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At least 163 records · Page 9Linked to original sources
PubMed1992

Spark erosion fixed/detachable prosthesis for the completely edentulous maxilla.

A technique is described for restoration of the completely edentulous maxilla. From six to eight root-form implants are surgically placed in the edentulous maxilla. A hybrid overdenture is constructed by use of a two-degree tapered precision milled primary bar. A cast overdenture prosthesis is constructed over this bar, and precision attachments are spark-erosion-processed to the primary and secondary prosthetic components. The technology described in this article allows for an intimate fit of the various prosthetic components. This prosthetic protocol permits maximum retention and stability of the prosthesis and solves many problems which are encountered in the oral rehabilitation of the edentulous maxilla.

Adult↗
PubMed2003

The maxillae: integrated and applied anatomy relevant to dentistry.

The union of the two paired maxillae form the whole upper jaw. Individual components of the maxilla contribute to the formation of the face, nose, mouth and orbit. The bony surfaces are in relation to the infratemporal and pterygopalatine fossae. Grooves, openings and foramina lend passage to structures such as the infra-orbital, posterior superior alveolar, nasopalatine and greater palatine nerves. These nerves are of great importance for regional anaesthesia in dentistry. The maxillary antrum of Highmore is frequently affected by pathological processes such as accidental tooth root impaction during an extraction procedure, sinusitis, cysts, fractures (LeFort) and tumours. Fast-growing maxillary sinus tumours often breach the thin walls of this cavity and encroach upon adjacent structures such as the orbit, nose, cheek, infratemporal fossa and mouth. 'Blow-out' fractures through the orbital component may result in nerve and muscle entrapment. Alveolar processes form an arcade for the two incisors, one canine, two premolars and three molars on each side. Knowledge of regional and applied anatomy, relevant to the maxillae, is essential when considering diagnostic imaging by X-rays, CT, and MRI.

Alveolar Process↗
PubMed2004

Outcome analysis of implant restorations located in the anterior maxilla: a review of the recent literature.

PURPOSE: To document the literature regarding outcomes of implant restorations in the anterior maxilla to formulate consensus statements with regard to esthetics in implant dentistry, to provide guidelines to clinicians, and to articulate remaining questions in this area to be addressed by future research. MATERIALS AND METHODS: The following areas of the recent literature were scrutinized: treatment outcomes of implant therapy for partial edentulism (including maxillary anterior tooth replacement); anterior maxillary single-tooth replacement; effect of implant design, diameter, and surface characteristics; soft tissue stability/contours around anterior implant restorations; ceramic abutments; influence of surgical techniques; and finally, evaluation of patient satisfaction. RESULTS: The use of dental implants in the esthetic zone is well documented in the literature, and numerous controlled clinical trials show that the respective overall implant survival and success rates are similar to those reported for other segments of the jaws. However, most of the published studies do not include well-defined esthetic parameters. Currently, the literature regarding esthetic outcome is inconclusive for the routine implementation of certain surgical approaches, such as flapless surgery and immediate implant placement with or without immediate loading/restoration in the anterior maxilla. Considering anterior single-tooth replacement in sites without tissue deficiencies, predictable treatment outcomes, including esthetics, can be achieved because of tissue support provided by adjacent teeth. The replacement of multiple adjacent missing teeth in the anterior maxilla with fixed implant restorations is poorly documented. In this context, esthetic restoration is not predictable, particularly regarding the contours of the interimplant soft tissue. DISCUSSION AND CONCLUSIONS: This review has demonstrated that scientific documentation of esthetically relevant and reproducible parameters is rather scarce. Most of the reported outcome analyses primarily focus on implant survival. Elements of anterior implant success such as maintenance or reestablishment of harmoniously scalloped soft tissue lines and natural contours should be included in future studies.

Dental Abutments↗
PubMedDate not supplied

Immediate versus delayed loading of dental implants in the maxillae of minipigs: follow-up of implant stability and implant failures.

