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PubMedDate not supplied

Dietary consistency and craniofacial development related to masticatory function in minipigs.

Since the 1890s oral biological researchers have been interested in the idea that strenuous mastication of unprocessed food will stimulate proper oral-facial growth and occlusal relationships. Conversely, lack of such function due to consumption of refined food is one hypothesis among many for the etiology of malocclusion in industrialized humans. Adequately controlled experimental testing of the idea has been limited to rats. To investigate the "disuse" theory in a larger-bodied and more occlusally relevant animal model, we raised four Yucatan minipigs from weaning on hard diet (HD) and another four on softened but equivalent diet (SD). The animals were monitored for eight months, sacrificed, and then occlusal and osteometric data collected. Variations due to dietary regime are pervasive and not due to caries, periodontitis, or attrition differences. Whereas HD body weight is 10% greater than SD, the deep masseter is 25% greater, with similar disproportion in superficial masseter and temporalis weight. Facial prognathism, arch narrowness, tooth crowding/maleruption and posterior cranial tapering are markedly different in the two groups. A curious posterior torsional difference in the mandibular rami, as well as broadness and flatness of the mandibular symphysis, also occur in SD. We performed a Q-mode principal coordinates analysis of the 19 logged variables for the specimens, bootstrapping the variable list, to demonstrate a statistically significant (P < .01) overall pattern of dramatic differences. Having controlled other celebrated orthodontic etiologies (genetic background, respiratory mode, infectious degeneration and interproximal attrition), these results support the proposition that dietary consistency relates directly to human craniofacial growth.

Animals↗
PubMedDate not supplied

Consequences of serious oral injury associated with the congenital analgia syndrome.

Three sisters at the ages of seven months, twelve years, and thirteen years presented with the initial damages to the oral tissues and the distinctive long-term effects in conjunction with the congenital analgia syndrome. The severity of this syndrome justifies the consideration of a prophylactic extraction of the primary dentition. A controlled mastication will be more likely with increasing age and eruption of the permanent teeth.

Adolescent↗
PubMedDate not supplied

Morphology of the mandibular condyle in "toothless" osteopetrotic (op/op) mice.

The defective bone resorption in the osteopetrotic op/op mouse brings about cranio-facial deformation and failure of tooth eruption. This study was conducted to elucidate the morphological changes of the condylar head and mandibular ramus in growing op/op mice. In normal mice, the condylar head is much broader than the ramus beneath it, enlargement and ossification of the condylar head begin after weaning, and the ramus becomes compact bone tissue. None of these changes were found in the op/op mice in the present observation. The condylar head was small, and its inner side was occupied by hypertrophic cartilage cells. In spite of the lack of bone resorption in op/op mice, the compaction of the mandibular ramus, which was composed of bone trabeculae, occurred later than that in normal mice. In view of recently studies reported evidence that local mechanical stress regulates the bone formation, we consider that undergrowth of the condylar head and the ramus in the op/op mouse results from not only a deficiency of osteoclasts but also insufficient mechanical stress from mastication.

Animals↗
PubMed1997

A study on the evaluation of masticatory ability in osseointegrated implants applied to lower molar region.

Masticatory function was investigated in 7 subjects (5 women and 2 men) with unilateral OIB in their lower molar region. Masticatory movement and myoelectric discharge were analyzed. To examine occlusal contact, the closely occlusal contact area and occluding forces were investigated. The results from the OIB side were compared with the ones from the opposite side. In all subjects, there were no significant differences in the parameters of mandibular movement between chewing the test foods on the OIB side and chewing them on the opposite side. In 6 out of 7 subjects, the closely occlusal area of the interocclusal space differed by less than 1.0 mm between the OIB side and the opposite side in the molar region, and the occluding forces between them were similar. In 6 out of 7 subjects, the masticatory sensations were also similar between the two sides. There were no significant differences between the OIB side and the opposite side in the parameters of mandibular movement, the condition of occlusal contact and the sensation of mastication in patients who were treated with unilateral OIB in the lower molar region. The data seem to suggest that there is little difference between the masticatory ability of OIB and that of natural dentition.

Adult↗
PubMed1998

[The evolution of the lower jaw and the jaw joint, from reptiles to man].

