Cost estimation of single-implant treatment in the periodontally healthy patient after 16-22 years of follow-up.

BACKGROUND: Costs for single-implant treatment are mostly described for the initial treatment. Information on the additional cost related to aftercare is scarce. OBJECTIVE: To make an estimation of complication costs of single implants in periodontally healthy patients after 16-22 years and to compare costs for various prosthetic designs. MATERIALS AND METHODS: Patients with a single implant were recalled for a clinical examination and file investigation. Prosthetic designs included single-tooth (ST) and CeraOne (CO) abutments supporting a porcelain-fused-to-metal (PFM), all-ceramic (CER), or gold-acrylic (ACR) crown. Costs related to failures or technical, biologic, and aesthetic complications were retrieved from patient's records. Total and yearly additional complication costs were calculated as a percentage relative to the initial cost. Chair time needed to solve the complication was recorded and prosthetic designs were compared by Kruskal-Wallis tests. RESULTS: Fifty patients with 59 surviving implants were clinically investigated. Additional complication costs after a mean follow-up of 18.5 years amounted to 23% (range 0-110%) of the initial treatment cost. In total, 39% of implants presented with no costs, whereas 22% and 8% encountered additional costs over 50% and 75%, respectively. In 2%, the complication costs exceeded the initial cost. The mean yearly additional cost was 1.2% (range 0-6%) and mean complication time per implant was 67 min (range 0-345 min). Differences between prosthetic designs (CO, ST-PFM, ST-ACR) were statistically significant for total cost (P = 0.011), yearly cost (P = 0.023), and time (P = 0.023). Pairwise comparison revealed significant lower costs for CO compared with ST-ACR reconstructions. CONCLUSION: Patients should be informed about additional costs related to complications with single implants. The mean additional cost spent on complications was almost one-quarter of the initial treatment price. A majority of implants presented with lower additional costs, whereas the highest complication costs were related to a smaller group with 22% of the implants needing more than half of the initial cost for complication management. Expenses were significantly different for various prosthetic designs.

General population norms of the Swedish short forms of oral health impact profile.

We reported the development and psychometric evaluation of a Swedish 14-item and a five-item short form of the Oral Health Impact Profile. The 14-item version was derived from the English-language short form developed by Slade in1997. The five-item version was derived from the German-language short form developed by John et al. in 2006. Validity, reliability and normative values for the two short form summary scores were determined in a random sample of the adult Swedish population (response rate: 46%, N = 1366 subjects). Subjects with sufficient OHRQoL information to calculate a summary score (N = 1309) were on average 50·1 ± 17.4 years old, and 54% were women. Short form summary scores correlated highly with the 49-item OHIP-S (r ≥ 0.97 for OHIP-S14, r ≥ 0.92 for OHIP-S5) and with self-report of oral health (r ≥ 0.41). Reliability, measured with Cronbach's alpha (0.91 for OHIP-S14, 0.77 for OHIP-S5), was sufficient. In the general population, 50% of the subjects had ≥2 OHIP-S14 score points and 10% had ≥11 points, respectively. Among subjects with their own teeth only and/or fixed dental prostheses and with partial removable dental prostheses, 50% of the population had ≥2 OHIP-S14 score points, and 10% had ≥11 points. For subjects with complete dentures, the corresponding figures were 3 and 24 points. OHIP-S5 medians for subjects in the three population groups were 1, 1 and 2 points. Swedish 14-item and 5-item short forms of the OHIP have sufficient psychometric properties and provide a detailed overview about impaired OHRQoL in Sweden. The norms will serve as reference values for future studies.

Normative values for the Oro-facial Esthetic Scale in Sweden.

This study reports the findings and challenges of the assessment of oro-facial aesthetics in the Swedish general population and the development of normative values for the self-reporting Orofacial Esthetic Scale (OES). In a Swedish national sample of 1406 adult subjects (response rate: 47%), OES decile norms were established. The influence of sociodemographics (gender, age, and education), oral health status and general health status on OES scores was analysed. Mean ± standard deviation of OES scores was 50.3 ± 15.6 units (0, worst score; 70, best score); <1% of the subjects had the minimum score of 0, and 11% had the maximum score of 70 OES units. Orofacial Esthetic Scale score differences were (i) substantial (>5 OES units) for subjects with excellent/very good versus good to poor oral or general health status; ii) small (2 units), but statistically significant for gender (P = 0.01) and two age groups (P = 0.02), and (iii) absent for subjects with college versus no college education (P = 0.31) or with and without dentures (P = 0.90). To estimate normative values for a self-reporting health status, instrument is considered an important step in standardisation, and the developed norms provide a frame of reference in the general population to interpret the Orofacial Esthetic Scale scores.

