Stabilization splint treatment on complete denture--two reported cases.

The pre-prosthetic treatments of two female patients with osteoarthritis of the temporomandibular joints were presented in this paper. In the first case report, an 83-year-old patient wore complete dentures (CDs) for 30 years. The second patient (71 years of age) wore a three-year-old upper CD and a lower removable partial denture with a two-unit fixed dental prosthesis. Pain was successfully eliminated by the stabilization splint on the upper CD. Magnetic resonance imaging was used to confirm the diagnosis and clinical follow-up of the splint treatment.

Suggested guidelines for basic dental education in Europe.

With the enlargement of the European Community, a great effort was done. In order to abolish the inequalities that exists in the provision of oral health education and Oral healthcare delivery between Eastern and Western Europe. On the other hand, each day more emphasis is placed on the basic competencies and abilities gained during basic dental education due to internal and external driving forces. The differences between the systems are often very important prominent and seem to depend mainly on the national institutions or the government policy. Therefore there is a major responsibility for the profession in helping to integrate the dental practitioners in an updated approach. As a similar basic dental education will progressively been developed, the Continuing Education could become more complex. For this purpose, following a basic dental education complying with the current needs and demands, a more adapted Continuing Education program must be elaborated and promoted.

Curriculum structure: principles and strategy.

This report provides general guidelines for the structure of a curriculum, followed by specific advice on the principles of learning and teaching, the process of restructuring and change leadership and management. It provides examples of several educational philosophies, including vertical and horizontal integration. It discusses the use of competence, learning outcomes, level of degree and assessment and provides a number of recommendations. It does not seek to be prescriptive of time allocation to disciplines within a curriculum. Although this report has been written primarily for those who will develop an undergraduate curriculum, the information may be sufficiently generic to apply to the recent development in graduate entry ('shortened dental' or 'accelerated') courses and to postgraduate degree planning and higher education certificate or diploma courses for other dental care professionals (auxiliaries). The report may have a European bias as progress is made to converge and enhance educational standards in 29 countries with different educational approaches - a microcosm of global collaboration.

A survey of treatment outcomes with removable partial dentures.

The patient's satisfaction with removable partial denture (RPD) therapy has become an increasingly important factor in prosthetic treatment. This study examined patients' satisfaction with RPDs in relation to some socio-economic variables, patients' habits of wearing and cleaning RPDs, comfort of wearing RPDs and different RPDs characteristics. A questionnaire was devised for the purpose. Two hundred and five patients were required to assess satisfaction with RPDs. They graded RPDs, depending on the level of satisfaction, on scale ranging from 1 to 5. A dentist determined Kennedy classification, material and denture support, denture base shape, number of missing teeth and evaluated denture construction. Majority of the patients were satisfied with the prosthesis. The patients of a higher education level gave lower grades (P < 0.05) to aesthetics of maxillary RPDs. Almost half of the patients were wearing RPDs during the day. Most of the patients cleaned RPDs three times a day. A significant difference was found between the patients' grades for comfort of wearing mandibular RPDs and number of missing teeth and between hygiene of mandibular RPDs and habits of cleaning them. Majority of the patients treated with RPDs were satisfied with the prosthesis. Dissatisfaction was related to mastication, esthetics, number of missing teeth and maintenance of oral hygiene.

Bite force in subjects with complete dentition.

Bite force is the condition, expression and measure of the masticatory function. The purpose of this study was to examine, by means of a newly constructed electronic gnathodynamometer, the values of maximal bite forces in subjects with complete dentition, the time in which they express 50% and 75% respectively of the total forces value, and the shape of the bite curve during testing. The obtained data was statistically analyzed with respect to gender and age. Analysis of the variance confirmed the finding that there was no statistically significant correlation between the values of forces and subjects' age, but there was a statistically significant difference between males and females in the values of the bite forces in the front segment, as well as between the values of the force on anterior and posterior teeth. The correlation between the time T1 posterior right and T1 posterior left, and between T1 and T2 for anterior teeth are statistically significant. Analysis of the bite curves suggests that males "bite" shorter than females with a sharper peak of the curve. Numerical values and bite curves should be a diagnostic factor in the further follow-up of subjects or in the choice of prosthodontic therapy.

