Arrangement Of Artificial Teeth Research Articles

Established prosthodontic rules confirmed in natural adolescent occlusion

Guidelines have been established for the arrangement of artificial teeth based on the curve of Wilson, the curve of Spee and the occlusal plate rule of Gysi. However, no scientific studies have been carried out to see whether these prosthodontic rules are actually present in natural teeth. This study was carried out on a selected sample of children and adolescents with natural dentitions using a 3D computer-aided measuring device to reevaluate these occlusal rules in order to establish whether occlusion with anterior protected articulation is the occlusal scheme of choice. The previously estblished prosthodontic rules were confirmed to be present in the complete natural dentitions of adolescents at completion of tooth eruption period and support their use as guiding principles in diagnosis and treatment.

Effect of denture fabrication and wear on closest speaking space and interocclusal distance during deglutition

The accuracy of assessing maxillomandibular relationships for trial bases and dentures using phonetic and swallowing methods has not been compared to that observed with definitive prostheses. Thus, there is no evidence to prove whether measurements obtained through such methods remain the same after adaptation to dentures. This study investigated changes in the closest speaking space, interocclusal rest space, and interocclusal distance during deglutition in edentulous patients during and after complete denture treatment. Eighteen edentulous subjects participated in this study and measurements were performed after 7 intervals of time: (1) with occlusion rims and record bases following creation of the maxillomandibular relationship record, (2) with trial dentures, (3) at insertion of definitive complete dentures, (4) 1 week, (5) 2 weeks, (6) 1 month, and (7) 3 months after insertion. Recordings of interocclusal distances were made with a mandibular kinesiograph. Closest speaking space was measured during the pronunciation of the word 'seis'. The distance between postural rest position and centric occlusion, or interocclusal rest space, was measured using a kinesiograph. Interocclusal distance during deglutition was tested by recording the closest mandibular position recorded during swallowing of 20 mL of water. Data were analyzed using repeated-measure ANOVA, followed by the Student-Newman-Keuls test (alpha=.05). A significant (P<.01) reduction in the mean closest speaking space was found when it was evaluated using occlusion rims and record bases (4.6 mm) compared with other stages (3.0 to 3.4 mm). No significant differences were found in mean interocclusal rest space and interocclusal distance during deglutition among the time periods evaluated. The presence of occlusion rims can influence mandibular position during pronunciation of the /s/ sound. The arrangement of artificial teeth changes the closest speaking space. However, rest position and deglutition were not affected, either during denture fabrication or short-term use.

咬合挙上を伴う補綴処置を行った多数歯欠如症例

A 53-year-old male presented with the chief complaint of masticatory disturbance caused by many teeth missing in the upper and lower jaws. There was extensive attrition on incisors and canines which only had occlusal contact, so the case was diagnosed as overclosure. To improve masticatory disturbance as the chief complaint, removable partial dentures were made after treating the abutment teeth. An adequate vertical dimension was planned in order to restore the worn teeth on the cast, and to arrange artificial teeth in the edentulous area. An anterior teeth core made as an inter-occlusal record was useful and the arrangement of artificial teeth in the edentulous area useful for estimating the adequate vertical dimension. It is important to diagnose an adequate vertical dimension by creating acast of the original tooth form in the case of prosthetic treatment of severely worn teeth.

治療用義歯によるデンチャースペースの回復

The number of patients with edentulous jaw suffering from the functional disturbance along with mandible deviation due to alveolar ridge absorption (alveolar bone, gnathic bone) is increasing. Many of these patients tend to be loaded with a type of low (infracclusion) and tiny (lack of denture space) complete denture with irregular occlusal plane (angle and arrangement position) - (negative cycle of conformation and function) .In this regard, the instability of denture (insufficiency of retention and support), the occurrence of mandible deviation (deviation of temporomandibular joint and muscle tonus) and the disagreement of oral peripheral muscle and tongue) were observed. Thus, for patients having functional disturbance generated by the disorder of functional occlusion system related to the combination of muscle-temporomandibular joint?occlusion, we must produce complete denture after providing them with toothless jaw treatment applying treatment denture, rather than producing complete denture only with impression taking and maxillomandibular registration- (from production of complete denture to toothless jaw treatment) .The conditions that curative denture should fulfill are as follows:1. Having retention (four types with impression+two types with curative denture's functional pressure=six types) and support (alveolar ridge load+load with circumoral muscle and tongue) (stability) ;2. Adequate occlusal plane (taking into consideration function and harmonizing with living organism) ;3. Denture space satisfying muscular retention and balance of occlusion (height x width=denture space) ;4. Compatibility to mucous membrane (taking into consideration masticatory mucous membrane, ratio of overlying mucosa and characteristics) ;5. Artificial tooth selection and arrangement attaching importance to the stability of denture and eating and swallowing functions;6. Stabilized mandibular position.Meeting the above conditions will ensure functional improvement in the course of morphological recovery. Further improvement of function should apparently complete the conformation leading to the reconstruction of stomatognathic function- (positive cycle of conformation and function) .I would like, on this occasion, to explain the recovery of denture space applying curative denture in toothless jaw treatment.

