Análisis tridimensional de la deformación ósea cortical en prótesis parcial fija implantosoportada con voladizo distal sobre implantes cortos en maxilar / Three-dimensional analyisis of cortical bone deformation in implant-supported fixed partial prosthesis with distal cantilever, on short maxillary implants

Objetivo: Analizar la distribución de tensiones que provoca una fuerza axial en el modelo tridimensional, con elmétodo de elementos finitos, en la prótesis parcial fija implantosoportada con voladizo distal (PPFIVD) sobre implantes dentales cortos en el sector posterior del maxilar parcialmente desdentado. Materiales y métodos: Se crearon modelos geométricos del maxilar. Se diseñaron dos grupos y cuatro subgrupos. En zona premolar, se ubicaron implantes cortos StandardPlus SLA® (Straumann) de diferentes longitudes. Grupo A: PPFIVD con dos implantes, GA1 de 8 mm y GA2 de 4 mm. Grupo B: PPFIVD con un implante, GB1 de 8 mm y GB2 de 4 mm. Se aplicó una fuerza axial de 100 N a 30°.Resultados: La distribución de las tensiones en los implantes fue menor en GA1 que en GA2, y en GB1 que enGB2. A nivel óseo, la distribución de las tensiones fue mayor en GA1 que en GA2, y en GB2 que en GB1. Se observaron microdeformaciones óseas periimplante y, posteriormente, desplazamiento del conjunto prótesis/implante. Conclusiones: La PPFIVD sobre dos implantes de 8 y4 mm ferulizados podría ser una alternativa viable al levantamiento del piso de seno maxilar. La PPFIVD sobre un implante de 4 mm no sería recomendable. Las tensiones elevadas provocaron menor rendimiento en geometría oseoimplantaria, evidenciando microdeformaciones en el tejido óseo tridimensional y desplazamientos de la PPFIVD.

Oral physiology, nutrition and quality of life in diabetic patients associated or not with hypertension and beta-blockers therapy.

The relationship between type 2 diabetes oral physiology, nutritional intake and quality of life has not been fully elucidated. We assessed the impact of type 2 diabetes - exclusive or associated with hypertension with beta-blockers treatment - on oral physiology, mastication, nutrition and quality of life. This cross-sectional study was performed with 78 complete dentate subjects (15 natural teeth and six masticatory units minimum; without removable or fixed prostheses), divided into three groups: diabetics (DM) (n = 20; 45·4 ± 9·5 years), diabetics with hypertension and receiving beta-blockers treatment (DMH) (n = 19; 41·1 ± 5·1 years) and controls (n = 39; 44·5 ± 11·7 years) matched for gender, age and socioeconomic status. Blood glucose, masticatory performance, swallowing threshold, taste, food intake, stimulated and unstimulated salivary flow, pH and buffering capacity of saliva were assessed. Glycemia was higher in DM than in controls (P < 0·01). No differences were observed between DM and controls for nutrition and quality of life. Both stimulated and unstimulated salivary flow rate were lower in DMH (P < 0·01), which also presented the lowest number of teeth and masticatory units (P < 0·0001), and reduction in the number of chewing cycles (P < 0·01). Controls showed lower Decayed Missing Filled Teeth index (DMFT) scores in comparison with DMH (P = 0·021). Masticatory performance and saliva buffering capacity were similar among groups. Exclusive type 2 diabetes did not alter oral physiology, nutrition or quality of life. However, when hypertension and beta-blockers treatment were associated with diabetes, the salivary flow rate, chewing cycles and number of teeth decreased.

Impact of Different Prosthodontic Treatment Modalities on Nutritional Parameters of Elderly Patients.

