Search

This pilot study aimed to explore whether occlusal contacts during lateral excursions are influenced by tilted body positions. Occlusal contacts in lateral excursions were verified for 30 dental students and 22 dental staff members using articulation foil while patients were seated in a dental chair. The number and location of dynamic tooth contacts (initial and halfway) were registered with the back of the dental chair in three positions: upright, 45 degrees, and supine. For the majority of subjects (96%), dynamic occlusal contacts changed when the body position was altered. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate data on the prevalence of tooth wear in adults and assess possible correlations using a systematic review. Materials and Methods: A search of the literature, using PubMed and the Cochrane Library, from January 1980 to July 2007 was made using keywords 'tooth + wear'; 'dental + attrition + prevalence', 'dental + wear + prevalence', 'erosion + prevalence'; and 'abrasion + prevalence.' References were independently screened for inclusion and exclusion by two investigators and Cohen Kappa was used as the measure of agreement. Data were collected and converted into the Smith and Knight Tooth Wear Index. Results: One hundred eighty-six references were initially selected and subjected to the systematic review procedure; 13 survived the inclusion procedure. Four articles were suitable for regression analysis at tooth level (R2 = .593) and 3 at subject level (R2 = .736), using 'age and age squared' and 'age squared' as variables, respectively. Six studies reported males having significantly more tooth wear than females. Conclusion: The predicted percentage of adults presenting with severe tooth wear increases from 3% at the age of 20 years to 17% at the age of 70 years Increasing levels of tooth wear are significantly associated with age. [ABSTRACT FROM AUTHOR]

PURPOSE: To assess esthetic perceptions among Tanzanian adults regarding missing teeth using a cross-sectional clinical study of a convenience sample of 5,532 subjects in the Northern coastal zone of Tanzania. MATERIALS AND METHODS: The dental status of urban and rural Tanzanian adults (5,532 subjects, ages between 20 and 80 years) was recorded. A structured interview was used to assess esthetic perception (yes/no complaint) considering the location and number of missing teeth. Logistic regression analysis was applied to determine the effects of the variables age (2 groups: < or = 45 years vs > 45 years), gender, socioeconomic status (high/middle vs low), and residence (urban vs rural) on the number of complaints. RESULTS: Of the subjects with 1 or more missing maxillary anterior teeth, 54% reported a complaint. Dissatisfaction was reported by significantly more subjects < or = 45 years of age and subjects with high/middle socioeconomic status. Gender and residence had no significant influence. Of the subjects with missing maxillary premolar(s) (no missing anterior teeth), 25% reported esthetic complaints (missing first premolar: 24%; missing second premolar: 11%; missing first and second premolar on the same side: 44%). Dissatisfaction was significantly greater in women, subjects < or = 45 years of age, and subjects with high/middle socioeconomic status. Residence had no significant influence. Fewer than 1% of the subjects were dissatisfied with missing maxillary molars. CONCLUSION: Among this group of Tanzanian adults, absence of teeth played a considerable role in the esthetic appreciation of their dentition. Complaints were associated with both number and location of missing teeth. [ABSTRACT FROM AUTHOR]

PURPOSE: The aim of this long-term follow-up study was to collect up to 17 years of survival data of endodontically treated single teeth with or without a prefabricated metal post. MATERIALS AND METHODS: Single teeth were provided with direct composite resin core-crown reconstructions with or without posts by 15 operators. Restorations consisted of either a prefabricated metal post and a composite core-crown reconstruction or a post-free direct composite reconstruction. Allocation of either restoration was performed by balanced drawing. These restorations were not covered by an artificial crown. The study sample consisted of 87 patients who received 98 core-crown reconstructions. The performance of the restorations was evaluated based on data collected from the files of the clinicians currently monitoring the oral health of the patients. The survival probability was analyzed at different levels: on the restoration level and on the level of the tooth carrying the restoration. Kaplan-Meier analysis was used to compare survival probabilities. RESULTS: Post placement showed no influence on the survival probability at either level (P > .05). The estimated overall survival rate at 17 years was 53% +/- 14% at the restoration level and 79% +/- 11% at the tooth level. CONCLUSION: The results of this long-term follow-up study showed no difference in survival probabilities between different direct composite resin core-crown reconstructions of endodontically treated single teeth (with or without a post). [ABSTRACT FROM AUTHOR]

PURPOSE: To assess oral health and prosthodontic conditions of Chinese adults and the changes in these conditions over time. MATERIALS AND METHODS: PubMed was searched by combining the keyword China with dental health survey, oral health, tooth loss, DMFT (decayed/missing/filled teeth), dental prosthesis, or dentures. After selection, 12 studies remained. Data were obtained from these studies on DMFT, DMFT components, and teeth present and were tested against the following independent variables using analysis of variance: age, residence, and year of data collection. RESULTS: DMFT increased with age (P = .0001). Rural subjects presented higher DMFT based on the higher 'decayed' component (P = .003), which increased markedly for subjects over 45 years of age. The number of teeth present decreased with increasing age (P = .0002). The results showed that Chinese subjects who are 65 years old have an average of 20 teeth. Urban subjects had more teeth present (P= .05), although no difference was seen for the 'missing' component of DMFT. In general, few prosthodontic data could be extracted from the selected studies, and these data were often unspecific or inconclusive. CONCLUSIONS: The 'filled' component of DMFT remained consistently low for all ages, indicating limited care. All outcomes were independent from year of data collection, indicating unchanged care. Outcome aggregation on the number of functional teeth and prosthetic care was impossible. For future reports, it is recommended to include additional information about location and function (in terms of occluding pairs) of teeth present when describing oral health status. [ABSTRACT FROM AUTHOR]

PURPOSE: This study aimed to assess the efficacy and short-term effectiveness of the morphology and function of direct and indirect cusp-replacing resin composite restorations. MATERIALS AND METHODS: In 94 patients, 106 cusp-replacing restorations for maxillary premolars were fabricated to restore Class II caries lesions with 1 cusp missing. Fifty-four direct (Clearfil AP-X) and 52 indirect (Estenia) resin composite restorations were placed following a strict protocol. The treatment technique and operator were assigned randomly. Treatment time was recorded for all restorations. One-month postoperative evaluation included assessment of postoperative sensitivity and presence of occlusal and proximal contacts. RESULTS: Treatment time for the indirect technique (68 +/- 17 min) was longer than for the direct technique (45 +/- 13 min). Regression analysis revealed that the restorative method, operator, and location of the preparation outline had a statistically significant effect on the total treatment time. Occlusal contacts were observed in 94% of the direct restorations and in 98% of the indirect restorations (chi-square, P>.05). Mesial proximal contacts were present in 98% of the direct and in 97% of the indirect restorations (chi-square, P > .05). Distal contacts were present in 100% of the restorations for both techniques. Postoperative sensitivity within 1 week posttreatment was reported for 11% of the direct restorations and for 13% of the indirect restorations, but decreased to 4% and 6%, respectively, after 1 month (chi-square, P > .05). CONCLUSION: The results of this study suggest that in the short term, both direct and indirect adhesive techniques are adequate to restore the morphology and function of premolars presenting with Class II caries lesions and a missing cusp. [ABSTRACT FROM AUTHOR]