Finite element analysis of the effect of the bucco-lingual position of artificial posterior teeth under occlusal force on the denture supporting bone of the edentulous patient.

To improve the quality of the complete denture prosthesis, the bucco-lingual position of the artificial posterior teeth must be determined with consideration of the shape of the maxillary and mandibular residual ridge and the relationship between them. The arrangement of posterior artificial teeth should be considered not only for the denture stability but also for the avoidance of high pressure on the supporting structures. A two-dimensional finite element method program to investigate the statics for the contour of the complete denture and the residual ridge was developed. With this program, the effect of the bucco-lingual position of the artificial posterior teeth under occlusal force on the denture supporting bone could be investigated.

Arrangement of artificial teeth in the neutral zone after surgical reconstruction of the mandible: A clinical report

This clinical report describes the fabrication of a fixed partial denture, supported and retained by implants, for a patient with unfavorable tongue movement caused by movable grafted skin on the floor of the mouth after surgical reconstruction of the mandible. The neutral zone technique was used, and successful results were obtained. (J Prosthet Dent 2002;88:125-7.)

An assessment of the ability of dental undergraduates to choose artificial teeth which are appropriate for the age and sex of the denture wearer: a pilot study.

One of the main objectives in selecting and arranging artificial teeth is to produce prostheses which defy detection. With an appropriate degree of clinical experience and expertise it should be a relatively straightforward procedure to select a suitable artificial tooth mould. However, for the relatively inexperienced dental undergraduate it can be a challenging process. The aim of this study was to assess the ability of dental undergraduates to select artificial teeth which are appropriate for the age and sex of the denture wearer. One hundred and fifty dental undergraduates aged 18-35 were asked to complete a questionnaire to assess their attitudes towards artificial tooth selection and asked to correctly identify six artificial tooth arrangements according to age and sex. The results showed that a large percentage of dental undergraduates at Bristol experience difficulty in selecting artificial teeth which are appropriate for the age and sex of the denture wearer. There is a need for improved training and guidance on artificial tooth selection and arrangement.

An assessment of the ability of dental undergraduates to choose artificial teeth which are appropriate for the age and sex of the denture wearer: a pilot study

One of the main objectives in selecting and arranging artificial teeth is to produce prostheses which defy detection. With an appropriate degree of clinical experience and expertise it should be a relatively straightforward procedure to select a suitable artificial tooth mould. However, for the relatively inexperienced dental undergraduate it can be a challenging process. The aim of this study was to assess the ability of dental undergraduates to select artificial teeth which are appropriate for the age and sex of the denture wearer. One hundred and fifty dental undergraduates aged 18–35 were asked to complete a questionnaire to assess their attitudes towards artificial tooth selection and asked to correctly identify six artificial tooth arrangements according to age and sex. The results showed that a large percentage of dental undergraduates at Bristol experience difficulty in selecting artificial teeth which are appropriate for the age and sex of the denture wearer. There is a need for improved training and guidance on artificial tooth selection and arrangement.