PURPOSE: To assess dietary and nutritional changes among the elderly following pros-thodontic rehabilitation. Another objective was to study the relationship, if any, between diet and nutrition, with extent of edentulism and different types of prosthodontic treatment. MATERIALS AND METHODS: One hundred and thirty-five patients who satisfied the inclu-sion and exclusion criteria and agreed to be a part of the study after informed consent were recruited to this longitudinal study. Following selection, they were investigated on four aspects: dental examination, dietary assessment, anthropometric assessment, and serum biochemical assessment. All measurements were collected twice, first at baseline and then 6 months following prosthodontic rehabilitation. Treatment modalities included were complete denture (CD), removable partial denture (RPD), and fixed partial denture (FPD). The RPD group was of two types: distal extension prosthesis (RPDD) and tooth-supported prosthesis (RPDT). Change (post-pre) in outcome measures was compared by one-way ANOVA, and significance of mean difference between the groups was done by Tukey's honestly significance difference post hoc test. RESULTS: The improvement in diet was found to be: CD > RPDD > RPDT > FPD. Significant improvement in weight (p < 0.001), BMI (p < 0.001), protein (p < 0.001), carbohydrate (p = 0.021), calorie (p < 0.001), iron (p = 0.002), and vitamin B (p < 0.001) in group CD as compared to partially edentulous patients (group RPDD + RPDT + FPD) was noted. The protein and calorie intake increased significantly in group RPD as compared to group FPD in partially edentulous patients. CONCLUSION: Prosthetic rehabilitation becomes increasingly important as the level of edentulism increases to improve dietary, anthropometric, and biochemical parameters.

Impact on Dietary Intake of Removable Partial Dentures Replacing a Small Number of Teeth.

The aim of this study was to clarify the impact of wearing removable partial dentures (RPDs) replacing a small number of teeth on dietary intake. Participants had at least 20 teeth and were classified as Eichner B1 or B2. The participants underwent dental and oral examinations, and their dietary intake was assessed. Analysis of covariance showed that RPD wearers consumed more vegetables, n-3 fatty acids, calcium, vitamin A, and dietary fiber than nonwearers after adjusting for possible confounding factors. It is concluded that RPDs are effective for improving dietary intake even in participants who have lost a small number of teeth.

A comparison of two dental implant systems in partially edentulous patients: 1-year post-loading results from a pragmatic multicentre randomised controlled trial.

PURPOSE: To compare the clinical effectiveness of two implant systems: Way Milano and Kentron (Geass, Pozzuolo del Friuli, UD, Italy). MATERIALS AND METHODS: A total of 64 patients requiring at least two single crowns or partial fixed dental prostheses supported by a maximum of three implants had their sites randomised according to a split-mouth design to receive both implant systems at six centres. Patients were followed up for 1 year after initial loading. Outcome measures were: prosthesis/implant failures; any complication; peri-implant marginal bone level changes; and clinician preference. RESULTS: In total 71 Way Milano and 73 Kentron implants were placed. Six patients dropped-out before the 1-year follow-up, but all remaining patients were followed up to 1 year post-loading. No Way Milano implant failed, whereas three Kentron implants failed before loading. Two complications were reported, one for each implant type. There were no statistically significant differences for prosthesis/implant failures (difference in proportions = 0.05, P = 0.25; 95% CI -0.02 to 0.13) and complications (difference in proportions = 0, P = 1.0, 95% CI -0.07 to 0.07) between the implant systems. Three operators preferred Way Milano implants whereas the other three had no preference. At implant placement (baseline) bone levels were higher for Way Milano implants (0.27 mm) than for Kentron implants (0.41 mm). Both groups gradually lost statistically significant amounts of periimplant marginal bone at 4 months after loading and at 1 year after loading. One year after loading, Way Milano implants lost an average of 0.73 mm peri-implant bone compared with 0.84 mm of Kentron implants. Marginal bone level changes were not statistically significant different for Way Milano compared to Kentron implants at 4 months (-0.16 mm, 95% CI -0.30, 0.01; P = 0.0606) and 1 year (-0.09 mm, 95% CI -0.26, 0.09; P = 0.3407) after loading. CONCLUSIONS: No statistically significant differences were observed between the two implant types, although three Kentron implants failed versus none of the Way Milano type. Longer follow-up of wider patient populations are needed to better understand whether there is an effective advantage with one of the two implant designs.

Treatment planning and dental rehabilitation of periodontally compromised partially edentulous patient: a case report - part II.