The evolution of the mandible shows two characteristic features: transformation of the angular, articular and square bones in reptiles into the tympanic bone, malleus and incus of the middle ear respectively; and specific volume expansion of the tooth-bearing bone which in mammals comprises the entire mandible. Posture, locomotion and mastication are the basic evolutionary factors which simultaneously provoked 1) a displacement of the temporal regions, 2) a transformation of the face lowering and widening the lower jaw and 3) an elongation of the sutures uniting the different bones in the reptile jaw bone, progressively leading to their separation and transversal orientation. These transformations were accentuated in the biped. Thus in man the temporomandibular joint is in a very lateral and elevated position near the mastoids. The mandibular condyls are elongated transversally with a medial cantilever. The medial part of the meniscus is drawn medially by the lateral pterygoid while the lateral part is drawn laterally by the temporal and masseter fibers. The ramus is oriented vertically and lies close to the cervical spine. The dental arches are displaced posteriorly on the bone and have lost their anterior abutment. The strongest occlusal forces are displaced to the posterior part of the arches and are transmitted vertically to the intra-articular meniscus. All these phenomena are termed extreme adaptations and the temporomandibular joint would (apparently) suffer if the evolution continued. The architectural features of temporomandibular joint overload can be deducted by comparison with the "ideal" architectural conditions for the craniofacial equilibrium.

Adaptation, Physiological↗
PubMedDate not supplied

Rehabilitation of patients with severely resorbed maxillae by means of implants with or without bone grafts. A 1-year follow-up study.

Forty-three patients with severely resorbed maxillae who had been referred for implant treatment were assigned to one of three treatment groups: bone grafting and implant placement (graft group); modified implant placement but no bone grafting (trial group); or optimized complete dentures (no-implant group). Sixteen, 20, and 7 patients, respectively, were assigned to the three groups. At the 1-year follow-up, 10% of the implants had been lost. Only a few of the failures (3/22) occurred after prosthesis placement. The cumulative success rates were 83% in the graft group and 96% in the trial group. A substantial reduction of the grafted bone, especially of the onlay grafts, occurred in many patients. During the period from prosthesis connection to the 1-year follow-up, marginal peri-implant bone loss was on average 0.5 mm. Despite the often demanding procedures involved, all but one patient in each implant group said that they would undergo the treatment again. Most patients were very satisfied with the treatment outcome and their improved masticatory ability. Those who had renounced implant treatment appeared modestly adapted to their optimized dentures, but reported retention problems and less satisfaction with mastication.

Adult↗
PubMedDate not supplied

The oral and maxillofacial surgeon's role in the care of patients with cleft lip and palate deformities.

Perhaps no conditions other than cleft lip and palate and oral cancer assemble teams of dentists and physicians intensely focused on treatment and rehabilitation. The oral and maxillofacial surgeon's role is often pivotal especially in the 20-year term of care for the child born with a cleft lip and palate deformity (CLPD). Issues of basic orofacial functions of mastication, respiration and communication overlay human considerations of self-esteem and image. From the moment of birth the child with a CLPD is special and challenged. Early issues concern parent and family acceptance and insuring basic life functions. While not generally a part of the immediate surgical unit, the OMFS often provides surgical consultation, educational and emotional support for the family. A clear picture must be painted of the treatment that will unfold over the next two decades. Realistic optimism is the watchword. Indeed, today there is every reason to anticipate an outcome that will result in a balanced, functional and esthetic face.

Adolescent↗
PubMed1998

Esthetic dentistry in the twenty-first century. Healthy beauty.

The goal of esthetic dentistry in the twenty-first century is to attain healthy beauty by harmonizing morphology and function. Morphologic beauty is achieved by using restorative techniques such as ceramo-metal restoration, all-ceramic restoration, laminate veneer, bleaching, and the treatment of malocclusion. Functional beauty is obtained by facilitating the primary functions of the stomatognathic organ, namely, mastication, speech, and craniomandibular stability. In the next century, esthetic dentistry must combine the present focus of morphologic beauty with the goals of functional beauty to attain true, healthy beauty.

Adult↗
PubMedDate not supplied

Radial forearm free flap for soft palate reconstruction.

Defects of the soft palate resulting from head and neck oncologic surgery traditionally have been rehabilitated using a prosthetic obturator. In general, the results of soft palate obturation have been satisfactory, with most patients achieving velopharyngeal competence during speech and swallowing. However, soft palate obturators have several disadvantages. Device stability and retention are impaired in patients who are edentulous. In addition, prosthetic obturators cover large areas of sensate mucosa in the hard palate, maxillary alveolus, and oropharynx, contributing significantly to the loss of sensory feedback from the oral cavity and oropharynx. Considerable evidence suggests that sensory impairment within the oral cavity and pharynx results in impaired mastication, deglutition, and articulation. A minority of patients find palatal obturators to be unsatisfactory, secondary to either inconvenience or device discomfort.

