Onur Geckili

Influence of surgical technique, implant shape and diameter on the primary stability in cancellous bone

Achievement of primary stability during surgical placement of dental implants is one of the most important factors for successful osseointegration depending on various anatomical, surgical and implant-related factors. Resonance frequency analysis (RFA) has been shown as a non-invasive and objective technique for measuring the stability of implants. The aim of this study was to evaluate the effect of some surgical and implant-related factors in enhancing primary stability and to estimate a correlation between RFA and insertion torque (IT) in proximal regions of cow ribs representing cancellous bone. Fifteen implant beds were prepared in the most proximal region of six fresh cow ribs. Ninety implants with three different shapes and two different diameters were placed with two different surgical techniques, and the primary stability was compared using RFA and IT. Significantly higher RFA and IT values were achieved when under-dimensioned drilling was used as the surgical method (P<0·01); significantly higher IT values were obtained with the use of wider implants (P<0·01) and partially conical Astra Tech implants showed the highest IT values (P<0·01). When all the implants were considered, significant correlations between the IT and RFA values were noted (%40·6, P<0·05). Partially conical implants with a wide diameter to be placed with the modified surgical technique proposed appear to be useful in enhancing the primary stability in cancellous bone.

Evaluation of possible prognostic factors for the success, survival, and failure of dental implants.

Purpose:To analyze the prognostic factors that are associated with the success, survival, and failure rates of dental implants. Material and Methods:Data including implant sizes, insertion time, implant location, and prosthetic treatment of 1656 implants have been collected, and the association of these factors with success, survival, and failure of implants was analyzed. Results:The success rate was lower for short and maxillary implants. The failure rate of maxillary implants exceeded that of mandibular implants, and the failure rate of implants that were placed in the maxillary anterior region was significantly higher than other regions. The failure rates of implants that were placed 5 years ago or more were higher than those that were placed later. Conclusions:Anterior maxilla is more critical for implant loss than other sites. Implants in the anterior mandible show better success compared with other locations, and longer implants show better success rates. The learning curve of the clinician influences survival and success rates of dental implants.

Complication rates and patient satisfaction with removable dentures

PURPOSE The purpose of this clinical study was to evaluate the frequency and type of prosthetic complications in relation to type and properties of removable dentures and to investigate the influence of these complications and several data about the existing dentures on patient satisfaction. MATERIALS AND METHODS Ninety nine patients (44 males and 55 females) wearing removable dentures have been included in the study. The complications of the patients were recorded; patient satisfaction was determined with a Visual Analog Scale (VAS) and the relationship of complications and patient satisfaction with several data about the dentures such as denture age, type of denture, centric relation and vertical dimension was investigated. Kruskal Wallis, Mann Whitney U and Chi square tests were used for statistical analyses. The results were evaluated statistically at a significance level of P<.05. RESULTS Need for addition of artificial teeth for dentures with correct centric relations was found to be significantly lower than dentures with wrong centric relations (P<.01). Loss of retention, ulcerations and high vertical dimension affected the VAS chewing ability scores negatively and ulcerations affected the VAS phonation scores negatively (P<.05). CONCLUSION Considering the results of this study, it can be concluded that loss of retention, ulcerations and high vertical dimension caused patient dissatisfaction. Additionally, dentures with wrong centric relations caused need for addition of artificial teeth.

Maintenance requirements associated with mandibular implant overdentures: clinical results after first year of service.

The aim of this clinical study was to evaluate the prosthodontic maintenance requirements during the first year of service of mandibular overdentures supported by interforaminal implants and to assess the influence of attachment type, implant number, and bite force on these requirements. Fifty-nine patients treated with mandibular implant overdentures between the years 2004 and 2009 and appearing in the 12th-month recall were included in this study. The overdentures constituted 4 groups: 2 single interforaminal implants (1 group with locator and 1 group with ball attachments), 3 single interforaminal implants, 3 splinted interforaminal implants (bar), and 4 splinted interforaminal implants (bar). During the examination, prosthetic parameters such as occlusion, tissue adaptation, condition of the retentive mechanism (matrice and patrice), and the condition of the denture-bearing tissues were evaluated and recorded. No statistically significant relation was found between attachment type, bite force values, implant number, and the occurring complications except the need for relining, which was found significantly more in the ball attachments than in other attachment groups (P  =  .03). After 12 months following the overdenture insertion, there seems to be no relation between occurring complications and patient-related factors, such as maximum bite force, age, and gender, as well as factors related to the overdentures such as number and type of attachments.

Impact of mandibular two-implant retained overdentures on life quality in a group of elderly Turkish edentulous patients

The aim of the study was to examine the influence of mandibular two-implant retained overdentures on life quality of elderly Turkish patients. The study population comprised 78 edentulous complete denture wearers (aged 65-82) seeking implant-retained mandibular overdentures at Istanbul University, Turkey. Every patient received 2 dental implants in the interforaminal region of the mandible and maxillary conventional dentures and mandibular implant retained overdentures 6 weeks after surgery. Turkish versions of oral health impact profile (OHIP-14) and the United Kingdom oral health-related quality of life (OHQoL-UK) were used for the evaluation of life quality before and after treatment. Compared to pretreatment scores, subjects had statistically significant improvements in life quality after receiving new dentures (p < 0.05). Based on these results, it can be concluded that mandibular two-implant retained overdentures improve the life quality of elderly edentulous Turkish patients.