Association of horizontal and vertical overlap with prevalence of temporomandibular disorders.

The aim of the study was to evaluate the relationship between horizontal (HO) and vertical overlap (VO) and prevalence of temporomandibular disorders (TMD) in a non-patient population. Out of the total number of subjects (230), 65.7% subjects were classified as asymptomatic, 5.7% subjects had muscle disorders (MD) (myalgia), 9.1% subjects had disc displacement with reduction (DDR), while 19.6% subjects had disc displacement with reduction associated with muscle disorder (DDR + MD) (myalgia). The HO equal to or greater than 5 mm was significantly more prevalent in the symptomatic patients (MD, DDR, DDR + MD) than in the asymptomatic group (P < 0.001). The VO equal to or > 5 mm also demonstrated statistically significant difference (P < 0.006) between the symptomatic (suffering from DDR, and DDR + MD) and asymptomatic subjects. Conclusion of the study is that the HO and VO equal to or > 5 mm was more present in the group of subjects with diagnosis of a TMD (DDR and MD), what distinguishes this group from the group of asymptomatic subjects.

Relationship between the face and the tooth form.

The aim of this study was to re-examine Leon Williams geometric theory and to find the degree of correspondence between the face and the tooth form in the population of Zenica, Bosnia and Herzegovina. Two thousand individuals with intact frontal teeth, in age between 17 and 24 years, were measured for 3 horizontal distances on the face: temporal width (Ft-Ft), zygomatic width (Zyg-Zyg) and gonial width (Go-Go) and for 3 horizontal distances on the both upper incisors: cervical width (CW), contact point width (CPW) and incisal width (IW). The length of the face (Tr-Gn) as well as the length of the central maxillary incisors were also measured. The results revealed: 1. Men had significantly larger dimensions for all facial and tooth dimensions (p < 0.05) than women, except for the cervical tooth width (p > 0.05); the left and the right central incisors were of identical dimensions and forms (p > 0.05). 2. The width of upper central incisors were smaller approximately 1.5 mm than in west Europeans. 3. Upon the relation between the 3 horizontal dimensions measured on the face and upper maxillary incisor, 11 facial forms and 10 upper central tooth forms could be recognised in the study population, but 98% of the population had only 3 tooth and face forms. Face shapes: oval face--83.3%, square-tapered face--9.2% and tapered face--7%; tooth forms: tapered-square incisor--53%, oval incisor--30%, tapered incisor--16%. 4. Reversed and enlarged tooth form was in line associated with the facial form in only 30%, while the most common combination was of the oval face form and the tapered-square central incisor (45%). 5. These results disapprove William's theory and may be helpful for the choice of artificial teeth in complete denture construction and the dental industry.

The patient's and the therapist's evaluation of bridges of different materials and age.

The aim of this study was to find out patients' satisfaction with their bridges made of different materials (metal-ceramics, Au/resin, Ag-Pd/resin). One hundred and sixty four patients were examined at the Dental School, University of Zagreb, Croatia. They assessed their bridges--the overall quality, aesthetics, speech, chewing and the health of the gingiva by the scale from 1-5. The same categories were also assessed by a trained prosthodontist. The majority of the patients was really satisfied and gave the highest grades (quality, aesthetics, speech, etc.) and therefore the results were skewed and asymmetrical towards the biggest scores (biggest grades). The best gingival health was evaluated by the group of patients with ceramic crowns and bridges (p < 0.05) and the worst by the patients with Ag-Pd bridges. Speech was scored higher for the lateral than for the frontal bridges. Patients evaluated the health of the tissue surrounding their bridges, overall quality of fixed prosthodontic appliance and aesthetics with significantly higher scores than the prosthodontist (p < 0.01). The results point at a difference between the patient's and the therapist's evaluations and to the patient's insufficient care about the gingiva around the bridge abutments.

The effect of tooth loss on the TM-joint articular eminence inclination.

