Preprosthetic surgery for the edentulous patients.

Preprosthetic surgery is a rapidly changing area of dentistry. A knowledge of the range, capabilities, and limitations of the commonly used surgical procedures is a must for anyone treating a patient who will receive a complete denture prosthesis. It cannot be overemphasized that the establishment of a clear treatment plan and close coordination of all parties involved in the reconstructive effort are essential to achieve the best overall result.

Photoluminescence and optical absorption of Cs2NaScF6:Cr3+.

The main objective of this paper is the characterization of the spectroscopic properties of new materials that are prospective laser media. This approach allows for the comparison of the properties of the Cr3+ in different environments. Here, we have studied the photoluminescence and optical absorption of Cs2NaScF6:Cr3+ single crystals. On the basis of near-infrared luminescence measurements at 2, 77, and 300 K the observed lines originated from the Cr3+-centres were associated with the 4T2(4F) --> 4A2(4F) transition and the lifetimes were obtained. In spite of the quenching observed as a function of temperature at least 10% of the 2 K emission intensity for Cs2NaScF6 doped with 1% of Cr3+ remains at room temperature. Besides, the 2 K emission broad band could be well described in terms of normal modes of the octahedral complex [CrF6]3-, and the Racah and crystal-field parameters calculated.

Preoperative nutritional supplementation for the orthognathic surgery patient.

Orthognathic surgery patients were studied to determine the nutritional adequacy of a high-calorie liquid supplement. The supplements were given for one month before surgery in an attempt to achieve a 5% weight gain and/or for six weeks after surgery to approximate 50% of the estimated caloric requirements of the patients. It was concluded that preoperative supplementation to achieve weight gain before surgery is of no apparent value. However, balanced nutrient intake can be achieved for patients when supplementation is given postoperatively at a level of 50% of estimated caloric requirements, and can result in improved nitrogen retention and protein sparing.

A cephalometric evaluation of American Negro women.

A cephalometric study of forty American Negro women with an average age of 24.6 years and a Class I molar and/or canine relationship was performed. When measurements were compared to a control population of twenty Caucasian women, using several standard analyses, significant differences were demonstrated between the sample populations. 1. The maxilla and mandible were more protrusive in the Negro sample. 2. The upper and lower incisors were more proclined and the interincisal angle was more acute in the Negro sample. 3. Middle facial height was shorter and lower facial height was longer in the Negro sample. 4. The projection of the soft-tissue nasal tip was less in the Negro sample. 5. The projection of the upper and lower lips as related to the facial plane was greater in the Negro sample. 6. Lip thickness was approximately the same in the two groups.

Treatment of chronic drooling: a preliminary report.

Chronic drooling can be both psychologically and physically damaging. The technique of sialodochoplasty with sublingual gland resection is a viable treatment modality for this problem. The results of a series of eight patients who underwent the procedure are reported. A short-term success rate of 75% was achieved without morbidity.

The effect of antenatal surgery on postnatal palatal growth in sheep.

It has been suggested that repair of skin and mucosal wounds carried out in animals in utero leaves little or no trace of the operative procedure when examined at birth. This study examined the palates of lambs affected surgically in utero postnatally for scarring and transverse palatal growth. Nineteen pregnant sheep were affected at 120 days gestation. Surviving lambs followed for 6 months demonstrated altered palatal morphology.

Technetium bone imaging as an adjunct in the management of fibrous dysplasia.

The diagnosis of fibrous dysplasia is one that is often made on the basis of biopsy findings and routine radiographs of involved areas. Until the advent of total body scanning, early cases of polyostotic fibrous dysplasia went undiagnosed until swelling, asymmetry, or deformity was noticed in other body parts. More sensitive radiographic techniques, (this is, bone imaging) are now available which offer a means for early detection of polyostotic involvement and more accurate delineation of lesions of the monostotic variety.

Single arch stabilization devices for segmental orthognathic surgery.

Single arch stabilization of segmental osteotomies is desirable because it eliminates intermaxillary fixation while it, in turn, improves oral hygiene and communication and patient comfort, function, and acceptability. Orthodontic appliances with stabilizing arch wires are the method of choice if available. Arch bars modified for segmental stabilization function very well as an alternative to orthodontic appliances. Cast splints are also useful for these cases, although cost and the need for expert laboratory support limit their acceptability. Certain other devices, such as palatal and lingual plates and interocclusal wafers, provide additional support for several of the above-mentioned stabilization systems.

Healing of interpositional allogeneic lyophilized bone grafts following total maxillary osteotomy.

