Ten-year clinical performance of zirconia posterior fixed partial dentures.

BACKGROUND: With the constantly increasing demand for metal-free solutions in dental therapy, numerous ceramic restorations have found their way into everyday clinical practice, but long-term clinical data are limited. OBJECTIVE: The aim of this prospective clinical study was to evaluate three- and four-unit fixed partial dentures in the posterior region made of zirconium dioxide frameworks veneered with feldspathic porcelain after 10 years in clinical use. METHODS: Based on the two studies published in 2009 and 2012, in which the all-ceramic FDPs were evaluated after 3 and 5 years of function, a clinical evaluation of a total of 17 restorations after 10 years with regard to their condition and long-term stability was carried out in the course of this study. The restorations were fabricated using feldspathic ceramic-veneered, yttria-stabilised, tetragonal zirconium dioxide as the framework material. The data collection was based on modified CDA criteria and included, for example, the shape, shade, surface condition and the success and survival rates of the restorations. RESULTS: The all-ceramic prostheses embodied excellent biocompatibility and colour reproduction. As a result of an increased incidence of chipping fractures, the success rate was 60%. The survival rate, however, was 88.2%, as 2 of the 17 restorations were lost. CONCLUSION: All-ceramic concepts for FDP constructions in the posterior region achieved satisfactory results in terms of durability after 10 years. The main problem was chipping, as has been generally recognised. Nevertheless, the materials were characterised by excellent aesthetics and biocompatibility, which ultimately makes them a good alternative to conventional restorative options. TRIAL REGISTRATION: This study is registered in DRKS-German Clinical Trials Register with the register number DRKS00021743.

Long-term Outcome of Speech Intelligibility in Maxillary Dental Rehabilitation with Full Dentures: A Prospective Study Using Automatic Speech Quantification.

AIMS: Complete maxillary edentulism and prosthetic rehabilitation with removable full dentures are known to affect speech intelligibility. The aim of this study was to prospectively investigate the long-term effect of time on speech intelligibility in patients being rehabilitated with newly fabricated full maxillary dentures. MATERIALS AND METHODS: Speech was recorded in a group of 14 patients (male = 9, female = 5; mean age ± standard deviation [SD] = 66.14 ± 7.03 years) five times within a mean period of 4 years (mean ± SD: 47.50 ± 18.16 months; minimum/maximum: 24/68 months) and in a control group of 40 persons with healthy dentition (male = 30, female = 10; mean age ± SD = 59 ± 12 years). All 14 participants had their inadequate removable full maxillary dentures replaced with newly fabricated dentures. Speech intelligibility was measured by means of a polyphone-based speech recognition system that automatically computed the percentage of accurately spoken words (word accuracy [WA]) at five different points in time: 1 week prior to prosthetic maxillary rehabilitation (both with and without inadequate dentures in situ) and at 1 week, 6 months, and a mean of 48 months after the insertion of newly fabricated full maxillary dentures. RESULTS: Speech intelligibility of the patients significantly improved after 6 months of adaptation to the new removable full maxillary dentures (WA = 66.93% ± 9.21%) compared to inadequate dentures in situ (WA = 60.12% ± 10.48%). After this period, no further significant change in speech intelligibility was observed. After 1 week of adaptation, speech intelligibility of the rehabilitated patients aligned with that of the control group (WA = 69.79% ± 10.60%) and remained at this level during the examination period of 48 months. CONCLUSION: The provision of new removable full maxillary dentures can improve speech intelligibility to the level of a healthy control group on a long-term basis.

Influence of gender of the teaching staff on students' acceptance of a virtual implant planning course.

Acceptance of new technology is influenced by a number of situational and social factors. So far, only limited data are available on the influence of the teaching staff's gender on the acceptance of virtual dental implant planning by students. This study aimed at assessing the influence of the teaching staff's gender on the acceptance of a virtual implant planning course by male and female undergraduate dental students and their general attitude toward implantology. Two groups of third-year dental students (group 1, 9 males, 22 females; group 2, 12 males, 20 females) attended a virtual dental implant planning course. For the first group the teaching staff was all-male, while the teaching staff was all-female for the second group. After completion of the course the students filled in a technology acceptance questionnaire. An all-female teaching staff led to a degree of technology acceptance that did not differ significantly for male and female students. When the teaching staff was all-male, significant differences for technology acceptance occurred between male and female students. However, male as well as female students attributed the practice of implantology to both genders of dentists, equally, without statistically significant difference independent of the gender of the teaching staff. The more evenly distributed degree of technology acceptance of students of both genders being taught by a female staff is a favorable effect which may be explained by the more egalitarian style of women. Therefore, while feminization in dentistry proceeds, adequate measures should be taken to increase the number of female teachers.