Forearm↗
PubMedDate not supplied

Hair-bearing temporoparietal fascial flap reconstruction of upper lip and scalp defects.

BACKGROUND: The temporoparietal fascial flap has proven to be a versatile flap for a broad spectrum of reconstructive problems in the head and neck. The temporoparietal fascial flap is a thin, pliable layer of richly vascularized tissue that may be transferred either pedicled or free and alone or as a carrier of subjacent bone or overlying skin and scalp. OBJECTIVE: To report our experience using a hair-bearing temporoparietal fascial flap for reconstruction in 6 male patients with extensive upper lip and scalp defects, including a discussion of the surgical anatomy and technique. METHODS: Temporoparietal fascial flaps with overlying scalp were used as pedicled and free flaps for the reconstruction of upper lip and scalp defects. RESULTS: All reconstructive results were satisfactory. Oral competence, measured by both speech and mastication performance, was achieved in patients with upper lip defects. Healthy scalp coverage was obtained in patients with local defects. The cosmetic appearance was satisfactory to all patients. CONCLUSIONS: Ideal reconstruction of large upper lip and scalp defects is achieved with local tissue that best mimics the normal face color, texture, and hair-bearing qualities. Hair-bearing temporoparietal fascial flaps possess these characteristics and are an excellent choice for the restoration of function and aesthetics.

Adult↗
PubMed1985

Dysphagia in Huntington's disease.

Dysphagia is a common complication of Huntington's disease (HD) that is frequently responsible for the potentially lethal respiratory events of aspiration or asphyxiation. Twelve patients who had HD and a history of dysphagia underwent extensive multidisciplinary clinical examinations. All of the patients, regardless of the clinical severity of their disease, demonstrated impaired control of many voluntary aspects of food intake that affected swallowing efficiency. Abnormalities of the rate of food consumption, mastication, bolus transfer, respiration, and swallow initiation seem to be responsible for most dysphagic symptoms in HD. Less prominent abnormalities of the pharyngoesophageal phases of ingestion were also noted. Dysphagia therapy was initiated in 11 of 12 patients. All of the patients' conditions improved; a majority (8/11) of the patients returned to an unrestricted diet. This improvement persisted for as long as three years, while other clinical features of HD intensified.

Adult↗
PubMed1998

Buccinator musculomucosal flap: applications in intraoral reconstruction.

OBJECTIVE: To evaluate the use of the buccinator musculomucosal flap in the reconstruction of defects of the oral cavity and oropharynx. DESIGN: Prospective case series of 8 patients during a 1-year period with an average follow-up of 1 year. Six anatomical dissections were performed on 3 fresh cadaver heads to investigate the neurovascular supply to the flap. SETTING: Academic tertiary referral medical center. RESULTS: The buccinator musculomucosal flap was used in the reconstruction of 8 defects of the oral cavity, retromolar trigone, and soft palate. There was 1 partial flap necrosis that occurred in a patient who had previously received radiation therapy and who healed secondarily without sequelae. No patient experienced difficulties with mastication or oral competence. All patients reported light single-point touch sensation over the flap 2 weeks after surgery. Cadaveric dissections using latex or india ink injections demonstrated the posterior neurovascular supply from the buccal artery, a branch of the internal maxillary artery, and the buccal nerve, a branch of the mandibular nerve. CONCLUSIONS: The buccinator musculomucosal flap is a dependable local sensate flap with a well-defined neurovascular pedicle that can be used in a variety of intraoral reconstructions obviating the need for distal tissue harvest.

Aged↗
PubMed2000

Reconstruction of the pediatric maxilla and mandible.

BACKGROUND: The creation of osseous defects in the upper and lower jaws in children is an uncommon occurrence. It is therefore likely that a head and neck reconstructive surgeon will accumulate only limited experience in restoring such defects. We have reviewed 7 pediatric bone-containing microvascular free flap reconstructions in 6 patients for reconstruction of the upper or lower jaws. Three patients were available for long-term follow-up to evaluate the effect of osseous free flap reconstruction on function and growth and development of the donor site. DESIGN: Retrospective review. SETTING: Academic tertiary referral center for otolaryngology. PATIENTS AND METHODS: Six pediatric patients ranging in age from 8 to 16 years underwent 2 fibular, 4 scapular, and 1 iliac free flap procedure for restoration of 2 maxillary and 5 mandibular defects from 1992 to 1997. Three of the 6 patients were available for long-term follow-up to assess the postoperative donor site function in an effort to determine the effect of this surgery on long-term donor site morbidity and development. RESULTS: Two patients were lost to follow-up, and 1 died secondary to complications related to distant metastatic disease. Three of 6 patients were observed for 2 years 6 months, 4 years, and 4 years 2 months, respectively. Two of the 3 patients who were observed long term have undergone full dental rehabilitation and currently maintain a regular diet and deny pain with mastication or deglutition. One patient did not require dental rehabilitation. All 3 patients demonstrate gross facial symmetry and normal dental occlusion. Assessment of the fibular donor site demonstrated normal limb length and circumference. The patients denied pain or restriction to recreational activity. Scapular donor sites demonstrated normal range of motion, strength, and shoulder stability. CONCLUSIONS: Free flap reconstruction of the pediatric maxilla and mandible requires harvesting bone from actively growing donor sites. We have found no evidence of functional deficit after bone harvest from the fibular or scapular donor sites. Patients demonstrate normal growth at the donor sites, and symmetry of the mandible and maxilla is preserved.