Healing of allogeneic lyophilized bone grafted to total maxillary osteotomy sites was studied in Macaca fasciularis monkeys using histologic, microangiographic, and autoradiographic methods. Results of the study indicate that allogeneic lyophilized grafts are slowly replaced by host bone. Revascularization around the margins of the graft becomes evident at two weeks and increases until eight weeks; a hypervascular response is still present at six months. The palatal mucosa and facial gingiva provide an adequate nutrient pedicle for interpositional allogeneic grafts.

The transmandibular implant: implant reconstruction and rehabilitation for the atrophic mandible.

The transmandibular implant is specifically designed for the reconstruction and rehabilitation of the severely atrophic mandible utilizing an extraoral approach. The unique design and surgical protocol of the transmandibular system have proven to be predictable and successful. The indications, implant design and materials, surgical technique, advantages, and disadvantages of the transmandibular system are presented in this article.

A retrospective study of alveolar cleft grafting.

A surgical technique for the bone graft repair of alveolar clefts is described, and an evaluation of the conditions of 30 patients who have undergone that procedure is reported. Evaluation was made specifically for the preoperative and postoperative presence of oronasal fistula, postoperative eruption of previously unerupted teeth into the graft, soft and hard tissue periodontal status, and radiographic evidence of bone fill in the previous cleft defect resulting in alveolar segmental stabilization.

Postoperative nutritional supplementation for the orthognathic surgery patient.

Twenty-four orthognathic surgery patients were studied to determine the impact of a high-calorie liquid supplement on preventing or minimizing catabolism commonly associated with surgery. The experimental group of 12 subjects, chosen at random, consumed blenderized foods ad libitum and a high-calorie dietary supplement providing a minimum of 50% of energy requirements. The remaining 12 subjects consumed only blenderized foods and served as the control group. The nutritional status of all patients was assessed one day before surgery and on Day 7 of the first, third, and sixth postoperative week. In general, nutrient intake in the experimental group remained similar to that before surgery, whereas intake in the control group decreased significantly, particularly at the one-week postoperative evaluation. It was concluded that the addition of a high-calorie liquid supplement to the dietary regimen of orthognathic surgery patients helped maintain nutrient intake at a level comparable to that before surgery. This resulted in better maintenance of body weight and somatic protein compartments compared with the control group.

Soft tissue changes associated with total maxillary advancement: a preliminary study.

A retrospective investigation was performed with use of cephalometric radiographs from eight patients with anterior maxillary advancement. Soft tissue changes associated with hard tissue changes were measured. Statistical description of soft tissue behavior in the upper lip was performed using correlation coefficients, regression functions, and ratios of change in the relationship of soft tissue to hard tissue. Ratios of change in relationship of soft tissue to hard tissue for three parameters of upper lip movement are proposed for clinical use in treatment planning. Further investigation of soft tissue behavior with orthognathic surgical procedures is indicated.

Stability of simultaneous maxillary intrusion and mandibular advancement: a comparison of rigid and nonrigid fixation techniques.

This study examines the short-term stability of bimaxillary surgery following Le Fort I impaction with simultaneous bilateral sagittal split osteotomies and mandibular advancement using two standard techniques of postsurgical fixation. Fifteen adults had skeletal plus dental maxillomandibular fixation, and fifteen adults had rigid internal fixation using bone plates in the maxilla and bicortical bone screws between the proximal and distal segments in the mandible. The group with rigid internal fixation did not undergo maxillomandibular fixation. Radiographic cephalograms were analyzed during the postsurgical period to evaluate skeletal and dental stability. There was no statistical difference in postsurgical stability with rigid internal fixation or skeletal plus dental maxillomandibular fixation other than the vertical position of the maxillary molar; the skeletal plus dental maxillomandibular fixation group had a significant amount of postsurgical intrusion of the maxillary molar when compared with the rigid internal fixation group. Although the other measures showed no statistically significant difference between the experimental groups, the amount of variability in postsurgical stability in the group with skeletal plus dental maxillomandibular fixation was greater than that found in the group with rigid internal fixation.

Particulate allogeneic bone grafts into maxillary alveolar clefts in humans: a preliminary report.

The purpose of this study was to determine the ability of particulate allogeneic bone graft to adequately bridge unilateral maxillary alveolar clefts in humans. Twenty patients with unilateral alveolar clefts and oronasal fistula underwent alveolar cleft grafting with a clinically appropriate amount of particulate allogeneic bone. The grafted cleft area was followed radiographically for three to six months postsurgery. Although it was difficult to quantitate, it was both clinically and radiographically apparent at three months that bone bridging and filling of the cleft had occurred in 100% of the cases. From this study, it appears that allogeneic bone is a viable alternative for repairing alveolar clefts and that its use has a significant benefit to the patient by eliminating the morbidity of a second operative site.