Case History Report: Immediate Rehabilitation with a Prefabricated Fibula Flap Following Removal of a Locally Aggressive Maxillary Tumor.

The present clinical case history report describes an interdisciplinary treatment protocol that combines maxillary tumor resection with immediate reconstruction to achieve functional rehabilitation. A fibula flap that received four dental implants and a split-thickness graft epithelial layer was prefabricated for a 31-year-old man. The flap was designed so that it could be adapted to fit in different extents of tumor resection. Resection and immediate reconstruction were successfully performed 6 weeks after flap prefabrication, with the final bar-retained dental prosthesis delivered 4 weeks later.

Masticatory Rehabilitation of a Patient With Cleft Lip and Palate Malformation Using a Maxillary Full-Arch Reconstruction With a Prefabricated Fibula Flap.

For full-arch reconstruction of an atrophied cleft maxilla with missing premaxilla, a prefabricated microvascular free bony flap is a relevant option. A fibula flap was prefabricated in a cleft patient who received six dental implants and an epithelial layer. Six weeks later, maxillary reconstruction was performed. The inpatient period could be confined to 2 weeks. A fixed provisional prosthesis was delivered after an additional 2 weeks. A prefabricated flap allows for the reduction of the interval without a dental prosthesis to only a few weeks, even when a complex full-arch reconstruction of the maxilla is required.

A new, highly precise measurement technology for the in vitro evaluation of the accuracy of digital imaging data.

OBJECTIVES: Three-dimensional radiological imaging data play an increasingly role in planning, simulation, and navigation in oral and maxillofacial surgery. The aim of this study was to establish a new, highly precise, in vitro measurement technology for the evaluation of the geometric accuracy down to the micrometric range of digital imaging data. MATERIAL AND METHODS: A macerated human mandible was scanned optically with an industrial, non-contact, white light scanner, and a three-dimensional (3D) model was obtained, which served as a master model. The mandible was then scanned 10 times by cone beam computed tomography (CBCT), and the generated 3D surface bone model was virtually compared with the master model. To evaluate the accuracy of the CBCT scans, the standard deviation and the intraclass coefficient were determined. RESULTS: A total of 19 measurement points in 10 CBCT scans were investigated, and showed an average value of 0.2676 mm with a standard deviation of 0.0593 mm. The standard error of the mean was 0.0043 mm. The intraclass correlation coefficient (ICC) within the 10 CBCT scans was 0.9416. CONCLUSIONS: This highly precise measuring technology was demonstrated to be appropriate for the evaluation of the accuracy of digital imaging data, down to the micrometric scale. This method is able to exclude human measurement errors, as the software calculates the superimposition and deviation. Thus inaccuracies caused by measurement errors can be avoided. This method provides a highly precise determination of deviations of different CBCT parameters and 3D models for surgical, navigational, and diagnostic purposes. Thus, surgical procedures and the post-operative outcomes can be precisely simulated to benefit the patient.

Lingual concavities in the mandible: a morphological study using cross-sectional analysis determined by CBCT.

BACKGROUND: Lingual undercuts are common in the edentulous mandible and pose the risk of perforating the lingual cortical bone during insertion of dental implants, which may lead to hemorrhage or infections of the parapharyngeal space. The aim of our study was to determine the occurrence and extent of lingual undercuts in the molar and premolar/canine region of the mandible. METHODS: We analyzed 716 cross-sections of the edentulous molar region and 215 cross-sections of the edentulous first premolar/canine region. Mandibular morphology was classified into a U-configuration (undercut), P-configuration (parallel), and C-configuration (convex), depending on the shape of the alveolar ridge. Depth of the lingual concavity, concavity angle, and further parameters were measured to describe the mandibular morphology. RESULTS: Lingual undercuts had a prevalence of 68% in the molar region. The prevalence was significantly higher in the second molar region (90%) than in the first molar region (56%). A deep position of the inferior alveolar nerve close to the basal cortical bone was significantly associated with the presence of lingual undercuts. CONCLUSION: Lingual undercuts are a frequent in the edentulous mandible. Cross-sectional analysis of three-dimensional radiographs provides the opportunity to determine a lingual undercut and to prevent complications of perforating the lingual cortical bone.