The inclination between the posterior wall of the articular eminence and the referential plane (Frankfurt line) was measured on 137 dry skull specimens (78 with complete dental arches and 59 edentulous). Both left and right joints were measured using direct craniometric method. The results were compared with respect to the loss of teeth, side and sex. A large range of measured values of the eminence inclination shows great individual differences, so that the mean values can have only orientational significance. The mean value of eminence inclination for all measured specimens was 61.9 angular degree. The difference between the two groups established upon dental status is very small and without any statistical significance (P > 0.05). The right joint shows a slightly steeper eminence inclination compared to the left one, but without any statistical significance (P > 0.05). Asymmetry between the right and left joint appears almost as a rule, while maximum measured differences reach up to 33 degrees, with mean absolute difference of 6.9 degrees. The group of edentulous specimens shows a greater symmetry and less differences between the left and right joint, which indicates that different bimechanical conditions in the joint, due to tooth loss might lead to remodellation of the articular eminence. The eminence inclination was significantly steeper in male specimens in all subgroups (P < 0.001), which confirms sexual dimorphism.

Bond strengths of two dental bonding systems.

A new bonding system named Kevloc has been introduced. It is based on acrylization of the metal surface with the goal of preventing the occurrence of a marginal gap between the metal and the resin. The purpose of this investigation was to determine the values of the shear bond strength achieved using the Kevloc technique on Ag-Pd (Auropal SE) and Co-Cr (Basil S) alloys and to compare them with those obtained with the OVS technique. The shear bond strengths were measured with the Smitz-Schulmayer shear test in a universal testing machine for polymer materials. A microscope image analyzer was used to measure the thickness of bonding layers and to reveal the possible occurrence of the marginal gap with both techniques. No marginal gap was detected with either technique. Kevloc provided better results than OVS only in a group of specimens tested after polymerization. Immersion in water and thermocycling reduced the initially high bond strength values of Kevloc specimens, whereas the bond strength values of OVS specimens remained unchanged regardless of which aging treatment was used. Microscopic examination did not reveal the existence of the marginal gap for either bonding system. According to the results obtained, it can be concluded that the Kevloc bonding system does not provide better shearing bond strength than the OVS bonding system.

Tooth loss and the condition of the prosthodontic appliances in a group of elderly home residents.

The study assessed the number of missing teeth, the state of the existing prosthodontic appliances and the need for their replacement. Dental status and anamnesis were taken on a group of 120 elderly home residents by trained examiners. Prosthodontic appliances were evaluated according to the Karlsson's index for the crowns and bridges, and according to the modified Nevalainen et al. index for the evaluation of the complete dentures, as well as the need for prosthetic treatment. The most persistent teeth in both jaws were lower canines, while the most commonly missing teeth were lower first molars. On average, the crowns were older and in poorer condition than the bridges. Lower complete dentures had better stability but were also less retentive in comparison with the upper complete dentures. More than 82% of the subjects were in need of either fixed, removable or combined prosthodontic treatment. The high prevalence of needs for prosthodontic treatment pointed to the requirement for frequent dental check ups within elderly home residents in order to better identify and meet their dental needs.

Terminal hinge axis--Hobo point--Frankfurt horizontal relations.

Aim of this investigation was to determine the spatial relations of the terminal hinge axis of the temporomandibular joints toward Frankfurt horizontal. The sample consisted of 50 examinees. Terminal hinge axis was located, using Lauritzen's technique, on the left side of face for each examinee. Arbitrary point, as proposed by Sumiya Hobo, was measured and point Orbital was defined by palpation. On designated points steel pellets 0.25 mm in diameter were stocked. Lathero--latheral cephalogram was obtained for each examinee. Cephalograms were traced down on a transparent foil and points Orbital, THA--terminal hinge axis, Hobo and Porion--as the uppermost point of the metal ear rod of the cephalostat, were designated. Connecting points Orbital and Porion, Frankfurt horizontal was defined, and shortest distance toward points THA and Hobo, as well as between them were measured. Lines parallel and perpendicular to Frankfurt horizontal were drawn through point THA. In a co-ordinate system defined in such a way, upper left quadrant was first, upper right second, lower right third, and lower left was fourth. Observation was made in which quadrant Hobo point was located. Measured values were statistically evaluated. Results revealed that Hobo point is located in first quadrant in 5 cases, in second in 7, third quadrant in 18, and in fourth in 20 cases. That means that Hobo point is located lower to the THA point in majority of our population. Points THA and Hobo were not identical in any case. Mean values of variables showed that investigated points were inferior to the FH. Measures of variability revealed great variability of both points toward FH, as well as for their mutual distance. It could be pointed out that THA point should be defined kinematically during prosthodontic procedures, and that orientation in articulator's space should not be according to the FH.

