Edentulous Areas (edentulous + area)

Distribution by Scientific Domains


Selected Abstracts


Detection of improvement in the masticatory function from old to new removable partial dentures using mixing ability test

JOURNAL OF ORAL REHABILITATION, Issue 9 2005
A. ASAKAWA
summary, The aim of this study was to determine the sensitivity of the Mixing Ability Test to detect improvement of masticatory function in subjects on transition from old to new removable partial dentures. Thirty-two subjects (seven males, 25 females, mean age 65·0 years) with distal extension partially edentulous area in mandible and/or maxilla participated in the study. The following reasons were presented for replacing the old removable partial dentures with new ones: fracture and/or poor fitness of retainers, extraction of abutment teeth, poor fitness of denture base, severe wear of artificial teeth and request for metal base dentures. Masticatory function with old and new removable partial dentures after an adaptation period (mean 27·4 weeks) was evaluated by the Mixing Ability Test. Subjects were asked to masticate five two-coloured wax cubes with each removable partial denture. Mixing Ability Index was obtained from the colour mixture and shape of the masticated cubes. Wilcoxon signed-rank test was used to test the difference of Mixing Ability Indexes between old and new removable partial dentures. The mixing ability indexes with new removable partial dentures (mean ± s.d.: 0·70 ± 0·68) was significantly higher (P < 0·001) than those with old removable partial dentures (,0·11 ± 1·13). The results suggest that the Mixing Ability Test was capable of detecting improvement in masticatory function with new removable partial dentures. [source]


Influence of preimplant surgical intervention and implant placement on bone wound healing