3-D based minimally invasive one-stage lateral sinus elevation - a prospective randomized clinical pilot study with blinded assessment of postoperative visible facial soft tissue volume changes.

OBJECTIVE: The purpose of this prospective and randomized clinical study was to assess differences in patient morbidity between minimally invasive lateral sinus elevation (study group, n = 14) and conventional one-stage lateral sinus elevation (control group, n = 12). It was hypothesized that trauma to soft tissue was reduced in the study group. MATERIALS AND METHODS: Optical 3-D imaging was assessed blinded on days 1 and 7 after surgery to determine the visible soft tissue swelling of the upper lip and cheeks. Postoperative pain and discomfort were evaluated by a visual analogue scale (VAS; scale 0-10). RESULTS: Immediately and on day 1 after surgery, the study group patients rated pain and discomfort as 2.4 [SD 1.7] and 3.1 [SD 2.1], respectively, on the VAS; while, the controls rated 4 [SD 1.6] and 5.6 [SD 1.7], respectively. The mean facial soft tissue volume change, assessed on day 1 after surgery, was 5.0 cm(3) [range: 0.2-9.2] for the study group and 15.5 cm(3) (9.3-21.55) for the controls (p = 0.00). CONCLUSIONS: Despite the small number of patients in this prospective study, 3-D based minimally invasive one-stage lateral sinus elevation resulted in favourable patient morbidity with less postoperative visible facial soft tissue volume changes.

Speech intelligibility enhancement after maxillary denture treatment and its impact on quality of life.

PURPOSE: Tooth loss and its prosthetic rehabilitation significantly affect speech intelligibility. However, little is known about the influence of speech deficiencies on oral health-related quality of life (OHRQoL). The aim of this study was to investigate whether speech intelligibility enhancement through prosthetic rehabilitation significantly influences OHRQoL in patients wearing complete maxillary dentures. Speech intelligibility by means of an automatic speech recognition system (ASR) was prospectively evaluated and compared with subjectively assessed Oral Health Impact Profile (OHIP) scores. MATERIALS AND METHODS: Speech was recorded in 28 edentulous patients 1 week prior to the fabrication of new complete maxillary dentures and 6 months thereafter. Speech intelligibility was computed based on the word accuracy (WA) by means of an ASR and compared with a matched control group. One week before and 6 months after rehabilitation, patients assessed themselves for OHRQoL. RESULTS: Speech intelligibility improved significantly after 6 months. Subjects reported a significantly higher OHRQoL after maxillary rehabilitation with complete dentures. No significant correlation was found between the OHIP sum score or its subscales to the WA. CONCLUSION: Speech intelligibility enhancement achieved through the fabrication of new complete maxillary dentures might not be in the forefront of the patients' perception of their quality of life. For the improvement of OHRQoL in patients wearing complete maxillary dentures, food intake and mastication as well as freedom from pain play a more prominent role.

Complex hemimaxillary rehabilitation with a prefabricated fibula flap and cast-based vacuum-formed surgical template.

This report describes a complex, surgical, and prosthodontic hemimaxillary rehabilitation with a prefabricated vascularized free fibula graft. The treatment was based on 3-dimensional skull and fibula models but avoided software-based virtual planning of the reconstructive procedure or the implant positions. Cast-based surgical guides were used for implant placement during prefabrication of the fibula graft and for the positioning of the prefabricated graft in the maxilla during the reconstructive procedure. This procedure allowed the definitive prosthesis to be attached to the implants of the reconstructed maxilla during the inpatient period.

A 5-year prospective radiographic evaluation of marginal bone levels adjacent to parallel-screw cylinder machined-neck implants and rough-surfaced microthreaded implants using digitized panoramic radiographs.

OBJECTIVE: The purpose of this split-mouth study was to compare macro- and microstructure implant surfaces at the marginal bone level over five years of functional loading. MATERIALS AND METHODS: From January to February 2006, 133 implants (70 rough-surfaced microthreaded implants and 63 machined-neck implants) were inserted in the mandible of 34 patients with Kennedy Class I residual dentitions and followed until December 2011. Marginal bone level was radiographically determined at six time points: implant placement (baseline), after the healing period, after six months, and at two years, three years, and five years follow-up. RESULTS: Median follow-up time was 5.2 years (range: 5.1-5.4). The machined-neck group had a mean crestal bone loss of 0.5 mm (0.0-2.3) after the healing period, 1.1 mm (0.0-3.0) at two years follow-up, and 1.4 mm (0.0-2.9) at five years follow-up. The rough-surfaced microthreaded implant group had a mean bone loss of 0.1 mm (-0.4 to 2.0) after the healing period, 0.5 mm (0.0-2.1) at two years follow-up, and 0.7 mm (0.0-2.3) at five years follow-up. The two implant types showed significant differences in marginal bone levels. CONCLUSIONS: Rough-surfaced microthreaded design caused significantly less loss of crestal bone levels under long-term functional loading in the mandible when compared to machined-neck implants.