PURPOSE: This study investigated the prevalence of signs and symptoms associated with temporomandibular disorders (TMD) in adults with shortened dental arches in Tanzania. MATERIALS AND METHODS: The shortened dental arch group comprised 725 subjects with an intact anterior region and zero to eight occluding pairs of teeth posteriorly. They were categorized into five groups according to length and symmetry of the dental arches. A control group of 125 subjects with complete dental arches was included. The subjects were interviewed with questions related to pain and sounds within the temporomandibular joints and restricted mobility of the mandible. Clinical examination consisted of registration of clicking or crepitation of the joints, measuring maximum mouth opening, and assessing occlusal tooth wear. RESULTS: Joint sounds were reported significantly more frequently by subjects with posterior support only unilaterally (17%) and by subjects with no posterior support (10%) compared to other categories of dental arches (3% to 5%). No significant differences were found between categories of dental arches with respect to pain (2% to 9%), restricted mobility of the mandible (0% to 1%), maximum mouth opening < 40 mm (0% to 3%), or clicking or crepitation of the joints (12% to 23%). For the younger age group (> or = 20 and < 40 years), tooth wear occurred significantly more often in subjects with no posterior support. For the older age group (> or = 40 years), tooth wear increased significantly with decrease of posterior support. CONCLUSION: No evidence was found that shortened dental arches provoke signs and symptoms associated with TMD. However, when all posterior support is unilaterally or bilaterally absent, the risk for pain and joint sounds seems to increase. [ABSTRACT FROM AUTHOR]

Objectives: The purpose of this clinical study was to evaluate the long-term outcome of 3-unit anterior fixed partial dentures (FPDs) made of fiber-reinforced resin composite (FRC), and to identify design factors influencing the survival rate. Methods: 52 patients (26 females, 26 males) received 60 indirectly made FRC FPDs, using pre-impregnated unidirectional glass fibers, requiring manual wetting, as framework material. FPDs were surface (n=48) or hybrid (n=12) retained and mainly located in the upper jaw. Hybrid FPDs had a combination of retainers; i.e. crown at one and surface retention at the other abutment tooth. Surface FPDs were either purely adhesively retained (n=29) or with additional mechanical retention (n=19). Follow-up period was at minimum 5 years, with check-ups every 1-2 years. Six operators were involved, in three centers in the Netherlands, Finland and Sweden. Survival rates, including repairable defects of FPDs, and success rates were determined. Results: Kaplan-Meier survival rate at 5 years was 64% (SE 7%). For the level of success, values were 45% (SE 7%) and the estimated median survival time 58 (SE 10.1) months. For surface FPDs, additional mechanical retention did not improve survival significantly. There was a trend towards better survival of surface FPDs over hybrid FPDs, but differences were not significant. Main failure modes were fracture of the FPD and delamination of veneering composite. Significance: A success rate of 45% and a survival rate of 64% after 5 years was found. Fracture of the framework and delamination are the most prevalent failure modes, especially for surface FPDs. [ABSTRACT FROM AUTHOR]

On the basis of a case, this study considers which prosthetic device is suitable as a replacement for a first molar. At the request of the patient, the least invasive option was sought. The outcome in this case was that the adhesive bridge with abutment teeth with class-2 restorations might be suitable. Of the 3 types of adhesive bridges (metal-porcelain, fibre-reinforced composite and ceramic), most experience has been acquired with the 3-piece metal-porcelain adhesive bridge. Several studies assessing the clinical behaviour of this type are available. Its lifespan is rather comparable to that of the conventional bridge on crowns, provided strategic preparation is carried out with grooves and supports to promote resistance. If the palatal or lingual surface consists entirely of enamel for bonding, it does not seem to be a problem for the wing of the bridge to be additionally bonded approximally to a composite restoration if present in the abutment tooth.

In essence the resin-bonded fixed partial denture, or resin-bonded bridge, is an artificial tooth that is bonded to 1 or 2 abutment teeth. If the resin-bonded bridge is directly made with resin composite intra-orally, then the connector area is the weakest link. The alternative is to produce an indirect resin-bonded bridge in which a metal or ceramic frame spans the space between the abutments. The bridge is bonded to the abutments with composite. The moderate clinical results of the resin-bonded bridge can be associated with a deficiency of the abutment teeth preparation. Therefore, strategic preparation with grooves and rests is of substantial importance for proper support. By doing so, the longevity of the straightforward resin-bonded bridge rivals the performance of other dental provisions. There is a disagreement whether 2-unit resin-bonded bridges perform better than their 3-unit counterparts. Two optimally prepared abutment teeth are still a solid basis for a metal-ceramic resin-bonded bridge. For ceramic resin-bonded bridges, 1 abutment seems to be sufficient.

The purpose of root canal posts is to obtain additional retention for build-up restorations of endodontically treated teeth so they can be functionally reconstructed. Due to developments in adhesive dentistry and a lack of clinical evidence, root canal posts are used less and less. Currently, the advice of the European Society of Endodontology is to use a root canal post only in front teeth and premolars in the absence of remaining coronal dentine walls. It is important to avoid additional preparation when placing a root canal post, because this causes (additional) weakness of the tooth. The loss of dental tissue due to preparation cannot be compensated for by placing a post.

