Comparison of Three Different Types of Two-Implant-Supported Magnetic Attachments on the Stress Distribution in Edentulous Mandible.

Two-implant-retained mandibular overdentures with magnetic attachments can provide an effective treatment modality for edentulous patients. In this study, a three-dimensional finite element analysis was used to compare the biomechanical characteristics of three different types of magnetic attachments in two-implant-retained mandibular overdentures. Flat-type, dome-type, and cushion-type of the magnetic attachments were designed to retain the overdenture. Four types of load were applied to the overdenture in each model: 100 N vertical and oblique loads on the right first molar and a 100 N vertical load on the right canine and the lower incisors. The biomechanical behaviors of peri-implant bone, abutment, and mucosa were recorded. In vertical incisors, vertical right canine, and oblique molar loading condition, the flat-type group exhibited the highest levels of maximum equivalent strain/stress in the peri-implant bone. The total deformation of mucosa and the maximum equivalent strain/stress in the oblique molar loading condition are about two times as the vertical molar loading condition. These results suggested that both cushion-type and dome-type of the magnetic attachments are better choices in two-implant-retained mandibular overdentures, and oblique loading is more harmful than vertical loading.

An International Survey among Prosthodontists of the Use of Mandibular Implant-Supported Dental Prostheses.

PURPOSE: To evaluate the use of implant-supported overdentures (IOD) and implant-supported fixed dental prostheses (IFDP) in patients with edentulous mandibles among international prosthodontists. MATERIALS AND METHODS: A questionnaire was sent by e-mail to all clinically active prosthodontists in the International College of Prosthodontists with questions related to implant treatment of the edentulous mandible performed in 2015. RESULTS: One hundred and sixteen prosthodontists from 33 countries responded to the questionnaire. The vast majority of the responding prosthodontists was faculty or worked in private practice, and the great majority had performed treatment with mandibular implant-supported dental prostheses; however, two thirds of the respondents reported that <20% of the implant patients in their clinic had received treatment related to edentulous mandibles. The majority reported using 2 implants (84%), while 13% used 4 for overdenture retention. There were great variations regarding retention systems used for mandibular IODs; the most common was individual Locator attachments. Cost was considered the most common reason to choose mandibular IOD, There was a wide variation of materials used for mandibular IFDPs. The most common combination included milled titanium frameworks and acrylic resin teeth. CONCLUSIONS: This survey, completed by 116 prosthodontists from 33 countries, showed that implant treatment for edentulous mandibles is common, but there was great variation among the respondents regarding amount of treatments performed, design, and materials used for the implant prostheses.

Longitudinal Assessment of Denture Maintenance Needs in an Overdenture Population.

PURPOSE: To evaluate the longitudinal denture maintenance needs of a tooth-supported overdenture population. MATERIALS AND METHODS: This prospective cohort study was composed of patients who had received tooth-supported overdentures from 1974 to 1994 in the Department of Prosthodontics, University of Iowa. There were 272 persons with 662 abutments who fulfilled the inclusion criteria. To simplify analysis and reduce the number of confounding variables, only those participants wearing complete maxillary dentures and opposing complete mandibular overdentures supported by teeth #22 and #27 were included in this analysis. The denture maintenance needs of these participants were identified and related to age, gender, length of time wearing overdentures, number of medications, and denture-wearing habits. Descriptive statistics and bivariate analyses were used for the statistical analysis (α = 0.05). RESULTS: Of the 91 participants (mean age = 59.5 ± 10.1 years; 63.7% male) who fulfilled the inclusion criteria at baseline, 48.4% took 1 to 3 medications daily, and 84.6% wore their dentures day and night. The percentages of participants who needed one or more of the following denture treatments were: 91.2% denture base adjustments, 76.9% laboratory processed relines, 61.5% denture remakes, 33% laboratory remount and occlusal adjustment, 22% repaired bases, and 19.8% needed denture teeth replaced. Bivariate analyses indicated that participants who were 65 years and older needed more denture adjustments than patients younger than 65 years (p = 0.0343). Participants who had worn overdentures for more than 5 years were more likely to require denture remakes (p = 0.0304). Participants who wore their dentures only during the day were less likely to require repairs (p = 0.0403). Participants who did not take any medications were significantly less likely to require denture base repairs (p = 0.0258). For the 35 participants who returned for recalls at all 4 time points, males were more likely to need denture teeth repaired or replaced (p = 0.0335) and those aged 50 to 64 were more likely to need 2 or more adjustments (p = 0.0311). No overdenture abutments were lost by the participants in this study. CONCLUSIONS: According to the results of this study, age, medication usage, denture-wearing habits, and age of the overdentures were significant factors associated with denture maintenance needs. Persons wearing overdentures need regular recalls, because they have continuing maintenance needs.

