PubMed Health⌕ Search

Biomedical subjects

K W Vig

Publications and source records attributed to K W Vig.

At least 37 records · Page 2Linked to original sources
PubMed1993

Changes in the nasal and labial soft tissues after surgical repositioning of the maxilla.

Accurate prediction of postsurgical function and esthetics of the nose and upper lip requires an understanding of the relationship between maxillary surgical movement and soft tissue change. Thirty-two patients underwent Le Fort I osteotomies, some with concomitant mandibular procedures. Preoperative, postoperative, and 1-year postsurgical data derived from cephalometric and nasolabial cast analysis were compared to assess skeletodental changes, soft tissue changes, and stability. A multiple stepwise regression (including age, gender, alar cinch suture, V-Y closure, and contouring of the anterior nasal spine as variables) indicated that accurate prediction equations could be formulated, particularly if the patients were grouped by vector-specific maxillary movements. In general, the base of the nose widened in all patients regardless of the vector of surgical maxillary movement. An associated shortening of the nose was found. The nasolabial angle decreased or remained constant in most patients. The upper lip widened and lengthened at the philtral columns. Narrow noses widened more than did broad noses and alar cinch suturing widened the alar base even more. Results indicated that soft tissue changes associated with maxillary surgery may be more affected by the position of the soft tissue incision and methods used in closure than by the surgically induced hard tissue change.

Adolescent↗
PubMed1992

The Dentofacial Deformity Program of the University of Michigan: organization, analysis of data, and benefits of program.

The Dentofacial Deformity Program of the University of Michigan was established in 1984 to provide a consulting service for the diagnosis, treatment recommendations, and management of patients with dentofacial deformities. This program was designed as a service commitment for the patient, referring doctors, and the medical and dental communities. Educational and research aspects of the program provide benefits for orthodontic and oral and maxillofacial surgery graduate students, and the dental school faculty. The organization, data analysis, and education, research, and service benefits of this program are discussed.

Adolescent↗
PubMed1991

Consistency of orthodontic treatment decisions relative to diagnostic records.

The purpose of this study was to evaluate how incremental information obtained from different types of diagnostic records contributes to the determination of orthodontic treatment decisions. Pretreatment records of 57 orthodontic patients were assessed by five orthodontists who were part-time faculty members and also in private practice. This sample consisted of dental school orthodontic patients who had Class II malocclusions and included patients at three different dental developmental stages. The following diagnostic records were used: study models (S), facial photographs (F), a panoramic radiograph (P), a lateral cephalogram (C), and its tracing (T). Five combinations of diagnostic records were presented to the orthodontists in the following sequence: (1) S; (2) S + F; (3) S + F + P; (4) S + F + P + C; and (5) S + F + P + C + T. The simultaneous interpretation of all diagnostic records (S + F + P + C + T) was used as the "diagnostic standard." There was a diagnostic standard for each of the patients and for each of the orthodontists. The diagnostic standard was achieved: (1) S = 54.9%, (2) S + F = 54.2%, (3) S + F + P = 60.9%, and (4) S + F + P + C = 59.9%. Thus, in a majority of cases (55%), study models alone provided adequate information for treatment planning, and incremental addition of information from other types of diagnostic records made small differences.

Adult↗
PubMed1990

Allogeneic bone for secondary alveolar cleft osteoplasty.

The purpose of this retrospective clinical study was to determine the efficacy of allogeneic bone for secondary alveolar cleft osteoplasty. Twenty-four patients with unilateral cleft lip and palate treated with allogeneic bone grafts were examined by a surgeon, orthodontist, and prosthodontist 20 to 47 months after surgery. Radiographic and clinical examination of the periodontal status of the teeth adjacent to the cleft and their antimeres were compared for differences with Student's t test and the Wilcoxon test. Radiographs indicated complete bone bridging in 21 patients. Two of the remaining three patients had a 1-mm radiolucent gap in the cleft site. The third patient had a 6-mm-wide radiolucency and recurrence of an oronasal fistula which was regrafted with autogenous bone. No statistically significant differences between the cleft and noncleft tooth antimeres were found for plaque, gingivitis, bleeding, sulcus depth, or level of attachment. A statistically significant difference in the amount of attached gingiva was found between the cleft and noncleft tooth antimeres. Nine patients with missing lateral incisor teeth avoided prosthetic replacement by orthodontic movement of the canine tooth into the grafted edentulous space. In those cases where the maxillary canine was unerupted at the time of the surgery, eruption into the graft occurred. Stability of the maxillary segments was sufficient to allow prosthodontic restoration with a fixed partial denture in those cases where it was indicated.