CLINICAL ORAL IMPLANTS RESEARCH, Issue 5 2003
Christer Slotte
Abstract: The aims of the present investigation were to study (1) the influence of preimplant (4 weeks) surgical intervention and (2) the influence of the implant placement per se on bone density and mineralized bone,implant contact (BIC) at implant sites in the rabbit jawbone. The experiment was performed in the edentulous area of the maxillas of 16 adult rabbits. In eight rabbits, the alveolar bone on the left side (test) was surgically exposed and a groove was prepared in the bone crest. Trabecular bone and marrow tissue were removed, and a bioabsorbable barrier membrane was placed to cover the groove. The right side underwent no treatment and served as the control. Four weeks later, a screw-shaped titanium implant was placed transversally through the maxilla, penetrating both the test and the control areas. After another 4 weeks of healing, the animals were killed to obtain ground sections for histomorphometry. Untreated jaws from eight rabbits served as reference specimens. In the rabbits subjected to surgery, the areas (mm2) of both mineralized bone and marrow tissue were similar for test and control (4.9 ± 1.7 vs. 5.1 ± 2.2 and 6.3 ± 5.7 vs. 6.8 ± 5.7 for bone and marrow, respectively). The BIC (%) for all threads was significantly lower on the test side than on the control side (32.1 ± 27.7 vs. 47.7 ± 20.3). The bone density (%) of the total experimental area was similar for test and control (48.5 ± 12.1 vs. 46.5 ± 9.3), as was the bone density in the area within the implant thread valleys and their mirror areas (43.0 ± 13.9 vs. 41.3 ± 13.5, and 40.2 ± 11.0 vs. 40.3 ± 7.2 for thread area and mirror area, respectively). The bone density of the total experimental area in the untreated rabbits was 35.9 ± 5.2%. This value was significantly lower than the values in the total experimental areas (test and control) of the surgically treated rabbits. Similarly, the density of the reference area in the untreated rabbits was 25.4 ± 5.3%, which was also significantly lower than the bone density of the periimplant area of the surgically treated rabbits. We conclude that the surgical trauma caused by the placement of implants in the maxilla of rabbits significantly enhanced the bone density of the implant sites. Surgical intervention in the implant sites 4 weeks prior to the implant placements, however, did not further enhance bone density or BIC. Résumé Les buts de cette étude ont été d'étudier 1) l'influence d'une intervention chirurgicale préimplantaire (4 semaines) et 2) l'influence du placement de l'implant per se sur la densité osseuse et le contact implant-os minéralisé (BIC). Cette expérience a été effectuée dans la région édentée du maxillaire de seize lapins adultes. Chez huit lapins, l'os alvéolaire du côté gauche (test) était chirurgicalement exposé et une marque a été faite dans la crête osseuse. L'os trabéculaire et le tissu spongieux ont été enlevés et une membrane biorésorbable a été placée pour couvrir ce trou. Le côté droit ne subissait aucun traitement et a servi de contrôle. Quatre semaines après, un implant en titane vis a été placé transversalement à travers le maxillaire pénétrant tant la zone test que contrôle. Après quatre semaines de guérison les animaux ont été tués pour obtenir des coupes pour l'histomorphométrie. Les mâchoires non-traitées de huit lapins ont servi de spécimens de référence. Chez les lapins soumis à la chirugie les zones d'os minéralisé et de tissu spongieux étaient semblables pour le test et le contrôle (respectivement 4,9±1,7 mm2 vs 5,1±2,2 mm2 et 6,3±5,7 mm2 vs 6,8±5,7mm2). Les BIC pour tous les filetages étaient significativement moins importants au niveau des tests que des contrôles (32,1±27,7% vs 47,7±20,3%). La densité osseuse du total de l'aire expérimentale était semblable pour les tests et les contrôles (48,5±12,1%vs 46,3±9,3%) comme l'était la densité osseuse dans la zone à l'intérieur du filetage de l'implant et de leurs aires mineures (43,0±13,9%vs 41,3±13,5% pour les filetages et 40,2±11,0% vs40,3±7,2% pour les aires mineures). La densité osseuse de l'aire expérimentale totale chez les lapins nont-traités était de 35,9 ±5,2%. Cette valeur était significativement inférieure à celles dans les aires expérimentales totales (tests et contrôles) des lapins traités chirurgicalement. Parallèlement, la densité de l'aire de référence des lapins non-traités était de 25,4±5,3% c.-à-d. inférieure à la densité osseuse de la zone paroïmplantaire des lapins traités chirurgicalement. Le trauma chirurgical causé par le placement d'implants dans le maxillaire de lapins augmente significativement la densité osseuse au niveau des sites implantaires. L'intervention chirurgicale des sites à implanter quatre semaines avant le placement des implants n'avait cependant augmenté ni la densité osseuse ni le BIC. Zussammenfassung Der Einfluss eines praeimplantären chirurgischen Eingriffes und der Implantation per se auf die Heilung der Knochenwunde. Eine Studie am Kieferknochen des Kaninchens. Ziel: Das Ziel dieser Studie war es 1) den Einfluss eines praeimplantären chirurgischen Eingriffes (4 Wochen vorher) und 2) den Einfluss der Implantation per se auf die Knochendichte und den mineralisierten Knochen-Implantatkontakt (BIC) an einer Implantationsstelle im Kieferknochen des Kaninchens zu untersuchen. Material und Methode: Die Testregion war der zahnlose Oberkieferabschnitt von 16 ausgewachsenen Kaninchen. Bei 8 Kaninchen wurde der Alveolarknochen der linken Seite (Test) chirurgisch freigelegt und eine Vertiefungen in den Knochenkortex präpariert. Dann entfernte man den trabekulären Knochen und das Knochenmark und deckte die Vertiefung mit einer bioresorbierbaren Membran ab. Die rechte Seite wurde unbehandelt belassen und diente als Kontrolle. Vier Wochen später implantierte man ein schraubenförmiges Titanimplantat transversal durch die Maxilla, so dass es Test- oder Kontrollregion durchdrang. Nach einer Heilphase von weiteren vier Wochen wurden die Tiere geopfert und von der zu untersuchenden Region Grundschnitte für die Histologie hergestellt. Als Referenz dienten unbehandelte (jungfräuliche) Kiefer von weiteren 8 Kaninchen. Resultate: Bei den Kaninchen, welche die oben beschriebenen chirurgischen Schritte durchlaufen haben, waren sowohl bei der Test- wie auch bei der Kontrollgruppe die Fläche von mineralisiertem Knochen und Knochenmark (in mm2) ähnlich gross (4.9+1.7 gegenüber 5.1+2.2 beim Knochen und 6.3+5.7 gegenüber 6.8+5.7 beim Knochenmark). Der BIC (%) war in allen Schraubenwindungen auf der Testseite signifikant tiefer als auf der Kontrollseite (32.1+27.7 gegenüber 47.7+20.3). Die Knochendichte (%) war in der untersuchten Region bei der Test- und Kontrollseite etwa gleich gross (48.5+12.1 gegenüber 46.5+9.3) wie die Knochendichte in den Vertiefungen der Schraubenwindungen und ihrer spiegelbildlichen Regionen (43.0+13.9 gegenüber 41.3+13.5 in den Schraubenwindungen und 40.2+11.0 gegenüber 40.3+7.2 in den spiegelbildlichen Regionen). Die Knochendichte in der gesamten Region der unbehandelten (jungfräulichen) Kaninchen betrug 35.9+5.2%. Dieser Wert war signifikant tiefer als die Werte der gesamten untersuchten Region der chirurgisch behandelten Kaninchen (Test- und Kontrollseite). Ganz ähnlich war die Dichte in der Referenzregion der unbehandelten Kaninchen 25.4+5.3%, ein Wert der auch signifikant tiefer war als die Knochendichte in der periimplantären Region von chirurgisch behandelten Kaninchen. Zusammenfassung: Das chirurgische Trauma, das beim Setzen eines Implantates im Oberkiefer von Kaninchen entsteht, begünstigt die Knochendichte an den Stellen der Implantate signifikant. Der chirurgischen Eingriff vier Wochen vor der Implantation jedoch, förderte an den zur Implantation vorgesehenen Stellen weder Knochendichte noch BIC. Resumen Objetivos: La intención de la presente investigación fue estudiar 1) la influencia de la intervención quirúrgica (4 semanas) periimplantaria y 2) la influencia de la colocación de implantes per se en la densidad ósea y el contacto del hueso mineralizado al implante (BIC) en los lugares de implante en el hueso mandibular del conejo. Material y métodos: El experimento se realizó en el área edéntula del maxilar de 16 conejos adultos. Se expuso quirúrgicamente el hueso alveolar en el lado izquierdo (test) de 8 conejos y se preparó un hueco en la cresta ósea. Se retiró el hueso trabecular y el tejido de médula ósea, colocándose una membrana de barrera biorreabsorbible para cubrir el hueco. El lado derecho no sufrió ningún tratamiento y sirvió de control. Cuatro semanas mas tarde, se colocó un implante de forma roscada transversalmente a través del maxilar, penetrando las áreas de prueba y de control. Tras otras 4 semanas de cicatrización, los animales se sacrificaron para obtener cortes histológicos para histomorfometría. Las mandíbulas sin tratar de los 8 conejos sirvieron como especímenes de referencia. Resultados: En los conejos sometidos a cirugía las áreas (mm2) del hueso mineralizado y del tejido medular fueron similares para la prueba y el control (4.9 ± 1.7 vs. 5.1 ± 2.2 y 6.3 ± 5.7 vs. 6.8 ± 5.7, hueso y médula respectivamente). El BIC (%) para todas las roscas fue significativamente mas bajo en el lado de prueba que en el de control (32.1 ± 27.7 vs. 47.7 ± 20.3). La densidad de ósea (%) de toda el área experimental fue similar para la prueba y el control (48.5 ± 12.1 vs. 46.5 ± 9.3) así como la densidad ósea en el área en los valles entre las roscas y en su área espejo (43.0 ± 13.9 vs. 41.3 ± 13.5, y 40.2 ± 11.0 vs. 40.3 ± 7.2, área de roscas y área espejo respectivamente). La densidad ósea en el área total experimental en los conejos no tratados (vírgenes) fue del 35.9 ± 5.2%. Este valor fue significativamente mas bajo que los valores en el total de las áreas experimentales (test y control) de los conejos tratados quirúrgicamente. Del mismo modo, la densidad del área de referencia de los conejos no tratados fue de 25.4 ± 5.3%, que también fue significativamente mas baja que la densidad ósea del área periimplantaria de los conejos tratados quirúrgicamente. Conclusión: El trauma quirúrgico causado por la colocación de implantes en el maxilar de conejos estimuló significativamente la densidad ósea de los lugares de implantes. Sin embargo, la intervención quirúrgica de los lugares de implantes 4 semanas antes de la colocación de los implantes no estimuló mas la densidad ósea o el BIC. [source]