Long-term follow-up of turned single implants placed in periodontally healthy patients after 16-22 years: radiographic and peri-implant outcome.

OBJECTIVES: Retrospectively evaluate the survival, radiographic and peri-implant outcome of single turned Brånemark™ implants after at least 16 years. MATERIALS AND METHODS: From 134 patients (C-group), 101 could be contacted concerning implant survival and 50 (59 remaining implants) were clinically examined (I-group). Marginal bone level was radiographically measured from the implant-abutment junction at baseline (=within 6 months after abutment connection) and 1-4, 5-8 and 16-22 years post-operatively. Probing depth, gingival and plaque index were measured. Marginal bone-level changes were analyzed using Friedman's and Wilcoxon's signed ranks tests. Spearman's correlations between radiographic and clinical parameters were calculated. RESULTS: In the C-group, 13 out of 166 implants in 11 out of 134 patients failed (CSR=91.5%). In the I-group (28 males-22 females; mean age 23.9 years at baseline; range 14-57), the mean follow-up was 18.4 years (range 16-22). The mean bone level was 1.7±0.88 mm (range -0.8 to 5) after 16-22 years. Changes in the mean marginal bone level were statistically significant between baseline and the second measuring interval (1-4 years). Thereafter, no significant differences could be demonstrated. The mean interproximal probing depth, gingival and plaque indices were 3.9±1.27 mm, 1.2±0.81 and 0.2±0.48, respectively. Probing depth was moderately correlated with gingival inflammation (r=0.6; P<0.001) but not with bone level (P>0.05). 81.4% of the implants had a bone level ≤2nd thread and 91.5% had a probing depth ≤5 mm. 76.3% had both bone level ≤2nd thread and probing depth ≤5 mm. CONCLUSIONS AND CLINICAL IMPLICATIONS: The single turned Brånemark™ implant is a predictable solution with high clinical survival and success rates. In general, a steady-state bone level can be expected over decades, with minimal signs of peri-implant disease. A minority (5%), however, presents with progressive bone loss.

Implants and/or teeth: consensus statements and recommendations.

In August 23-25, 2007, the Scandinavian Society for Prosthetic Dentistry in collaboration with the Danish Society of Oral Implantology arranged a consensus conference on the topic 'Implants and/or teeth'. It was preceded by a workshop in which eight focused questions were raised and answered in eight review articles using a systematic approach. Twenty-eight academicians and clinicians discussed the eight review papers with the purpose to reach consensus on questions relevant for the topic. At the conference the consensus statements were presented as well as lectures based on the review articles. In this article the methods used at the consensus workshop are briefly described followed by the statements with comments.

Fracture strength of two oxide ceramic crown systems after cyclic pre-loading and thermocycling.

The aim of the present study was to investigate the fracture resistance of zirconia crowns and to compare the results with crowns made of a material with known clinical performance (alumina) in away that reflects clinical aspects. Sixty crowns were made, 30 identical crowns of alumina and 30 of zirconia. Each group of 30 was randomly divided into three groups of 10 crowns that were to undergo different treatments: (i) water storage only, (ii) pre-loading (10 000 cycles, 30-300 N, 1 Hz), (iii) thermocycling (5-55 degrees , 5000 cycles) + pre-loading (10 000 cycles, 30-300 N, 1 Hz). Subsequently, all 60 crowns were subjected to load until fracture occurred. There were two types of fracture: total fracture and partial fracture. Fracture strengths (N) were: group 1, alumina 905/zirconia 975 (P = 0.38); group 2, alumina 904/zirconia 1108 (P < 0.007) and group 3, alumina 917/zirconia 910 (P > 0.05). Total fractures were more frequent in the alumina group (P < 0.01). Within the limitations of this in vitro study, it can be concluded that there is no difference in fracture strength between crowns made with zirconia cores compared with those made of alumina if they are subjected to load without any cyclic pre-load or thermocycling. There is, however, a significant difference (P = 0.01) in the fracture mode, suggesting that the zirconia core is stronger than the alumina core. Crowns made with zirconia cores have significantly higher fracture strengths after pre-loading.