When planning a prosthetic rehabilitation of a periodontally compromised case, the clinician is often confronted with difficulties and dilemmas related to selecting the appropriate treatment that would provide long-term successful outcomes in function and esthetics. In such cases, a correct diagnosis and prognosis of the intraoral situation supported by evidence-based dentistry is the basis for the establishment of a proper treatment strategy. In this second part of a two-part treatment planning series, a systematic approach of patient examination and prognosis of each tooth is presented. Furthermore, different removable and fixed treatment possibilities are described and the rationale governing the decision-making process is revealed. The execution of the final treatment plan as specified by the concept of comprehensive dental care is outlined, and the final outcome is discussed according to the literature.

Influence of implant surface topography on bone-regenerative potential and mechanical retention in the human maxilla and mandible.

PURPOSE: To evaluate the short- and mid-term effects of commercial pure (cp) titanium implant surface topography on osseointegration, bone-regenerative potential and mechanical retention in the human maxilla and mandible. METHODS: 32 micro-implants with the same geometry but with four different surface treatments were implanted in the maxilla and mandible of eight patients. Each patient received four micro-implants, one of each type. Percentage of bone-to-implant contact analysis and histological evaluation was carried 3, 6 and 12 weeks after implantation. Furthermore, reverse removal torque tests were conducted 3 and 6 weeks after implantation to analyze functional bone attachment. Implant surfaces tested were: machined, grit-blasted, acid-etched, and grit-blasted with acid-etch. One-way ANOVA was performed using the multiple comparison Fisher's test to determine significance of observed differences among test groups. The level of significance was established at 5% (P < 0.05). Mean and standard deviations of the test groups were calculated. RESULTS: Surface roughness had a significant correlation with the evolution of bone regeneration. The surfaces with roughness Ra approximately 4 microim (grit-blasted and grit-blasted with acid-etch), showed rapid tissue colonization compared to machine and acid-etched surfaces. The results of reverse removal torque tests confirmed a significant correlation between surface roughness and functional bone attachment. Grit-blasted and grit-blasted with acid etched surfaces showed higher retention values compared to machine and acid-etched implants. This finding was supported by higher bone-to-implant contact observed for rougher surfaces (grit-blasted and grit-blasted with acid etching).

Treatment planning and dental rehabilitation of a periodontally compromised partially edentulous patient: a case report - Part I.

When planning a prosthetic rehabilitation of a periodontally compromised case, the clinician is often confronted with difficulties and dilemmas related to selecting the appropriate treatment modality that would provide a long-term longevity in terms of function and esthetics. In such cases, a correct diagnosis and prognosis of the intraoral situation supported by evidence-based dentistry is the basis for the establishment of a proper treatment strategy. In this two-part treatment planning series, a systematic approach of patient examination and prognosis of each tooth is presented. Furthermore, different removable and fixed treatment possibilities are described and the rationale governing the decision-making process is revealed. The execution of the final treatment plan as specified by the concept of comprehensive dental care is outlined and the final outcome is discussed according to the literature.

Mastication and jaw motion of partially edentulous patients are affected by different implant-based prostheses.

The main goal of prosthetic treatment is to restore masticatory function. However, insufficient evidence supports the recommendation of one specific prosthetic intervention for partially edentulous patients. Function after the use of three different prostheses by the same partially edentulous subject. Mastication was assessed in 12 subjects (mean age 62.6 ± 7.8 years) after they had used removable partial dentures (RPDs), implant-supported partial dentures (IRPDs) and implant-fixed partial dentures (IFPDs). Masticatory ability (MA) was estimated by visual analogue scale questionnaire, while the mandibular chewing motion was evaluated by kinesiographic device, representing an objective measurement of masticatory function. Data were analysed by repeated-measures anova followed by Tukey-Kramer (P < 0.05). MA improved after IRPD and IFPD use (P < 0.05). Opening, closing and total cycle time duration were reduced after both IRPD and IFPD use (P < 0.05), irrespectively the implant prosthesis type. IFPDs and IRPDs restore the masticatory function of partially edentulous patients better than RPDs.

Interdisciplinary treatment of a periodontally compromised adult patient with multiple missing posterior teeth.

