Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Maxilla”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed2004

Early function of splinted implants in maxillas and posterior mandibles, using Brånemark System Tiunite implants: an 18-month prospective clinical multicenter study.

BACKGROUND: Immediate or early loading of implants placed in maxillas and posterior mandibles has been a concern as bone density is often low in these areas, making it difficult to establish good initial implant stability. By adapting implant design and insertion protocols, however, high initial implant stability may be achieved in these regions. Further, a modified implant surface texture has been proved to help in maintaining stability during the initial healing period. PURPOSE: The aim of the present study was to investigate the clinical performance of oxidized titanium implants (TiUnite, Nobel Biocare AB, Gothenburg, Sweden) when used for early function in the maxilla and in the posterior mandible, locations where the bone density often is low. A further aim was to evaluate the marginal bone level at oxidized implants and compare it with that of machined-surface implants used in a previous study. MATERIALS AND METHODS: Thirty-one patients were consecutively included in the study, and 37 edentulous areas in maxillas and posterior mandibles were treated. Bruxism and uncontrolled periodontal disease were exclusion criteria. Temporary prostheses were generally placed within 9 days but not after 16 days from implant placement. A previous study applying the same study design and clinical protocol but using machined-surface implants was used for comparisons. RESULTS: Of the 111 implants installed, 1 failed, giving an overall survival rate of 99.1% after 18 months. The prosthesis survival was 100%. The marginal bone resorption was 0.8 mm (standard deviation [SD], 1.0), as opposed to 1.6 mm (SD, 1.3) in the previous study with machined-surface implants, but was not statistically significantly different (p = .10). CONCLUSION: The present clinical protocol (aiming at high primary stability) and the use of oxidized titanium implants for early functional loading in the maxilla and the posterior mandible resulted in a high implant survival rate and a favorable marginal bone level during a follow-up of 18 months. The difference in marginal bone resorption between the oxidized implants in the present study and the machined implants from a previous investigation with the same study design was not statistically significant.

Adult↗
PubMedDate not supplied

Ameloblastoma of the maxilla and peripheral ameloblastomas.

Ameloblastomas arising in the supraperiosteal soft tissues (peripheral ameloblastoma) and those taking origin in the maxilla have distinctively different biologic behaviors. The peripheral ameloblastoma can be successfully treated by conservative excision while en bloc resection is warranted for the maxillary ameloblastoma. The effectiveness of primary surgical treatment of an ameloblastoma of the maxilla is the key to reduce morbidity and mortality from the lesion. Anatomic differences between the maxilla and mandible and an apparent more aggressive behavior of maxillary tumors also play a role in establishing the ameloblastoma of the maxilla as the most dangerous of the ameloblastomas.

Ameloblastoma↗
PubMed1999

Immediate function of cortically anchored disk-design implants without bone augmentation in moderately to severely resorbed completely edentulous maxillae.

The completely edentulous maxilla remains a challenge in implant dentistry. Conventional two-stage surgical techniques require two independent invasive surgeries separated by a 5-6-month healing period. In addition, an increased risk of trauma to the implant-bone interface may be caused by a removable transitional complete denture during the interim submerged period, which can compromise implant success or increase crestal bone loss around the implants during initial bone healing. The purpose of this clinical trial was to evaluate the safety and efficacy of immediately loading a fixed implant-supported prosthesis without bone augmentation in moderately to severely resorbed, completely edentulous maxillae. Over a 41-month period, 783 titanium implants (627 laterally inserted disk implants, with or without 156 axially inserted Structure implants) were placed in 72 consecutive patients with completely edentulous maxillae using an immediate loading protocol. After 6 months of function, the fixed restorations were removed and each implant status was verified using radiographs, Periotest evaluations, clinical osseointegration criteria, and torque testing at 20 N-cm. Six months postoperatively, 98% of the implants were radiologically and clinically osseointegrated. Fifty-six gold screws (7%) required retightening after 10 months, but no screw fractures occurred during this study period. The postrestorative follow-up of these patients ranged from 6 to 48 months. As of this report, all of the fixed prostheses remain functional, and no additional implants have been lost. This clinical trial demonstrates that immediate loading of nonsubmerged, laterally inserted disk-design implants may provide adequate primary anchorage and longterm osseointegration in completely edentulous maxillae. The initial multicortical anchorage afforded by the disk-design implant in this study, coupled with biomechanical splinting of the disks (sometimes with more traditional root-form design implants) using a rigid prosthesis, permits a one-stage predictable implant procedure offering rapid restoration of patients to masticatory function.