All-ceramic fixed partial dentures designed according to the DC-Zirkon technique. A 2-year clinical study.

The aim of the study was to investigate whether the properties of a pre-sintered, hot isostatic post-compacted (HIP) ZrO2 are adequate for use in three-five-unit fixed partial dentures (FPDs) and to evaluate the clinical results. Twenty three-five-unit FPDs were fabricated for 18 patients on a total of 56 abutments. They were all made on abutments cut with a shoulder preparation and cemented with a zinc phosphate cement. They were clinically followed for 24 months. After 24 months all FPDs were still in use without any fractures or clinical wear but in three cases (15%) minor chip-of fractures were observed. Marginal integrity was rated excellent at 45 abutments and acceptable at 11. Within the limitations of this 2-year clinical follow-up study, FPDs made of pre-sintered HIP ZrO2 core material veneered with a compatible ceramic is an acceptable alternative in the fabrication of FPDs with the extensions investigated in this study. Special attention, however, must be paid to designing the core for an occlusal shape that provides sufficient support for the veneer.

A retrospective analysis of factors associated with multiple implant failures in maxillae.

This retrospective study was designed to verify the factors that influence implant failures. Six prosthodontic clinics in Sweden participated in the study, and together they included a total of 54 patients treated between January 1988 and December 1996. All patients were completely edentulous in the maxilla, and received either a fixed prosthesis or an overdenture supported by at least 4 implants (Brånemark System). Half of the patients belonged to the study group, and an inclusion criterion for this group was that they had lost at least half of their implants. To reduce bias, the patients in the control group were matched to the study group, i.e. they were selected so that both groups were as identical as possible. The results of the study indicate that the control group had a better initial bone support than the study group. Furthermore, the patients in the study group suffered from circumstances that could induce implant failure, such as bruxism, personal grief, depression, as well as addictions to cigarettes, alcohol and/or narcotics. On the study form the clinicians were asked to give their own opinion of the reason for implant failure. The answers given could easily be grouped into 5 different topics, and this experience can be useful to improve patient selection. This study suggests that there are certain factors of importance to consider to prevent a cluster phenomenon of implant failures i.e. lack of bone support, heavy smoking habits and bruxism.

Five-year evaluation of posterior all-ceramic three-unit (In-Ceram) FPDs.

PURPOSE: The purpose of this study was to investigate whether the properties of the In-Ceram material are adequate for use in posterior three-unit fixed partial dentures (FPD) and to evaluate the clinical method regarding preparation technique, design, and choice of cement. MATERIALS AND METHODS: Eighteen patients were treated with a total of 20 posterior three-unit FPDs according to the In-Ceram technique. The FPDs were constructed with bilateral support and one pontic and were all replacing one premolar or a molar (11 replacing premolars and 9 replacing molars). They were evaluated 6 months after delivery and then once yearly. RESULTS: Eighteen of the 20 FPDs (90%) showed no defects at any of the follow-up examinations and were functioning well after 5 years. No caries or signs of gingivitis or periodontitis exceeding those found in the rest of the dentition were registered. CONCLUSION: The In-Ceram technique is, in a 5-year perspective and adopted for three-unit FPDs, an acceptable treatment alternative. Further studies must, however, be performed before the material can be recommended for more extensive restorations than the FPDs included in this study.

An 8-year follow-up of removable partial denture treatment performed by the Public Dental Health Service in a Swedish county.

The aim of the present study was to evaluate clasp-retained removable partial dentures (RPDs) made in the Public Dental Health Service (PDHS) in Orebro County in 1989. Records from all 25 PDHS clinics concerning RPDs from 1989 were collected after eight years and available information was registered. The entire material consisted of 447 RPDs (both attachment-retained and clasp-retained RPDs) in 387 patients. Of the 316 clasp-retained RPDs that were traceable, 208 were followed from 1989 to 1997. In most instances, information on diagnoses, alternative treatments and design of the RPDs was lacking. One hundred and thirty-two (42%) of the 316 clasp-retained RPDs were judged to still be in use in 1997 while 75 were not in use. The main reason for ceased use was dislike by the patient. There were 108 clasp-retained RPDs that were not possible to follow from 1989 to 1997 because there were no notes regarding follow-ups in the records. The most common technical complications noted in the records during the observation period were clasp fractures and loosened artificial teeth.

