Maxillary

Distribution by Scientific Domains
Distribution within Medical Sciences

Terms modified by Maxillary

  • maxillary anterior tooth
  • maxillary arch
  • maxillary artery
  • maxillary canine
  • maxillary central incisor
  • maxillary complete denture
  • maxillary cyst
  • maxillary defect
  • maxillary denture
  • maxillary first molar
  • maxillary implant
  • maxillary incisor
  • maxillary lateral incisor
  • maxillary molar
  • maxillary overdenture
  • maxillary permanent incisor
  • maxillary premolar
  • maxillary right central incisor
  • maxillary sinus
  • maxillary sinus augmentation
  • maxillary sinus floor
  • maxillary sinus floor augmentation
  • maxillary sinus floor elevation surgery
  • maxillary sinuse
  • maxillary sinusitis
  • maxillary tooth

  • Selected Abstracts


    Root and canal morphology of maxillary first and second permanent molar teeth in a Ugandan population

    INTERNATIONAL ENDODONTIC JOURNAL, Issue 9 2007
    C. M. Rwenyonyi
    Abstract Aim, To investigate the root and canal morphology of permanent maxillary molar teeth from a Ugandan population. Methodology, Maxillary first (n = 221) and second molar (n = 221) teeth were collected from patients attending dental clinics in Kampala. Teeth were prepared using a clearing technique: the pulp chambers were accessed and the teeth placed consecutively into 5% sodium hypochlorite, 10% nitric acid, then methyl salicylate. Indian ink was injected into the pulp chambers to demonstrate the canal system. Results, In the first molars, 95.9% of the teeth had separate roots. The mesiobuccal root was fused with the palatal root in 3% of specimens and with the distobuccal root in 0.5% of teeth. In the second molars, 86% of the teeth had separate roots. The mesiobuccal root was fused with the palatal root in 6.3% of specimens and with the distobuccal root in 6.8% of teeth. Apical deltas were more frequent in the mesiobuccal root when compared with distobuccal and palatal roots of both the first and second molars. A type I canal configuration (>75%) was the most frequent in all the roots of both the first and second molars. Canal intercommunications and lateral canals were more frequent in the mesiobuccal root when compared with other roots. Conclusions, The mesiobuccal root tended to have more variations in the canal system followed by the distobuccal root, whereas the palatal root had the least. The findings in root and canal morphology of this Ugandan population were different from previous studies, which may partly be attributed to racial differences. [source]


    Maxillary, mandibular and chin advancement surgery for the treatment of obstructive sleep apnoea

    AUSTRALIAN DENTAL JOURNAL, Issue 3 2010
    R Jones
    Abstract The aim of this retrospective study was to determine the effectiveness of maxillary, mandibular and chin advancement (MMCA) surgery as a treatment for obstructive sleep apnoea and to determine the cephalometric parameters of this surgery. Twenty consecutive adult patients with obstructive sleep apnoea for whom other treatments (constant positive airway pressure, mandibular advancement splint and soft tissue surgery) had failed underwent MMCA surgery. Pre- and post-surgical polysomnography studies measuring the Respiratory Disturbance Index (RDI), minimum blood oxygen saturation (MinSaO2) and Epworth Sleepiness Scale (ESS) were compared. Lateral cephalometric radiographs measuring the pre- and post-surgical posterior airway space (PAS) were also analysed. Regression analysis indicated that the change in PAS at the level of B point largely accounted for the change in the RDI, although it was not significantly related with the postoperative oxygen saturation. MMCA surgery was found to be effective as a treatment for obstructive sleep apnoea, and improved all postoperative measures in this study. There was a significant relationship between B point, the PAS and a reduction in RDI. [source]


    Accuracy of Linear Measurement Provided by Cone Beam Computed Tomography to Assess Bone Quantity in the Posterior Maxilla: A Human Cadaver Study

    CLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 4 2008
    Sophie Veyre-Goulet DDS
    ABSTRACT Purpose: The aim of this study was to assess, for implant placement in the posterior maxilla, the accuracy of linear measurements provided by cone beam computed tomography (CBCT) using an image intensifier tube and television (TV) chain as an X-ray detector despite a loss of contrast resolution. The NewTom® 9000 (Quantitative Radiology, Verona, Italy) was used to explore the posterior maxilla. Materials and Methods: Fourteen measurements were taken in three dry maxillaries. On every anatomical site, three fiducial markers were placed on the bony crest to define a plane. Dry maxillaries were submitted to CBCT imaging examination. The maxillaries were then sawn according to the previously defined planes, and bone height and width were assessed using a caliper. The same measurements were taken on images. Results: Clinical analysis demonstrated no difference between real measurements and image measurements. Conclusions: Although cadaver bone density may not correspond to the density of vital bone, this in vitro study indicates that CBCT images provided by technique using image intensifier tube and TV chain as an X-ray detector are reliable to define the bone volume of the posterior maxilla for the purpose of planning the implant axis. [source]


    Reattachment of subgingivally fractured central incisor with an open apex

    DENTAL TRAUMATOLOGY, Issue 3 2007
    Ece Eden
    Abstract,,, A case report of a 6-year-old girl with a fractured maxillary left central incisor with an open apex is presented. The procedure used to repair the fracture included flap surgery with an intrasulcular incision and endodontic treatment. The patient was called for 3 months regular follow-up to check the root formation. At the end of 32 months just before the root was obturated by guttaperka, she fractured the same tooth. Flap surgery was repeated and the tooth was restored. The root canal was obturated with a root filling paste and guttaperka as the apex was closed. Examination 10 months after treatment revealed good periodontal health, aesthetics and normal function. [source]