Vomer as relevant factor in the mastication forces transmission system.

In the region of the posterior segment of bony palate and nasal cavities in both sides, the following three bones come together: the upper jaw, the palatal and the sphenoid bones. The perpendicular upper palate lamina laterally leans on the corpus of the upper jaw and on the wing process of the sphenoid bone. It is the posterior bony transmission system that has been selected as a separate study entity, which is otherwise a functionally inseparable part of the overall system of trajectories of mastication forces. It is a supporting element that begins at the dental alveolus of the wisdom tooth, ascends along the tuber maxillae and by the wing process of the sphenoid bone transmits the mastication load to the body of the sphenoid bone, i.e. into the mid-portion of the neurocranial base. By observing the characteristics of the vomer and measurement of distances between its morphological markings, or craniometric landmarks, together with its fitting into the harmonic analysis of face and head, the essential role of vomer has been established in regard to the trajectory system of mastication forces which has enabled us to create the basis for further biomechanical research of this phenomenon using photoelasticimetric procedures.

Prosthetic rehabilitation of a warfare facial trauma.

This case report presents the prosthetic treatment of a warfare facial trauma patient with the aim of providing satisfactory function, esthetics, and alleviation of deformities. Veneer crowns with rests, root coping, and metal-base partial prostheses were used for the patient therapy and treatment.

Bond strengths of silicoated and acrylic resin bonding systems to metal.

STATEMENT OF PROBLEM: The Kevloc bonding system is based on the bond of acrylic resin with the metal surface, in contrast to the Silicoater system, which covers the metal surface with a SiOx-C layer. Bonding prevents the occurrence of the marginal gap between the metal and the resin, which causes weaker bond strengths and discoloration. PURPOSE: This investigation examined the bond strength values achieved by using the Kevloc technique on Ag-Pd and Co-Cr alloys, and compared them with those obtained by the Silicoater technique. After artificial aging, shear testing of the specimens was performed. MATERIAL AND METHODS: A microscope image analyzer measured the thickness of bonding layers to reveal any marginal gap. RESULTS: No marginal gap was noticed for either technique. The Kevloc technique provided better results than Silicoater regardless of alloy used. Immersion in water (7.64 to 8. 05 MPa) and thermocycling (6.12 to 6.95 MPa) reduced the initial bond strength values (12.52 to 12.94 MPa), but the breakdown occurred between the opaque layers or between the opaque and the resin, thus giving a cohesive type of failure. CONCLUSION: The dental alloy used did not affect bond strengths and artificial aging caused reduction in bond strengths. The Kevloc bonding system exhibited higher bond strengths than Silicoater, but the marginal gap was not seen for either bonding system.

The fatigue strength of the interface between Ag-Pd alloy and hydrothermal ceramic.

OBJECTIVE: The purpose of this paper was to investigate the fatigue strength of a hydrothermal ceramic fused to Ag-Pd alloy. This study compared the values with those of other metal-ceramic systems previously reported by other authors. METHODS: This investigation was performed on 48 specimens made of Ag-Pd alloy frames (45 x 12 x 4 mm) on which the hydrothermal ceramic was fused (25 x 12 x 2 gmm). The specimens were divided into two groups. The first group of specimens was dynamically loaded immediately after casting and fusing, while the other group of specimens was thermocycled (1000 times at 0 degree C and 55 degrees C) before dynamic loading. The dynamic loading tests were carried out by using a modified three-point load method in a universal testing machine. RESULTS: The determined dynamic loading limit was up to 550 N for thermocycled, and up to 850 N for non-thermocycled specimens. These results are very respectable in comparison with other metal-ceramics. A statistically significant difference between maximal dynamic forces and number of loading cycles for thermocycled and non-thermocycled samples was determined. SIGNIFICANCE: From the data obtained in this study and current literature profiles, it is concluded that the tested metal-ceramic system is more durable than other metal-ceramic systems.