Background: Evaluation of a new vertical dimension of occlusion (VDO) in complex restorative treatments is considered a necessary step prior to placement of restorations., Objectives: This randomised controlled trial (RCT) aimed to assess the effects of using an evaluation of a VDO increase before restorative treatment in patients with moderate-to-severe tooth wear, on OHRQoL, freeway space (FWS) and interventions to restorations., Methods: Forty-two patients with tooth wear were included and randomly allocated to either a test phase with a Removable Appliance (RA) or no test phase. Restorative treatment consisted of restoration of all teeth using composite restorations in an increased VDO. OHIP-score, freeway space (FWS) and clinical acceptability of restorations were assessed at baseline and at recall appointments (1 month and 1 year). Intervention to restoration was scored in case of material chipping or when the abutment tooth had increased sensitivity that could be linked to occlusal overloading. ANCOVA analyses, Univariate Cox regression, t-tests and descriptive analyses were performed (p < .05)., Results: Clinical follow-up after 1 year was completed for 41 patients. No significant effect of testing the VDO with a RA could be found on the OHIP-score (p = .14). Reduction of FWS in the RA group, compared to the control group, was significantly lower at 1 year (p = .01, 95% CI -1.09 to -0.15). No effect on early interventions to restorations was found (p = .94)., Conclusion: This RCT showed that a removable appliance is not indicated to functionally test the increased VDO prior to restorative treatment in patients with tooth wear., (© 2023 The Authors. Journal of Oral Rehabilitation published by John Wiley & Sons Ltd.)

Objectives: The objective is to evaluate the long-term clinical survival and performance of direct and indirect resin composite restorations replacing cusps in vital upper premolars., Methods: Between 2001 and 2007, 176 upper premolars in 157 patients were restored with 92 direct and 84 indirect resin composite restorations as part of an RCT. Inclusion criteria were fracture of the buccal or palatal cusp of vital upper premolars along with a class II cavity or restoration in the same tooth., Results: Forty patients having 23 direct and 22 indirect composite restorations respectively, were lost to follow-up (25.6%). The cumulative Kaplan-Meier survival rates were 63.6% (mean observation time: 15.3 years, SE 5.6%) with an AFR of 2.4% for direct restorations and 54.5% (mean observation time: 13.9 years, SE: 6.4%) with an AFR of 3.3% for indirect restorations. The Cox regression analysis revealed a statistically significant influence of the patient's age at placement on the survival of the restoration (HR 1.036, p = 0.024), the variables gender, type of upper premolar, type of restoration, and which cusp involved in the restoration had no statistically significant influence. Direct composite restorations failed predominantly due to tooth fracture, indirect restorations primarily by adhesive failure (p < 0.05)., Significance: There was no statistically significant difference in survival rates between direct and indirect composite cusp-replacing restorations. Both direct and indirect resin composite cusp-replacing restorations are suitable options to restore compromised premolars. The longer treatment time and higher costs for the indirect restoration argue in favor of the direct technique., Competing Interests: Declaration of Competing Interest All authors declare that they have no conflicts of interest., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: To describe the digital workflow applied for restoring a severely worn dentition with minimally invasive CAD/CAM resin nano-composite restorations., Materials and Methods: A 40-year-old male in good general health and with full-arch dentition suffered from dentin hypersensitivity and wanted to improve the esthetics of his worn anterior teeth. The dental wear can be described as general, grade 3, according to the Tooth Wear Index,27 with more wear in maxillary than in mandibular teeth. Signs and symptoms were typical for a chemical type of wear, with some mechanical wear also apparent. No functional problems, eg, impaired chewing, were present. On the OHIP-49 questionnaire, the patient expressed a reduced quality of life. The goal of the treatment was to reconstruct the anatomical form of the teeth as far as possible, thereby also improving quality of life. Due to the rather large volume of lost tooth tissue per tooth, indirect treatment using CAD/CAM resin nano-composite restorations (LAVA Ultimate, 3M Oral Care) was applied., Results: The seating of the CAD/CAM resin nano-composite restorations (LAVA Ultimate, 3M Oral Care) restorations was considered precise., Conclusion: In the treatment of severe tooth wear, the described digital workflow using CAD/CAM restorations for occluding restorations and direct composite materials in the esthetic zone is a potential treatment modality that is workable and minimally invasive.

Purpose: The aim of this prospective study was to evaluate the clinical performance of minimally invasive, CAD/CAM nano-ceramic (composite) restorations in patients with severe tooth wear, the effect of the restorative treatment on the oral health-related quality of life (OHRQoL), and the etiology of tooth wear as a risk factor for restoration failure., Materials and Methods: Patients with generalized severe tooth wear were included. Restorations (LAVA Ultimate, 3M Oral Care) were cemented (RelyX Ultimate, 3M Oral Care) on all teeth and were evaluated after 1 month and 1 year. OHRQoL was assessed via questionnaires at baseline and after 1 year. Differences were evaluated (paired t-test). Two mechanical tooth-wear lesions resulting from tooth-tooth contact, and 3 chemical tooth wear lesions resulting from intrinsic or extrinsic acids dissolving natural hard tooth substance, were evaluated to assess the etiology of tooth wear in association with restoration failure using multilevel logistic regression analyses (p < 0.05)., Results: Twenty-one patients (age: 41.7 ± 10.4 years) were evaluated after 1 year (13.5 ± 1.2 months). 568 indirect CAD/CAM restorations were placed. None were replaced or lost. Twelve were repaired and 10 were refurbished. Success rates were 100% to 97.2%. Questionnaires showed a significant positive impact of the treatment on OHRQoL (p < 0.001). The presence of mechanical lesions did not pose a higher risk for restoration failure (p = 0.78). The presence of chemical lesions showed a lower risk of restoration failure (p = 0.002)., Conclusion: The use of minimally invasive, CAD/CAM nano-ceramic (composite) restorations in the restorative treatment of severely worn dentitions showed satisfactory results in the short term.

Objective: The study aimed to evaluate survival and failure behavior of Direct Composite Restorations (DRC) and Indirect Composite Restorations (ICR) on molars and anterior teeth, in a Randomized Controlled Trial (RCT)., Methods: Patients with generalized severe tooth wear were included, and randomly assigned to one of 2 protocols: (1) DCR: All teeth were restored with directly applied micro-hybrid composite restorations (Clearfil AP-X, Kuraray) for load bearing areas and nano-hybrid composite restorations (IPS Empress Direct, Ivoclar Vivadent) for buccal veneers; (2) ICR: First molars were restored with indirect composite 'tabletop' restorations and maxillary anterior teeth were restored with indirect palatal veneer restorations (Clearfil Estenia C&B, cemented with Panavia F, Kuraray). Remaining teeth were restored directly. Restorations were evaluated after 3 years, focusing on clinical acceptability. Statistical analysis was performed using Kaplan Meier curves, Annual Failure Rates (AFRs), and univariate Cox regression analyses (p < 0.05)., Results: 41 patients (age: 36.6 ± 6.6y) were evaluated after 3 years (40.0 ± 2.2 m). 408 restorations on first molars and palatal veneers on maxillary anterior teeth were part of this RCT, with 220 DCRs and 188 ICRs. No differences in survival between treatment modality for palatal veneers for any failure criteria were found. Tabletop restorations on first molars showed a considerable higher failure rate for ICR compared to DCR (p = 0.026, HR: 3.37, 95%CI = 1.16-9.81)., Significance: In this RCT, directly applied composite restorations showed superior behavior compared to the indirect composite restorations, when used in the molar region., (Copyright © 2021 The Author(s). Published by Elsevier Inc. All rights reserved.)