Adult↗
PubMed2003

Role of maxilla 2 and its setae during feeding in the shrimp Palaemon adspersus (Crustacea: Decapoda).

The movements of the basis of maxilla 2 in Palaemon adspersus were examined using macro-video recordings, and the morphology of its setae was examined using both scanning and transmission electron microscopy. The basis of maxilla 2 performs stereotypical movements in the latero-medial plane and gently touches the food with a frequency of 3-5 Hz. The medial rim of the basis of maxilla 2 carries three types of seta. Type 1 is serrate, type 2 and 3 are serrulate, and type 2 has a prominent terminal pore. Type 2 is innervated by 18-25 sensory cells whose cilia protrude through the terminal pore and are in direct contact with the external environment. The structure of type 2 setae indicates that they are mainly gustatory, although still bimodal due to their innervation by presumed chemosensory and mechanosensory neurons. Distally, the three types of setae have a complex arrangement of the cuticle involving water-filled canals, which may serve to improve flexibility. Type 1 and 3 setae have fewer sensory cells (4-9) but probably also have a bimodal sensory function. The function of type 1 setae is probably to protect type 2 setae, while type 3 setae might serve to groom the ventral side of the basis of maxilla 1.

Animal Structures↗
PubMed1999

[3-D model analysis of the maxilla of infants with lip-jaw-palate clefts].

For the investigation of three-dimensional morphological changes in the maxilla of children with cleft lip and palate, the use of two-dimensional test analysis is inadequate. Since no standardised three-dimensional method has so far been available, a three-dimensional digital, computer-aided procedure was developed to visualize and metrically analyse the growth of the edentulous maxilla of infants with cleft lip and palate. Chronologically consecutive casts of the maxillas (obtained at the ages of one week, and three, six and twelve months) of five children with complete unilateral CLP were measured optically with the instrument Micromeasure 70. Following digitation, the casts were reconstructed in the computer, aligned and superimposed using the Orthosurf program. The distances between the surfaces were then measured; in addition, the surfaces were segmented perpendicular to the alveolar crest at reference points C1, C1', C2, C2' and I. The volumes of the resulting segments were determined and compare with one another. Specially designed software automated the following steps: 1. identification of reference points; 2. alignment of the cloud of points in a system of coordinates, and 3. identification of the alveolar crest. Our initial results show that (1) the new method enables visualization of the extent and direction of morphological changes of the mucosal surface, and (2) reproducible quantification of these changes via the determination of changes in the volume of defined alveolar segments. The three-dimensional analysis presented here permits a comprehensive three-dimensional measurement of the models of the edentulous maxilla of infants with cleft lip and palate.

Cephalometry↗
PubMed1990

[Atrophy of the mandible and maxilla as complication of treatment and healing of jaw fractures].

The authors discuss in the light of literature data the causes of bone atrophy and report two own cases of extensive atrophy of the mandible and atrophy of the maxilla developed during treatment of their fractures. Parallel mandibular atrophy in a patient aged 67 years was observed 3 years after surgical union of fractured fragments of the edentulous mandible with metal plates. The cause of atrophy is related by the authors to prolonged malnutrition of the patient who had partial gaestrectomy 24 years earlier, and his failure to observe the suggested mandible immobilization during the required length of time. Considerable degree of maxilla atrophy in a 34-year-old man developed during treatment of a Le Fort III maxilla fracture. The atrophy affected mainly the apical base of the alveolar process, and it was observed 4 months after fracture. The cause was not systematic, prolonged without informing the stomatologist, and excessive traction was exerted by the rubber band in the chin-sling used for the treatment of the fracture. The treatment used in this case permitted to restore in the maxilla the proportions of bone structures approaching the normal ones.

Adult↗
PubMed2001

[Psammous desmo-osteoblastoma of the right maxilla. Case report and differential diagnosis of a rare tumor].

CASE REPORT: We report the case of a 9-year-old female patient with a moderate swelling of the right maxilla. A tumor was diagnosed by conventional X-ray within the region of tooth 17 in the right tuber maxillae. The histological diagnosis after biopsy of the lesion was "fibrous dysplasia Jaffe-Lichtenstein". One year later, the tumor was still growing, and computed tomography was carried out. The first histological diagnosis was confirmed by another biopsy; the differential diagnosis was "ossifying fibroma". In the following years, the tumor grew and expanded into the right orbit and maxilla. Four years after the first diagnosis the tumor was removed operatively. DIFFERENTIAL DIAGNOSIS OF THE OPERATIVE SPECIMEN: The histology showed round, partially trabecular or calcified bodies, known as psammoma-like ossicles. Therefore, in light of the clinical course and the radiographic appearance, the correct diagnosis was "psammous desmo-osteoblastoma". DISCUSSION: The psammous desmo-osteoblastoma and its differential diagnosis are discussed in this article.