Implant-supported fixed prostheses for the rehabilitation of periodontally compromised dentitions: a 3-year prospective clinical study.

BACKGROUND: The application of a strict hygiene maintenance care protocol following rehabilitation of periodontally compromised dentitions by means of tooth-supported fixed partial dentures has demonstrated excellent long-term treatment outcome. PURPOSE: A clinical and radiographic study was performed to document and evaluate the short- and medium-term result of occlusal rehabilitation by means of implant-supported fixed prostheses (ISFPs) in patients treated for advanced periodontal disease. MATERIALS AND METHODS: Forty-three consecutive patients were included. All patients were referred because of advanced periodontal disease. Before the implant therapy was initiated, periodontal treatment was performed and the outcome evaluated during at least a 6-month period. An individual maintenance care program was designed for each patient. All 125 implants were placed using a two-stage surgical approach. Following installation of the ISFPs, all patients underwent a baseline examination including evaluation of oral hygiene, periodontal or peri-implant conditions, and radiographs. These examinations were repeated annually during the 3-year observation period. RESULTS: No single implant was lost during the 3-year follow-up period. The percentages of plaque-harboring surfaces and bleeding units on probing were found to be low (< 10%), and no soft-tissue complications were recorded. The mean marginal bone resorption during the observation period amounted to 0.21 mm. In a few patients, apposition of marginal bone was observed. Bone loss amounting to 0.5 mm or less was found around 81% of the implants (101/125 implants). The amount of bone loss around the remaining 24 implants (19%) varied between 0.5 and 2.0 mm. CONCLUSIONS: The present clinical trial demonstrates that, at least during a 3-year period, the ISFP is an acceptable and predictable treatment option for rehabilitation in patients who have lost their teeth because of periodontal disease. This observation seems to be valid in edentulous and partially dentate jaws. A prerequisite to reach such a favorable treatment outcome is possibly the combination of the strict maintenance care program and the careful design of the ISFPs.

Fixed mandibular restorations on three early-loaded regular platform Brånemark implants.

BACKGROUND: Originally, the Brånemark System was used as a two-stage surgical procedure. Comparable clinical results have made one-stage and early-loading concepts possible alternatives in the edentulous mandible. From the patient's point of view, the financial aspect of implant treatment is important. In an attempt to decrease financial burden, the reduction of surgical interventions and reduction of the number of implants could be considered. PURPOSE: This prospective multicenter study evaluated (1) the 1- and 3-year success rates of implants loaded within 1 month after one-stage surgery with a fixed 10- to 12-unit bridge on three regular platform Brånemark System implants in the mandible, (2) the outcome of the prosthetic treatment, and (3) the opinion of patients regarding the treatment procedure. MATERIALS AND METHODS: Of 20 patients, 19 received five implants in the mandible, of which three were functionally loaded with the one-stage technique (group 1). The loaded implants were inserted in a tripodal position, one implant in the symphysis and two located anterior of the mental foramen in the bicuspid area. Two additional implants were inserted for safety reasons but were not intended to be included in the restoration. These two additional implants served as either an unloaded one-stage control implant (group 2) or an unloaded control implant installed with the submerged technique (group 3). Immediately after surgery, the implants were loaded with a relined denture. The patients received a 10- to 12-unit prosthetic reconstruction an average 31 days (range, 4-53 d) after surgery. Implant stability was clinically checked at 3, 12, and 36 months. Radiographs were taken at corresponding follow-up visits to calculate bone-to-implant level and marginal bone resorption. RESULTS: Six of 60 functionally loaded implants (10%) and 3 of 20 prostheses (15%) failed within the first year. The cumulative implant failure rate in group 1, both after 1 and after 3 years, was 9.5%. No implant failure occurred in the control groups 2 and 3. The average marginal bone level measured at 1 and 3 years was 1.6 mm (SD = 0.8 mm) and 2.1 mm (SD = 0.2 mm), respectively, for group 1; 1.5 mm (SD = 1.3 mm) and 2.4 mm (SD = 0.6 mm), respectively, for group 2; 0.8 mm (SD = 1.4 mm) and 0.7 mm (SD = 0.9 mm), respectively, for group 3. CONCLUSIONS: The results of treatment using three regular platform Brånemark System implants supporting a fixed mandibular arch reconstruction were less favorable than the outcome that can be expected with a standard four- to six-implant with one-stage surgery.