PURPOSE: To assess the course of the stability and the failure rate of dental implants placed in the partially edentulous maxillae of minipigs. MATERIALS AND METHODS: Three months after tooth removal, implants were placed in 9 minipigs. Six implants (XiVE; Friadent, Mannheim, Germany) were placed on each side of the posterior maxilla after preparation of the implant sites either by an osteotome technique or with spiral drills. Implant stability was assessed by resonance frequency analysis (RFA) at the time of placement, at second-stage surgery (which took place after a healing periods of 1, 2, 3, 4, or 5 months), and after a loading period of 6 months. RESULTS: Implant stability was significantly influenced by the healing period (P = .007). Implant stability decreased after 1 to 3 months of healing for both of the placement techniques and increased after a healing period of 4 months. After implant site preparation by an osteotome technique, 6 of 12 immediately loaded implants, 18 of 24 implants loaded after healing periods of 1 to 3 months, and 1 of 18 implants loaded after a healing period of 4 or 5 months were lost. After implant site preparation using spiral drills, 7 of 12 immediately loaded implants, 12 of 24 implants loaded after healing periods of 1 to 3 months, and 2 of 18 implants loaded after healing periods of 4 or 5 months were lost. Broad overlapping of confidence intervals for the number of implant failures revealed that there was no relevant difference between immediate and early functional loading for either of the 2 techniques. DISCUSSION AND CONCLUSION: Implant loading after healing periods of 1 to 3 months did not improve implant survival compared to immediate loading in the posterior maxillae of minipigs. Not until a healing period of 4 months was reached did implant stability begin to increase. Only when functional loading was started at this point in time was maximal implant survival achieved.

Analysis of Variance↗
PubMedDate not supplied

Immediate versus delayed loading of dental implants in the maxillae of minipigs. Part II: histomorphometric analysis.

PURPOSE: To assess histomorphometric parameters of dental implants placed in partially edentulous maxillae of minipigs. MATERIALS AND METHODS: In 9 minipigs, 6 XiVE implants were placed on each side of the maxilla, either after implant site preparation by an osteotome technique or by spiral drills. The implants were restored with fixed provisional restorations and loaded either immediately or after healing periods of up to 5 months. After a loading period of 6 months, the animals were sacrificed and the implants were retrieved together with the adjacent bone. Histologic specimens were prepared and bone-to-implant contact (BIC) ratio, interthread bone area, and peri-implant bone area were determined. RESULTS: An analysis of variance revealed that the BIC ratio on the palatal side was significantly influenced by the preparation technique of the implant site (P = .001) and by the healing period (P = .02). After implant site preparation by an osteotome technique, higher BIC values were achieved for implants that were loaded either immediately or after healing periods of 1 to 3 months. After healing periods of 4 to 5 months, implant site preparation with spiral drills showed slightly better results in regard to BIC. Interthread bone area and peri-implant bone area did not differ significantly statistically for the 2 implant placement techniques and the 3 healing periods. DISCUSSION AND CONCLUSION: After 6 months of functional loading in the maxilla, successful immediately loaded implants performed the same as implants subjected to an unloaded healing period prior to loading as far as histomorphometric data were concerned. Prospective randomized clinical studies should be carried out in humans to compare immediate loading to loading after an unloaded healing phase.

Analysis of Variance↗
PubMed2005

[Nasal septal abscess and palatine process of the maxilla abscess complicating acute rhinosinusitis in a 12-year old boy].