Child↗
PubMed1999

[Significance of the height and width of the alveolar ridge in implantology in the edentulous maxilla. Analysis of 95 cadaver jaws and 24 consecutive patients].

Consideration of alveolar profiles and clinical experience demonstrate that the transversal dimension has been neglected in dental implantology so far. For a comprehensive evaluation of the impact of alveolar bone height and width, 95 edentulous bony maxillae with standardized, measured, and classified cross-sections were analyzed. With four types of implants (minimum length, 10 mm), 1076 insertions were simulated at 269 cross-sections and evaluated with regard to type of implant, position of cross-section, and class of atrophy. Similar evaluation was carried out in the clinical part of the study on 24 consecutive patients with edentulous maxillae. Implant insertion could only be simulated in 35% of the cadaver cross-sections, but had been expected in an additional 4.5% based on their sufficient bone height; length reductions were necessary in another 6%. These results depended largely on the class of atrophy. Anterior cross-sections offered better conditions than posterior ones. In contrast, implant insertion was impossible in all 24 patients. Height was primarily inadequate in 22 patients, and in two patients with sufficient bone height inadequate transversal dimensions were only recognised intraoperatively. These results allow a quantification of the impact of vertical and transversal maxillary alveolar bone dimensions. This impact primarily depends on bone height, but even with sufficient height, reductions of implant length often become necessary. Both for the cadaver maxillae (12% of the cross-sections with expected implant insertion) and for the patients (8%), alveolar profiles remain in which height measurement alone leads to incorrect assessment and may even result in the interruption of precisely planned surgical procedures. The complexity and expense of implant-borne rehabilitation and the consequences resulting from incorrect preoperative planning therefore generally justify extended cross-sectional diagnostic measuring.

Alveolar Process↗
PubMed1981

Surgical inferior repositioning of the maxilla: treatment considerations and comprehensive management.

Surgical inferior repositioning of the hypoplastic or vertically deficient maxilla is discussed with respect to various relevant treatment considerations, and a specific regimen for comprehensive management is recommended. Treatment considerations for persons with true vertical maxillary deficiency include esthetic, functional, and neuromuscular factors. Primary among these factors are the relationship between the maxillary incisor and the upper lip, the physiologic interocclusal space, and the masticatory bite force. A regimen for the comprehensive management of these factors is recommended to ensure skeletal stability. These measures include a careful surgical technique, transplantation of viable autogenous bone, critical evaluation of the physiologic interocclusal space, and elimination of destructive masticatory forces to the maxilla during healing of the graft by an intraoral skeletal fixation appliance. Adherence to these fundamental biologic principles ensures predictability to the inferiorly repositioned maxilla.

Adult↗
PubMed1982

Indications for simultaneous mobilization of the maxilla and mandible for the correction of dentofacial deformities.

As improvements in diagnosis, treatment planning, and surgical techniques have evolved it has become increasingly more common to consider simultaneous mobilization of the maxilla and mandible in order to achieve optimal correction of selected dentofacial deformities. In the experiences of the authors, there are patients with specific deformities of the Class III, Class II, Class I, and asymmetry types who can benefit from simultaneous mobilization of both jaws. It is the purpose of this article, the first in a series of three, to detail those specific conditions which warrant consideration for simultaneous mobilization of the maxilla and mandible. In the second article the details of treatment planning for simultaneous mobilization of the maxilla and the mandible will be presented, and in the third article the results of treatment in 100 consecutive cases will be evaluated.

Cephalometry↗
PubMed1991

A technique for evaluating bony changes in the anterior edentulous maxilla: a modification of a cephalometric analysis.

A modification of a cephalometric analysis is presented for evaluating maxillary bone loss in the edentulous maxilla. The analysis involves tracing a lateral cephalometric radiograph of an edentulous maxilla, identifying the new landmarks, and measuring the appropriate vertical and horizontal distances of the maxilla. Comparison of the measurements for the patient's initial or baseline radiographic analysis with those of the patient's follow-up radiographic analysis identifies the amount of bone loss that has occurred between the two examinations.

Alveolar Bone Loss↗
PubMed1989

Skeletal changes in vertical and anterior displacement of the maxilla with bonded rapid palatal expansion appliances.