This article reports the comprehensive, interdisciplinary treatment of a 50-year-old periodontally compromised adult patient with multiple missing posterior teeth. After initial periodontal treatment, the maxillary first molars and right central incisor were intruded orthodontically. Miniscrews were used to intrude the maxillary first molars by 3 mm. The mandibular arch was restored with a tooth-supported overdenture. Root coverage of the maxillary right central incisor was performed using Alloderm (Biohorizons, Birmingham, Ala). At the end of the interdisciplinary therapy, the results were esthetically pleasing, with the patient's oral functions restored to the optimum. The emphasis of this report is to highlight the importance of integrating various specialties such as periodontics, orthodontics, endodontics, and restorative dentistry toward a common goal of improving the patient's oral health, function, and esthetics.

Growth factor-mediated vertical mandibular ridge augmentation: a case report.

Posterior vertical alveolar ridge deficiencies are challenging defects to treat predictably and often require autogenous bone-harvesting procedures. Traditional treatment modalities, eg, guided bone regeneration, distraction osteogenesis, and autogenous grafts, present with a number of potential complications and limited success when used to restore vertical ridge height. Recent advances in recombinant growth factor technology may provide viable, alternative therapies for the treatment of significant alveolar ridge deficiencies. This proof-of-principle case report examines the utility and effectiveness of using a composite graft of freeze-dried bone allograft and recombinant human platelet-derived growth factor BB in conjunction with an overlying titanium mesh to regenerate well-vascularized bone in a significant posterior mandibular ridge defect prior to implant placement. The important role of the overlying periosteum as a possible key source of osteogenic cells during growth factor-enhanced regenerative procedures is emphasized.

Incidence and prevalence of dental-periodontal conditions and edentation in Moldavia.

UNLABELLED: The proper rehabilitation of the partially extended edentulous patient should lead to a state of balance between the components of the stomatognathic system and the therapeutic option selected for an as long as possible. AIM: To outline the importance of a holistic biological perspective on the body-stomatognathic system relationships and the need for complex rehabilitation in view of obtaining a long lasting balance. MATERIAL AND METHODS: 3340 individuals from urban and rural areas of Iasi County were evaluated. The evaluation was based on the correlation of physical exam with data from a specially drafted questionnaire aimed at determining oral health behavior pattern, a sine-qua-non condition for a clear identification of oral conditions specific to the study area. RESULTS: General health status was poor in 72.1% of the subjects from rural areas as compared to 27.9% in those from rural areas, with cardiovascular diseases ranking first but with higher rates in urban than in rural areas. In urban areas, odontal lesions were the most common and had a higher prevalence in 2012 than in the previous years, followed by the periodontal lesions with the same ascending trend in 2012. CONCLUSIONS: Continuity with regard to the prophylaxis of general and oral conditions in the lasi County in both rural and urban areas is a must, health education being essential for improving population health.

Telescopic crowns: extra-oral and intra-oral retention force measurement--in vitro/in vivo correlation.

OBJECTIVE: This study deals with the determination of the retentive forces of telescopic crowns measured extra- and intra-orally and the correlation of these values. BACKGROUND: The telescopic denture is a well-documented solution for prosthetic rehabilitation for a partially edentulous jaw. Acceptable retention forces are needed to avoid inadvertent removal of the denture during movement of the jaws. Recent literature suggests 3-7 N per attachment to be acceptable. These values are only supported by in vitro studies. In vivo data are scarce, and a correlation of the in vitro and in vivo values is lacking. MATERIAL AND METHODS: Twenty-five combined fixed-removable prostheses with a total of 72 double crowns were used for extra-oral retention force measurement prior to cementation (in vitro). The intra-oral measurement was performed at 72 defined measuring points of the dentures 4-6 weeks after prosthetic rehabilitation (in vivo). A specifically designed measuring device was used. RESULTS: The rank correlation showed that the in vitro and in vivo values correlate with each other (Spearman's ρ = 0.5052). Additionally, it was found that the median values measured before (1.97N) insertion of the dentures were significantly lower than after (4.70N) insertion (Mann-Whitney test, p ≤ 0.0001). CONCLUSION: The retention forces measured before and after insertion of the denture correlate with each other although their dimension is significantly higher after insertion. The reason for this behaviour might be some tilting during removal. Nevertheless, the correlation allows a prediction of the clinically relevant forces by a measurement of the extra-orally measured retentive values.