O papel do índex de gesso na precisão da transferência de implantes para confecção de sobredentadura mandibular / The role of the stone index in the precise implant impression of mandibular overdentures

Este artigo descreve a técnica de utilização de um índex de gesso para diminuir os problemas de adaptação da barra metálica em sobredentaduras mandibulares. São detalhados também a técnica de moldagem e a concomitante transferência dos implantes. (AU).

This article describes the utilization of a plaster index to avoid the problems of adaptation of the metal bar in mandibular overdentures. The impression technique and the simultaneous transference of the implants are also detailed. (AU).

Does a mandibular overdenture improve nutrient intake and markers of nutritional status better than conventional complete denture? A systematic review and meta-analysis.

OBJECTIVES: The need for denture treatment in public health will increase as the population ages. However, the impact of dentures on nutrition, particularly overdenture treatment, remains unclear although the physical and psychological effects are known. We investigated whether treatment with a mandibular implant supported overdenture improves nutrient intake and markers of nutritional status better than a conventional complete denture in edentulous patients. DESIGN: Systematic review and meta-analysis. METHODS: Medline, EMBASE and the Cochrane Central Register of Controlled Trials were searched for eligible studies published up to April 2016. We included studies which compared the treatment effect of an overdenture to conventional denture on nutrition, in which primary outcomes included changes in intake of macronutrients and/or micronutrients and/or indicators of nutritional status. Two reviewers independently evaluated eligible studies and assessed the risk of bias. We used a fixed effects model to estimate the weighted mean difference (WMD) and 95% CI for change in body mass index (BMI), albumin and serum vitamin B12 between overdenture and conventional denture 6 months after treatment. RESULTS: Of 108 eligible studies, 8 studies involving 901 participants were included in the narrative appraisal. Four studies reported changes in markers of nutritional status and nutrient intake after treatment with a prosthetic, regardless of type. In a meta-analysis of 322 participants aged 65 years or older from three studies, pooled analysis suggested no significant difference in change in BMI between an overdenture and conventional denture 6 months after treatment (WMD=-0.18 kg/m(2) (95% CI -0.52 to 0.16)), and no significant difference in change in albumin or vitamin B12 between the two treatments. CONCLUSIONS: The modifying effect of overdenture treatment on nutritional status might be limited. Further studies are needed to evaluate the effectiveness and efficacy of denture treatments.

Cierre de diastema con resinas compuestas híbridas / Diastema closure with hybrid composite resins

El tratamiento para el cierre de diastemas fundamentalmente está enfocado a otorgar estética y salud periodontal. Los diastemas pueden ser resueltos con prótesis y ortodoncia, sin embargo, estas opciones generalmente requieren de preparaciones del tejido sano, incluyen procedimientos de laboratorio y aumentan el tiempo clínico. La utilización de resinas compuestas constituye una opción estética y funcional para estos casos en los que se requiere de mínima intervención sobre el tejido sano o de ninguna. El propósito de esta presentación es describir un caso de cierre de diastema central anterosuperior utilizando resinas compuestas híbridas. Una paciente femenina de 21 años de edad acude a consulta para tratarse un diastema central superior. Se le propuso realizarle un cierre con resina compuesta híbrida. Se aplicó consentimiento informado y se obtuvo aprobación. Se realizó resolución del diastema con técnica incremental con resina híbrida hasta lograr el punto de contacto cuidando la salud periodontal. Se planificó el tratamiento, se pulieron las superficies a incrementar, se aplicaron sistemas adhesivos y se aplicaron capas de resina hasta lograr el resultado deseado. Mejoró la estética y se logró la total satisfacción de la paciente. En este caso, los pasos de la técnica de restauración directa con incremento d4e resina compuesta híbrida fueron seguidos adecuadamente. Se logró el cierre del diastema y el restablecimiento del punto de contacto sin forzar la papila interdental(AU)