The purpose of this study was to determine whether anterior and inferior displacement of the maxilla seen with rapid palatal expansion when done with a banded rapid palatal expansion appliance is significantly different from an occlusally bonded rapid palatal expansion appliance. It was hypothesized that the bonded appliance would limit unwanted displacement of the maxilla by producing vertical forces on both arches in a manner similar to a functional appliance. The study was conducted using the bonded appliance on 20 adolescents and comparing the results with those of a banded appliance population--namely, 60 cases from Wertz's study. Lateral cephalometric radiographs were taken before treatment and again after the expansion appliances were removed. The results of this study suggest that the downward and anterior displacement of the maxilla often associated with the banded rapid palatal expansion appliance may be negated or minimized with the more versatile bonded appliance.

Adolescent↗
PubMed2005

Onlay augmentation versus sinuslift procedure in the treatment of the severely resorbed maxilla: a 5-year comparative longitudinal study.

Augmentation procedures in the severely resorbed maxilla are standard techniques in preprosthetic surgery. Aim of the present study was to compare onlay bone grafting and sinus floor elevation with autogenous bone grafts in edentulous patients in terms of bone resorption of the posterior alveolar crest and implant survival in a 5-year longitudinal study. A total of 100 patients (53 female and 47 male patients) requiring augmentation using autogenous bone due to a severely resorbed maxillae were evaluated. The degree of resorption and bone quality were preoperatively estimated in panoramic radiographs according to Lekholm and Zarb. The overall 5-year success rate of implants placed after augmentation procedures in the posterior maxilla was 93.1%. Following onlay augmentations 215 out of 235 implant insertions were successful, i.e. a success rate of 91.5% was achieved. In the sinuslift group, 330 out 349 implants remained successful, i.e. a success rate of 94.6% was found. The difference between both groups was statistically significant at the end of the evaluation period. Bone resorption, measured as loss of total bone height in panoramic radiographs, was initially more pronounced following onlay augmentations (>20% after 12 months of observation). The degree of resorption decreased in the further course of the study. Lower resorption rates and a higher overall success rate were demonstrated for the sinus lift group.

Adult↗
PubMed2006

Implant reconstruction of the bone-grafted maxilla: review of the literature and presentation of 8 cases.

PURPOSE: This study prospectively investigates the long-term success of iliac crest bone grafting and the secondary placement of osseointegrated implants in reconstructing maxillae with severely reduced bone mass. MATERIALS AND METHODS: Eight consecutive patients (7 women, 1 man), aged 18 to 69 (mean, 49.6), were treated by augmentation of their maxillae with corticocancellous autogenous iliac bone blocks. Forty-one Branemark implants of 7 to 15 mm in length and 3.75 mm in diameter were placed after a minimum delay of 6 months. Bone healing, maintenance of bone height, and implant stability were measured by clinical examination and radiographic control. RESULTS: One patient was lost to follow-up at 24 months after delivery of the prosthesis and one was lost at 75 months. The average duration of follow-up after loading of the implants was 90.5 months, and the longest was 154 months. Thirty-four of 41 (83%) of the implants survived to the end of the observation period. Four of 6 implants that failed were 7 mm in length and the other 2 were 10 mm in length. One 10-mm implant was "slept" because of poor positioning. All prostheses survived. There was one significant gingival infection that resulted in loss of 1.5 mm of bone after which the implant remained stable. None of the other implants were associated with crestal bone loss of more than 0.5 mm for the duration of this study. CONCLUSIONS: Delayed placement of osseointegrated implants in maxillae augmented by iliac bone grafts is predictable and successful in the long term.

Adolescent↗
PubMed2004

Immediate reconstruction of maxilla with bone grafts supported by pedicled buccal fat pad graft.

PURPOSE: To reconstruct immediately the maxilla with bone grafts after partial maxillary resection and solve complications of exposed bone grafts to the maxillary sinus leading to a high rate of bone infection and sequestration. STUDY DESIGN: Thirty-eight patients were treated by immediate reconstruction of the maxilla with bone grafts supported by pedicled buccal fat pad (BFP) graft. The facial contour, the bone healing of the bone grafts, and the function of the maxillary sinus were evaluated with the Waters radiograph and speech evaluation. RESULTS: The postoperative healing was satisfactory with normal mouth opening and symmetrical contour of the face. The function of the maxillary sinus was restored with satisfactory speech and symmetrical density on radiograph and the healing of the bone grafts was good without complications such as bone resorption and sequestration. CONCLUSIONS: Immediate reconstruction of the maxilla with bone grafts supported by pedicled BFP grafts can restore the facial contour and the function of the maxillary sinus for the patients with partial maxillary resection. It provides a good method to reconstruct the maxillary defects and function in the mouth.