    The association between incisor trauma and occlusal characteristics in individuals 8,50 years of age

    DENTAL TRAUMATOLOGY, Issue 2 2004
    Jay D. Shulman
    Abstract,,, To explore the association between incisal trauma and occlusal characteristics using oral examination and health interview data from the Third National Health and Nutrition Examination Survey 1988,1994 (NHANES III). Incisal trauma examinations were performed on 15 364 individuals 6,50 years of age using an ordinal scale developed by the National Institute of Dental and Craniofacial Research. Occlusal examinations were performed on 13 057 individuals 8,50 years of age. We fitted separate multivariate logistic regression models for maxillary and mandibular incisor trauma adjusting for socio-demographic variables (age, gender, race-ethnicity) and occlusal characteristics (overbite, overjet, open bite). 23.45% of all individuals evidenced trauma on at least one incisor, with trauma more than four times more prevalent on maxillary (22.59%) than on mandibular incisors (4.78%). Males (OR = 1.67) had greater odds of trauma than females; Whites (OR = 1.37) and non-Hispanic Blacks (OR = 1.37) had greater odds of trauma than Mexican,Americans. The odds of trauma increased with age, peaked from age 21 to 30 (OR = 2.92), and declined. As overjet increased, so did the odds of trauma. Compared to individuals with ,0-mm overjet, odds of trauma increased from 1,3 mm (OR = 1.42) to 4,6 mm (OR = 2.42) to 7,8 mm (OR = 3.24) to >8 mm (OR = 12.47). Trauma to incisors is prevalent but mostly limited to enamel. Trauma to maxillary incisors is associated with overjet, gender, race-ethnicity, and age, while trauma to mandibular incisors is associated with gender, age, and overbite. [source]


    Consequences for enamel development and mineralization resulting from loss of function of ameloblastin or enamelin

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 5 2009
    Charles E. Smith
    Although the nonamelogenin proteins, ameloblastin and enamelin, are both low-abundance and rapidly degrading components of forming enamel, they seem to serve essential developmental functions, as suggested by findings that an enamel layer fails to appear on teeth of mice genetically engineered to produce either a truncated form of ameloblastin (exons 5 and 6 deleted) or no enamelin at all (null). The purpose of this study was to characterize, by direct micro weighing, changes in enamel mineralization occurring on maxillary and mandibular incisors of mice bred for these alterations in nonamelogenin function (Ambn+/+, +/,5,6, ,5,6/,5,6, Enam+/+, +/, ,,/,). The results indicated similar changes to enamel-mineralization patterns within the altered genotypes, including significant decreases by as much as 50% in the mineral content of maturing enamel from heterozygous mice and the formation of a thin, crusty, and disorganized mineralized layer, rather than true enamel, on the labial (occlusal) surfaces of incisors and molars along with ectopic calcifications within enamel organ cells in Ambn,5,6/,5,6 and Enam,/, homozygous mice. These findings confirm that both ameloblastin and enamelin are required by ameloblasts to create an enamel layer by appositional growth as well as to assist in achieving its unique high level of mineralization. [source]


    Development of heterodont dentition in house shrew (Suncus murinus)

    EUROPEAN JOURNAL OF ORAL SCIENCES, Issue 6 2007
    Atsushi Yamanaka
    Mammalian heterodont dentition comprises incisors, canines, premolars, and molars. Although there has been intensive research, the patterning of these specific tooth types has not yet been elucidated. In order for the gene expression data to be linked with tooth type determination, it is first necessary to determine precisely the incisor-, canine-, premolar-, and molar-forming regions in the jaw primordia. To accomplish this, we studied dentition development in the house shrew (Suncus murinus), which has retained all the tooth types, using three-dimensional reconstructions from serial histological sections and the Sonic hedgehog (Shh) expression patterns. Before the appearance of morphological signs of odontogenesis, Shh expression localized to the presumptive tooth-forming regions, in which the mesial and distal expression domains corresponded to the incisor- and premolar-forming regions, respectively. The upper incisor region was found to extend across the boundary between the frontonasal and the maxillary processes. The canine-forming regions later appeared in the intermediate portions of the maxillary and the mandibular processes. The molar-forming regions later appeared distal to the initially demarcated tooth-forming regions by secondary extension of the distal ends. The demarcation visualized by the Shh expression pattern in the jaw primordia of the house shrew probably represents the basic developmental pattern of mammalian heterodont dentition. [source]


    Antiepileptic Drugs in the Management of Cluster Headache and Trigeminal Neuralgia