Immediate functional loading of Brånemark single tooth implants. An 18 months' clinical pilot follow-up study.

A clinical and radiographical study was performed to evaluate the treatment outcome of single tooth replacements with artificial crowns retained to implants installed according to a 1-stage surgical procedure and immediate loading (Experimental Group = EG) in comparison to the original 2-stage concept (Control Group = CG). The EG comprised 14 patients (= 14 implants) and the CG comprised 8 patients (= 8 implants), all with single tooth losses anterior to the molars. Beyond the non-smoking criterion the following criteria were adopted: i) the amount of bone had to allow for installation of a fixture with a minimum length of 13 mm and Ø = 3.75 mm, ii) the jaw relationship had to allow for bilateral occlusal stability, iii) the patients should be judged to be non-bruxers, and iv) the patients had to be available for the follow-up and maintenance programme. In the EG a temporary crown was connected to the implant within 24 h following fixture installation. Six months later this crown was replaced with a permanent one. In the CG the surgical and prosthetic treatment followed the standard protocol. Out of the 14 fixtures in the EG 2 were lost up to 5 months in function and were subsequently removed. All remaining 12 implants were stable at every subsequent follow-up examination. No fixture losses were recorded in the CG and all implants in this group were stable at the follow-ups. At the 6-month observation interval all the participating 20 patients were radiographically examined, an examination that was repeated at the 18-month follow-up. The analysis of the radiographs from the EG as well as from the CG disclosed that during the 12-month observation period the mean change of bone support was about 0.1 mm. Further studies, designed as controlled multicenter ones, have to be performed before the results of this pilot study can be recommended for more general use.

Social equality and dental conditions--a study of an adult population in Southern Sweden.

This study aimed to: describe dental conditions--focusing on prosthodontic variables--in relation to social conditions in the late 1990s in an adult population of Southern Sweden, evaluate if a change could be traced in the pattern of socioeconomic influences on dental conditions, and study if various attitudes toward dental care were associated with social as well as dental conditions. The study was based on questionnaire responses. Significant differences in dental conditions and denture prevalence were found for age and education. To a majority of the sample it was very important to have own teeth and/or fixed restorations and the opportunity to attend regular dental care. The cost for dental care was very important for 52% of the sample especially for men, those with low education, and those wearing removable denture. Need for dental care that could not be provided for because of the costs was experienced by 9%. Eighteen percent stated that they once or more had refrained from dental care because of the cost. Those with removable dentures and low education dominated. Besides socioeconomic differences in dental conditions, there were sociodental differences in attitudes concerning the importance of costs, self-estimated needs, and cost-barriers for dental care.

Fracture strength of In-Ceram all-ceramic bridges in relation to cervical shape and try-in procedure. An in-vitro study.

Investigations were performed on the strength of dental porcelain depending on whether it was exposed to saliva before or after the final firing. Forty porcelain specimens were fabricated and subjected to different treatments. A three-point flexural test was performed. In a second study investigations were performed to compare how the cervical shape of the preparation influenced the fracture strength of fixed partial dentures made of glass-infiltrated aluminium oxide. It was concluded that short-term exposure to saliva could have a negative effect on the strength of porcelain and that all-ceramic bridges luted with non-adhesive luting techniques should be supported by abutments with shoulder preparations.

Early functional loading of Brånemark dental implants: 5-year clinical follow-up study.