We report a case of nasal septal abscess and palatine process of the maxilla abscess secondary to acute rhinosinusitis in an 12-year-old boy. Rare complication of acute sinusitis is the nasal septum abscess; even rarer is the abscess of the palatine process of the maxilla, which our patient presented. Nasal septum abscess is an reservoir of suppurative secretion between cartilage or bone of the septum and their periostium or perichondrium. Nasal septum abscess is most often bilateral, causing nasal cavities obstruction. Other symptoms are: nasal pain, fever, headache, nasal tenderness, bad general feeling. Spontaneous abscesses of nasal septum are rare and occur due to acute ethmoid or sphenoid sinusitis and inflammations originating from teeth. Patophysiology of nasal septum abscess depends on its etiology. The isolated acute sphenoid sinusitis may lead to occurrence of nasal septum abscess by spreading of inflammatory changes under periostium along the anterior surface of sphenoid bone and damaging the periostium of vomer and perpendicular lamina of ethmoid bone into subperichondrial space of quadrangular cartilage. Inflammation of inferior wall of sphenoid sinus located over fornix of nasopharynx might have lead to appearance of the palatine process of the maxilla abscess. We consider this mechanism of abscess creation occurred in our patient. Another possible mechanism comprehends spreading of inflammatory process through bone fissures, congenital bone malformations of due to thrombophlebitis. Recommended procedure in cases of confirmed nasal septum abscess is surgical decompression from semitransverse incision of the column and abscess drainage. Aspiration and bacteriological culture allow for exact establishment of proper antibiotic treatment. Antibiotic therapy should be conducted for 2-3 weeks according to bacterial sensitivity to chemotherapeutics. In reexamination of our boy's nasal septum cavity of abscess was assessed and a small cartilage defect was noted. Necrotic changes in nasal septum cartilages arise due to ischemia and compression by residual pathological contents between perichondrium and cartilage. Proper recognition and surgical and preservative treatment lead to total recovery. In our boy, control examinations after 2 and 6 months confirmed recovery without recurrence and later complications.

Acute Disease↗
PubMed2006

Treating the atrophic posterior maxilla by combining short implants with minimally invasive osteotome procedures.

Edentulous sites in the posterior maxilla are often compromised by reduced bone volume, prohibiting the placement of 10-mm implants without sinus augmentation. The use of shorter implants minimizes the need for more extensive sinus floor elevation, thus reducing treatment duration and morbidity. Two implant designs are presented in combination with localized internal sinus floor elevation to restore the posterior maxilla. This simplified treatment modality can make implant rehabilitation of the atrophic posterior maxilla more accessible and more palatable to even the most reluctant patients and referring doctors.

Adult↗
PubMedDate not supplied

Immediate function with the zygomatic implant: a graftless solution for the patient with mild to advanced atrophy of the maxilla.

PURPOSE: In many edentulous maxillae, posterior alveolar atrophy calls for bone grafting. Patient treatment acceptance is increased by eliminating grafting using tilted implants, especially the zygomatic implant in combination with immediate function. The purpose of this study was to evaluate a protocol for immediate function (within 2 hours) of 2 zygomatic and 4 standard implants (Nobel Biocare) supporting a fixed prosthesis in the completely edentulous maxilla. MATERIALS AND METHODS: This clinical study included 14 patients with 83 immediately loaded implants (28 bilateral zygomatic and 55 premaxillary implants) supporting a complete maxillary denture converted to a fixed provisional prosthesis immediately following the surgical procedure. After 6 months of use, a new fixed metal-supported prosthesis was fabricated. RESULTS: Fourteen patients treated with immediate loading of zygomatic implants were followed for at least 12 months. All patients reported minimization of postoperative pain and security during speech, animation, and mastication. No failures occurred during the follow-up period. DISCUSSION: The patients in the study could have been candidates for sinus grafting. With the present concept these patients benefited from a less invasive procedure (1 surgical procedure and no grafting) and immediate rehabilitation (prosthesis attached directly after surgery). CONCLUSION: The high survival rate, increase in patients' immediate functional ability, and reduction of morbidity following the surgical procedure render this procedure a viable treatment option for the completely edentulous maxilla.

Atrophy↗
PubMed1991

Biomechanical analysis of osseointegration of IMZ implants in goat mandibles and maxillae.

This study was designed to determine the effect of time on the biomechanical integration of cylindrical dental implants in the mandible and maxilla. A total of 136 IMZ dental implants was placed bilaterally in the endentulous maxillae and mandibles of 17 goats. Pullout tests were used to assess biomechanical integration at intervals from 2 to 24 weeks. This study indicated that there is a time-dependent, progressive increase in pullout force to 24 weeks. The forces were consistently higher for the mandible than the maxilla. Moreover, there was no correlation between the intraoperative stability of the implant and the postoperative pullout force.

Animals↗
PubMed1989

[Changes in the nasal pyramid in osteotomy of the maxilla].