The Effect of Maximum Bite Force, Implant Number, and Attachment Type on Marginal Bone Loss around Implants Supporting Mandibular Overdentures: A Retrospective Study

BACKGROUND There remains controversy regarding the clinical reasons for late-implant bone loss, which is a critical factor in the long-term success of implant-supported overdentures. PURPOSE Assessment of the effect of such factors as attachment type, number of implants, gender, age, and maximum bite force (MBF) on marginal bone loss (MBL) around implants supporting mandibular overdentures. MATERIALS AND METHODS Sixty-two edentulous patients rehabilitated with two-, three-, or four-implant-supported mandibular overdentures at a university clinic between January 2006 and January 2007 and having a digital panoramic radiograph at the time of loading, were included in this study. All patients received digital panoramic radiographs, and MBL was measured by subtracting bone levels from the first radiograph. MBF was measured using a bite force transducer. RESULTS The amount of bone loss 48 months after loading was found to be unrelated to gender, age, implant number, attachment type, and splinting (p = .741, p = .953, p = .640, p = .763, p = .370, respectively). A significant correlation was observed between the MBF and the MBL of distal implants on the right side (p < .01, 79.9%) and the MBF and the MBL of distal implants on the left side (p = .011, 34.6%). CONCLUSIONS MBL around implants supporting mandibular overdentures seems not to be affected by number of implants, attachment type, age, or gender; however, MBL is affected by MBF.

The evaluation of the success of immediately placed single implants: a retrospective clinical study.

Purpose:The aim of this retrospective clinical trial was to evaluate the survival rates and the marginal bone levels of immediately placed implants in fresh extraction sockets in a period of 36 months. Patients and Methods:One hundred seventeen patients who had received 165 immediately placed implants and followed up for 36 months after loading were included in this retrospective study. Survival rate and mesial and distal marginal bone levels of all implants were determined with the measurements made on periapical radiographs at baseline and recall evaluations. Results:The results of clinical evaluation showed a survival rate of 93.94%. Ten of 165 implants failed: 7 implants in female patients indicating 90.28% survival rate and 3 male patients with 93.4% survival rate. The mean age of patients with implant failure was 60.8 years. No statistically significant differences in marginal bone levels with respect to localization, age, gender, grafting, and implant brands were noted. Grafting did not influence plaque index, gingival index, and periimplant probing depth in a statistically significant way. Conclusions:The results suggest that immediately placed single implants show acceptable survival rates and mesial and distal marginal bone levels in 36-month follow-up period.

A comparative in vitro evaluation of two different magnetic devices detecting the stability of osseo-integrated implants.

BACKGROUND AND OBJECTIVE It is unknown whether the resonance frequency analysis (RFA) measurements made by two different magnetic resonance frequency analysers are comparable. This in vitro study was designed to compare the RFA measurements made by the two magnetic resonance frequency analysers and to evaluate the intra- and interobserver reliability of the magnetic devices. MATERIAL AND METHODS Thirty-two implants were placed in four cow ribs. The RFA value of each implant was measured by five different examiners. The measurements were repeated five times, in both the buccal and mesial directions, for each implant at 2 h intervals, and the averages of registered implant stability quotient (ISQ) units were recorded as the buccal ISQ value and the mesial ISQ value for every implant. RESULTS No statistically significant differences (p>0.05) were observed between the RFA measurements made by the two magnetic devices. The intra-observer reliability of both devices was excellent, whereas the interobserver reliability of the devices was poor. CONCLUSION The results of the RFA measurements of both tested devices overlap. Although both devices show excellent intra-observer reliability, there are variations between the measurements of different examiners.

The influence of maximum bite force on patient satisfaction and quality of life of patients wearing mandibular implant overdentures.

The treatment of edentulism with traditional complete dentures can often induce impaired masticatory function due to limited retention and stability, especially in the lower jaw. Mandibular interforaminal implants have been widely used to stabilize the dentures, consequently improving masticatory performance in edentulous individuals. The aim of the present study was to document the influence of this improved masticatory function on patient satisfaction and quality of life of patients wearing mandibular implant-supported overdentures. Sixty-two patients treated with various types of implant-supported mandibular overdentures between 2004 and 2007 were included in this retrospective study. Maximum bite force (MBF) was measured bilaterally using a device with 2 strain gauges connected to a strain gauge measurement system. All the included patients were asked to fill out visual analog scale (VAS) forms based on general and chewing satisfaction and OHIP-14 forms. Results were analyzed by the Spearman rho test. No statistically significant correlation was found between MBF values and VAS general or VAS chewing satisfaction or Oral Health Impact Profile scores (P > .05). The results indicate that MBF is not associated with the satisfaction or quality of life of implant-supported mandibular overdenture wearers.

The influence of implant number and attachment type on maximum bite force of mandibular overdentures: a retrospective study

AIM Assessment of the influence of such factors as attachment type, number of implants, gender and age of patients on maximum bite force (MBF). MATERIAL AND METHODS Sixty-two edentulous patients (32 females, 30 males; aged 64.03 ± 10.07 years, range 42-90 years) with mandibular implant overdentures with various attachment types were included in the study and their MBFs were recorded. The results were evaluated statistically at a significance level of p < 0.05. RESULTS The MBF in male patients was found to be statistically significantly (p < 0.05) higher than in female patients. No statistically significant differences (p > 0.05) were found with respect to age groups, attachment types and number of implants supporting the mandibular overdentures. CONCLUSION Within the limitations of this study, it is concluded that independent of the number applied, dental implants increase MBF in edentulous patients. While males show higher bite force, patient age and attachment type seem not to play an important role.