    HEADACHE, Issue 2001
    Todd D. Rozen MD
    Cluster headache and trigeminal neuralgia are relatively rare but debilitating neurologic conditions. Although they are clinically and diagnostically distinct from migraine, many of the same pharmacologic agents are used in their management. For many patients, the attacks are so frequent and severe that abortive therapy is often ineffective; therefore, chronic preventive therapy is necessary for adequate pain control. Cluster headache and trigeminal neuralgia have several distinguishing clinical features. Cluster headache is predominantly a male disorder; trigeminal neuralgia is more prevalent in women. Individuals with cluster headaches often develop their first attack before age 25; most patients with trigeminal neuralgia are between age 50 and 70. Cluster headaches are strongly associated with tobacco smoking and triggered by alcohol consumption; trigeminal neuralgia can be triggered by such stimuli as shaving and toothbrushing. Although the pain in both disorders is excruciating, cluster headache pain is episodic and unilateral, typically surrounds the eye, and lasts 15 to 180 minutes; the pain of trigeminal neuralgia lasts just seconds and is usually limited to the tissues overlying the maxillary and mandibular divisions of the trigeminal nerve. Cluster headache is unique because of its associated autonomic symptoms. Although the pathophysiology of cluster headache and trigeminal neuralgia are not completely understood, both appear to have central primary processes, and these findings have prompted investigations of the effectiveness of the newer antiepileptic drugs for cluster headache prevention and for the treatment of trigeminal neuralgia. The traditional antiepileptic drugs phenytoin and carbamazepine have been used for the treatment of trigeminal neuralgia for a number of years, and while they are effective, they can sometimes cause central nervous system effects such as drowsiness, ataxia, somnolence, and diplopia. Reports of studies in small numbers of patients or individual case studies indicate that the newer antiepileptic drugs are effective in providing pain relief for trigeminal neuralgia and cluster headache sufferers, with fewer central nervous system side effects. Divalproex has been shown to provide effective pain control and to reduce cluster headache frequency by more than half in episodic and chronic cluster headache sufferers. Topiramate demonstrated efficacy in a study of 15 patients, with a mean time to induction of cluster headache remission of 1.4 weeks (range, 1 day to 3 weeks). In the treatment of trigeminal neuralgia, gabapentin has been shown to be effective in an open-label study. When added to an existing but ineffective regimen of carbamazepine or phenytoin, lamotrigine provided improved pain relief; it also may work as monotherapy. Topiramate provided a sustained analgesic effect when administered to patients with trigeminal neuralgia. The newer antiepileptic drugs show considerable promise in the management of cluster headache and trigeminal neuralgia. [source]


    Apical transportation created using three different patency instruments

    INTERNATIONAL ENDODONTIC JOURNAL, Issue 7 2010
    J. A. Gonzalez Sanchez
    Gonzalez Sanchez JA, Duran-Sindreu F, Albuquerque Matos M, Garcia Carabaño T, Mercade Bellido M, Morello Castro S, Roig Cayón M. Apical transportation created using three different patency instruments. International Endodontic Journal 43, 560,564, 2010. Abstract Aim, To evaluate root canal transportation at the major foramen through the use of stainless steel size 08 K-Flex files, size 10 reamers, and XF finger spreaders when used as patency instruments. Methodology, One hundred and two mesiobuccal canals of maxillary and mandibular first molars were randomly divided into three groups (34 canals each). Size 08 stainless steel K-Flex files, size 10 stainless steel reamers and stainless steel XF finger spreaders were used as patency instruments in groups A, B and C respectively. The major foramen was photographed before and after instrumentation. The images were superimposed and then evaluated using Photoshop® to determine the frequency of apical transportation. The statistic analysis was performed using ,2test. Results, Transportation was detected in 22% of the specimens; 9% in group A, 12% in group B and 44% in group C. Significant differences were observed between groups A and C (P = 0.0025) and between groups B and C (P = 0.0069), but not between groups A and B (P = 1.00). Conclusions, No transportation was found in the majority of the samples when size 08 K-Flex files and size 10 stainless steel reamers were used. The XF finger spreaders, when used to maintain apical patency, caused the greatest transportation of the major foramen. [source]


    Toothache referred from auriculotemporal neuralgia: case report

    INTERNATIONAL ENDODONTIC JOURNAL, Issue 9 2009
    R. A. Murayama
    Abstract Aim, To present a 52-year-old male patient who complained of intense pain of short duration in the region of the left external ear and in the ipsilateral maxillary second molar that was relieved by blockade of the auriculotemporal nerve in the infratemporal fossa. Summary, Extra- and intraoral physical examination revealed a trigger point that reproduced the symptoms upon finger pressure in the ipsilateral auriculotemporal nerve and in the outer auricular pavilion. The patient's medical history was unremarkable. The maxillary left second molar tooth was not responsive to pulp sensitivity testing and there was no pain upon percussion or palpation of the buccal sulcus. Periapical radiographs revealed a satisfactory root filling in the maxillary left second molar. On the basis of the clinical signs and symptoms, the auriculotemporal was blocked with 0.5 mL 2% lidocaine and 0.5 mL of a suspension containing dexamethasone acetate (8 mg mL,1) and dexamethasone disodium sulfate (2 mg mL,1), with full remission of pain 6 months later. The diagnosis was auriculotemporal neuralgia. Key learning point ,,Auriculotemporal neuralgia should be considered as a possible cause of nonodontogenic toothache and thus included in the differential diagnoses. ,,The blockade of the auriculotemporal nerve in the infratemporal fossa is diagnostic and therapeutic. It can be achieved with a solution of lidocaine and dexamethasone. [source]


    Effectiveness in cleaning oval-shaped root canals using Anatomic Endodontic Technology, ProFile and manual instrumentation: a scanning electron microscopic study