Adipose Tissue↗
PubMed2004

[Combined nasal approach: maxilla-premaxilla approach and external approach].

INTRODUCTION: A major aim of septo-rhinoplasty is the treatment of the internal and external nasal defects overall. We describe our technique with a combined external approach and maxilla-premaxilla approach in one surgical process. We present our functional and aesthetic results. METHODS: We analyse 16 patients that underwent septo-rhinoplasty using a combined approach; external approach and maxilla-premaxilla approach between 1999 and 2003. Anterior active rhinomanometry (RAA) and Anderson's scale to grade nose defects were performed before the operation and once again a year later. Furthermore, patients answered a visual analogical scale in order to know if they had noticed an improvement in nasal a year after the operation. RESULTS: RAA showed significant improvement in nose flow by 100 Pa pressure with a total flow mean of 730 cm3/s after surgery. After the operation, the majority of patients felt a definitive improvement in their nasal respiration. Scores on Anderson's scale of nose defects showed a significant improvement in nasal defects after surgery p<0.001. We achieved also a significant improvement for each pyramidal subunit. There were no complications in the healing of incisions neither patients complained of them. CONCLUSION: Nasal combined approach; external approach and maxilla-premaxilla approach in septo-rhinoplasty is a safe technique and allows functional and aesthetic improvement in nose defects, mainly in nasal base defects combined with septal defects.

Adolescent↗
PubMed2000

Soft tissue profile changes after autogenous iliac crest onlay grafting for the extremely atrophic maxilla.

PURPOSE: The aim of this study was to evaluate profile changes in the hard and soft tissues after onlay grafting in the extremely atrophic maxilla. PATIENTS AND METHODS: Onlay grafting using autogenous iliac crest bone grafts was performed in 49 patients (42 females and 7 males) with extreme atrophy of the edentulous maxilla (vertical amount of bone: <6 mm, transverse amount of bone: <5 mm). For the assessment of the changes to the hard and soft tissues, the preoperative and postoperative cephalograms were traced and the cephalometric measuring points (44 skeletal and 25 soft tissue points) were digitalized with the aid of the Dentofacial Planner System. Evaluation of a relationship between soft tissue and hard tissue profile changes was performed by comparing the movement of the skeletal points Sub-ANS and A-point with the shift of the soft tissue point SLS. To determine significant hard tissue and soft tissue changes, the measured values were evaluated using the SPSS program system and examined for statistical significance by use of the Wilcoxon test. RESULTS: An advancement of the bony maxilla profile in the sagittal direction by an average of 2.4 mm (P < .01) was found. The soft tissue profile of the upper lip was moved forward on average by 2.3 mm (P = .0039) at the superior labial sulcus point and by 2.7 mm (P = .0018) at the labrale superius point. The ratio of the soft tissue change to hard tissue change was 0.7:1 (superior labial sulcus: skeletal point sub-ANS) or 0.9:1 (superior labial sulcus: A point). CONCLUSIONS: When planning onlay graft operations, consideration should be given to the functional and aesthetic effects of the profile changes on the upper lip.

Adult↗
PubMed1996

Stability of maxilla downgrafting after rigid or wire fixation.

PURPOSE: This article compares the long-term outcomes of rigid internal fixation with wire fixation. PATIENTS AND METHODS: In this retrospective study, nine cases of vertical midface augmentation in which rigid fixation was used were compared with 11 cases with wire fixation. One surgeon completed all cases for the rigid fixation group, and another surgeon completed the cases in the wire fixation group. RESULTS: Follow-up was 16 +/- 11 months for the rigid fixation group and 20 +/- 12 months for the wire fixation group. Inferior movement at the anterior portion of the maxilla was 7.0 +/- 2.9 mm with rigid fixation and 4.5 +/- 3.6 mm with wire fixation (P < .05). Postsurgical superior movement (relapse) was 0.4 +/- 0.4 mm with rigid fixation and 2.4 +/- 2.4 mm with wire fixation (P < .01). Inferior movement at the posterior maxilla was 3.1 +/- 0.2 mm with rigid fixation and 2.8 +/- 2.3 mm with wire fixation. Postsurgical superior movement (relapse) was 0.8 +/- 0.4 mm with rigid fixation and 0.5 +/- 2.3 mm with wire fixation, which was not significantly different. CONCLUSION: This comparison showed downgrafting of the maxilla using autogenous bone harvested from the iliac crest and rigid internal fixation to be a predictable and stable procedure.

Adolescent↗