Objectives: To evaluate the mid-term clinical performance of direct composite restorations placed in patients with pathological tooth wear needing full rehabilitation with an increase of vertical dimension of occlusion., Methods: In a prospective trial 34 patients (34.0 ± 8.4 years; 25 males, 9 females) were treated with a minimal invasive additive technique using composite restorations. The restorative treatment protocol was to provide all teeth with composite build-up restorations in an increased vertical dimension of occlusion (VDO) using the DSO-technique. Recall appointments were planned after 1 month, 1 and 3 years after treatment. Restorations were scored for clinically acceptability (FDI-criteria) and scores 4 and 5 were recorded as clinically unacceptable. Frequencies of failures and Kaplan Meier survival curves are presented and effect of relevant variables was calculated with a multifactorial Cox regression (p < 0.05)., Results: 1256 Restorations were placed, 687 anterior, 324 premolar, and 245 molar restorations. After a mean observation time of 39.7 months a total of 69 failures were observed, of which 61 restorations were repaired (score 4) and 8 were replaced (score 5). Most common reasons for failure were (chip) fractures (n = 43) and caries (n = 11). Placement of anterior restorations in two sessions led to significant 4.6 times more failures then placed in one session., Conclusions: In patients with severe tooth wear a full rehabilitation, in an increased vertical dimension of occlusion, direct composite resin restorations show a 94.8% success and 99.3% survival rate after a period of 3.5 years., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objectives: This randomized clinical trial compared the survival of composite resin restorations and metal-ceramic crowns on endodontically treated teeth that received a glass fiber post using 2 different cementation methods., Methods: Forty-seven patients (age 42.5 ± 11.5) with fifty-seven endodontically treated teeth with extensive coronal damage but always with one intact surface were randomly allocated according to the type of coronal restoration: metal-ceramic crown or composite resin. In case of crown restoration, a core buildup was performed with microhybrid composite resin. The dentin bonding agent and composite resin used were the same for both direct and indirect restorations. Descriptive analysis was performed using FDI clinical criteria and survival of restorations/teeth analyzed using Kaplan-Meier statistics and log-rank tests., Results: 57 restorations (30 composite resin and 27 crowns) were made in 47 patients. The recall rate was 100% and follow up time ranged between 1 and 5 years. One tooth was extracted 11 months post-restoration due to root fracture (composite group). Eight composite restorations and one crown had reparable failures, all due to secondary caries or restoration fracture. The overall annual failure rate (AFR) was 0.92% after 50 months for success of the restorations, with 1.83% for the composite group and 0.26% for the metal-ceramic crown group. The log-rank test showed no difference for survival according to the type of restoration (p=0.344). However, for success rates, metal-ceramic crowns demonstrated better performance (p=0.022)., Conclusions: Indirect restorations provided higher acceptable clinical performance and lower need for re-intervention, but both types of restorations presented good survival rates. (NCT01461239)., Clinical Significance: When endodontically treated teeth with at least one intact surface must be restored, composite resin restorations and metal-ceramic crows are acceptable alternatives to achieve good survival and success rates., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The diagnostic use of oral radiology is an essential part of daily dental practice. Due to the potentially harmful nature of ionising radiation, the clinical use of oral radiology in the Netherlands is framed by clinical practice guidelines and regulatory requirements. Undergraduate students receive intensive theoretical and practical training in practical and theoretical radiology, with the aim of obtaining the 'Eindtermen Stralingshygiëne voor Tandartsen en Orthodontisten'-certificate, which is required for legal permission to use oral radiology in dental practice. It is recommended that the curriculum be expanded to include the areas of knowledge required to qualify for the 'Eindtermen Stralingshygiëne voor het gebruik van CBCT-toestellen door tandartsen' (the certificate for the use of conebeam radiology by dentists). The general dental practitioner is faced with changing laws and regulations in all areas of practice. One of the most significant legal changes in the field of dental radiology was the introduction of the new radiation protection and safety rules in 2014. Moreover, a large group of dentists is also being confronted with the transition from conventional to digital images, with all its challenges and changes in everyday practice.

The aim of the present study was to investigate the success and survival of restored endodontically treated teeth (ETT) in a general practice environment related to periodontal parameters. Data from 360 restored ETT treated between 2000 and 2011 were collected. Dates of interventions like restorations, repairs, replacements and extractions were recorded. Additionally, general information about patients and dentitions as well as periodontal status was recorded. Success was analyzed using Kaplan-Meier statistics and a multivariate Cox regression analysis was performed to assess variables influencing success and survival. After a mean observation time of 4.34 years (range 0.6 - 11.6 years), 19 teeth were extracted and 27 restorations needed repair or replacement. According to the Cox regression, increasing maximum pocket depth of the tooth resulted in a higher risk for failure (p=0.012). In conclusion, periodontal pocket depth was found to be a significant factor in the survival of restored ETT.

Objective: To study progression of tooth wear quantitatively in a convenient sample of young adults and to assess possible correlations with occlusal conditions., Methods: Twenty-eight dental students participated in a three-year follow up study on tooth wear. Visible wear facets on full arch gypsum casts were assessed using a flatbed scanner and measuring software. Regression analyses were used to assess possible associations between the registered occlusal conditions 'occlusal guidance scheme', 'vertical overbite', 'horizontal overbite', 'depth of sagittal curve', 'canine Angle class relation', 'history of orthodontic treatment', and 'self-reported grinding/clenching' (independent variables) and increase of wear facets (dependent variable)., Results: Mean increase in facet surface areas ranged from 1.2 mm2 (premolars, incisors) to 3.4 mm2 (molars); the relative increase ranged from 15% to 23%. Backward regression analysis showed no significant relation for 'group function', 'vertical overbite', 'depth of sagittal curve', 'history of orthodontic treatment' nor 'self-reported clenching. The final multiple linear regression model showed significant associations amongst 'anterior protected articulation' and 'horizontal overbite' and increase of facet surface areas. For all teeth combined, only 'anterior protected articulation' had a significant effect. 'Self reported grinding' did not have a significant effect (p>0.07)., Conclusions: In this study 'anterior protected articulation' and 'horizontal overbite', were significantly associated with the progression of tooth wear. Self reported grinding was not significantly associated with progression of tooth wear., Clinical Significance: Occlusal conditions such as anterior protected articulation and horizontal overbite seem to have an effect on the progression of occlusal tooth wear in this convenient sample of young adults., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