    INTERNATIONAL ENDODONTIC JOURNAL, Issue 6 2005
    O. Zmener
    Abstract Aim, To compare in vitro the cleanliness of root canal walls in oval-shaped root canals following automated or manual instrumentation. Methodology, Forty-five oval-shaped single-rooted maxillary and mandibular premolars with straight canals were divided into three groups of 15. Automated canal preparation was performed using Anatomic Endodontic Technology (AET, group 1) and the ProFile system (group 2). Manual instrumentation (group 3) was performed with K-Flexofiles. Irrigation was performed using alternately 5.25% NaOCl and 17% EDTA, followed by rinsing with saline. The roots were split longitudinally into halves and the canals examined at ×200 and ×400 in a scanning electron microscope. The presence of debris and smear layer was recorded at distances of 1, 5 and 10 mm from the working length using a three-step scoring scale and a 300 ,m square grid. Mean scores for debris and smear layer were calculated and statistically analysed for significance (P < 0.05) between and within groups, using the Kruskal,Wallis nonparametric anova and Dunn's tests. Results, At 1, 5 and 10-mm levels the root canals prepared with AET had significantly less surface debris and smear layer on the canal walls compared with canals prepared with ProFile or manual instrumentation. For all three groups significantly lower mean smear layer scores (P < 0.05) were recorded at 5 and 10-mm levels compared with the 1 mm level. Significantly lower mean debris scores (P < 0.05) were also recorded at 5 and 10-mm levels for the AET group whereas no significant differences were found between the three levels for the ProFile and manual instrumentation groups. Conclusions, Although better instrumentation scores were obtained in canals prepared with AET, complete cleanliness was not achieved by any of the techniques and instruments investigated. [source]


    Identification of root canals in molars by tuned-aperture computed tomography

    INTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2000
    R. Nance
    Abstract Aim To compare the tuned-aperture computed tomography system of imaging to conventional D-speed film for their ability to identify root canals in extracted human molars. Methodology Thirteen maxillary and six mandibular human molars were mounted in acrylic blocks to simulate clinical conditions by surrounding the teeth with a radiodense structure. The teeth were then imaged with conventional D-speed film using a standard paralleling technique, and with a modified orthopantomograph OP100 machine using a Schick no. 2 size CCD sensor as the image receptor. The source images were registered and TACT slices were generated using TACT WorkbenchÔ Software. Three observers were asked to identify the number of canals in the conventional film group and the TACT image group using specific criteria. Ground truth was established by cross-sectioning the teeth at the coronal, middle, and apical thirds of the roots and directly visualizing the root canal morphology. Results TACT imaging detected 36% of 4th canals in maxillary molars and 80% of third canals in mandibular molars. Conventional film detected 0% of fourth canals in maxillary molars and 0% of third canals in mandibular molars. The differences in canal detection between the two techniques were statistically significant (Wilcoxon matched pair sign rank test, P = 0.001). Conclusions In this study, the TACT system of digital imaging was superior to conventional film in the detection of root canals in human molars and may be useful for the detection of root canals that will probably be missed upon conventional X-ray examination. [source]


    Thalassemia: macroscopic and radiological study of a case

    INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 3 2007
    A. Lagia
    Abstract Differentiation of the genetic and the acquired anaemias, particularly in areas of the world where they may co-exist, has been a challenge for palaeopathologists for over 100 years. In this paper we present macroscopic and radiographic skeletal lesions that are associated with the thalassemias in a 14-year-old girl from a modern reference collection of the University of Athens. This individual is of known sex, age, cause of death, place and dates of birth and death. The case is examined in terms of epidemiology, growth, distribution and severity of lesions and differential diagnosis. The entire skeleton is affected by marrow hyperplasia: lesions of the axial skeleton are extreme, and the appendicular skeleton is severely affected as well. The odontofacial manifestations that are diagnostic of thalassemia and differentiate it from other anaemias are present and include: maxillary and mandibular hyperplasia, reduced sinuses, displacement of maxillary dental structures, overbite, and generalised osteopenia. The development of extreme bone lesions and the ,advanced' age-at-death of this individual is explained as either the result of thalassemia major under a low transfusion regimen that was the norm during her lifetime, or to a form of thalassemia intermedia that allows survival to later life at the expense of gross skeletal alterations. The present status of skeletal studies in Greece does not support the identification of a genetic anaemia in past populations. The potential contribution of the current analysis in differentiating the anaemias in antiquity is evaluated. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    Estimating age by tooth wear of prehistoric human remains in Brazilian archaeological sites

    INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 5 2006
    R. N. Oliveira
    Abstract The occlusal surfaces of 298 permanent maxillary and mandibular molar teeth of prehistoric shellfish-gatherer subjects from the Piaçaguera and Tenorio sites (4930 to 1875 BP), near the central-northern coastline of São Paulo, Brazil, were examined for classification of macro-wear stages. Molar tooth wear is an indication of masticatory activity and can be used in the estimation of age at death. The examination of visual and schematic aspects of occlusal macro-wear used a visual chart proposed by Brothwell, which includes the three superior and inferior, left and right, permanent molars. Three examiners performed the macroscopic observations twice under the same conditions. The resulting age estimates were compared with previous information of age estimated by skeletal examination. A reduced intra- and inter-observer variation was observed; all re-examinations indicated discrepancies of less than two years for the upper and lower limit of the age range estimates. The procedure was also considered consistent with the skeletal method used for age estimation of human remains excavated in Brazilian archaeological shell mounds, with a discrepancy of less than 8.22 years between the upper and lower limits of estimates by both methods. Age classification by the occlusal molar wear may be a useful tool for the classification of archaeological findings, mainly when only fragmentary skeletal remains are excavated. The current results indicate that the application of the Brothwell chart for Brazilian archaeological series presented satisfactory results of consistency, and its expanded use may represent a relevant adjunct for research. Copyright © 2006 John Wiley & Sons, Ltd. [source]


