mean of the OHIP summary (range from 0 to 56) in the RPD Group was 20.95 (±5.27). In the ISRPD Group it was 13.95 (±3.91), with a statistically significant difference (p &lt; 0.05) between the two Groups. The same findings were highlighted for the differences between groups in every domain question. Patients showed significant improvements after rehabilitation in all areas of investigation, stating how the transformation of a removable prosthesis into an implant-supported one can improve patients’ QoL with benefits in chewing ability, aesthetics and self-satisfaction.

Comparing two different angulated abutment designs on marginal bone loss around divergent two implants retaining mandibular overdentures: A radiographic prospective study.

Objectives: the aim of this study was to radiographically compare the influence of two different angulated abutment designs on marginal bone loss around 30-degree divergent two implants retaining mandibular overdentures. Materials and Methods: Thirty six patients were selected. For each patient, two distally inclined dental implants (3.5 mm × 13 mm) were bilaterally inserted in the canine regions by using stereolithography stent. Patients were divided into two groups as follows: Group AB (n=18) : Patients received two ball attachments which were screwed to the angulated overdenture abutments. Group AL (n = 18): Patients received two locator attachments which were screwed to the angled overdenture abutments. Marginal bone loss was assessed at the time of implant insertion (baseline), and after every 12 months up to 36 months by using digital periapical radiographs. Results: Both groups showed insignificant difference at the mesial aspect in peri- implant bone loss at 12 months. But, ball group recorded a significant increase in peri-implant bone loss (0.26)) in comparison to locator group (0.23). But, at the distal aspect there was a statistically insignificant difference between both groups at 12, 24 and 36 months Conclusion: The locator attachment can be considered more favorable than the ball attachments regarding the peri-implant bone loss around 15 distally inclined implants used for assisting mandibular complete over denture. Key Words: Mandibular implant overdenture, Angled abutment and peri‑implant bone loss.

Three-Dimensional evaluation of marginal bone resorption associated with flap and flapless placement of immediately loaded implants retaining mandibular overdentures with resilient stud attachments. One year randomized controlled clinical trial

Purpose: This study was carried out to evaluate Three-Dimensional marginal bone resorption with flap and flapless placement of immediately loaded implants retaining mandibular overdentures with locator attachments. Materials and methods: Ten edentulous patients (6 males and four females, with an average age of 59 years) complaining of lack of retention of mandibular dentures received two implants in the canine positions of the mandible using either flap (group 1) or flapless (group 2) surgical approach. All implants were immediately loaded with locator retained mandibular overdentures. Cone beam CT was used to measure Three-Dimensional bone loss at mesial, distal, buccal and lingual surface of each implant. Measurements were made at baseline, six and 12 months later after delivery. Results: The survival rate was 90% and 100% for flap and flapless groups respectively. For all implant surfaces, flap group showed significant higher bone resorption than flapless group. After 12 months, the highest bone loss occurred at the mesial surface and the lowest bone loss occurred at the buccal surface in the flap group. For flapless group, the highest bone loss occurred at buccal surface and the lowest bone loss located at lingual surface. For all implant surfaces in both groups, marginal bone loss after 12 months was significantly higher than the values after six months. Conclusion: Within the limitations of this study, the flapless surgical approach is recommended for locator retained mandibular overdentures than the flap approach as it was associated with reduced marginal bone loss after 12 months.

Impact of Locator Attachments with Different Retentive Insert Materials on Bite Force in Mandibular Implant Overdenture

Impact of Locator Attachments with Different Retentive Insert Materials on Bite Force in Mandibular Implant Overdenture

Design and Experimental Implementation of a Passive Dynamic Vibration Absorber to Attenuate Broadband Vibration

The challenge of designing an effective vibration absorber for any mechanical or mechatronic system is formidable. A good vibration absorber must provide broadband vibration reduction yet still keep in lightweight and size to minimize space requirements and maximize equipment accessibility. Broadband vibration is usually attenuated by using an active or semi-active vibration absorber. However, these methods are relatively costly and complicated compared with a passive vibration absorber. Moreover, passive vibration absorber often limited to narrowband frequency reduction since, in the past, it is usually tuned to the targeted frequency or optimum damping and optimum tuning ratio. This paper demonstrated that a passive vibration absorber could be implemented to reduce the broadband vibration of a system, considering the effect of the parameter of passive vibration absorber, the location attachment of the absorber, and the targeted mode shape. The result shows that a properly tuned passive vibration absorber can reduce the root mean square amplitude vibration by 60.91%, covering the first four vibration modes (0 to 300Hz).

Effect of Locator Attachments with Different Retentive Insert Materials on Peri-implant Tissue Health in Mandibular Implant Overdenture

Effect of Locator Attachments with Different Retentive Insert Materials on Peri-implant Tissue Health in Mandibular Implant Overdenture