Acceptance of virtual dental implant planning software in an undergraduate curriculum: a pilot study.

BACKGROUND: Advances in healthcare such as virtual dental implant planning have the capacity to result in greater accuracy, speed, and efficiencies leading to improvement in patient care. It has been suggested that the acceptance of new technology is influenced by a variety of factors including individual differences, social and situational influences, user beliefs, and user attitudes. Despite the large volume of work in this area, only limited research has been conducted in the field of dental education. Therefore, the present study aimed at assessing the acceptance of virtual dental implant planning software by undergraduate students. METHODS: Forty-three third-year dental students of the University of Erlangen-Nuremberg, Germany, were included in the study. They filled in a questionnaire based on a combination of the technology acceptance model and the theory of planned behavior (C-TAM-TPB). Cronbach's α, Pearson product moment correlation coefficients, and squared multiple correlations (R2) were calculated. RESULTS: Cronbach's α exceeded .7 for all constructs. Pearson correlations were significant for the pairs perceived usefulness/behavioral intention, perceived usefulness/attitude, and attitude/behavioral intention. Perceived ease of use explained .09% of the variance of perceived usefulness (R2 = .09). Perceived ease of use and perceived usefulness accounted for 31% of the variance of attitude (R2 = .31). Perceived usefulness, attitude, subjective norm, and perceived behavioral control explain 37% of the variance of behavioral intention (R2 = .37). CONCLUSIONS: Virtual dental implant planning software seems to be accepted by dental students especially because of its usefulness and the students' attitude towards this technology. On the other hand, perceived ease of use does not play a major role. As a consequence, the implementation of virtual dental implant planning software in a dental undergraduate curriculum should be supported by highlighting the usefulness by the supervisors, who should also strengthen the attitude of the students towards this technology.

Spaced education activates students in a theoretical radiological science course: a pilot study.

BACKGROUND: The present study aimed at determining if the addition of spaced education to traditional face-to-face lectures increased the time students kept busy with the learning content of a theoretical radiological science course. METHODS: The study comprised two groups of 21 third-year dental students. The students were randomly assigned to a "traditional group" and a "spaced education group". Both groups followed a traditional face-to-face course. The intervention in the spaced education group was performed in way that these students received e-mails with a delay of 14 days to each face-to-face lecture. These e-mails contained multiple choice questions on the learning content of the lectures. The students returned their answers to the questions also by e-mail. On return they received an additional e-mail that included the correct answers and additional explanatory material.All students of both groups documented the time they worked on the learning content of the different lectures before a multiple choice exam was held after the completion of the course. All students of both groups completed the TRIL questionnaire (Trierer Inventar zur Lehrevaluation) for the evaluation of courses at university after the completion of the course. The results for the time invested in the learning content and the results of the questionnaire for the two groups were compared using the Mann-Whitney-U test. RESULTS: The spaced education group spent significantly more time (216.2 ± 123.9 min) on keeping busy with the learning content compared to the traditional group (58.4 ± 94.8 min, p < .0005). The spaced education group rated the didactics of the course significantly better than the traditional group (p = .034). The students of the spaced education group also felt that their needs were fulfilled significantly better compared to the traditional group as far as communication with the teacher was concerned (p = .022). CONCLUSIONS: Adding spaced education to a face-to-face theoretical radiological science course activates students in a way that they spend significantly more time on keeping busy with the learning content.

Expression of interleukin 6 and tumor necrosis factor alpha in soft tissue over ceramic and metal implant materials before uncovering: a clinical pilot study.