Evaluation of the precision of dimensional measurements of the mandible on panoramic radiographs.

The purpose of this study was to evaluate the precision of dimensional measurements of the mandible on orthopantomographic images and thus to evaluate their dimensional reliability. Different distances denoted by metal markers were measured on 25 dry mandibles. The same mandibles were then positioned in an orthopantomographic machine, and radiographic images of them were made. Measurements of the same distances were made on the panoramic images and then compared with the results of the measurements on the dry mandibles. All results were statistically analyzed. The results showed significant difference between the magnification factor listed by the manufacturer and calculated magnification factors, the latter being closer to 1.00. The study also showed that linear measurements made on only one side of the panoramic image of a mandible were very close to the actual dimensions of the dry mandible, whereas measurements that extended across the midline of the mandible were greatly enlarged because of large magnification factors; therefore, such measurements should not be made.

Assessment of position of foramen mandibulae in recent adult population.

Accurate knowledge about the morphology and topography of foramen mandibulae is of great practical importance in anaesthesia of inferior alveolar nerve. A certain number of skeletotopical relations may be used as valuable orientation points. Because of the controversies about these marking points it has been decided to perform measurements on a large sample of macerated mandibulae that are significant to location and shape of foramen mandibulae (FM) and lingula in relation to the surrounding orientation points. The measurements were taken in antero-posterior and infra-superior directions. In AP direction the distance between PRR and FM was measured; the obtained sample average was 15.03 at variability of Qv 12.18%; ARR-FM distance had the average value of 17.52 at Qv of 50%; the CT-FM distance had the average of 14.81 at Qv of 8.17%. In infra-superior direction the following measurements were made: AM-FM with the average of 21.10 at Qv of 13.98%; IM-IF with the average of 25.19 at Qv of 16.18%; PCO-FM with the average of 44.17 at Qv of 10.48%; and PCR-FM with the average of 42.79 at Qv of 10.87%. Extreme heterogeneity was noticed in the measurements of lingula. In the antero-posterior plane the FM is located in the middle of the CT-PRR distance, i.e., in measurements in which the external oblique line was used as anterior point, FM was located at the juncture of two anterior thirds and the posterior third of ramus mandibulae. In infra-superior direction the lowest FM point was closer to AM than to IM, indicating a somewhat lower position of FM. The mean value of FM depth was 4.31 and the most commonly found shape of the foramen was that of the elongated type (45%). The lingula was prominent, although unevenly, in 51% of study samples.

Estimation of referent cephalometric parameters in dental prosthetics.

Estimation of the inclination of the occlusal plane and its spatial orientation during the insertion of plaster casts in the articulators space, and control during the clinical phase of the prosthetic work, is one of the key problems in dental prosthetics. The aim of this investigation was to compare the relations of the basic roentgencephalometric parameters applied and to determine their reliability. Five angular variables were analysed: OP-MdP, OP-PP, OP-CP, OP-FP and OP-SNP, on a sample of 86 radiographs of subjects with almost normal occlusion by applying basic statistical parameters and the correlation's analysis. The results gave mean values of the investigated variables with estimation of their variability and level of mutual correlation, which can be used when determining individual inclination of the occlusal plane. Parameters FP and SNP showed significant stability and reliability which can be successfully applied in prosthodontics.

Modification of the angle of the lower third of the face.

Determination of vertical dimension of occlusion by roentgencephalometric method, with the help of the angle of the lower third of the face, has been described in literature. The aim of this study was to modify the angle of the lower third of the face and correlate its determination with reference planes for orientation of casts in the articulators space, to determine mean value and measures of variability of the modified angle in a random sample, and the possibility to use this angle as a control value for establishing the height of the lower third of the face. On a sample of 131 roentgenograms in L-L projection, with teeth in maximal intercuspation, points: N, IS47, THA, SNA, SNP, Xi and Pg were traced down. By the use of this points the angle of the lower third of the face (angle K) was constructed. The values of the angle were measured and statistically analyzed. Mean value of the angle was 48.5 degrees, with standard deviation of 4.41 and coefficient of variation 9.09%. The investigated angle can serve as a control value for determination of intermaxillary relationships and should not be accepted as an strict norm.