    Hydrodynamic sorting in a coastal marine skeletal assemblage

    INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 4 2002
    *Article first published online: 9 AUG 200, Christopher M. Stojanowski
    Abstract In this paper I evaluate the effects of wave and tidal erosion on element-specific measures of phenotypic variability. Previous research has found a high correlation between skeletal weight, shape, and density and the transport potential of an element exposed to hydrodynamic forces. However, no previous studies have attempted to address the issue of within-element sorting based on selective removal of only the smallest members of a given element class. I evaluate this hypothesis using a human skeletal sample from Bird Island (8DI52) located in Dixie County, Florida. This sample comprises two components, an eroded sample that was exposed during severe storm and tidal activity, and an uneroded sample excavated from primary context. The measurement-specific means for the subcomponents were compared using Student's t and Wilcoxon tests and variability differences were evaluated based on standard deviations, coefficients of variation, and maximum/minimum indices. The data included maxillary and mandibular tooth dimensions and postcranial metrics. No evidence for selective winnowing based on within-element size was found in this data set. Copyright © 2002 John Wiley & Sons, Ltd. [source]


    Dental arch morphological and dimensional characteristics in Jordanian children and young adults with ,-thalassaemia major

    INTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 2 2005
    A. AL-WAHADNI
    Summary. Objective. , The aim of this study was to examine the arch dimensions of Jordanian patients with ,-thalassaemia major in comparison with an unaffected control group. Methods. , The sample consisted of 24 patients who suffered from ,-thalassaemia major (mean age = 13·9 ± 3·1 years) and an unaffected control group (mean age = 13·5 ± 2·9 years) matched for dental age, sex, and incisor and molar relationships. The unaffected control group was randomly selected from four public schools in the Governate of Irbid-Jordan. Alginate impressions were taken of the maxillary and mandibular dental arches of all participants. All measurements of the arch dimensions were made on the casts using an electronic digital sliding calliper. Results. , In the mandibular arch, when compared with the patients with thalassaemia, the unaffected control group subjects showed a (statistically) significantly larger incisor width, larger arch depth, and larger left and right anterior arch lengths (1·18, 2·58, and 1·85 and 1·12 mm, respectively). In the maxillary arch, there was a statistically significant difference in the mean incisor width (± 2·16 mm), arch depth (± 3·14 mm), inter-molar width (± 1·21 mm) and in the left anterior arch length (± 1·97 mm). The canine widths, premolar widths, left and right posterior arch length, and curve of Spee of both arches showed no statistically significant differences between the two groups. Conclusion. , When compared to unaffected subjects, patients with ,-thalassaemia major exhibited: a narrower maxilla; a shorter maxilla and mandible; and smaller incisor widths for the maxillary and mandibular arches. [source]


    Hunter-Schreger Band patterns in human tooth enamel

    JOURNAL OF ANATOMY, Issue 2 2010
    Christopher D. Lynch
    Abstract Using light microscopy, we examined Hunter-Schreger Band (HSB) patterns on the axial and occlusal/incisal surfaces of 160 human teeth, sectioned in both the buccolingual and mesiodistal planes. We found regional variations in HSB packing densities (number of HSBs per mm of amelodentinal junction length) and patterns throughout the crown of each class of tooth (maxillary and mandibular: incisor, canine, premolar, and molar) examined. HSB packing densities were greatest in areas where functional and occlusal loads are greatest, such as the occlusal surfaces of posterior teeth and the incisal regions of incisors and canines. From this it is possible to infer that the behaviour of ameloblasts forming enamel prisms during amelogenesis is guided by genetic/evolutionary controls that act to increase the fracture and wear resistance of human tooth enamel. It is suggested that HSB packing densities and patterns are important in modern clinical dental treatments, such as the bonding of adhesive restorations to enamel, and in the development of conditions, such as abfraction and cracked tooth syndrome. [source]


    Tooth-related risk factors for periodontal disease in community-dwelling elderly people

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 6 2010
    Toshinobu Hirotomi
    Hirotomi T, Yoshihara A, Ogawa H, Miyazaki H. Tooth-related risk factors for periodontal disease in community-dwelling elderly people. J Clin Periodontol 2010; 37: 494,500. doi: 10.1111/j.1600-051X.2010.01565.x. Abstract Objective: While most previous epidemiological studies have focused on subject-level risk factors for periodontal destruction, tooth-related factors have not been fully explored. The purpose of this study was to evaluate both tooth-related and subject-related factors affecting periodontal disease progression using a two-level multilevel model. Material and Methods: A longitudinal survey over a period of 10 years was carried out on 286 community-dwelling elderly subjects aged 70 years at baseline. Clinical attachment level (CAL) was measured at six sites per tooth on all teeth present and periodontal disease progression was defined as CAL3 mm. Results: Periodontal disease progression was found in 79% of the subjects and most frequently in maxillary molars. Multilevel logistic regressions revealed that subjects wearing removable dentures were significantly at risk for periodontal disease progression. Abutment teeth for removable/fixed dentures were also significantly more likely to suffer periodontal breakdown. Furthermore, the following tooth-related variables were found to be possible risk factors for periodontal disease progression: maxillary and multirooted teeth. Conclusion: Multirooted teeth and abutments for a fixed denture were possible risk factors for periodontal disease progression. [source]


    Thickness of gingiva in association with age, gender and dental arch location

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 7 2005
    K. L. Vandana
    Abstract Background: It has been long known that the clinical appearance of healthy marginal periodontium differs from subject to subject and even among different tooth types. Many features are genetically determined; others seem to be influenced by tooth size, shape and position and biological phenomena such as gender, growth and age. Aim: The purpose of this study was to determine the thickness of facial gingiva among Indians and its association with age, gender and dental arch. Methods: The study group included 16 males and 16 females with an age range of 16,38 years. Gingival thickness was assessed in the maxillary and mandibular anteriors by transgingival probing. Results: It was observed that the younger age group had significantly thicker gingiva than that of the older age group. The gingiva was found to be thinner in females than males and, in the mandibular arch than the maxilla. Conclusion: In the present study, it was concluded that gingival thickness varies according to age, gender and dental arch. [source]