Changes in the bucco-lingual thickness of the mandibular alveolar process and skeletal bone mineral density in dentate women: a 5-yr prospective study

EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 2 2005
Grethe Jonasson
After tooth extraction there is a great interindividual variation in the remodelling pattern of the alveolar process in edentulous areas, with some individuals losing little bone and others undergoing extensive resorption. However, little is known about possible longitudinal changes in the dentate region of the alveolar process of adults and if these are related to alterations in the skeletal bone mineral density (BMD). In a prospective study, on two occasions, 5-yr apart, the BMD of 117 women was determined in the distal forearm by using dual-energy X-ray absorptiometry, and the bucco-lingual thickness of the mandibular alveolar process was measured on dental casts by using a dial calliper. A decrease in the mean alveolar thickness, exceeding a cut-off value of 0.1 mm, was found in 60% of the women and an increase was found in 3% of the individuals. This decrease was 0.22 ± 0.20 mm in the posterior region and 0.16 ± 0.19 mm in the anterior region. The changes in alveolar thickness in the posterior region were significantly correlated to the BMD changes both on the mid-crestal level site and on the cervical level site. We conclude that the bucco-lingual thickness decreases with age in the dentate alveolar process, possibly owing to periosteal resorption related to skeletal bone loss. [source]


Prosthodontic decision-making: what unprompted information do dentists seek before prescribing treatment?

