Hakan Bilhan

The role of Candida albicans hyphae and Lactobacillus in denture-related stomatitis

Denture-related stomatitis (DRS) is still a dilemma in removable prosthodontics. The aim of this study was to investigate the relationship of DRS with the presence of Candida albicans hyphae and Lactobacillus. A total of 91 patients wearing maxillary and mandibular complete dentures were included in the present study and tested mycologically as well as bacteriologically. A statistically significant association of DRS was found with denture age (pu2009=u20090.003) and continuous denture wearing (pu2009=u20090.015). Presence of C. albicans hyphae was shown to be significantly higher in DRS cases (pu2009<u20090.01), and there was a statistically significant positive correlation between presence of hyphae and C. albicans (pu2009<u20090.01). Another interesting finding was that DRS patients showed higher Lactobacillus counts in their saliva (pu2009=u20090.04), as well as in the palate (pu2009=u20090.028). C. albicans is an important factor in the development of DRS. Hyphae seem to facilitate the rise of C. albicans counts and be related to the inflammatory response of the tissues. Lactobacillus seems to play an important role in the presence of DRS, as well. In agreement with many other studies, the results of this study confirm the importance of denture age and continuous denture wearing in the development of DRS.

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.

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.

The effect of attachment type and implant number on satisfaction and quality of life of mandibular implant-retained overdenture wearers.

OBJECTIVEnThe aim of this study was to compare the quality of life and patient satisfaction outcomes of two attachment systems in mandibular overdentures with different numbers of supporting implants.nnnMATERIALS AND METHODSnSixty-two edentulous patients with either splinted or single attachments in mandibular implant overdentures with different numbers of supporting interforaminal implants were investigated for patient satisfaction and quality of life in this retrospective study. Comparisons between groups were perceived by the Mann-Whitney U test. Relations among the parameters were investigated by Spearmans rho correlation analysis. The results were evaluated statistically at a significance level of p < 0.05.nnnRESULTSnNo statistically significant association is found between visual analogue scales scores and attachment type as well as implant number (p > 0.05), whereas Oral Health Impact Profile (OHIP)-14 total scores for patients with 4-implant-supported bars were significantly lower than all the other attachment types (p < 0.05). Additionally, a negative (rate = 32.2%), statistically significant association between period of edentulism and total OHIP-14 scores was detected (p < 0.05).nnnCONCLUSIONSnA mandibular implant-retained overdenture supported with four implants and bar attachments shows the highest quality of life score and patient satisfaction is not influenced by the number of implants or attachment type.

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

BACKGROUNDnThere 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.nnnPURPOSEnAssessment 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.nnnMATERIALS AND METHODSnSixty-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.nnnRESULTSnThe 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%).nnnCONCLUSIONSnMBL 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.

A quality-of-life comparison between self-aligning and ball attachment systems for 2-implant-retained mandibular overdentures.

The aim of this study was to evaluate the self-aligning overdenture attachment system by comparing its oral health-related quality of life (OHRQL) with a traditionally used ball attachment system. In this randomized, within-subject crossover trial, 25 edentulous subjects each received 2 mandibular implants, and were then assigned to receive either self-aligning or traditional ball attachments. After 3xa0months, all subjects were switched to the second attachment type. The OHRQL was evaluated for both of the treatments using the short form of the Oral Health Impact Profile (OHIP-14). A subanalysis among subjects with below-average space available for attachment placement was also performed. Wilcoxon signed-rank test was used to compare differences between groups. Scores on the OHIP-14 physical disability domain were significantly better for the self-aligning attachment system (P u200a=u200a .049). Among subjects with below-average attachment space, functional limitation, psychological discomfort, physical disability, psychological disability, and total OHIP-14, scores were significantly better for the self-aligning attachment system (P u200a=u200a .041, P u200a=u200a .047, P u200a=u200a .048, P u200a=u200a .026, and P u200a=u200a .005, respectively). The self-aligning attachment system for 2-implant-retained mandibular overdentures is equal or superior to traditional ball attachments in all domains of the OHIP-14.

The comparison of marginal bone loss around mandibular overdenture-supporting implants with two different attachment types in a loading period of 36 months

OBJECTIVEnThe aim of this study was to assess the influence of attachment types on the marginal bone loss (MBL) around dental implants supporting mandibular overdentures (OVD).nnnBACKGROUNDnThere are a number of in vitro studies evaluating the influence of several factors on MBL around implants.nnnMATERIAL AND METHODSnMandibular OVD patients appearing at routine recall sessions consecutively 6, 12, 24 and 36 months after loading were included in the study group. All patients received mandibular OVD with either ball or bar attachments. Measurements were obtained from images of successive radiographs, which were scanned and digitised before, and analysed at ×20 magnification. Statistical analyses were utilised in this study to assess the mean marginal bone level changes as well as to explore the potential effect of several parameters such as the cantilever or the attachment type on bone loss.nnnRESULTSnOne hundred and twenty-six implants in 51 patients with a mean age of 59.39 ± 9.99 years were evaluated. There was no statistical significant difference between the distal and mesial bone loss rates of single or splinted attachment types, whereas bone loss rates were statistically higher in cantilever situations.nnnCONCLUSIONnWithin the limitations of this study, gender, age and diameter of the implants do not play a role in MBL. Length of the implant is an important factor in marginal bone level maintenance. The attachment type for OVD support seems not to influence MBL, but cantilevering of the bars increases bone loss significantly.

The Effect of Mucine, IgA, Urea, and Lysozyme on the Corrosion Behavior of Various Non-precious Dental Alloys and Pure Titanium in Artificial Saliva

The corrosion of dental alloys has biological, functional, and aesthetic consequences. Various studies have shown that protein solutions can inhibit the corrosion of alloys. This study is planned to determine the relationship of organic constituents of saliva and the corrosion of dental alloys. The organic constituents are IgA, mucine, urea, and lysozyme which are encountered in the highest amounts in saliva and the dental materials are titanium (Ti), Co—Cr—Mo and Ni—Cr—Mo alloys, and dental amalgam, the most often used metallic components in dentistry. In particular, the interactions between the commonest salivary proteins, IgA, mucine, urea and lysozyme, and Ti, Co—Cr—Mo, Ni—Cr—Mo and dental amalgam were investigated. Each alloy was evaluated by cyclic polarization in each medium. The general anodic and cathodic behavior during forward and reverse cycles, the corrosion and passivation current densities (μA/cm2 ), and the corrosion and the pitting potentials (mV) were determined. The results have shown that Ni—Cr—Mo and dental amalgam alloys are highly susceptible to corrosion in all the investigated media. The Co—Cr—Mo alloy has shown high passive current densities in the solution of mucine and lysozyme in artificial saliva. Titanium instead, has shown a high resistance to corrosion and a stable passive behavior in all media, especially in a solution of mucine and IgA in synthetic saliva. Mucine and IgA, as well as urea and lysozyme, appeared to enhance the formation of a passive film layer on the Ti metal surface, thus inhibiting the corrosion. Based on the study findings, and especially considering the problem of nickel allergy and toxicity of mercury released from dental amalgam, the use of Co—Cr—Mo alloys and Ti to Ni—Cr—Mo alloys is recommended and alternatives to dental amalgam should be sought for patients with impaired salivary flow.

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

BACKGROUND AND OBJECTIVEnIt 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.nnnMATERIAL AND METHODSnThirty-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.nnnRESULTSnNo 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.nnnCONCLUSIONnThe 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.