Relationship between the stress distribution and the shape of the alveolar residual ridge – three‐dimensional behaviour of a lower complete denture

Purpose: For a complete denture to function effectively, the denture must be stabilized during mastication. The alveolar ridge has various forms, and we must choose the artificial tooth arrangement that is most suitable to the form of the alveolar ridge. The purpose of this study was twofold: (i) to examine the relationship between the alveolar ridge form and the stress distribution on the mucosa, and (ii) to model the contact condition between the denture base surface and mucosa. Materials and methods: In this study, the three‐dimensional finite element method was used for the analysis. Four types of alveolar ridge were prepared. As a loading condition, three load places were prepared: the mesial position, the central position and the distal position. We utilized the ‘contact option (MARC)’ to simulate the true behaviour of the denture. Results: We were able to model the contact condition by using the ‘contact option’. Maximum stresses were distributed on the alveolar ridge in which the absorption is severe. And, the distal load produced large compressive stresses on the inclined plane of posterior alveolar ridge in which alveolar form.

Relationship between the stress distribution and the shape of the alveolar residual ridge--three-dimensional behaviour of a lower complete denture.

For a complete denture to function effectively, the denture must be stabilized during mastication. The alveolar ridge has various forms, and we must choose the artificial tooth arrangement that is most suitable to the form of the alveolar ridge. The purpose of this study was twofold: (i) to examine the relationship between the alveolar ridge form and the stress distribution on the mucosa, and (ii) to model the contact condition between the denture base surface and mucosa. In this study, the three-dimensional finite element method was used for the analysis. Four types of alveolar ridge were prepared. As a loading condition, three load places were prepared: the mesial position, the central position and the distal position. We utilized the 'contact option (MARC)' to simulate the true behaviour of the denture. We were able to model the contact condition by using the 'contact option'. Maximum stresses were distributed on the alveolar ridge in which the absorption is severe. And, the distal load produced large compressive stresses on the inclined plane of posterior alveolar ridge in which alveolar form.

Trial anterior artificial tooth arrangement for an immediate denture patient: A clinical report

J Prosthet Dent 2000;84:260-3.

臼歯部人工歯排列に考慮を要した総義歯補綴の１症例 術後７年経過症例

臼歯部人工歯排列に考慮を要した総義歯補綴の１症例 術後７年経過症例

下顎片側遊離端欠損症例における垂直荷重時の義歯床の回転

In function, the movement of removable partial denture in various directions is caused by biting force or masticatory force. For free-end saddle denture, these movements are known to have a bad influence on abutment teeth or residual ridges.For denture retention and stability and for protecting supporting tissues, movement should be kept as small as possible.In this study, by focusing on the artificial teeth arrangement procedure which minimizes denture movements in function, it was attempted to establish a method of measuring lower unilateral denture base movement under loading and of analyzing it as rotation with a three-dimensional 6-degree comparator.The results were as follows: 1. An angle of denture base rotation on the horizontal plane (Yawing) tended to be smaller than that on the frontal plane (Rolling) and on the sagittal plane (Pitching). The loading position had little influence on the angle of Yawing. 2. Empirical equations, which express the angle of Rolling and Pitching, were obtained from the investigation of the relation between the denture base movement and the loading position in the frontal sections of the residual ridge. These results suggested that the position of artificial teeth on the residual ridge, which control the denture base movement, could be estimated by using these equations.

上下顎同時印象による総義歯の臨床

Swallowing is the most important movement in the oral cavity as an inret of nutrition essential to the maintenance of the human life. At that time, patients wearing full dentures due to edentulous jaw have comparable movements to those observed in the dentulous jaw. Namely, the tongue press its tip against the rugae of palate in the first stage of swallowing, and then gradually establishes contact between its back and the posterior portion of palate with pressure to transport the food into the pharynx. During this couse, the contact of the posterior portion of tongue with dentures plays an important role in stabilization of dentures.Strack has proposed that arrangement of artificial teeth in the same place as that of the natural dentition is the best way to maintain the stability of denture.In recent years, techniques of making dentures have been improved with the advancement of dental materials. I devised a method of simultaneously making impressions of upper and lower jaws using a injection device and a silicon impression material. I have routinely used this new system to make full dentures for clinical cases.On this occasion, registration of interocclusal relation, gothic arch tracing, simultaneoustaking of upper and lower impressions, and face bow transfer will be performed in front of you using patients, from the initial examination to the setting of full dentures.

Application of a three-dimensional reconstruction method to analysis of the residual ridge.