JOURNAL OF ORAL REHABILITATION, Issue 1 2010
R. OMAR
Summary, This study explored the nature of the unprompted information that clinicians seek before making a treatment decision and whether this decision corresponded with the clinical parameters of the case. Interns, general practitioners (GP) and prosthodontists (n = 70, mean age 33 years, range 23,68) were presented with a written vignette of partial edentulism that included two spaces and were invited to ask any questions for the purpose of making a treatment recommendation. A list of 48 potential question/answer items was available to the interviewer, of which 38 were asked. These were then allotted to four thematic categories. Mean number of questions asked did not differ significantly amongst groups, although prosthodontists asked significantly more questions in the ,clinical and radiographic information' category than GPs (P = 0·0001) and interns (P = 0·003). The relationship between a prescribed treatment and questions asked was tested by dichotomizing all recommendations into ,possible' or ,not possible' based on the authors' knowledge of the actual case history. There were no significant differences amongst the groups in the frequency of prescribing ,possible' treatment (Pearson chi-square 0·083 and 0·108 for upper and lower spaces, respectively), but those who prescribed ,possible' treatment asked significantly more questions in the ,clinical and radiographic information' category, specifically about bone adequacy in the edentulous areas: upper jaw (P = 0·0001) and lower jaw (P = 0·003). It may be concluded that prosthodontists generally opted for more ,possible' treatments, as well as seeking items of information that seemed to improve the chance of making recommendations that conformed to the actual case characteristics. [source]


Treatment with removable partial dentures: a longitudinal study.

JOURNAL OF ORAL REHABILITATION, Issue 5 2003
Part II
summary The aim of this study was to evaluate the effectiveness of an oral rehabilitation by removable partial denture (RPD). Between 1983 and 1994, 629 patients were provided with an RPD at the Dental School of the Université catholique de Louvain. All the RPDs were constructed with a cobalt,chromium framework. All the treatments were provided by dental students under the supervision of clinical instructors. At recall time (1998,2000), 269 patients could not be reached neither by telephone nor by mail and 27 had died. Consequently, 333 patients were called for clinical examination and 254 of these (76·3%) actually attended. For a total of 292 RPDs checked 1893 persistent teeth were listed, with 804 serving as abutments; more than half (57·6%) of these were crowned, for which 51 debondings were recorded. For the period of observation we listed 79 abutments lost (37 at the upper jaw and 42 at the lower jaw), i.e. 9·8% of the total number of abutments. No relation could be established between the type of the abutments (natural or crowned teeth) and the losses observed (Test of Mantel-Haenszel: P=0·9496). In the upper jaw, the percentage of abutments lost was significantly higher in the presence of free-end edentulous areas as compared with bounded edentulous areas (Test of Mantel-Haenszel: P=0·0002); this difference does not appear for the lower jaws (P=0·9558). If we deduct the 25 abutments related with the 11 non-worn RPDs and the 79 abutments lost, no change becomes apparent for 92·2% of the maxillary abutments and for 85·8% of the mandibular abutments. For the 1089 other teeth, we observed the loss of 40 teeth and the appearance of caries or new fillings for 95 teeth. The fractures of cast clasps represent 3·4%. [source]


ICK Classification System for Partially Edentulous Arches

JOURNAL OF PROSTHODONTICS, Issue 6 2008
Sulieman S. Al-Johany BDS
Abstract Several methods of classification of partially edentulous arches have been proposed and are in use. The most familiar classifications are those originally proposed by Kennedy, Cummer, and Bailyn. None of these classification systems include implants, simply because most of them were proposed before implants became widely accepted. At this time, there is no classification system for partially edentulous arches incorporating implants placed or to be placed in the edentulous spaces for a removable partial denture (RPD). This article proposes a simple classification system for partially edentulous arches with implants based on the Kennedy classification system, with modification, to be used for RPDs. It incorporates the number and positions of implants placed or to be placed in the edentulous areas. A different name, Implant-Corrected Kennedy (ICK) Classification System, is given to the new classification system to be differentiated from other partially edentulous arch classification systems. [source]