PURPOSE: To compare the effect of ceramic and metal implant materials on the expression pattern of inflammatory cytokines in peri-implant soft tissue. MATERIALS AND METHODS: This split-mouth study included patients who received dental implants. In each patient, four different materials were used for the implant cover screws: the ceramic material titanium niobium oxynitride ([Ti,Nb]ON) with plasma-chemical oxidation treatment, (Ti,Nb)ON, a titanium-tantalum alloy, and tantalum. Biopsy specimens of peri-implant tissue were harvested at reentry, 4 months after the initial surgery. Immunohistochemical staining was performed for tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). RESULTS: Six patients received a total of 24 dental implants with the four different types of implant cover screws. Quantitative analysis of TNF-α; and IL-6 expression showed the lowest expression of IL-6 (1.5; interquartile range, 0 to 8.5) and TNF-α (4.8; interquartile range, 3.5 to 7.5) in tissue adjacent to the (Ti,Nb)ON layer. In comparison to the metal surfaces, the expression of both cytokines was significantly lower (P = .01 and P = .03). CONCLUSIONS: The lowest levels of cytokine expression were observed in tissue adjacent to the ceramic (Ti,Nb)ON coating with plasma-chemical oxidation. Based on the results of this study, this ceramic layer shows promise as a biocompatible material, and further study is warranted.

Acceptance of technology-enhanced learning for a theoretical radiological science course: a randomized controlled trial.

BACKGROUND: Technology-enhanced learning (TEL) gives a view to improved education. However, there is a need to clarify how TEL can be used effectively. The study compared students' attitudes and opinions towards a traditional face-to-face course on theoretical radiological science and a TEL course where students could combine face-to-face lectures and e-learning modules at their best convenience. METHODS: 42 third-year dental students were randomly assigned to the traditional face-to-face group and the TEL group. Both groups completed questionnaires before the beginning and after completion of the course on attitudes and opinions towards a traditional face-to-face lectures and technology-enhanced learning. After completion of the course both groups also filled in the validated German-language TRIL (Trierer Inventar zur Lehrevaluation) questionnaire for the evaluation of courses given at universities. RESULTS: Both groups had a positive attitude towards e-learning that did not change over time. The TEL group attended significantly less face-to-face lectures than the traditional group. However, both groups stated that face-to-face lectures were the basis for education in a theoretical radiological science course. The members of the TEL group rated e-mail reminders significantly more important when they filled in the questionnaire on attitudes and opinions towards a traditional face-to-face lectures and technology-enhanced learning for the second time after completion of the course. The members of the technology-enhanced learning group were significantly less confident in passing the exam compared to the members of the traditional group. However, examination results did not differ significantly for traditional and the TEL group. CONCLUSIONS: It seems that technology-enhanced learning in a theoretical radiological science course has the potential to reduce the need for face-to-face lectures. At the same time examination results are not impaired. However, technology-enhanced learning cannot completely replace traditional face-to-face lectures, because students indicate that they consider traditional teaching as the basis of their education.

Esthetics and psyche-part 1: assessment of the influence of patients' perceptions of body image and body experience on selection of existing natural tooth color.

PURPOSE: The aim of this research was to test the hypothesis that patients' attitudes toward their body affect their capacity to accurately select their existing natural tooth color. MATERIALS AND METHODS: Standard validated psychologic assessments were used to determine a person's perception of body image and experience. Oral images were compared with the patients' perceptions of their natural tooth color, which were then compared with the actual tooth color judged by a dental professional. RESULTS: For the vital body dynamic and disliking body experience subscales, women exhibited a significantly more negative attitude toward their bodies than men (P = .000). Patients with a negative attitude toward their body tended to choose a lighter tooth color. The correlation between patients' and the testing physician's choices of color was r = 0.540 for women and r = 0.746 for men. CONCLUSIONS: Unhappiness with body image and experience results in poor perception of a patient's own oral image, which in turn results in a patient perceiving that his or her natural tooth color is lighter than that judged by a dental professional. This has clinical implications when trying to achieve patient satisfaction with dental prostheses.

Speech intelligibility enhancement through maxillary dental rehabilitation with telescopic prostheses and complete dentures: a prospective study using automatic, computer-based speech analysis.