The correction of dento-facial deformities with Lefort I osteotomy are always accompanied by changes in soft tissue and skeleton. But, in many cases there is also modification of the low floor of the nose and profile changes. This clinical experience has been confirmed in the Laboratory on cadavre experimentation. Three deplacements have been studied: advancement of maxilla, inferior repositioning of maxilla and superior repositioning of maxilla. Often, Lefort I osteotomy is a complex association of these movements; modifications are also function of soft tissue. Operation must necessary provide theses technical modification for a real adaptation of the surgery. The surgical technique must therefore be adapted in order to obtain the best aesthetic result.

Cadaver↗
PubMed1986

Stability of the maxilla after Le Fort III advancement in craniosynostosis syndromes.

The purpose of this study was to assess long-term position of the maxilla after surgical Le Fort III advancement of midfacial structures in patients with craniosynostosis syndromes. Data from preoperative, short and long-term postoperative lateral head films on 21 consecutive patients with Crouzon's syndrome, Pfeiffer's syndrome, or Apert's syndrome were analyzed. A method of evaluating the position of the postoperative maxilla on lateral head films is described. On average, the position of the maxilla did not change significantly in the postoperative periods studied, although some individual variation was demonstrated. Postoperative management, utilizing a registration bite splint after the intermaxillary fixation has been removed, similar to our treatment following bone grafting procedures in patients with hemifacial microsomia, is described.

Acrocephalosyndactylia↗
PubMed1987

Extraoral traction to the maxilla with face mask: a follow-up of 17 consecutively treated patients with and without cleft lip and palate.

Lateral cephalometric films of seven cleft palate (CP) or unilateral cleft lip and palate (UCLP) and ten nonCLP patients were obtained immediately before extraoral traction with face mask, immediately after, and at 6 months follow-up. The mean age at start of treatment was 7 years for the CLP patients and 11 years for the nonCLP patients. The average duration of traction was 8 months in both groups. The traction force was gradually increased from 300 to 800 g on each side. Five angular measurements were defined and recorded. The mean net effect in anterior displacement of the maxilla in the CLP group was +0.2 degrees (range +2.5 degrees to -2.5 degrees) and in the nonCLP group +1.0 degree (range +2.5 degrees to -1.0 degree). The orthopaedic effect of extraoral traction to the maxilla was found to be independent of skeletal morphology, age, peak height velocity (PHV), and duration of traction, and thus to be unpredictable. Normal overjet was obtained in most patients, because of a combination of anterior displacement of the maxilla, posterior displacement of the mandible, tipping of the incisors, and a possible anterior sliding of the maxillary dental arch on its base.

Adolescent↗
PubMed1980

The genesis of membrane bone in the embryonic chick maxilla: epithelial-mesenchymal tissue recombination studies.

In the present study, the question of whether a relatively non-specific epithelial requirement exists for membrane bone formation within the maxillary mesenchyme was investigted. Organ rudiments from embryonic chicks of three to five days of incubation (HH 18-25) were enzymatically separated into the epithelial and mesenchymal components. Maxillary mesenchyme (from embryos HH 18-19) which in the absence of epithelium will not form bone was recombined with epithelium from maxillae of similarly aged embryos (homotypic-homochronic recombination) and of older embryos (HH 25) (homotypic-heterochronic recombination). Heterotypic recombinations were made between maxillary mesenchyme (HH 18-19) and the epithelium from wing and hind-limb buds (HH 19-22). Recombinants were grown as grafts on the chorioallantoic membranes of host chick embryos. Grafts of intact macillae, isolated maxillary mesenchyme, and isolated epithelia from the maxilla, wing-, and hind-limb buds were grown as controls. The histodifferentiation of grafted intact maxillae was similar to that in vivo; both cartilage and membrane bone differentiated within the mesenchyme. Grafts of maxillary mesenchyme (from embryos HH 18-19) grown in the absence of epithelium formed cartilage but did not form membrane bone. Grafts of maxillary mesenchyme (from embryos HH 18-19) recombined with epithelium in homotypic-homochronic, homotypic-heterochronic, and heterotypic tissue combinations formed membrane bone in addition to cartilage. These results indicate that maxillary mesenchyme requires the presence of epithelium to promote osteogenesis and that this epithelial requirement is relatively non-specific in terms of type and age of epithelium.

Animals↗
PubMed1994

Stability following superior repositioning of the maxilla by Le Fort I osteotomy: five-year follow-up.