For the manufacture of single- and multi-unit fixed dental prostheses, effective communication between dentist and dental technician is required. Mutual insight concerning the (im)possibilities of available treatments and technical options is prerequisitefor this communication. The manufacture of single- and multi-unit fixed dental prostheses involves 4 phases: recording the required detailed information on the relevant teeth and the occlusal system, the technical adjustments, the technical design and the technical fabrication. These phases can be accomplished through an analogue or (semi)digital procedure. Pioneering developments are computer aided design and computer aided manufacturing (CAD/CAM), and computerised milling machines. Associated with this are 3 manufacturing methods which can be distinguished: the dental practice method, the dental laboratory method and the milling centre method. Materials applied are metal alloys and ceramics, while resins are used for provisional and transitional constructions. Due to the fact that the choice of material in the analogue procedure is limited, CAD/CAM offers more options, the digital procedure is expected to gain ground gradually. It is expected that this development will provide an impulse to higher quality.

The objective of this randomized control trial was to compare the five-year clinical performance of direct and indirect resin composite restorations replacing cusps. In 157 patients, 176 restorations were made to restore maxillary premolars with Class II cavities and one missing cusp. Ninety-two direct and 84 indirect resin composite restorations were placed by two operators, following a strict protocol. Treatment technique and operator were assigned randomly. Follow-up period was at least 4.5 yrs. Survival rates were determined with time to reparable failure and complete failure as endpoints. Kaplan-Meier five-year survival rates were 86.6% (SE 0.27%) for reparable failure and 87.2% (SE 0.27%) for complete failure. Differences between survival rates of direct and indirect restorations [89.9% (SE 0.34%) vs. 83.2% (SE 0.42%) for reparable failure and 91.2% (SE 0.32%) vs. 83.2% (SE 0.42%) for complete failure] were not statistically significant (p = .23 for reparable failure; p = .15 for complete failure). Mode of failure was predominantly adhesive. The results suggest that direct and indirect techniques provide comparable results over the long term (trial registration number: ISRCTN29200848).

In a correctly functioning occlusal system, the design of the occlusal parts of single-unit and multi-unit fixed dental prostheses is generally determined by the maximum intercuspation. Determining and recording the maxillomandibular relationships is only required in case the adjacent teeth do not offer adequate support or reference to put the maxillary and mandibular cast in maximum intercuspation or in case the existing occlusion needs a well-structured alteration. The maxillomandibular relationships can be determined and registered analogously and digitally and on that basis the maxillary and mandibular casts can be mounted in a (virtual) occludator or articulator. In the absence of a distinct occlusal plane, one may consider first carrying out a facebow recording and transfer. Usually, the accuracy of determining and recording the maxillomandibular relationships does not increase when using more complicated methods.

A single- or multi-unit fixed dental prosthesis can be attached to the abutment teeth through mechanical retention and gap sealing or by adhesion. For sealing the gap, water-soluble cements are appropriate, such as zinc phosphate, polycarboxylate, and (resin-modified) glasionomer cement. Attachment through adhesion can be performed with composite cement. If the hard tooth tissue is prepared adequately, composite cement provides sufficient adhesion, but self-adhesive composite cement is now also available. For the adhesion of the composite cement to the restorative materials of the single- or multi-unit fixed dental prosthesis, surface sandblasting, silanizing, and tin coating and the application of a metal primer or chemically active composite are available. Cementing a single- or multi-unit dental prosthesis involves 3 phases: 1. Cleansing the single- or multi-unit dental prosthesis and the abutment tooth/teeth; 2. Preparing the hard tooth tissue, mixing the cement and placing the single- or multi-unit dental prosthesis; 3. Removing the excess cement.

To manufacture single-unit and multi-unit fixed dental prostheses, an accurate cast is required. Casts can be obtained either by the conventional or the digital impression method. For both methods, dry tooth surfaces and a well exposed finish line of the tooth preparation are required. The conventional impression method requires an elastic impression material. Elastomers have a high detail accuracy, which can produce, in combination with a good fitting and rigid impression tray, an impression with reliable dimensional stability. Based on the number of different impression material consistencies used and the number ofphases of the impression procedure, several options of the conventional impression method can be distinguished. For the digital impression method, teeth or implants are scanned to produce a digital cast which can be used directly with the help of computer technology to produce single-unit or multi-unit fixed dental prostheses. The digital impression method has a number of advantages when compared to the conventional impression method, but is not applicable for all prosthetic cases.

Occlusal surfaces of teeth and restorations wear by repeated antagonistic contact. Two-body wear is the result of direct contact between occlusal surfaces. In cases of three-body wear, food is found between antagonistic teeth. Contact wear is expressed predominantly by abrasion and material fatigue. Erosion is a type of wear which does not involve direct antagonistic contact. Qualitative methods exist for registering occlusal tooth wear. Wear of restorations can be measured using casts. An obvious method for comparing rates of wear of restorative materials is laboratory research. This method has demonstrated that the wear rates of composite and enamel are similar. Cast metals and in particular ceramic wear less than enamel. The relation between oral factors and the rate of tooth wear is not always clear. Wellpolished surfaces of restorations wear less quickly and have less effect on the wearing of antagonistic teeth than rougher restoration surfaces.

After (extensive) loss of tooth tissue, vital teeth can be built up completely with composite restoration material. Sometimes, the application of additional retentive preparations is indicated. In exceptional cases, a root canal treatment is indicated, following which a root canal post is applied if necessary. Endodontically treated multi-rooted teeth can be built up entirely with composite, utilizing the pulp chamber and root canal accesses for retention. However, in single-rooted teeth a root canal post is necessary, in which case a prefabricated root post is used. Traditionally, metal posts were used in combination with a cast, indirect build-up restoration. Subsequently, directly fabricated cores, combining metal posts with amalgam or, at the present time, composite restoration material, became customary. The present trend is to use prefabricated or individually fabricated fibre-reinforced posts. After restoring a tooth with a build-up restoration, a combined build-up restoration can be chosen, or a direct or indirect crown single tooth prosthesis.