Dental treatment needs in Dutch nursing homes offering integrated dental care.

The purpose of this study was to determine the dental treatment needs of the residents in nursing homes (NHs) where integrated dental care has been offered without financial barriers. The dental status and surgical, prosthetic, restorative, and periodontal treatment needs were determined for 432 residents (average age 78.8 years) in three Dutch NHs. Although the subjects had no complaints, 72% had dental treatment needs. It was determined that treatment was necessary for 64% of the edentulous subjects (N = 316), 100% of the partially dentate subjects (N = 76), and 87% of the fully dentate subjects (N = 40). We concluded that when residents can no longer carry out oral hygiene independently, it is very difficult for them to maintain a level of oral health where their dental treatment needs have been met, especially for dentate residents.

Osseoperception: active tactile sensibility of osseointegrated dental implants.

PURPOSE: The phenomenon of developing a certain tactile sensibility through osseointegrated dental implants is called osseoperception. Active tactile sensibility can be tested by having the subject bite on test bodies. The aim of the study was to describe the active tactile sensibility of single-tooth implants based on the 50% value and the slope of the sensibility curve at the 50% value. MATERIALS AND METHODS: Sixty-two subjects with single-tooth implants with natural opposing teeth were included in the study. In a computer-assisted and randomized way, copper foils of varying thickness (0 to 200 Μm) were placed inter?occlusally between the single-tooth implant and the natural opposing tooth, and the active tactile perception was studied according to the psychophysical method of constant stimuli and statistically evaluated by logistic regression. RESULTS: Tactile perception of the implants at the 50% value estimated by logistic regression was 20.2 ± 10.9 Μm on average, and the slope was 29 ± 15. Regarding implant surface structure, significant differences were observed. The sandblasted and acid-etched surface was significantly more sensitive than the titanium plasma-sprayed surface, and the machined surface was similar to the titanium plasma-sprayed surface. CONCLUSIONS: Active tactile sensibility of implants with natural antagonistic teeth is very similar to that of teeth, but the slope of the tactile sensibility curve is flatter. Significant differences in tactile sensibility as a function of different implant surfaces may indicate that receptors near the implant form the basis of osseoperception.

Prosthetic gingival reconstruction in a fixed partial restoration. Part 1: introduction to artificial gingiva as an alternative therapy.

The Class III defect environment entails a vertical and horizontal deficiency in the edentulous ridge. Often, bone and soft tissue surgical procedures fall short of achieving a natural esthetic result. Alternative surgical and restorative protocols for these types of prosthetic gingival restorations are presented in this three-part series, which highlights the diagnostic and treatment aspects as well as the lab and maintenance challenges. A complete philosophical approach involves both a biologic understanding of the limitations of the hard and soft tissue healing process as well as that of multiple adjacent implants in the esthetic zone. These limitations may often necessitate the use of gingiva-colored "pink" restorative materials and essential preemptive planning via three-dimensional computer-aided design/computer-assisted manufacture to achieve the desired esthetic outcome. The present report outlines a rationale for consideration of artificial gingiva when planning dental prostheses. Prosthetic gingiva can overcome the limitations of grafting and should be a consideration in the initial treatment plan. (Int J Periodontics Restorative Dent 2009;29:471-477.).

Comparison of the pain levels of computer-controlled and conventional anesthesia techniques in prosthodontic treatment.