Ramus or Chin Grafts for Maxillary Sinus Inlay and Local Onlay Augmentation: Comparison of Donor Site Morbidity and Complications

CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 3 2003
Jaime Clavero DDS
ABSTRACT Background: The placement of endosseous implants in edentulous areas is frequently limited by inadequate bone volume of the residual ridge. Local bone grafts from the mandible are a convenient source of autogenous bone for alveolar reconstruction prior to implant placement. Purpose: The aim of the present study was to document and compare the morbidity and the frequency of complications occurring at two intraoral donor sites: the mandibular symphysis and the mandibular ramus. Material and Methods: This study reviewed 53 consecutively treated patients:29 with autogenous bone grafts from the mandibular symphysis and 24 with mandibular ramus bone grafts. Each patient received a questionnaire 18 months after surgery regarding problems that may have occurred during the postoperative period. Results: In the patients in whom bone was harvested from the mandibular ramus, there were fewer postoperative symptoms immediately after the operation than with mandibular symphysis harvesting. Twenty-two of the 29 patients with symphysis grafts experienced decreased sensitivity in the skin innervated by the mental nerve 1 month after the operation. Five of the 24 patients with ramus grafts experienced decreased sensitivity in the vestibular mucosa corresponding to the innervation of the buccal nerve. Eighteen months after the surgery, 15 of the 29 patients in the symphysis group still had some decreased sensitivity and presented with permanent altered sensation. Only one of the patients grafted from the mandibular ramus presented with permanent altered sensation in the posterior vestibular area. No major complication occurred in the donor sites in any of the 53 patients. Conclusion: The results of this study favored the use of the ascending mandibular ramus as an intraoral donor site for bone grafting. [source]


Effect of conical configuration of fixture on the maintenance of marginal bone level: preliminary results at 1 year of function

CLINICAL ORAL IMPLANTS RESEARCH, Issue 4 2010
Jung-Joo Kim
Abstract Objectives: To evaluate and to compare the effect of the conical neck design on marginal bone loss around the fixtures, when both implants were provided with micro-threads to the top of the fixture. Materials and methods: Two types of implant, one with a straight shape (S) and the other with a conical neck design (C) provided with a retentive element to the top of the fixture, were placed adjacent to each other in the partially edentulous areas of 12 patients. Bone loss around each implant was analyzed after 1 year of functional loading. The bone losses after loading were compared using Wilcoxon's signed-rank test. Results: The mean marginal bone losses (S, 0.05±0.09 mm; C, 0.07±0.14 mm) were not statistically significant between the two groups (P=0.578). Conclusions: There was no significant difference between conical and straight neck implants in terms of marginal bone loss after 1 year of loading. To cite this article: Kim J-J, Lee D-W, Kim C-K, Park K-H, Moon I-S. Effect of conical configuration of fixture on the maintenance of marginal bone level: preliminary results at 1 year of function. Clin. Oral Impl. Res. 21, 2010; 439,444 doi: 10.1111/j.1600-0501.2009.01871.x [source]


Orthodontic load on short maxillary implants with reduced sink depth: an experimental study

CLINICAL ORAL IMPLANTS RESEARCH, Issue 10 2008
H. Wehrbein
Abstract Objective: The aim of this study was to investigate experimentally the positional stability and histomorphometric findings of length-reduced temporary anchorage devices (Orthosystem®, length: 4 mm) with reduced sink depth. Material and methods: For this purpose, four maxillary pre-molars (2P2, 3P3) were extracted from each of four foxhounds. After a 16-week alveolar healing period, 16 implants (four per dog) were inserted into the edentulous areas. Four implants (one per dog) were placed simultaneously in the mid-palatal area. The implants were intentionally submerged to about three-quarters of their length. After a 10-week unloaded implant healing period, the implants in the P3 areas and the palate were loaded (test implants) by means of transpalatal bars fixed on the implants in the P3 areas and Sentalloy traction springs (,2 N continuous force) inserted mid-sagittally between palatal implants and bars (force application period: 24 weeks). The implants in the P2 areas served as controls. Results: Clinical measurements and histological evaluation revealed positional stability of the loaded fixtures. Alveolar control implants (ACI) were inserted to a mean depth of 3.2 mm, alveolar test implants (ATI) to 3.3 mm and palatal test implants (PTI) to 2.6 mm. The mean direct bone contact percentage values were 71.3% (ACI), 79.6% (ATI) and 72.2% (PTI). Conclusion: These results suggest that, probably due to the relatively high percentage of bone contact with implant surface, only 3 mm of intrabony implant length is sufficient to retain positional stability during long-term orthodontic loading. [source]