Treatment for diastema closure is mainly aimed at providing periodontal health and an appropriate esthetic appearance. Diastemata may be treated with prosthesis and orthodontics, but these options generally require preparation of the healthy tissue, including laboratory procedures which increase clinical time. The use of composite resins is an esthetic, functional option for cases in which little or no intervention is required upon healthy tissue. The paper is aimed at describing a case of central anterior superior diastema closure using hybrid composite resins. A 21-year-old female patient presents at consultation requesting treatment for a central superior diastema. Closure with hybrid composite resin was suggested. After obtaining informed consent, resolution of the diastema was performed using an incremental technique with hybrid resin until the contact point was reached, taking care of periodontal health. Treatment was planned, the surfaces to be increased were polished, adhesive systems were applied and resin layers were placed until the desired result was achieved. Esthetic appearance was improved, with total patient satisfaction. In this case the steps of direct restoration technique with hybrid composite resin increase were adequately followed. Diastema closure and contact point restoration were achieved without forcing the interdental papilla(AU)

Oral aesthetic-related quality of life of muco-supported prosthesis and implant-retained overdenture wearers assessed by a new, short, specific scale (QoLDAS-9).

OBJECTIVES: To validate a new questionnaire for evaluating the 'Oral aesthetic-related quality of life (OARQoL)' of prosthetically restored patients. 'OARQoL' assesses the impact of the self-perceived dental aesthetics on patients' well-being. METHODS: The 'Quality of Life associated with Dental Aesthetic Satisfaction (QoLDAS)' index was designed. After a pilot trial, 70 patients were distributed into two groups depending on their type of prosthetic rehabilitation: Group 1 (CD; n=34): muco-supported complete dentures, and Group 2 (IO; n=36): implant-retained overdentures. Patients answered the QoLDAS and the Oral Health Impact Profile (OHIP-20sp) questionnaires, and reported their satisfaction on a visual analogue scale (VAS). Socio-demographic and prosthesis-related factors were registered. Psychometric properties of the QoLDAS were investigated. Correlations between both indices were explored using the Spearman's rank test. Descriptive and non-parametric probes were run to evaluate the effect of the study variables on the OARQoL (α=0.05). RESULTS: The QoLDAS-9 was reliable and valid. The factor analysis confirmed the existence of three dimensions and meaningful inter-correlations among the nine finally included items. Both scales were inversely correlated. The self-reported aesthetic and functional satisfaction and the education level significantly modulated the OARQoL as measured with the QoLDAS-9. CONCLUSIONS: The QoLDAS-9 confirmed its psychometric capacity for assessing the OARQoL of CD and IO wearers. Both groups showed comparably high OARQoL. Superior education degrees lead to lower OARQoL. CLINICAL SIGNIFICANCE: The QoLDAS-9 may be recommended for anticipating the effect of prosthetic restorations on OARQoL. CD and IO are predictable treatment options for improving the aesthetic self-perception of edentulous patients.

Three-Year Analysis of Fixed and Removable Telescopic Attachment-Retained Implant-Supported Dental Prostheses: Survival and Need for Maintenance.

PURPOSE: The purpose of this retrospective clinical study was to evaluate the clinical outcomes of fixed implant-supported dental prostheses (FISDPs) and removable ISDPs (RISDPs) retained by telescopic attachments, the factors influencing survival, and the type and number of maintenance treatments required during the observation period. MATERIALS AND METHODS: This retrospective clinical study is based on patients who were provided with ISDPs between 2004 and 2010. Patient sex, type of prosthesis, location, opposing dentition, and the effect of continuous follow-up on the probability of a favorable outcome, as well as the number of maintenance treatments, were analyzed. A statistical analysis was performed using the Kaplan-Meier method. RESULTS: A sample of 233 patients with 157 FISDPs and 76 RISDPs supported by a total of 567 implants was randomized and included in the analysis. The mean observation period was 15.9 ± 15.4 months (maximum, 66.0 months). During the observation period, 3.9% of prostheses (7/157 FISDPs and 2/76 RISDPs) ceased to function and 2.3% of implants (13 implants) were lost. The mean survival time was 59.7 ± 2.3 months, with a survival probability of 90.2% after 3 years. Prostheses in the mandible showed significantly higher survival rates than those in the maxilla. Maintenance treatments had to be performed at an earlier stage for patients with RISDPs than for patients with FISDPs. In patients with a conventional removable prosthesis in the opposing arch, the time until maintenance was needed was significantly shorter. CONCLUSION: Within the limitations of a retrospective study, it can be concluded that the FISDPs and RISDPs show equally good survival rates after 3 years in function. RISDPs showed a greater and earlier need for maintenance treatments during the first years in function.