OBJECTIVE: The objective of this study was to compare the pain levels on opposite sides of the maxilla at needle insertion during delivery of local anesthetic solution and tooth preparation for both conventional and anterior middle superior alveolar (AMSA) technique with the Wand computer-controlled local anesthesia application. MATERIAL AND METHODS: Pain scores of 16 patients were evaluated with a 5-point verbal rating scale (VRS) and data were analyzed nonparametrically. Pain differences at needle insertion, during delivery of local anesthetic, and at tooth preparation, for conventional versus the Wand technique, were analyzed using the Mann-Whitney U test (p=0.01). RESULTS: The Wand technique had a lower pain level compared to conventional injection for needle insertion (p<0.01). In the anesthetic delivery phase, pain level for the Wand technique was lower (p<0.01). However, there was no difference between the Wand and conventional technique for pain level during tooth preparation (p>0.05). CONCLUSIONS: The AMSA technique using the Wand is recommended for prosthodontic treatment because it reduces pain during needle insertion and during delivery of local anaesthetic. However, these two techniques have the same pain levels for tooth preparation.

Comparison of the pain levels of computer-controlled and conventional anesthesia techniques in prosthodontic treatment

OBJECTIVE: The objective of this study was to compare the pain levels on opposite sides of the maxilla at needle insertion during delivery of local anesthetic solution and tooth preparation for both conventional and anterior middle superior alveolar (AMSA) technique with the Wand computer-controlled local anesthesia application. MATERIAL AND METHODS: Pain scores of 16 patients were evaluated with a 5-point verbal rating scale (VRS) and data were analyzed nonparametrically. Pain differences at needle insertion, during delivery of local anesthetic, and at tooth preparation, for conventional versus the Wand technique, were analyzed using the Mann-Whitney U test (p=0.01). RESULTS: The Wand technique had a lower pain level compared to conventional injection for needle insertion (p<0.01). In the anesthetic delivery phase, pain level for the Wand technique was lower (p<0.01). However, there was no difference between the Wand and conventional technique for pain level during tooth preparation (p>0.05). CONCLUSIONS: The AMSA technique using the Wand is recommended for prosthodontic treatment because it reduces pain during needle insertion and during delivery of local anaesthetic. However, these two techniques have the same pain levels for tooth preparation.

[Role of computerised programs for the evaluation, diagnosis and treatment of partially edendulous patients]. / Aportul programelor computerizate in evaluare, diagnostic si tratament la pacientul edentat partial.

UNLABELLED: In order to elaborate a correct plan of diagnosis and find the correct therapeutic solution of election in partial edentulous it would be necessary to use a Support System for Clinical Decisions (SSCD). This may bring many benefits both to the private medical assistance,and to institutions with wider therapeutic, educational and scientific objectives. MATERIALS AND METHODS: Using as starting point the ProDent platform of application existing at the Faculty of Dental Medicine from The University of Medicine and Pharmacy Gr.T. Popa Iasi we have developed an expert system for clinical case evaluation and for providing a reliable therapeutic solution. In this respect we have used the ProDent application database--a complete and complex database which records information about patients. RESULTS: At the same time the application generates a table recording a clinico-biological data hierarchy, highlighting the categories which may require intervention during the specific preparation stage. The use of bayes inference also indicates the most reliable therapeutic solution, the initial plan of treatment, the reliability score and the oral rehabilitation predictions. By adding the patient initial score and the oral rehabilitation predictions provided by the application, we obtain the patient initial therapeutic score. CONCLUSIONS: The simulation programs and the electronic format of the observation paper are efficient tools that provide an integrative holistic approach of patients with different forms of oral pathology, under the incidence of local, loco-regional and general complications.

The biologic stability of alumina-zirconia implant abutments after 1 year of clinical service: a digital subtraction radiographic evaluation.

The purpose of the present clinical study was to evaluate the biologic stability of alumina-zirconia implant abutments by histologic and radiographic examination. Nineteen partially edentulous patients were treated with 37 external-hexagon implants. After a healing period of 3 to 6 months, alumina-zirconia abutments were connected and restored with cemented single crowns or short-span fixed partial dentures. Periapical radiographs were taken at the time of prosthesis delivery and after 3, 6, and 12 months of follow-up. Crestal alveolar bone level changes were assessed by digital subtraction of consecutive images, and 1-way analysis of variance was used for statistical analysis. No implant, abutment, or restoration failed during the observation period. Bone level changes were statistically insignificant and histologic examination revealed no signs of inflammation. Stable and healthy soft and hard tissue conditions may be expected around alumina-zirconia abutments after 1 year of clinical service. However, long-term data are needed to confirm the present results.