A resin-bonded fixed partial denture is a prosthetic construction which can replace I or several teeth in an occlusal system and which comprises a pontic element which is adhesively attached to 1 or more abutment teeth. To compensate for the limited shear strength of the adhesive layer, the Jixed partial denture is occlusally supported by the abutment(s). A direct resin-bonded fixed partial denture is made of composite, reinforced or not by a frame of flexible metal or fiber material. For an indirect resin-bonded fixed partial denture, a metal, fibre-reinforced composite or ceramic substructure is fabricated in a dental laboratory. The basic principle of a resin-bonded fixed partial denture is minimal invasiveness. However, a restoration in an abutment tooth requires a certain occlusal space which is realized by tooth preparation. Resistance preparations may be performed to improve the longevity of resin-bonded fixed partial dentures. Both financially and biologically, a resin-bonded bridge is a cost-effective prosthetic construction. The longevity is limited, but when the construction fails the negative consequences for the abutments are generally limited, which leaves open several types of other treatments.

Purpose: To assess whether dentin pins increase shear resistance of extensive composite restorations and to compare performance of mini fiber-reinforced composite (FRC) anchors with metal dentin pins in the laboratory., Methods: 30 extracted sound molars were randomly divided into three groups. Occlusal surfaces were ground flat with a standard surface area and resin composite restorations were made in Group A. In Groups B and C similar restorations were made, with additionally four metal pins placed in Group B and four FRC pins in Group C. Specimens were statically loaded until failure occurred. Failure modes were characterized as intact remaining tooth substrate (adhesive or cohesive failure of restoration) or fractured remaining tooth substrate., Results: Mean failure stresses were 6.5 MPa (SD 3.2 MPa) for Group A, 9.7 MPa (SD 2.6 MPa) for Group B and 9.2 MPa (SD 2.6 MPa) for Group C. Difference in mean failure stresses between Group A and Groups B and C was statistically significant (P = 0.01), while the difference between Groups B and C was not (P = 0.63). Failures of the restoration without fracture of tooth substrate were seen for 80% of specimens in Group A and 20% in Groups B and C (P = 0.04).

Objectives: To quantify swallowing threshold parameters of subjects with a moderate shortened dental arch dentition (SDA: missing molar teeth, but premolar teeth in occluding position and uninterrupted anterior regions) compared to subjects with a complete dental arch dentition (CDA)., Methods: Fourteen females with SDA (3-4 occlusal premolar units) and 14 females with CDA were instructed to chew silicone test 'food' (cubic particles with a total volume of 3 cm(3)). They spit it out the moment they felt the urge to swallow and the pulverized particles were collected. Swallowing threshold parameters were number of chewing cycles, time until 'swallowing', and median particle size of the pulverized particles as determined by sieving the food. Chewing tests were performed twice and outcomes were averaged., Results: The number of chewing cycles until 'swallowing' of subjects with SDA was approximately 1.7 times (p<0.005) that of the controls and this took approximately 1.6 times more time (p<0.01). The median particle size until 'swallowing' did not differ significantly between the groups, but demonstrated large individual differences. Regression analyses indicated that the ratio of median particle size until 'swallowing' of SDA and CDA becomes progressively unfavourable for SDA with increasing numbers of chewing cycles., Conclusions: Subjects with SDA pulverized test 'food' particles to sizes comparable to subjects with CDA, but chewed longer with more chewing cycles until 'swallowing'. Higher numbers of chewing cycles were associated with increasing difference between SDA and CDA regarding the median particle size until 'swallowing'., Clinical Significance: Compared to subjects with CDA, subjects with moderate SDA pulverize test food particles to comparable size by chewing longer before "swallowing". Therefore, overloading the digestive system by swallowing courser food particles is unlikely in SDA. Consequently, replacement of absent molars just to optimize chewing function is not advised., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Unlabelled: The aim of this study was to assess a two-dimensional method to monitor occlusal tooth wear quantitatively using a commercially available ordinary flatbed scanner., Materials and Methods: A flatbed scanner, measuring software and gypsum casts were used. In Part I, two observers (A and B) independently traced scans of marked wear facets of ten sets of casts in two sessions (test and retest). In Part II, three other sets of casts were duplicated and two observers (C and D) marked wear facets and traced the scanned images independently. Intra- and inter-observer agreement was determined comparing measured values (mm(2)) in paired T-tests. Duplicate measurement errors (DME) were calculated., Results: In Part I the test and retest values (10 casts, 218 teeth) of observer A and B did not differ significantly (A: p = 0.289; B: p = 0.666); correlation coefficients were 0.998 (A) and 0.999 (B). "Tracing wear facets" showed a DME of 0.30 mm(2) for observer A and 0.15 mm(2) for observer B. In Part II, assessment of 70 teeth resulted in correlation coefficients of 0.994 for observer C and 0.997 for observer D; no differences between test and retest values were found for C (p = 0.061), although D differed significantly (p = 0.000). The DME for "marking and tracing wear facets" was 0.39 mm(2) (C) and 0.27 mm(2) (D). DME for inter-observer agreement were 0.45 mm(2) (test) and 0.42 mm(2) (re-test)., Conclusion and Clinical Relevance: We conclude that marking and tracing of occlusal wear facets to assess occlusal tooth wear quantitatively can be done accurately and reproducibly., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The 3 dental schools in the Netherlands have the same goals for their graduates, in terms of knowledge and skills, but the contents of the curricula are different. The curricula are all based on the pillars of scientific education, medical education, dental education, and professionalism. Within this construction a student is trained as the manager of an oral health team. At graduation, the new generation of dentists have many (new) competences and relatively limited clinical experience and need support in acquiring clinical experience. Moreover, dentists who have recently graduated may be faced with methods and materials to which they were not introduced in their educational programme. A dentist with considerable clinical experience can test the newly acquired competences of the new generation ofdentists, with the benefit of a critical eye, against (routine) daily practices.

To be able to make a well founded clinical decision on the basis of evidence, the concept of 'evidence based practice' offers a solution by making it possible to select the appropriate knowledge from the increasing amount of scientific clinical information. Competence is required to put the concept (combining the best available scientific clinical evidence, experience and skills of the dentist and preferences of the patient) into practice. To prepare the undergraduate student for future clinical practice, the Nijmegen dental school has adopted evidence based practice to be implemented from the first year of dental training. The experiences of both students and lecturers are modest. The probable reason is that many clinical decisions are (can be) taken on the basis of experience and routine. The challenge is to base life-long learning on the practice of evidence based dentistry.