PURPOSE: A completely edentulous or partially edentulous maxilla involving missing anterior teeth may impact speech production and lead to reduced speech intelligibility. The aim of this study was to prospectively evaluate the effect of a dental prosthetic rehabilitation on speech intelligibility in patients with a toothless or interrupted maxillary arch by means of an automatic, standardized speech recognition system. MATERIALS AND METHODS: The speech intelligibility of 45 patients with complete tooth loss or a loss including missing anterior teeth in the maxilla was evaluated by means of a polyphone-based automatic speech recognition system that assessed the percentage of correctly recognized words (word accuracy). To replace inadequate maxillary removable dentures, 20 patients from the overall sample had been rehabilitated with complete dentures and 25 patients with telescopic prostheses. Speech recordings were made in four recording sessions (with and without existing prostheses and then at 1 week and 6 months after placement of newly fabricated prostheses). RESULTS: Significantly higher speech intelligibility was observed in both patient groups compared to the original results without the dentures inserted. After 6 months of adaptation, both groups had reached a level of speech quality that was comparable to the healthy control group. However, patients receiving new telescopic prostheses showed significantly higher levels of speech intelligibility compared to those receiving new complete dentures. Within 6 months, speech intelligibility did not significantly improve from the level found 1 week after insertion of new prostheses for both groups. CONCLUSION: Patients benefit from the fabrication of new dentures in terms of speech intelligibility, regardless of the type of prosthesis. However, telescopic crown prostheses yield significantly better speech quality compared to complete dentures.

Awareness and education of patients receiving bisphosphonates.

BACKGROUND: Bisphosphonates are used to fight osteoporosis and for treating malignancies. In 2003, the first case reports appeared that described bisphosphonate-induced osteonecrosis of the jaw (BONJ). The aim of this study was to assess patient awareness of the adverse effects of bisphosphonates in order to improve cooperation among doctors and between doctors and patients. METHODS: Patients with symptoms of osteoporosis, prostate cancer, or breast cancer were surveyed to determine their knowledge of bisphosphonates. The questionnaire comprised 12 questions that covered sociographic data, kind of medication, level of information, and side effects experienced. Out of 142 patients contacted, 55 participated in the study. RESULTS: 62% of patients received most of their knowledge about the prescribed drug from the package insert. Despite knowledge that the patient was under treatment with bisphosphonates, 80% of dental treatments were continued without modifications. Only 32% of patients that received intravenous bisphosphonate treatment were aware of the possible risks of developing BONJ. CONCLUSION: The level of information is poor concerning the side effects of bisphosphonates, particularly the risk of BONJ. Clinicians should aim to sensitize the relevant people about the risks before treatment.

Oral health-related quality of life and implant therapy: an evaluation of preoperative, intermediate, and post-treatment assessments of patients and physicians.

INTRODUCTION: Little is known about the impact of different stages of implant therapy on oral health-related quality of life (OHRQoL). The aim of this study was to assess OHRQoL before, during, and after completion of prosthodontic implant therapy by patients and treating physicians, who were predicted to evaluate OHRQoL in different ways. MATERIAL AND METHODS: Over a period of six months, 16 randomly selected patients were assessed for OHRQoL with a German version of the Oral Health Impact Profile (OHIP-G, range 0-220). Patients assessed themselves before surgery, during the period of complete osseointegration, and after prosthodontic treatments. Additionally, physicians assessed OHRQoL and OHIP subscales with a visual analogue scale. RESULTS: Patients reported significant changes in median OHIP scores (preoperative: 76.5; healing period: 84.3; postoperative: 29.5; p<0.01), as did physicians (preoperative: 7.1; postoperative: 2; p<0.01). The most prevalent patient-reported problem was "worried" (subscale: psychological discomfort), whereas the subscale "functional limitation" was identified most frequently by physicians. CONCLUSION: Preoperative, intermediate, and post-treatment assessments of OHRQoL exhibited significantly different OHIP scores. In contrast to the physicians' assessments, the most unfavourable OHIP scores were reported by patients during the healing period, while the psychological dissatisfaction OHIP subscale represented the most important patient factor.

Five-year clinical follow-up of prefabricated precision attachments: a comparison of uni- and bilateral removable dental prostheses.

OBJECTIVES: To evaluate the clinical long-term success of prefabricated precision attachments in retaining uni- or bilateral removable dental prostheses. METHOD AND MATERIALS: Twenty-three patients with uni- or bilateral shortened dental arches received removable dental prostheses attached to the residual dentition with two types of precision attachments. RESULTS: After 5 years, 70% of bilateral and 25% of unilateral removable dental prostheses remained clinically functional. The most frequent cause of clinical failure was fracture of the abutment teeth for bilateral partial dentures and irreversible wear of the precision attachment for unilateral prostheses. Oral hygiene status significantly improved, and the mean pocket depth of the abutment teeth did not increase after 5 years. CONCLUSION: Removable partial denture prostheses, retained bilaterally with precision attachments, are a reliable treatment modality without negative long-term effects on periodontal health, whereas unilateral removable dental prostheses cannot be recommended because of high clinical failure rates.