Changes in dental and skeletal relationships were evaluated 5 years postsurgically in 49 patients whose maxilla had been superiorly repositioned by a Le Fort I osteotomy. All of the patients had at least 2 mm of intrusion at the maxillary incisor and molar; none had a mandibular ramus osteotomy or other osteotomy except genioplasty. Only 6.5% had 2 mm or greater of net vertical change in skeletal or dental landmarks at 1 year postsurgery. From 1 to 5 years postsurgery, minimal changes in skeletal and dental landmarks occurred in the majority of the patients, but approximately 25% of the patients showed 2 mm or more of downward movement of the maxilla and/or eruption of maxillary teeth, leading to downward-backward rotation of the mandible. Only one patient had more than 1 mm of open bite on long-term follow-up. An increase in overbite, resulting from incisor eruption, was noted in 14%, and an increase in overjet occurred in 12% as the mandible rotated. It appears that modest long-term skeletal and dental changes occur in some surgically treated long-face patients. The likelihood of long-term change was not related to the age of the patient, stability during the first postsurgical year, or segmentation of the maxilla at surgery.

Adolescent↗
PubMed1993

[Arterial distribution and morphogenesis of human maxilla].

There are two leading hypotheses concerning maxillofacial morphogenesis in human (Fusion Hypothesis & Overlapping Hypothesis). Differing opinions about the maxillary morphogenesis lead to different concepts about the intrinsic arterial supply to the maxilla. This research was to study the arterial constitution of human maxilla so as to inquire into its morphogenetic patterns. Appropriately perfused (Pb3O4 + turpentine) infraorbital and posterior superior alveolar arteries in 9 fresh human cadavers with ages ranging from 2 days to 35 years revealed that 4 individuals' arterial systems of maxilla consisted of anterior and posterior superior alveolar arteries, but the other 5 ones consisted only of the posterior superior alveolar artery, which extending to the facial midline and supplies all the incisor and molar teeth. The results indicated that two kinds of maxillary morphogenesis patterns may exist simultaneously.

Adult↗
PubMed1993

The implant-supported overdenture prosthesis for the edentulous maxilla.

Restoration of the edentulous maxilla with endosseous implants and a fixed prosthesis can be difficult. Problems encountered may include inadequate available bone, deficient lip support, and poor esthetics and phonetics. A palateless maxillary implant-supported overdenture has been shown to be useful in solving these problems. Four endosseous implants were placed in the anterior maxilla of a 59-year-old patient and allowed to osseointegrate for six months. After second-stage surgery was completed, a mesostructure bar incorporating ERA attachments was fabricated along with a palateless overdenture. This type of prosthesis offered a solution to the moderate to severely atrophic maxilla for a patient who was unable to tolerate a conventional prosthesis.

Alveolar Bone Loss↗
PubMedDate not supplied

A modified method of simultaneous bone grafting and placement of endosseous implants in the severely atrophic maxilla.

The purpose of this investigation was to clinically evaluate the modified method for surgical rehabilitation of severely atrophied maxillae with titanium implants. In 35 patients, sinus lift, Le Fort I osteotomy, and a downtilting of the maxilla were performed. Bone grafts from the iliac crest, placed between the sinus mucosa and the sinus floor, were secured with three to four Bränemark titanium implants 10 to 20 mm in length on each side. The osteotomized maxilla was stabilized with miniplates. The observation period was between 1 and 4 years after abutment connection. The rate of successful osseointegration was 86.6%.

Adult↗
PubMed1984

Plexiform ameloblastoma of the maxilla with extension to the skull base.

Ameloblastomas are locally invasive benign tumors believed to originate from the developing dental lamina. Maxillary ameloblastomas are rare, comprising only 20% of all ameloblastomas. Of these, 90% arise posterior to the canine tooth. As tumors of the posterior maxilla grow slowly, symptoms are few until the tumor has reached considerable size. At the time of presentation there may be evidence of extension into anatomic areas adjacent to the posterior maxilla. Hemimaxillectomy through wide surgical exposure has the best chance of achieving tumor control. However, once the tumor has extended beyond the confines of the maxilla the prognosis for control of the disease is poor.

Ameloblastoma↗