Purpose: The aim of this retrospective clinical study was to evaluate the performance of direct composite restorations that were placed in patients with severe tooth wear requiring an increase of the occlusal vertical dimension., Methods and Materials: Eighteen patients with severe tooth wear, who had been treated in a private practice between April 1996 and July 2007, were selected. All subjects had been treated with direct composite resin restorations in increased vertical dimension using a three-step etch-and-rinse adhesive system and a hybrid composite resin. From the dental records, information about re-intervention and replacement of restorations was obtained. Patients were then clinically examined to evaluate the status of the restorations and interviewed about their satisfaction with the restorative treatment using a Visual Analogue Scale (VAS)., Results: Eighteen patients (16 male, 2 female with an average age of 44.8 years) with severe tooth wear were included in the study. Time since treatment ranged from 6 months to 12 years and the mean observation time was 3.98 years. Of the 332 restored teeth, 23 restorations showed failures (6.9%). Eight restorations (2.4%) showed major fractures, 11 restorations (3.3%) showed minor fractures, and four restorations (1.2%) failed due to secondary caries. VAS data on a scale of 0 to 10 revealed high patient satisfaction with this type of restoration (mean 9.0)., Conclusion: Treatments with direct hybrid composite restorations placed in an increased occlusal vertical dimension showed good clinical performance in patients with severe tooth wear.

Objective. To assess fracture resistance and failure mode of repaired fiber-reinforced composite (FRC) cusp-replacing restorations. Methods. Sixteen extracted human premolars with fractured cusp-replacing woven (Group (A)) or unidirectional (Group (B)) FRC restorations from a previous loading experiment were repaired with resin composite and loaded to fracture. Results. Differences in fracture loads between groups were not statistically significant (P = 0.34). Fracture loads of repaired specimens were significantly lower than those of original specimens (P = 0.02 for Group (A) and P < 0.001 for Group (B)). Majority of specimens showed failure along the repaired surface. In Group (B) 89% of specimens showed intact tooth substrate after restoration fracture, while this was 28% in Group (A) (P = 0.04). Conclusion. Fractured cusp-replacing FRC restorations that are repaired with resin composite show about half of fracture resistance of original restorations. Mode of failure with a base of unidirectional fibers is predominantly adhesive.

Objectives: The purpose of this clinical study was to evaluate the long-term outcome of three-unit posterior fixed partial dentures (FPDs) made of fiber-reinforced resin composite (FRC), and to identify design factors influencing the survival rate., Methods: 77 patients (52 females, 25 males) received 96 indirectly made FRC FPDs, using pre-impregnated unidirectional glass-fibers, requiring manual wetting, as framework material. FPDs were surface (n=31) inlay (n=45) or hybrid (n=20) retained and mainly located in the upper jaw. Hybrid FPDs consisted of a wing retainer at canine and an inlay retainer at distal abutment tooth. Surface FPDs consisted of uplay and wing combinations. Follow-up period was at minimum 4.5 years, with checkups at every 1-2 years. The study was carried out by six operators in three centers in the Netherlands, Finland and Sweden. Survival rates, including reparable defects of FPDs, and success rates were determined., Results: Kaplan-Meier survival rate at 5 years was 71.2% (SE 4.8%) for success and 77.5% (SE 4.4%) for survival. Differences were not significantly different. Main failure modes were delamination and fracture of the FPD. Only FPDs with surface retainers showed debonding., Conclusions: A success rate of 71% and a survival rate of 78% after 5 years was found. Survival rates of inlay, hybrid and surface retained FPDs did not significantly differ., (Copyright 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.)

Objective. To quantify effects on occlusion and temporomandibular function of mandibular distal extension removable partial dentures in shortened dental arches. Methods. Subjects wearing mandibular extension removable partial dentures (n = 25) were compared with subjects with shortened dental arches without extension (n = 74) and with subjects who had worn a mandibular extension removable partial denture in the past (n = 19). Subjects with complete dentitions (n = 72) were controls. Data were collected at baseline and at 3-, 6-, and 9-year observations. Results. Occlusal activity in terms of reported awareness of bruxism and occlusal tooth wear of lower anterior teeth did not differ significantly between the groups. In contrast, occlusal tooth wear of premolars in shortened dental arches with or without extension dentures was significantly higher than in the controls. Differences amongst groups with respect to signs and symptoms related to temporomandibular disorders were not found. Occlusal support of the dentures did not influence anterior spatial relationship. Occlusal contacts of the denture teeth decreased from 70% for second premolars via 50% for first molars, to 30% for second molars. Conclusions. Mandibular distal extension removable partial dentures in moderate shortened dental arches had no effects on occlusion and temporomandibular function.

Data on the prevalence of tooth wear among children and adolescents are inconsistent. Given the impact of extensive tooth wear for over a lifetime, evidence on the extent is required. The aim was to systematically review the literature on the prevalence of tooth wear in children and adolescents. A PubMed literature search (1980-2008) used the keywords 'tooth' AND 'wear'; 'dental' AND 'attrition' AND 'prevalence'; 'dental' AND 'wear' AND 'prevalence'; 'erosion AND prevalence' AND 'abrasion AND prevalence'. Following exclusion criteria, 29 papers were reviewed using established review methods. There was a total of 45,186 subjects (smallest study 80 and largest study 17,047 subjects) examined from thirteen multiple random clusters, eight multiple convenience clusters and eight convenience clusters. Nine different tooth wear indices were used, but the common denominator among studies was dentin exposure as an indicator of severe wear. Forest plots indicated substantial heterogeneity of the included studies. Prevalence of wear involving dentin ranged from 0 to 82% for deciduous teeth in children up to 7 years; regression analysis showed age and wear to be significantly related. Most of the studies in the permanent dentition showed low dentin exposure, a few reported high prevalence (range 0-54%); age and wear were not related (regression analysis). The results of this systematic review indicate that the prevalence of tooth wear leading to dentin exposure in deciduous teeth increases with age. Increase in wear of permanent teeth with age in adolescents up to 18 years old was not substantiated., ((c) 2010 S. Karger AG, Basel.)

Objectives: To compare polymerization efficiency of resin composite basing materials when light-cured through resin composite and fiber reinforced composite (FRC) by testing microhardness., Methods: Simulated indirect restorations were prepared by application of resin composite (Clearfil AP-X) or FRC (EverStick) to nylon rings with 1.5mm thickness and 8mm diameter, followed by light-curing. Resin composite basing material (Clearfil Majesty Flow or Clearfil AP-X) was applied to identical rings and light-cured through the simulated indirect restorations with exposure times of 20, 40, or 60s. Light-curing though a ring without resin material (=no indirect restoration) served as control. For each combination of basing material and indirect restoration 10 specimens were prepared for each exposure time. Top and bottom surface Vickers microhardness numbers (VHNs) of basing materials were recorded after 24h., Results: After 60s exposure time, VHNs with indirect FRC were not different from control VHNs, while VHNs with indirect resin composite were significantly lower (p<0.001). Linear regression analysis revealed that resin composite basing material used had the greatest effect on top and bottom VHNs (p<0.001). The presence of an indirect restoration resulted in decreased VHNs (p<0.001), with resin composite resulting in lower VHNs when compared to FRC. Moreover, a longer exposure time resulted in increased VHNs (p<0.001)., Significance: Results suggest that polymerization of resin composite basing materials is more effective when light-curing through an FRC than through a resin composite indirect restoration. Prolonging of exposure time, however, is necessary when compared to light-curing without presence of indirect restoration material.