The purpose of this study was to develop a new method of analysing the shape of the residual ridge. The line of the residual ridge crest was regarded as the reference for artificial tooth arrangement and a method of determining it was evaluated. The shape of a plaster model was measured with a contact-type shape measurement system. The measurement data in each frontal section were interpolated by cubic splines. The points corresponding to the residual ridge crest were calculated and superimposed onto the image of the plaster model on a monitor screen of an image processor. Using these points and the image of the plaster model, the line of the residual ridge crest was marked on the plaster model. It was concluded that this method could be used to determine the line of the residual ridge crest on a plaster model.

Application of a three‐dimensional reconstruction method to analysis of the residual ridge

summary The purpose of this study was to develop a new method of analysing the shape of the residual ridge. The line of the residual ridge crest was regarded as the reference for artificial tooth arrangement and a method of determining it was evaluated. The shape of a plaster model was measured with a contact‐type shape measurement system. The measurement data in each frontal section were interpolated by cubic splines. The points corresponding to the residual ridge crest were calculated and superimposed onto the image of the plaster model on a monitor screen of an image processor. Using these points and the image of the plaster model, the line of the residual ridge crest was marked on the plaster model. It was concluded that this method could be used to determine the line of the residual ridge crest on a plaster model.

リモールディングに関する研究 動的適合試験材を用いた生理的人工歯排列基準

The proper relation of the muscle pressure surface form and surrounding tissue is of great importance. Physiological arrangement of artificial teeth using the trial fitness material and Remolding is a new technique to form the functional contour of the denture.In this study, five edentulous patients with different ridge resorption were selected, the extent of tongue space, comfort and function of the complete dentures constructed by the Remolding technique (R-denture) and conventional method (C-denture) were compared.The results were as follows:1. The tongue space of physiological teeth arrangement was significantly larger than that of posterior teeth which were set on the interalveolar ridge line.2. Three of 5 patients evaluated a definite superiority of chewing, speech, stability and inferiority of food accumulation with the R-denture.3. In selecting a set of dentures for regular use, all 5 patients preferred R-denture.4. The masticatory movements of R-denture was better balanced than that of C-denture in chewing rhythm.5. It is suggested from tomographic diagnosis that the triangle area drawn from the maxillary residual ridge crest and mandibular supporting bone is suitable criterion for the arrangement of artificial posterior teeth.

無歯顎の対向関係の診査・診断法 ３次元再構築法の利用

It is important to diagnose the maxillomandibular relation for the arrangement of artificial posterior teeth. In this study, a new method of diagnosis was developed. The contours of edentulous casts and three ball bearings and their impressions on the occlusion rims were measured by a noncontact type shape-measurement system. Using the measuring data of the casts which were interpolated by spline curves and the tentative plane of occlusion, anatomical alveolar crests were calculated. On frontal sections, the angle between the tentative plane of occlusion and the interalveolar ridge lines were calculated.The results of analysis, including anatomical alveolar crests of upper and lower casts and interalveolar ridge lines, were displayed on the CRT of a personal computer in occlusal, lateral and front views. As a result, it was suggested that this method was useful in the diagnosis of the maxillomandibular relation to edentulous casts.

A new guide for positioning of maxillary posterior denture teeth.

There is no definitive method for the arrangement of artificial teeth in complete denture construction. A new method is introduced whereby the maxillary posterior teeth have been set in approximate positions mediolaterally similar to their natural predecessors. The procedure is based on a constant relationship derived from the natural dentition. Its clinical application proved to be suitable for the arrangement of artificial teeth for complete dentures with minimal errors.

粘弾性解析による義歯床下組織の応力分布 第１報 人工歯の排列位置が義歯床下組織の応力分布に及ぼす影響

In complete denture fabrication, the stress concentration in the supporting structures should be avoid. Such stresses can produced pain during function or ulcerations of the supportingtissue. This study examined the effect of the arrangement of artificial teeth on the stress distributionsin the supporting structures under the denture. The denture with three different arrangementsof artificial teeth were simulated using a two dimensional viscoelastic finite element stress analysis.The results were as follows:1. The area of greatest stress concentration was mylohyoid region because the mandibulardenture rotated in that direction. The denture was supported on the lingual slope of the residualridge.2. As the position of the artificial teeth moved from lingual side to buccal side, the stressintensity at the high stress concentration area decreased and the stress distribution in the soft tisssueand bone became uniform.3. As compared with the results under the different loading condition, the displacement of thedenture in the lingual direction and the stress intensity at the mylohyoid region increased when theconcentrative vertical load applied at artificial teeth.