Survival of teeth treated with cast post and cores: A retrospective analysis over an observation period of up to 19.5 years.

STATEMENT OF PROBLEM: Scientific data about the long-term survival of teeth treated with cast post and cores are scarce. Retrospective studies often use different target events for their analyses. A comparison is therefore complicated. For associated tooth-, jaw-, and patient-related factors little evidence exists as to their effect on survival. PURPOSE: The purpose of this study was to extend the knowledge on the survival of teeth treated with cast post and cores for observation periods of more than 10 years. A decrease or increase in survival times according to the presence or absence of associated parameters needs to be evaluated. MATERIAL AND METHODS: A retrospective evaluation was conducted of all cast post and cores inserted in 1 university clinic between January 1992 and June 2011. A Kaplan-Meier survival analysis was carried out by using extraction as the target event. The survival curves for different tooth types, the presence or absence of adjacent teeth, and the prosthetic restoration of the respective jaws were compared by using the log-rank test (α=.05). A Cox regression model was calculated for multivariate analyses. RESULTS: A total of 717 cast post and cores for 343 patients were recorded. The mean survival time was 13.5 years. A statistically significant decrease in survival times was found for canines (11.9 years) and premolars (13.4 years) versus molars (14.1 years), no adjacent teeth (10.6 years) versus at least 1 adjacent tooth (13.8 years), and the restoration with removable dental prostheses (12.5 years) versus fixed dental prostheses and single crowns (13.9 years). The largest reduction in survival time was found for teeth being used as an abutment for a double crown-retained removable partial dental prosthesis (telescopic denture) (9.8 years). Tooth type and adjacent tooth status remained as significant variables within the multivariate Cox regression model. CONCLUSIONS: Cast post and cores have an acceptable long-term survival time. Because different factors may influence survival, considering these factors in treatment planning may increase the long-term success of these restorations.

Incidence of attachment loss of canines in an overdenture population.

STATEMENT OF PROBLEM: Caries and periodontal disease are the most common cause of tooth loss in overdenture populations. Longitudinal data on attachment loss in this population have not been well reported. PURPOSE: The purpose of this longitudinal study was to measure periodontal attachment loss in overdenture abutments. MATERIAL AND METHODS: In this longitudinal overdenture study, 272 persons fulfilled all of the inclusion criteria. These persons had 662 teeth, 465 (70.2%) of which were canines. This report focused only on participants with canines who returned for 3 consecutive recalls in the 42 months of the study and included 53 persons with 116 canines. During this 42-month period, 6 teeth were extracted. Attachment loss was measured at baseline and at 6 to 18 months, 19 to 30 months, and 31 to 42 months at the mesial, distal, mid-buccal, and mid-lingual surface of each tooth, and was calculated as the combination of pocket probing depth plus height above the gingiva. Attachment loss was compared at each recall. A single examiner made all the measurements. RESULTS: At baseline, the greatest amount of loss was at the mid-buccal surface (5.43 mm), followed by the mid-lingual (4.95 mm), distal (4.41 mm), and mesial (4.35 mm) surfaces. This pattern of attachment loss did not change over the 3 time periods, except that, at the 6 to 18-month recall, the distal measurement was less than at baseline. This decrease could be due to the wear of the abutment or loss of a restoration due to caries. Attachment loss was greater on the mandibular abutments than on the maxillary abutments and could be due to the greater amount of movement of the mandibular overdenture, especially in a buccolingual direction. CONCLUSION: Attachment loss varied by arch and by site in patients who wore overdentures.

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

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

Partial Edentulism based on Kennedy's classifcation: an epidemiological study.