Aim: To explore whether tooth replacement in a southern region of Vietnam is in line with the primary health care approach, aiming at health services for all people at affordable costs., Methods: Tooth replacement was investigated by means of prostheses as delivered by four dental laboratories of which the output was considered representative. Information was based on dental casts related to the prostheses., Results: Prostheses replaced almost all missing teeth, irrespective of the types (interrupted or shortened dental arches) and numbers of missing teeth in the dental arch they were made for. Acrylic removable partial dentures were the most common prostheses delivered (65% of removable partial dentures)., Conclusion: It cannot be stated that dental arch conditions in this study were representative for the southern Vietnamese population. However, it is concluded that dental practitioners tend to provide complete dental arches by tooth replacements. This morphologically based approach might introduce over treatment. In line with primary oral health care, a functionally oriented treatment management, including the shortened dental arch concept, should be implemented.

Objectives: The purpose of this clinical study was to evaluate the long-term outcome of 3-unit anterior fixed partial dentures (FPDs) made of fiber-reinforced resin composite (FRC), and to identify design factors influencing the survival rate., Methods: 52 patients (26 females, 26 males) received 60 indirectly made FRC FPDs, using pre-impregnated unidirectional glass fibers, requiring manual wetting, as framework material. FPDs were surface (n=48) or hybrid (n=12) retained and mainly located in the upper jaw. Hybrid FPDs had a combination of retainers; i.e. crown at one and surface retention at the other abutment tooth. Surface FPDs were either purely adhesively retained (n=29) or with additional mechanical retention (n=19). Follow-up period was at minimum 5 years, with check-ups every 1-2 years. Six operators were involved, in three centers in the Netherlands, Finland and Sweden. Survival rates, including repairable defects of FPDs, and success rates were determined., Results: Kaplan-Meier survival rate at 5 years was 64% (SE 7%). For the level of success, values were 45% (SE 7%) and the estimated median survival time 58 (SE 10.1) months. For surface FPDs, additional mechanical retention did not improve survival significantly. There was a trend towards better survival of surface FPDs over hybrid FPDs, but differences were not significant. Main failure modes were fracture of the FPD and delamination of veneering composite., Significance: A success rate of 45% and a survival rate of 64% after 5 years was found. Fracture of the framework and delamination are the most prevalent failure modes, especially for surface FPDs.

Objectives: Fractured coronal fragments of incisors can be adhered to the remaining tooth with resin composite, but are prone to failure. This study explores whether mini fibre-reinforced composite (FRC) anchors increase fracture resistance of reattached fragments., Methods: Forty-five extracted incisors were randomly divided into three groups. In Groups A and B coronal fragments were reattached to the remaining tooth, with additionally two anchors placed in Group B. In Group C resin composite buildups were made. Specimens were statically loaded until failure occurred. Failure modes were characterized as intact remaining tooth substrate (adhesive or cohesive failure of coronal fragment) or fractured remaining tooth substrate (fracture limited to enamel or extending into dentin)., Results: Mean fracture loads were 255N (SD=108N) for Group A, 599N (SD=465N) for Group B and 786N (SD=197N) for Group C (values significantly different, all p values <0.05). Group A showed purely adhesive failures, while Groups B and C showed 73 and 53% fractures of remaining tooth substrate (p<0.05)., Conclusions: Mini FRC anchors increase fracture resistance of reattached coronal fragments, but induce more remaining tooth substrate fractures.

A proposal for restorative treatment is based on the expected efficiency of the treatment. Efficiency is determined by measuring the investment, such as the monetary and biological cost, against what is gained, such as functional restoration and durability. If one's goal is to save tooth tissue in the restorative process, it is interesting to compare the conventional fixed partial denture with the adhesive fixed partial denture. The mean survival rate of conventional fixed partial dentures clearly exceeds the mean survival rate of adhesive fixed partial dentures but there are biological risks. Loss of vitality of the abutment teeth and the occurrence of caries are more prominent with conventional fixed partial dentures than with adhesive fixed partial dentures. Consequently, the possibility of replacing a conventional fixed partial denture with a new conventional fixed partial denture is limited. Because this and other clinical aspects can not easily be expressed numerically, the patient should be informed qualitatively about the advantages, disadvantages and uncertainties of the various types of fixed partial dentures.

In the past decade, follow-up studies on fiber-reinforced composite fixed partial dentures (FRC FPDs) have been described. Combining the results of these studies to draw conclusions about the effectiveness of FRC FPDs is challenging. The objective of this systematic review was to obtain survival rates of FRC FPDs and to explore the relationships between reported survival rates and risk factors. In a literature-selection procedure on the clinical performance of FRC FPDs, 15 studies, reporting on 13 sets of patients, were analyzed. The Kaplan-Meier estimate of the overall survival, based on the data from all sets of patients (n = 435) was 73.4% (69.4-77.4%) at 4.5 yr. Converted survival rates at 2 yr of follow-up showed substantial heterogeneity between studies. It was not possible to build a reliable regression model that indicated risk factors. The technical problems most commonly described were fracture of the FPD and delamination of the veneering composite.

Purpose: The aim of this study was to investigate data on the prevalence of tooth wear in adults and assess possible correlations using a systematic review., Materials and Methods: A search of the literature, using PubMed and the Cochrane Library, from January 1980 to July 2007 was made using keywords "tooth + wear"; "dental + attrition + prevalence"; "dental + wear + prevalence"; "erosion + prevalence"; and "abrasion + prevalence". References were independently screened for inclusion and exclusion by two investigators and Cohen Kappa was used as the measure of agreement. Data were collected and converted into the Smith and Knight Tooth Wear Index., Results: One hundred eighty-six references were initially selected and subjected to the systematic review procedure; 13 survived the inclusion procedure. Four articles were suitable for regression analysis at tooth level (R2 = .593) and 3 at subject level (R2 = .736), using "age and age squared" and "age squared" as variables, respectively. Six studies reported males having significantly more tooth wear than females., Conclusion: The predicted percentage of adults presenting with severe tooth wear increases from 3% at the age of 20 years to 17% at the age of 70 years. Increasing levels of tooth wear are significantly associated with age.