Adolescent↗
PubMed1990

Orthodontic considerations applied to craniofacial dysmorphology.

The contemporary management of patients with craniofacial anomalies involves a team approach of multiple specialists. Interaction between the basic scientist, developmental biologist, and the clinician should be an important aspect of interdisciplinary research if clinically relevant questions are to be addressed under rigorous laboratory conditions. The clinical investigator may be unfamiliar with the terminology and methodology of basic biomedical research. As a result, there can be a lack of communication between the clinician and the basic scientist. The role of the orthodontist in a multidisciplinary craniofacial team has evolved largely from an interest in dysmorphology as applied to craniofacial growth and development. The predictability of orthognathic surgery has been derived from the close collaboration between the orthodontist and surgeon and may be applied to the more comprehensive management of patients with craniofacial anomalies. To determine the mechanisms underlying the pathogenesis and response to treatment will require a collaborative approach by the clinician and research scientist to elucidate causal and putative risk factors in the complex genetic and environmental associations involved in craniofacial anomalies.

Causality↗
PubMed1989

Surgical correction of vertical maxillary excess during adolescence.

The timing of orthognathic surgery for the correction of dentofacial deformities is controversial. The expected predictable response to treatment in a young adult patient with vertical maxillary excess is illustrated by a case report. The concerns of the patient were addressed both morphologically and psychosocially. Postponing treatment for this group of patients until growth has finally stabilized may have far-reaching consequences, although the risk of outgrowing the correction is minimized. A retrospective study of 20 adolescents who had surgical impaction of the maxilla is reported.

Adolescent↗
PubMed1988

Minimal standards for reporting the results of surgery on patients with cleft lip, cleft palate, or both: a proposal.

This article proposes a set of minimal standards for reporting the results of surgery on patients with cleft lip with or without cleft palate and cleft palate only. These standards do not represent what is technically possible, only what is considered minimally acceptable for presentation in a public forum. They have a clinical focus and should be attainable by any well-constituted cleft palate team. As the title indicates, this document is a proposal. It is hoped that the readership will respond to the recommendations presented so that some set of standards can be adopted in the near future. Once adopted, these standards should be reviewed and updated periodically.

Cleft Lip↗
PubMed1986

Hybrid appliances: a component approach to dentofacial orthopedics.

The net treatment effect of or orthodontic or orthopedic therapy may be considered as the algebraic sum of all dentoalveolar, skeletal, and neuromuscular changes over time. Cumulative effects resulting from growth and adaptation in response to therapeutic biomechanical interference may be manipulated to result in clinically significant morphologic alterations in the growing child's dentition and craniofacial skeleton. All of the currently used functional appliances can be regarded as assemblies of a small number of component parts. This article attempts to identify these salient components and their respective contributions to the total design and probable function of such appliances. The logical consequence of such an analysis is the derivation of principles upon which the design of "hybrid" appliances may be based. Hybrid appliances are specifically and individually tailored to exploit the natural processes of growth and development. Such an approach represents a departure from the practice of adopting a "named" appliance for the treatment of a class of malocclusion. Instead, a detailed analysis of skeletodental and soft-tissue features, together with the patient's growth status and underlying cause of the malocclusion, are used to establish a set of treatment objectives. This in turn determines the selection of the components and their assemblies, resulting in appliance designs that uniquely match the needs of individual patients.

Activator Appliances↗
PubMed1986

Variables affecting measurements of vertical occlusal force.