BACKGROUND: The aim of this study was to determine the incidence of different Kennedy's classes of partial edentulism during 18 months period. MATERIALS AND METHODS: Patients were clinically examined for various Kennedy's classes of partial edentulism in the outpatient department (OPD), prosthodontics, GPRDCH, Kurnool (Andhra Pradesh). RESULTS: Of the total 1,420 OPD patients, Kennedy's class III was the most frequent classification encountered (62%) and followed by Kennedy's class I (18%), class II (11%), and class IV (9%) in decreasing order. CONCLUSION: The patients with various Kennedy's classes of partial edentulism can be offered various treatment modalities like removable cast partial dentures, fixed partial dentures, over dentures and implant supported dentures. This study can be crucial for screening the population for incidence of tooth loss as a factor of gender and age. Clinical significance: Tooth loss appears to have an important role in the loss of esthetics and mastication. Study of incidence of various classes of partial edentulism provides clinically useful information for dental training and continuing education.

Occlusion of artificial teeth in partial dentures in the "chewing center"--first exploratory population-based evaluations.

Occlusal performance is a substantial determinant of the quality of dental prosthetic restorations. In the follow-up (SHIP 1) to the Study of Health in Pomerania (SHIP), a representative population of 3300 subjects was studied in the first exploratory evaluation of the occlusion of artificial teeth in the chewing center (first molar region) of partial dentures. A digital analysis of interocclusal records of habitual intercuspation position (ICP) was performed using the Greifswald Digital Analyzing System (GEDAS), a software package that identifies contact points as transparent areas. 562 subjects (280 men aged 61.7 ± 11.9 years and 282 women aged 60.7 ± 10.7 years) had maxillary removable partial dentures (RPDs), and 619 (271 men aged 65.0 ± 11.5 years and 348 women aged 62.4 ± 10.6 years) had mandibular RPDs. Most RPDs were retained with either attachment retainers (11.7% maxilla, 11.7% mandible), cast clasps (38.4% maxilla, 40.7% mandible), telescopes with double crowns (15.7% maxilla, 19.1% mandible), or wrought wire clasps (16.4% maxilla, 8.2% mandible). Some had a combination of different retention elements. The mean number of artificial teeth was 7.8 ± 2.9 in the maxilla and 7.5 ± 3.0 in the mandible. Only the artificial teeth (first molars) in mandibular partial dentures showed differences in the frequency of occlusal contacts between groups (chi-square test). Of these, telescopic crown-retained RPDs had the highest frequency of occlusal contacts (74.4% at tooth 36 and 77.1% at tooth 46), and wrought wire-retained RPDs had the lowest (48.4% at tooth 36 and 45.2% at tooth 46). The results for RPDs with a free-end saddle were comparable and analogous; contact frequencies for those with an interdental saddle did not differ significantly. Notably, the overall frequency of occlusal contacts was greater for tooth 46 (62.9%) than for tooth 36. In conclusion, when replacing teeth in the chewing center, particularly in the mandible, telescopic crown-retained RPDs offer a distinct advantage in terms of occlusal contacts and thus provide better occlusal stability.

Use of implant-supported prostheses in edentulous mandibles among prosthodontists in Sweden.

The aim of this study was to investigate the production of mandibular implant-supported fixed and removable prostheses among prosthodontic specialists in Sweden and to compare the results with findings in a similar study made in 2001 (17). Questionnaires regarding treatment with mandibular implant prostheses during 20011 were mailed to all specialists in prosthodontics in Sweden (n = 156, according to available data). Of the 156 questionnaires, 129 (83%) were returned and of those 114 were completed. The reported number of treatments with mandibular implant-supported prostheses varied much among the specialists. Fixed implant prostheses were more common than overdentures (means 11 and 3, median values 8 and 2, respectively). However, the range was large for both alternatives. Ten (9%) of the specialists reported no treatment with fixed implant prostheses while 29 (25%) had not made any implant overdenture during 2011. The most common anchorage system for overdentures in 2011 (as well as in 2001) was two un-splinted implants with ball attachments or Locator abutments. The most common reasons for choosing overdenture treatment instead of a fixed implant prosthesis in 2011 were the reduced cost and the patient's main wish to improve denture retention. A majority of the prosthodontists (58%) reported that patients with implant overdentures were as satisfied as those with fixed implant-supported prostheses, whereas 40% claimed they were less satisfied. Two respondents (2%) considered that overdenture patients were more satisfied than those with a fixed prosthesis. It can be concluded that the general attitude among Swedish prosthodontists towards implant overdentures has not changed much during the 10-year period between the present and the previous investigation.An overdenture is still a seldom-used option in implant treatment of patients with edentulous mandibles in Sweden. Instead, a fixed implant-supported prosthesis continues to be the preferred option,

A practice-based study on the survival of restored endodontically treated teeth.