    Hereditary gingival fibromatosis: a case report

    JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 9 2002
    Isabel Poiares Baptista
    Abstract Background/Aims: Hereditary gingival fibromatosis is characterized by various degrees of attached gingival overgrowth. It usually develops as an isolated disorder but can be one feature of a syndrome. A case of a 38-year-old female is reported who presented a generalized severe gingival overgrowth, involving the maxillary and mandibular arches and covering almost all teeth. The clinical differential diagnosis included drug-induced overgrowth as well as idiopathic gingival fibromatosis. Treatment: Excess gingival tissue was removed by conventional gingivectomy. As the gingival enlargement was generalized to all quadrants, on both sides, the surgery was carried out under general anaesthesia. The postoperative course was uneventful and the patient's appearance improved considerably. Post-surgical follow-up after 20 months demonstrated a slight recurrence Conclusions: Hereditary gingival fibromatosis is a rare disorder characterized by the proliferative fibrous overgrowth of the gingival tissue. Resective surgery of the excess tissue is the treatment available. However, recurrence is a common feature. [source]


    TOOTH WHITENING IN CHILDREN

    JOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 6 2005
    K.J. Donly
    ABSTRACT Objective: This clinical study evaluated the efficacy and tolerability of tooth whitening in children and adolescents, using a marketed, tray- based tooth-whitening system and a disposable polyethylene strip system. Materials and Methods: A study population of 106 children and adolescents, ages 11 to 18 years, participated in this study. There were 61 girls and 45 boys, with a mean age of 14.7 years. Subjects were divided into two experimental treatment groups, the groups being balanced with respect to demographic characteristics and baseline tooth color. All subjects had to have all permanent anterior teeth erupted, a baseline Vita shade (Vita Zahnfabrik, Bad Säckingen, Germany) score of A2 or darker, and the desire to whiten their teeth. One experimental group included 71 subjects who used a 6.5% hydrogen peroxide strip system (Crest Whitestrips Professional Strength, Procter & Gamble, Mason, OH, USA) for 30 minutes twice daily. The other experimental group included 35 subjects who used a 10% carbamide peroxide tray system (Opalescence, Ultradent Products, South Jordan, UT, USA) overnight. Subjects who had previously vital bleached their teeth, exhibited apparent caries or periodontal problems, had orthodontic appliances or anterior restorations, or reported dentin hypersensitivity were excluded. The study population was treated in two separate cohorts, by two independent investigations, to minimize the effects of examiner bias. Digital images were collected for all subjects at baseline, 2 weeks, and 4 weeks, with the maxillary and mandibular arches being treated separately for 4-week intervals. An oral examination was conducted at baseline and at all recall intervals. Subjects reported any adverse events in interviews. Color change was calculated from digital images where L* indicated lightness, a* redness, and b* yellowness. Comparisons between the two experimental groups were made using a two-sided analysis of covariance with a 5% significance level. Results: Both experimental systems exhibited significant (p < .001) tooth-whitening improvement relative to the baseline. Color change was greater in the maxillary teeth than in the mandibular teeth for both systems evaluated. The color change for maxillary teeth was not significantly different between the two systems evaluated; however, the tray system demonstrated significantly (p < .05) greater toothwhitening effectiveness for the mandibular teeth. Both treatment regimens were well tolerated. Minor tooth sensitivity and oral irritation were the most commonly reported adverse events, being reported by 49% of the subjects assigned to the strip group and 43% of the subjects in the tray group. All reported that adverse events were relieved immediately upon discontinuance of product use. Conclusion: The 6.5% hydrogen peroxide gel strips and the 10% carbamide peroxide gel delivered overnight in customized trays effectively whitened teeth, and both treatment regimens were well tolerated. [source]


    Greening of the Tooth,Amalgam Interface during Extended 10% Carbamide Peroxide Bleaching of Tetracycline-Stained Teeth: A Case Report

    JOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 1 2002
    VAN B. HAYWOOD DMD
    ABSTRACT At-home bleaching with 10% carbamide peroxide in a custom-fitted tray has been shown to have some minor effects on certain brands of amalgam, pertaining to mercury release, but generally, effects on amalgam are not considered clinically significant. However, in this case report, a greening of the tooth structure in certain areas immediately adjacent to amalgam restorations in the maxillary and mandibular first molars occurred during tooth whitening. Other amalgam restorations in mandibular and maxillary second molars in the same mouth did not demonstrate any green discoloration of the teeth. Upon removal of the affected amalgam restorations, recurrent decay was present in the areas of tooth greening but not in other areas adjacent to the restoration. The teeth were restored with posterior composite restorations. Whether the green discoloration was a result of some loss of material from a particular brand of amalgam, indicating leakage, or indicative of original or recurrent tooth decay is unclear in this single-patient situation. Other patients in the same study did not demonstrate this occurrence. Dentists should be ready to replace amalgam restorations should this green discoloration in adjacent tooth structure occur during bleaching, in case decay is present. CLINICAL SIGNIFICANCE The unusual discoloration cited suggests that amalgam restorations in potentially esthetic areas, including the lingual of anterior teeth, should be replaced prior to bleaching, to avoid the problem of difficult stain removal or translucency allowing restoration visibility following bleaching. [source]


    Osteology and myology of the cephalic region and pectoral girdle of Plotosus lineatus, with comments on Plotosidae (Teleostei: Siluriformes) autapomorphies

