Normal Dentition Research Articles

Chama pulchella (Bivalvia : Heterodonta) with Transposed Shell and Normal Dentition

Chama pulchella (Bivalvia : Heterodonta) with Transposed Shell and Normal Dentition

A Study on Normal Primary Dentition Classified by the Standard Qualification of Occlusion

A Study on Normal Primary Dentition Classified by the Standard Qualification of Occlusion

Pediatric Dental Rehabilitation Procedures in the OR

Children with significant baby bottle tooth decay and children who are challenged by significant physical and emotional limitations are candidates for dental rehabilitaion procedures with general anesthesia. Rehabilitation of children's primary teeth is important to prevent pain, infection, and tooth loss. To provide skilled care for children undergoing dental rehabilitation procedures, perioperative nurses must understand normal dentition, tooth anatomy, and caries prevention and formation and be able to meet children's developmental and emotional needs. Perioperative nurses also must collaborate with dentists to maintain appropriate supply inventories that are unique to dental rehabilitation procedures.

Wertigkeit der zahnärztlichen Behandlung bei der interdisziplinären Betreuung eines Kindes mit Epidermolysis bullosa dystrophica hereditaria (Hallopeau-Siemens)

Severe dystrophic epidermolysis bullosa with oral involvement often leads to dental destruction and restricted food intake, resulting in malnutrition and maldevelopment. The patients become handicapped and have a poor prognosis. We report on a now 13-year-old Turkish child with normal secondary dentition who had severely damaged primary dentition. The teeth were treated surgically and then by continuous dental hygiene measures over the next 7 years. This care also resulted in an improvement in the nutritional state, associated anemia and the incidence of skin infections. Although cutaneous blistering and scarring has been progressive, with resulting mutilation of the fingers, the child is socially well adjusted in school and family. Its clinical course demonstrates that the fate of patients with severe dystrophic epidermolysis bullosa can be improved through multidisciplinary management.

Mirror‐image dental fusion and discordance in monozygotic twins

A pair of monozygotic twins had similar but not identical dental anomalies. One twin had fusion of deciduous mandibular lateral incisor and canine on the left, with normal dentition on the right; the co-twin had right mandibular incisor/canine fusion, with aplasia of the lateral incisor on the left. These findings are discussed in the context of the related phenomena of situs inversus, mirror-imaging in twins, and gradients of severity of anomalies in the four copies of the mandibular developmental dental field.

8 総義歯装着者および正常有歯顎者の咀嚼運動経路に関する研究 (第433回 大阪歯科学会例会)

8 総義歯装着者および正常有歯顎者の咀嚼運動経路に関する研究 (第433回 大阪歯科学会例会)

Analysis of Chewing Path in People with Complete Dentures and with Normal Dentition

Analysis of Chewing Path in People with Complete Dentures and with Normal Dentition

臼歯離開量の予備的計測

Disocclusion is a common sense in today's prosthetic dentistry. The amount of disocclusion based on quantitative data is not known. Impressions of 25 male subjects with normal dentition and free of TMD were taken using silicone bite material during protrusive and lateral movements. Cutting them through mesio-buccal cusp tip of the lower first molar, distances between them and occlusal surfaces of the opposing teeth, were measured.The results showed that the average amounts of disocclusion are about 1 mm during protrusive movement and on nonworking side during lateral movement, and about 0.5mm on working side during lateral movement. Standard deviations were 0.3mm-0.6mm.

Marginal bone level in the normal primary dentition.

The aim of the present study was to establish the normal range for the radiographic distance between the cemento-enamel junction (CEJ) and the marginal bone level (MBL) in the primary dentition, and to relate this distance to various physiological and pathological factors. 128 children at the ages 7, 8 and 9 years took part in the study. Clinical and radiographic examinations of the mesial and distal surfaces of all primary molars and the distal surface of the primary canines were performed. The clinical examination included measurements of the amounts of plaque, bleeding on probing, probing depth and probing attachment loss. In addition, increased mobility of the primary teeth and stage of eruption of the neighbouring permanent teeth were recorded. The radiographic examination included measurements of the CEJ-MBL distance and the remaining root length. Also, exfoliating teeth, presence of proximal dentin caries, restorations and calculus were recorded from the radiographs. Associations between various explanatory variables and the CEJ-MBL distance were tested with both a chi 2 test and a variance components analysis. The mean CEJ-MBL distance for all primary tooth surfaces was 1.0 mm. Individual surfaces displayed distances ranging from 0.0-4.0 mm. Of the variables tested for association with the CEJ-MBL distance, eruption of neighbouring permanent tooth and exfoliation of neighbouring primary tooth seemed to be associated with large CEJ-MBL distances. When surfaces with these characteristics were excluded, a CEJ-MBL range of 0.0-2.0 mm was obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Supraeruption of the unopposed maxillary first molar