BACKGROUND: Short-term clinical studies have indicated the possibility of one-stage surgery and early loading of machined titanium implants. However, long-term data comparing the outcome to the conventional two-stage technique are missing. PURPOSE: A clinical and radiographic study was performed to compare the outcome of oral rehabilitation of the edentulous mandible by fixed suprastructures connected to implants installed according to either (1) a one-stage surgical procedure and early loading (experimental group--EG) or (2) the original two-stage concept (reference group--RG). The EG and RG comprised 16 and 11 subjects, respectively. MATERIALS AND METHODS: The following specific inclusion criterion were adopted: (1) all patients had to consider themselves to be in good general health, (2) the amount of bone had to enable the installation of five to six, at least 10-mm long fixtures (Mk II fixtures; Nobel Biocare AB, Göteborg, Sweden) between the mental foramina, and (3) the patients had to be available for the follow-up and maintenance program. A total of 88 implants were placed in the EG compared to 30 in the RG. In the EG, fixed appliances were connected to the implants within 20 days following implant installation while the fixed appliances in the RG were connected about 4 months following fixture installation. At delivery of the suprastructures, all patients were radiographically examined, an examination that was repeated at the 18- and 60-month follow-ups. RESULTS: The analysis of the radiographs from the EG disclosed that during the observation period, between 18 and 60 months, the mean loss of bone support amounted to 0.2 mm (SD = 0.4). The corresponding value observed in the RG was 0.0 mm (SD = 0.5). During the 60-month observation period, no fixture was lost in any of the two groups examined. The implants under study as well as those in the reference material were at all observation intervals found to be clinically stable. CONCLUSIONS: This clinical study demonstrated that it is, at least based on a 5-year observation period, possible to successfully load via a permanent fixed rigid cross-arch suprastructure titanium dental implants soon after installation. However, such a treatment approach has to be strictly limited to the interforamina area of the edentulous mandible. Furthermore, the bone resorption was found to be within the same range around such implants as around implants installed and loaded according to the original two-stage protocol.

Immediate functional loading of Brånemark dental implants. An 18-month clinical follow-up study.

A clinical and radiographical study was performed to compare the outcome of oral rehabilitation in the edentulous mandible by fixed supraconstructions connected to implants installed according to either i) a 1-stage surgical procedure and immediate loading (Experimental Group-EG), or ii) the original 2-stage concept (Reference Group-RG). The EG comprised 16 subjects with edentulous mandibles. Beyond the non-smoking criteria the following specific inclusion criteria were adopted: i) all patients had to consider themselves to be in good general health, ii) the amount of bone had to enable the installation of 5-6, at least 10 mm long fixtures to be bicortically anchored (Mk II fixtures; Nobel Biocare AB, Göteborg, Sweden) between the mental foramina, and iii) the patients had to be available for the follow-up and maintenance programme. A total of 88 implants were placed in the EG (16 patients) compared to 30 in the RG (11 patients). In the EG, fixed appliances were connected to the implants within 20 days following implant installation while the fixed appliances in the RG were connected about 4 months following fixture installation. At the time for delivery of the supraconstructions all 27 patients were radiographically examined, an examination that was repeated at the 18-month follow-up. The analysis of the radiographs from the EG disclosed that during the 18-month observation period the mean loss of bone support amounted to 0.4 mm. The corresponding value observed in the RG was 0.8 mm. During the 18-month observation period no fixture was lost in any of the 2 groups examined. The implants under study as well as those in the reference material were at all observation intervals found to be clinically stable. The present clinical study demonstrated that it is, at least based on an 18-month observation period, possible to successfully load titanium dental implants immediately following installation via a permanent fixed rigid cross-arch supraconstruction. However, such a treatment approach has so far to be strictly limited to the inter-foramina area of the edentulous mandible.

A six-year follow-up study of maxillary overdentures on osseointegrated implants.

This study comprised a clinical and radiological examination of two groups of 14 patients receiving overdentures of the same design on osseointegrated implants. The mean follow-up period was 82 months and 35 months in the two groups the fixture success rate was 84% and 85% and the marginal bone loss 0.97 mm and 1.29 mm respectively. The follow-up of the two groups was guided by several clinical parameters and apart from the loss of fixtures and adjustments of the attachment system only a few complications were registered. The results show that this treatment method is a successful alternative in the treatment of the edentulous maxillae.

Overdentures--when and how.

Implant borne overdentures are a reliable and simple solution to denture retention and stability problems. Such a treatment option requires careful planning and the basis for this is made from the results of clinical trials. An overdenture symposium on this subject was held at Naantali, Finland on 26th August, 1994. The following paper is a summary of the proceedings.