Adolescent↗
PubMed2000

The difficulties of diagnosing myositis ossificans circumscripta in the paraspinal muscles of a human immunodeficiency virus-positive man: magnetic resonance imaging and temporal computed tomographic findings.

Myositis ossificans circumscripta (MOC) is an uncommon disease that has been reported to develop after trauma, burns, and infections, as well as in cases in which the pathogenesis is unknown. Although most cases of MOC develop below the clavicles, it has been reported in the head and neck area, where it primarily involves the muscles of mastication. To our knowledge, there have been only 4 previous reports of MOC affecting the paraspinal muscles. We report the fifth such case, which developed in a human immunodeficiency virus-positive patient, and describe the longitudinal imaging changes of MOC.

Adult↗
PubMed1978

Facial rehabilitation with temporal muscle. New concepts.

Facial rehabilitation, utilizing the transposed temporalis muscle, was performed. Three new innovations of this technique include: (1) The whole muscle is transposed into the face to accomplish augmentation, support, protection for the eye, and movement. (2) Following transposition of the temporalis muscle, its nerve supply is lysed at the foramen ovale. Nerve substitution by a free, autogenous graft from the proximal segment of the ipsilateral facial nerve or crossfacial sural nerve is accomplished. This technique substitutes the facial nerve axons and nuclei for the trigeminal nerve in this muscle and thus eliminates movement on mastication and facilitates the possibility for expression. (3) This muscle may be transposed with a portion of the temporal and parietal bones to add bony architecture to the cheek and orbit.

Facial Muscles↗
PubMed1978

Prosthetic functional therapy. A new method for rehabilitation of the orally handicapped patient.

A new approach to the rehabilitation of individuals who are orally handicapped after surgery offers direct support to dysfunctioning oral musculature, as well as physiologic conditioning to redirect tongue posture. Prosthetic functional therapy can be used to improve problems of speech, swallowing, drooling, and mastication in cases where structural loss of neuromuscular impairment have affected the functional competence of oral tissues. Patients who experience this therapy become highly motivated to succeed in rehabilitation as a result of a positive feedback that is provided by improvement in functional competence. Patients express both satisfaction and comfort and tend to progress favorably in the course of therapy.

Adult↗
PubMed1980

Composite resection and reconstruction for oral cavity and oropharynx cancer. A functional approach.

Composite resection, the standard surgical approach for treating cancer of the oral cavity and oropharynx, results in considerable functional and cosmetic deformity, whether primary closure or flap reconstruction is employed. To minimize these problems, an alternate surgical approach has been developed. Essentials of the procedure include use of a non-lip-splitting visor flap for exposure and excision of the lesion, reconstruction with a skin or dermis graft formed into a pouch to fill dead space created by resection, and routine use of intermaxillary fixation for immobilization of the reconstructed area. In 16 patients undergoing this procedure, the approach had no adverse effect on short-term survival. Complication rate with skin and dermis graft reconstruction was acceptably low. Cosmetic improvement has been gratifying. Skin or dermis graft reconstruction has resulted in very satisfactory functional results in terms of tongue mobility, articulation, mastication, and swallowing.

Aged↗
PubMed1983

Mandibular reconstruction using implantable stabilization plates.

The consequences of substantial mandibular loss usually are disturbances in mastication and often in cosmesis. In an attempt to arrive at an easy and reliable technique of reconstructing mandibular defects, a selected group of patients were treated using rigid, implantable reconstruction plates. These were used to provide continuity and stability for the residual mandible with or without the use of graft materials. These have included autogenous fresh, irradiated, or frozen bone, and polytetrafluoroethylene carbon fiber sponge (Proplast). A discussion of the principles and technique of using reconstruction plates is outlined.

Aged↗