INTRODUCTION: This retrospective study evaluated the survival of endodontically treated teeth (ETTs) and investigated factors influencing restoration and tooth survival. METHODS: Data from 795 ETTs were recorded, and success (restoration still intact) and survival (restoration intact or failed/repaired/replaced and tooth still in situ) were analyzed using Kaplan-Meier statistics. A multivariate Cox regression analysis was performed to assess the variables influencing success and survival. RESULTS: At the end of the observation period (mean observation time = 4.48 years), 45 teeth had been extracted (annual failure rate for survival = 1.9% at 9.6 years) and 114 restorations had received a restorative follow-up treatment (annual failure rate for success = 4.9% at 9.6 years). CONCLUSIONS: ETTs showed acceptable survival and success in the long-term. Variables showing significant influence on survival were the number of teeth in the dentition and the presence of decay at the moment the patient entered the practice.

Prevalence and risk factors for peri-implant disease in Belgian adults.

OBJECTIVES: This study aimed to evaluate in a Belgian population the frequence of mucositis and peri-implantitis in patients with implants of at least 5 years of function. Another outcome was to access implants/patients characteristics as possible risk indicators for peri-implantitis. MATERIAL AND METHODS: One hundred and three patients (38 males/65 females) with a total of 266 implants were examined. Implants had been inserted in university hospitals as well as in private clinics and the mean time of implants in function was 8.5 years (±3.2). The average patients' age within the population was 62 years (±13.4). General health informations were recorded as well as habits regarding smoking, maintenance visits and oral hygiene. Full mouth clinical parameters (PlI, BoP, PPD) were assessed and radiographs taken to determine the periodontal status and implants diagnosis. RESULTS: Prevalences of mucositis and peri-implantitis at the patient's level were respectively 31% and 37%. They were 38% and 23% at the implant's level. Subjects older than 65 years (OR = 1.39) and those with active periodontitis (OR = 1.98) were prone to peri-implantitis. The association was stronger for hepatitis (OR = 2.92) and totally edentulous patients (OR = 5.56). Finally, at the implant's level, a significant correlation was found in the multi-level analyses between rough surfaces, overdentures and peri-implantitis. CONCLUSION: After 8.5 years an important proportion (±60%) of implants presented biological complications. Furthermore, a positive correlation was showed between age, periodontitis, absence of teeth, rough surfaces and peri-implantitis. Consequently, patients with such characteristics should be informed before implant placement and frequently re-called after for maintenance visits.

An inventory of mandibular fractures associated with implants in atrophic edentulous mandibles: a survey of Dutch oral and maxillofacial surgeons.

PURPOSE: The present study provides an inventory of the number of fractures that occurred in conjunction with implant placement in edentulous patients in the Dutch population from 1980 to 2007 and estimates the incidence with which this might occur. The study also sought to define the factors that increase the risk of fracture. MATERIALS AND METHODS: Questionnaires were sent to all 198 oral and maxillofacial surgeons working in 56 hospitals in the Netherlands. Questions were asked regarding the causes of fractures, the height of the edentulous mandible, and the methods of fracture treatment. RESULTS: Responses were received from 53 of the 56 departments. During the study period, 157 edentulous mandibles fractured in conjunction with implant treatment. All fractures occurred in mandibles with less than 10 mm of height, as measured in the symphysis. An incidence of less than 0.05% was estimated based on an estimated number of 475,000 patients treated with at least two implants during this time to support an overdenture. Reasons for early implant failures were insufficient bone volume, iatrogenic causes, nonintegration, and a narrow arch. Peri-implantitis, trauma, and explantation were associated with fractures occurring 1 year or more after implant placement. Several methods were employed to treat the fractured mandibles, including closed reduction, rigid fixation using osteosynthesis plates, and bone grafts with fixation. In 52% of patients, fracture healing was uneventful; however, in 48% of patients, complications were encountered, including osteomyelitis, nonunion, plate fracture, screw loosening, and dehiscences with subsequent infections. CONCLUSIONS: Mandibles with a height of 10 mm or less, as measured at the symphysis, are at risk of fractures and associated complications. The provision of proper informed consent regarding the advantages and disadvantages of placing implants in thin mandibles is essential.