Previous studies of occlusal force have provided conflicting results. The purpose of these studies was to determine whether the extent of vertical opening, contralateral occlusal support, or head posture influenced vertical occlusal forces during swallowing, simulated chewing, and maximum biting effort. Three samples of subjects with normal vertical facial proportions--one each of children, adolescents, and young adults--were evaluated to determine the effects of changes in small (2.5 vs. 6.0 mm) vertical separation of the first molars. A sample of young adults was used to evaluate changes in large (10-40 mm) vertical openings, and a sample of adolescents was used to investigate the effect of contralateral support and head posture. All between-group comparisons were evaluated using non-parametric statistics. For the small vertical openings, there was significantly more vertical occlusal force at 6.0 than 2.5 mm in children during swallowing and chewing but not during maximum biting effort. In adults, there was significantly more force during swallowing at 6.0 than at 2.5 mm separation, but no differences in chewing or maximum biting. Increasingly large vertical openings resulted in a progressive increase in maximum bite force to a maximum at about 20 mm, followed by a decrease and then a second increase to near-maximum force at about 40 mm for young adults. There were no significant differences in vertical force with or without contralateral support or between flexed, normal, and extended head postures at either of the small openings.

Adolescent↗
PubMed1985

Orthodontic-surgical interaction in the management of cleft lip and palate.

The orthodontist's role in the cleft palate team requires close collaboration with the surgeons and other team members. The rationale of timing and sequencing of orthodontic treatment have been discussed in the various time frames, which for convenience have been considered as follows: (1) neonatal or infant maxillary orthopedics; (2) orthodontic considerations in the primary dentition; (3) mixed dentition orthodontics to include presurgical recommendations before an alveolar bone graft and its rationale for use in selected patients; and (4) orthognathic surgery combining an orthodontic and surgical approach to the correction of dental and skeletal components of malocclusion in the permanent dentition. Speech considerations and the communicative skills of the patient with a cleft are important aspects in planning orthognathic surgery for this group of patients. Also, subsequent nose and lip revisions for cosmetic improvement must not be underestimated in the enhancement of the final result following correction of the skeletal and dental discrepancies. Provided the timing and sequencing of appropriate treatment modalities are planned in a closely coordinated, problem-oriented approach by the team members, cleft patients should currently have optimal functional and esthetic results.

Adolescent↗
PubMed1984

Craniofacial development: the possible mechanisms for some malformations.

Normal craniofacial development is reviewed and some mechanisms in the fusion of mammalian facial 'processes' are discussed. The manipulation of environmental factors and effects of teratogens are related to genetic susceptibility of animal models, and extrapolated to craniofacial malformations in man.

Abnormalities, Drug-Induced↗
PubMed1982

Reliability of soft tissue profile analysis in children.

Soft tissue outlines from profile radiographs, with or without supplementary photographs, do not provide enough information to reliably assess the underlying skeletal pattern in children 8 and 12 years old. Assessment was less reliable at 8 than at 12 years of age. Prognathic patterns were not as readily identified as retrognathic patterns. Specialty training did not affect the correctness of these limited assessments.

Cephalometry↗
PubMed1981

Primary failure of eruption: a possible cause of posterior open-bite.

Failure of posterior teeth to erupt fully into occlusal contact produces a lateral open-bite. These problems usually are attributed to a mechanical interference with the eruptive process, either ankylosis or some soft-tissue interference. In some patients, lateral open-bite is due to a disturbance of the eruption mechanism itself so that nonankylosed teeth cease to erupt. Influences on the eruption of teeth are reviewed, and possible causes of "primary failure of eruption" are discussed. The limitations of treatment for patients with eruption failure are described and illustrated by case reports.

Adolescent↗
PubMed1980

Early fracture of the mandibular condyles: frequently an unsuspected cause of growth disturbances.

Experience with patients referred to the Dentofacial Clinic at the University of North Carolina indicates that previous fracture of the mandibular condylar process may be involved in 5 to 10 percent of all severe mandibular deficiency or asymmetry problems. Since these fractures often go undiagnosed and since three fourths of the children with fractures have no growth deficits, the incidence of condylar fractures probably is much higher than commonly thought. Management of fracture patients immediately following the accident, during the postinjury stages of mandibular growth, and at completion or near-completion of growth is discussed.

Adolescent↗