Supraeruption of the maxillary first molar in the absence of the mandibular first molar was observed in subjects with both normal and pathologic periodontics. Both the migration of the gingival margin and the increase in the crown height were evaluated in terms of the length of time the antagonist tooth had been missing. Values obtained were compared with those of a reference group with complete normal dentitions. The results show that in the first years following the loss of the opposing tooth, supraeruption is mainly due to growth of the periodontium. Later, or in the case of periodontal pathosis, tooth movement beyond the occlusal plane is due principally to active eruption.

天然歯列こう合小面の傾斜角および面積に関する研究

The characteristics of occlusal facets are important criteria used in the functional assessment of the stomatognathic system. A new system of optically quantifying the facets using a graphic image-processor has been developed, which makes it possible to measure the area and the inclination angles of each facet in the frontal and sagittal sections. In this study, the occlusal facets were investigated in 5 cases with normal dentition concerning the inclinations, areas, locations and occlusal contacts. The facets which made contact with their opposing ones in the intercuspal and lateral occlusal positions were selectively analyzed. The frontal inclination angles of the facets increased or decreased according to their mesio-distal locations in the working-facet or balancing-facet series, respectively. The sagittal ones indicated that most of the facets on the lateral excursion belonged to either the mesial or distal slopes of the cusps in each case. The angles made by the upper and lower facets which made contact were greater in the lateral occlusal positions than in the intercuspal position. Most of the areas of the upper facets were larger than those of the lower ones, which fact was remarkable on the facets related to the occlusal contacts between the intercuspal position and the cusp-to-cusp positions of the canines.

成人正常者におけるこう頭かん合位および側方運動時のこう合状態に関する研究 第１編 立体的検索方法およびこう頭かん合位のこう合状態

成人正常者におけるこう頭かん合位および側方運動時のこう合状態に関する研究 第１編 立体的検索方法およびこう頭かん合位のこう合状態

成人正常者におけるこう頭かん合位および側方運動時のこう合状態に関する研究 第２編 側方運動時作業側のこう合状態

成人正常者におけるこう頭かん合位および側方運動時のこう合状態に関する研究 第２編 側方運動時作業側のこう合状態

Reaction of mastication to occlusal changes induced by correction of mandibular prognathism

Incisor-point masticatory movements of 22 patients were recorded before and after correction of mandibular prognathism. Chewing patterns and movement parameters were compared between preoperative and postoperative states and to corresponding quantities of 85 persons with normal dentitions. The prognathism patients most frequently revealed “chopping-type” patterns characterized by nearly vertical closing strokes, whereas mastication in the reference group was dominated by lateral grinding-type movements. There were no significant differences in the pattern distributions and parameter values between the preoperative and postoperative states. An individual assessment, considering random fluctuations of chewing behavior, showed that only five patients had changed their chewing mode possibly because of the treatment. Only a minor part of these changes could be directly related to the altered occlusion. It is concluded that the characteristic chewing mode of persons with mandibular prognathism does not interfere with the occlusal profile, and hence does not react to alterations.

Changes in maximum bite force related to extension of the head

The maximum bite force and position of the hyoid bone during natural and extended head posture were studied in 15 adults. All participants had normal occlusions and full dentitions. In addition, there were no signs or symptoms of craniomandibular disorders. The bite force was measured with a bite force sensor placed between the first molars. Six registrations of gradually increasing bite force up to a maximum were made with randomized natural and extended head postures. With one exception, the mean maximum bite force value was found to be higher for every subject with extended head posture compared to natural head posture. The sample mean was 271.6 Newton in natural head posture and 321.5 Newton with 20 degrees extension. With changed head posture, the cephalometric measurements pointed towards a changed position of the hyoid bone in relation to the mandible and pharyngeal airway. The cephalometric changes in the position of the hyoid bone could be due to a changed interplay between the elevator and depressor muscle groups. This was one factor which could have influenced the registered maximum bite force.