Satisfaction of patients fitted with implant-retained overdentures

Objective: to evaluate patient satisfaction with implant-retained overdentures, and its relationship with age, sex,period of follow-up, the rehabilitated jaw (maxilla, mandible or both), number of implants, splinting, type of attachmentand the antagonist.Material and methods: the study comprised patients with overdentures fitted betweenJanuary 1996 and June 2007, and with a minimum follow-up of one year. Data regarding patients and prostheseswere collected. The patients indicated their overall satisfaction on a visual analogue scale (VAS) from 0 to 10,as well as satisfaction for individual items such as aesthetics, speech, mastication, prosthetic stability and selfesteem.These data were collected one month after fitting the prostheses, at 12 months and at a final examination.Statistical analyses were made using the SPSS version 15, statistical significance was considered for p<0.05.Results:the study included 95 patients, 43 men and 52 women, with a mean age of 55.9 years; 76 edentulous mandiblesand 31 edentulous maxillae were rehabilitated with 107 overdentures. One hundred and thirty-seven implantswere placed in the maxilla, and 224 in the mandible. The mean level of overall satisfaction was 9 at one month offitting the prosthesis, 8.8 at 12 months and 8.7 at the final control (mean 71 months).Conclusions: the patients fittedwith implant-retained overdentures expressed a high level of overall satisfaction, independently of age, sex, lengthof follow-up, rehabilitated jaw, number of implants per overdenture, whether splinted or non-splinted, and type ofattachment. Men were more satisfied with mastication and stability (AU)

Tooth-related risk factors for periodontal disease in community-dwelling elderly people.

OBJECTIVE: While most previous epidemiological studies have focused on subject-level risk factors for periodontal destruction, tooth-related factors have not been fully explored. The purpose of this study was to evaluate both tooth-related and subject-related factors affecting periodontal disease progression using a two-level multilevel model. MATERIAL AND METHODS: A longitudinal survey over a period of 10 years was carried out on 286 community-dwelling elderly subjects aged 70 years at baseline. Clinical attachment level (CAL) was measured at six sites per tooth on all teeth present and periodontal disease progression was defined as CAL> or =3 mm. RESULTS: Periodontal disease progression was found in 79% of the subjects and most frequently in maxillary molars. Multilevel logistic regressions revealed that subjects wearing removable dentures were significantly at risk for periodontal disease progression. Abutment teeth for removable/fixed dentures were also significantly more likely to suffer periodontal breakdown. Furthermore, the following tooth-related variables were found to be possible risk factors for periodontal disease progression: maxillary and multirooted teeth. CONCLUSION: Multirooted teeth and abutments for a fixed denture were possible risk factors for periodontal disease progression.

Demographics of implant placement and complications of a patient subgroup in a dental hospital population.

STATEMENT OF PROBLEM: Little has been reported about the demographics of implant placement in the Irish population and the complications that occur. This is important in terms of service planning and providing patient information. PURPOSE: The purpose of this study was to construct a database of patients who had implants placed in the Dublin Dental School et Hospital from 2000 to 2006. Also, we wanted to compare the complications that occurred in patients who had overdentures to those with a fixed prosthesis. METHODS: Hospital records were searched for all patients who had implants placed over a seven-year period and we recorded demographic information, as well as details of the implant site, implant type and restoration. Patients who had four or more implants placed for an implant-supported overdenture or fixed prosthesis were invited to attend for a clinical examination. RESULTS: A total of 1,111 implants were placed in 452 patients over the study period--half of the implants supported single crowns, while the other half supported mainly overdentures and full arch fixed prostheses, with few fixed partial dentures. The 40- to 60-year-olds had the greatest number of implants placed of any age group and most implants were placed in the anterior region. Patients with implant-supported overdentures recorded more complications (52%) compared to those with fixed prostheses (32%). The most common complications associated with both treatments were gingival inflammation and peri-implant mucositis. Overdentures additionally had a significant number of retentive clip fractures. CONCLUSIONS: Implant-supported overdentures and fixed prostheses were both clinically successful. However, patients and clinicians should be aware that soft tissue and mechanical complications are common.