    JOURNAL OF FISH BIOLOGY, Issue 2 2001
    C. Oliveria
    From comparisons of the cephalic and pectoral girdle structures of Plotosus lineatus with those of other plotosid as well as non-plotosid siluriforms, plotosid catfishes can be defined by at least six autapomorphies. These are: (1) the absence of the ventral division of the muscle arrector dorsalis; (2) the double articulation between the neurocranium and the anterior part of the suspensorium; (3) the greatly enlarged utricular otolith, which profoundly inflates the ventral surfaces of both the prootic and the pterotic; (4) the attachment of the muscle extensor tentaculi on the neurocranium lies further anteriorly than its insertion on the autopalatine; (5) the coronoid process of the mandible is linked to the maxillary by means of two thick, long ligaments; (6) the enlarged base of the maxillary barbel. [source]


    Age Estimation of Korean Adults by Occlusal Tooth Wear

    JOURNAL OF FORENSIC SCIENCES, Issue 3 2007
    Jong-Il Yun M.S.D.
    ABSTRACT: The aim of the present study was to evaluate the validity of the modified Kim's scoring system as a practical method of recording occlusal tooth wear and estimating age. For this purpose, 1092 pairs of maxillary and mandibular full-arch casts were randomly selected, scored, and analyzed. The results showed that the modified Kim's scoring system had excellent reliability, and that occlusal tooth wear had a positive correlation with age. Tooth wear scores of all teeth except the two lower central incisors were higher in males than in females. Calculating tables for age estimation were designed by multiple linear regression analysis. Estimated ages were within ±5 years of actual ages in 63.5% of male subjects, and 64.0% of female subjects. The accuracy of age estimation was increased when the subjects were divided into two age groups and data were re-analyzed. Collectively, it was shown that the modified Kim's scoring system is a reliable and accurate method for age estimation, and that the data from these 1092 individuals can be used as a standard for age estimation of Korean adults. [source]


    Agnathia and associated malformations in a male rhesus monkey

    JOURNAL OF MEDICAL PRIMATOLOGY, Issue 4 2008
    B. Goldschmidt
    Abstract Background, Agnathia is a rare malformation characterized by the absence of the mandible. Methods, A male rhesus monkey with malformations was found dead and studied by internal examination, radiographs and histopathology. Results, A case of a rare first branchial arch anomaly with agenesis of the mandible and tongue is presented. The animal also had visceral deformities. However, ears were normal in shape and only slightly low in position. The craniofacial malformations may reflect incomplete separation of the first branchial arch into its maxillary and mandibular processes. Conclusions, The association between the craniofacial and other corporal anomalies is unclear. [source]


    Comparative anatomy of the cheek muscles within the Centromochlinae subfamily (Ostariophysi, Siluriformes, Auchenipteridae)

    JOURNAL OF MORPHOLOGY, Issue 2 2006
    Luisa Maria Sarmento-Soares
    Abstract Glanidium melanopterum Miranda Ribeiro, a typical representative of the subfamily Centromochlinae (Siluriformes: Auchenipteridae), is herein described myologically and compared to other representative species within the group, Glanidium ribeiroi, G. leopardum, Tatia neivai, T. intermedia, T. creutzbergi, Centromochlus heckelii, and C. existimatus. The structure of seven pairs of striated cephalic muscles was compared anatomically: adductor mandibulae, levator arcus palatini, dilatator operculi, adductor arcus palatini, extensor tentaculi, retractor tentaculi, and levator operculi. We observed broad adductor mandibulae muscles in both Glanidium and Tatia, catfishes with depressed heads and smaller eyes. Similarities between muscles were observed: the presence of a large aponeurotic insertion for the levator arcus palatini muscle; an adductor arcus palatini muscle whose origin spread over the orbitosphenoid, pterosphenoid, and parasphenoid; and the extensor tentaculi muscle broadly attached to the autopalatine. There is no retractor tentaculi muscle in either the Glanidium or Tatia species. On the other hand, in Centromochlus, with forms having large eyes and the tallest head, the adductor mandibulae muscles are slim; there is a thin aponeurotic or muscular insertion for the levator arcus palatini muscle; the adductor arcus palatini muscle originates from a single osseous process, forming a keel on the parasphenoid; the extensor tentaculi muscle is loosely attached to the autopalatine, permitting exclusive rotating and sliding movements between this bone and the maxillary. The retractor tentaculi muscle is connected to the maxilla through a single tendon, so that both extensor and retractor tentaculi muscles contribute to a wide array of movements of the maxillary barbels. A discussion on the differences in autopalatine-maxillary movements among the analyzed groups is given. J. Morphol. © 2005 Wiley-Liss, Inc. [source]


    Biomechanics of the rostrum and the role of facial sutures

    JOURNAL OF MORPHOLOGY, Issue 1 2003
    Katherine L. Rafferty
    Abstract The rostrum is a large diameter, thin-walled tubular structure that receives loads from the teeth. The rostrum can be conceptualized both as a rigid structure and as an assemblage of several bones that interface at sutures. Using miniature pigs, we measured in vivo strains in rostral bones and sutures to gain a better understanding of how the rostrum behaves biomechanically. Strains in the premaxillary and nasal bones were low but the adjacent maxillary-premaxillary, internasal, and intermaxillary suture strains were larger by an order of magnitude. While this finding emphasizes the composite nature of the rostrum, we also found evidence in the maxillary and nasal bones for rigid structural behavior. Namely, maxillary strain is consistent with a short beam model under shear deformation from molar loading. Strain in the nasal bones is only partially supported by a long beam model; rather, a complex pattern of dorsal bending of the rostrum from incisor contact and lateral compression is suggested. Torsion of the maxilla is ruled out due to the bilateral occlusion of pigs and the similar working and balancing side strains, although it may be important in mammals with a unilateral bite. Torsional loading does appear important in the premaxillae, which demonstrate working and balancing side changes in strain orientation. These differences are attributed to asymmetrical incisor contact occurring at the end of the power stroke. J. Morphol. 257:33,44, 2003. © 2003 Wiley-Liss, Inc. [source]