総義歯装着者のそしゃく機能評価に関する臨床的研究 正常有歯顎者と総義歯装着者のそしゃく運動の比較について

The purpose of this study was to comparatively study and elucidate the characteristics of masticatory function of the subjects with complete denture and those with normal natural dentition. The study were carried out on 20 subjects with normal natural dentition and 30 subjects with complete denture having clinically good prognosis. Masticatory movements were analyzed by electromyograph (EMG) and sirognathograph (SGG) when the subjects were chewing peanuts and kamaboko (boiled fish paste). The results were as follows: 1. The duration of chewing cycle, closing phase, occluding phase, and EMGs burst duration (especially after tooth contact) were significantly longer in the subjects with complete denture. 2. The maximum opening distance was significantly shorter, the maximum opening and closing velocity were significantly slower, in the subjects with complete denture. Further, the standard deviation of the coordinates of the sample points in the occluding phase was indisordered in the subjects with complete denture, and standard deviation of the coordinates of sample points in occluding phase were varied in complete denture wearers. 3. The frontal masticatory pattern tended to unstable and typical tear drop shape pattern was found in about 60% of the subjects with complete denture. 4. Different reactions to the test foods were observed in the subjects with normal natural dentition, while such was not noted in the cases of the subjects with normal natural dentition. These results was suggest that the masticatory function in the subjects with complete denture were obviously differ from those of normal natural dentition due to the difference in the sensory-motor-system.

実験的義歯床でのＤｅｎｔｕｒｅ ｐｌａｑｕｅ形成とＦｉｂｒｏｎｅｃｔｉｎの時間的関連性について

The main purpose of this study is to examine the process of denture plaque formation and relationships between denture plaque and fibronectin.Plasma fibronectin has been detected in dental pellicle and dental plaque, and the capacity of the cells to bind gram-positive or gram-negative bacteria was shown. Three types of experimental denture plate were set in oral cavities of subject with normal dentition, for 1, 3 and 6 days. Obtained samples were staining with FITC labeled anti-aerobic bacteria rabbit serum, FITC labeled anti-anaerobic rabbit serum and FITC labeled anti-Candida rabbit serum and each of them were stained with RITC labeled anti-fibronectin goat immunoglobulins. They were observed by fluorescence microscopy. Fibronectin was found on all kinds of experimental denture plate, and existed positions are mainly equal to adherence of aerobic bacteria, anaerobic bacteria and Candida albicans.This study shows that fibronectin is significantly related to the formation of denture pellicle and denture plaque. The results play an important role that fibronectin might be correlated to the initial formation of the denture plaque.

Occlusal tooth contacts in natural normal adult dentition in centric occlusion studied by photocclusion technique.

The inter- and intraexaminer reproducibility in the interpretation of the registrations of the photocclusion technique as well as the number of occlusal contacts and their intensity in natural normal dentition in centric occlusion were studied in 20 adults. No significant differences were found regarding the inter- and intraexaminer interpretations for both number and intensity of occlusal contacts. A mean number of 23.8 contacts per individual, an almost symmetric and balanced distribution of the contacts between left and right sides of the dentition, and an absence of any significant differences between female and male subjects characterized the normal natural dentition.

Long‐Term Preservation of Permanent Teeth in a Patient with Papillon‐Lefevre Syndrome Treated with Etretinate

Papillon-Lefèvre syndrome (PLS) is a rare autosomal recessive genodermatosis characterized by the association of palmoplantar keratoderma with severe periodontopathy resulting in premature loss of both deciduous and permanent dentition. We treated a patient with PLS with etretinate and followed him for 10 years. Treatment was started at age 9 years, soon after the eruption of secondary dentition. Healing of cutaneous and periodontal lesions was obtained in a few months and maintained during the four years of treatment. Six years after etretinate withdrawal the teeth are still free of periodontal disease and firmly anchored to the alveolar bone. Our case confirms that retinoid therapy can positively influence the development of normal dentition in PLS when it is started during the eruption of the permanent teeth, and suggests that this result can be maintained for a long time even after stopping therapy.

Distribution of occlusal contacts in maximum intercuspation

This study describes the use of the T-Scan system to record and analyze tooth contact data by calculating time moment statistics in the sagittal and transverse axes of the occlusal plane and reports the results of this method to analyze the occlusion of 93 normal subjects. Results confirm the findings of previous investigators and indicate that in a normal dentition there is a tendency for bilateral equality of the tooth contacts about the sagittal axis and that the center of effort for tooth contacts anteroposteriorly is located in the region of the first molar and is symmetrical bilaterally. Because of the rapid and accurate ability of the T-Scan system to identify the distribution of the tooth contacts, it shows great promise as a clinical diagnostic screening device for occlusion.