    Dentition and tooth replacement pattern in Chalcides (Squamata; Scincidae)

    JOURNAL OF MORPHOLOGY, Issue 2 2003
    Sidney Delgado
    Abstract This study was undertaken as a prerequisite to investigations on tooth differentiation in a squamate, the Canarian scincid Chalcides. Our main goal was to determine whether the pattern of tooth replacement, known to be regular in lizards, could be helpful to predict accurately any stage of tooth development. A growth series of 20 laboratory-reared specimens, aged from 0.5 month after birth to about 6 years, was used. The dentition (functional and replacement teeth) was studied from radiographs of jaw quadrants. The number of tooth positions, the tooth number in relation to age and to seasons, and the size of the replacement teeth were recorded. In Chalcides, a single row of pleurodont functional teeth lies at the labial margin of the dentary, premaxillary, and maxillary. Whatever the age of the specimens, 16 tooth positions were recorded, on average, in each quadrant, suggesting that positions are maintained throughout life. Replacement teeth were numerous whatever the age and season, while the number of functional teeth was subject to variation. Symmetry of tooth development was evaluated by comparing teeth two by two from the opposite side in the four jaw quadrants of several specimens. Although the relative size of some replacement teeth fitted perfectly, the symmetry criterion was not reliable to predict the developmental stage of the opposite tooth, whether the pair of teeth compared was left,right or upper,lower. The best fit was found when comparing the size of successive replacement teeth from the front to the back of the jaw. Every replacement tooth that is 40,80% of its definitive size is followed, in the next position on the arcade, by a tooth that is, on average, 20% less developed. Considering teeth in alternate positions (even and odd series), each replacement tooth was a little more developed than the previous, more anterior, one (0.5,20% when the teeth are from 10,40% of their final size). The latter pattern showed that tooth replacement occurred in alternate positions from back to front, forming more or less regular rows (i.e., "Zahnreihen"). In Chalcides, the developmental stage of a replacement tooth in a position p can be accurately predicted provided the developmental stage of the replacement tooth in position p-1 or, to a lesser degree, in position p-2 is known. This finding will be particularly helpful when starting our structural and ultrastructural studies of tooth differentiation in this lizard. J. Morphol. 256:146,159, 2003. © 2003 Wiley-Liss, Inc. [source]


    Conservation of the function counts: homologous neurons express sequence-related neuropeptides that originate from different genes

    JOURNAL OF NEUROCHEMISTRY, Issue 3 2009
    Susanne Neupert
    Abstract By means of single-cell matrix assisted laser desorption/ionization time-of-flight mass spectrometry, we analysed neuropeptide expression in all FXPRLamide/pheromone biosynthesis activating neuropeptide synthesizing neurons of the adult tobacco hawk moth, Manduca sexta. Mass spectra clearly suggest a completely identical processing of the pheromone biosynthesis activating neuropeptide-precursor in the mandibular, maxillary and labial neuromeres of the subesophageal ganglion. Only in the pban -neurons of the labial neuromere, products of two neuropeptide genes, namely the pban -gene and the capa -gene, were detected. Both of these genes expressed, amongst others, sequence-related neuropeptides (extended WFGPRLamides). We speculate that the expression of the two neuropeptide genes is a plesiomorph character typical of moths. A detailed examination of the neuroanatomy and the peptidome of the (two) pban -neurons in the labial neuromere of moths with homologous neurons of different insects indicates a strong conservation of the function of this neuroendocrine system. In other insects, however, the labial neurons either express products of the fxprl -gene or products of the capa -gene. The processing of the respective genes is reduced to extended WFGPRLamides in each case and yields a unique peptidome in the labial cells. Thus, sequence-related messenger molecules are always produced in these cells and it seems that the respective neurons recruited different neuropeptide genes for this motif. [source]


    Electromyographic activity of masticatory, neck and trunk muscles of subjects with different skeletal facial morphology , a cross-sectional evaluation

    JOURNAL OF ORAL REHABILITATION, Issue 7 2007
    S. TECCO
    summary, The electromyographic pattern activity of masticatory, neck and trunk muscles was assessed using surface electromyography (sEMG) in 60 Caucasian adult females (20 subjects in skeletal class I, 20 subjects in skeletal class II and 20 subjects in skeletal class III), classified on the base of their skeletal class (ANB angle), corrected on the base of maxillary and mandibular rotations. The sEMG activity was recorded at mandibular rest position and during maximal voluntary clenching. At mandibular rest position, the sEMG activities of masseter and anterior temporal muscles were significantly higher in class III subjects than in class I and class II subjects, that showed no significant difference between them. Then, the sEMG activities of posterior cervicals and upper trapezius were significantly higher in skeletal class III subjects than in the other two groups. During maximal voluntary clenching, no significant difference was observed in the sEMG activity of masticatory muscles among the three considered groups. However, the sEMG activities of posterior cervicals and upper trapezius were significantly higher in skeletal class III subjects than in the other two groups, which showed no significant difference between them. In conclusion, the skeletal class seems to affect the sEMG pattern activity of masticatory, neck and trunk muscles. [source]