Search PubMed⌕ Search

Biomedical subjects

J D Jacobs

Publications and source records attributed to J D Jacobs.

32 records · Page 2Linked to original sources
PubMed1981

Tridimensional planning for surgical/orthodontic treatment of mandibular excess.

The dentofacial deformity of mandibular excess is frequently complicated by significant discrepancies in the anteroposterior position of the maxilla and mandible. Disproportionality of facial height as a result of increased or decreased vertical growth of the jaws, labiomental contour, transverse arch relationships, and/or asymmetries also complicate this deformity. Planning treatment for mandibular prognathism must entail diagnostic consideration of all three dimensions of space if maximum results are to be obtained with contemporary surgical techniques. In this article some of these diagnostic considerations, pre- and postsurgical orthodontic objectives, surgical techniques, orthodontic sequencing, timing of treatment, and clinical results are delineated to acquaint the orthodontist with contemporary treatment planning for this deformity in order to obtain optimum function, esthetics, and relative stability. Tridimensional facial proportionality, occlusal balance, and good dental and skeletal stability were achieved in five patients (average age, 17.5 years) with relative or absolute mandibular prognathism. These patients, who were observed for an average postoperative follow-up period of 24 months, were treated by multiple maxillomandibular surgical procedures in concert with orthodontic treatment.

Adolescent↗
PubMed1980

Control of the transverse dimension with surgery and orthodontics.

Control of the transverse dimension through surgical techniques now available for use by the orthodontist is a valuable treatment consideration for orthodontic therapy in the nongrowing patient. In this article, proper diagnosis of relative and absolute transverse maxillary deficiency or excess is stressed as being imperative prior to completion of definitive orthodontic and/or surgical treatment planning. Therapeutic alternatives designed to facilitate correction of transverse discrepancies concomitant with treatment objectives in the sagittal and vertical dimensions are discussed and illustrated with case reports.

Adult↗
PubMed1980

Surgical-orthodontic correction of maxillary retrusion by Le Fort I osteotomy and proplast.

The combined efforts of the orthodontist and surgeon are necessary for successful treatment of most patients with maxillary retrusion. Both the aesthetic and functional manifestations of this dento-facial deformity can usually be effectively treated by maxillary advancement, augmentation of the midfacial region and orthodontics. Treatment planning, pre- and post-surgical orthodontic treatment principles, and surgical considerations in treating 25 adults with maxillary retrusion are described and illustrated. Surgical advancement of the maxilla by Le Fort I osteotomy, proper alignment of the teeth by orthodontics, and augmentation of the paranasal, canine fossae and malar regions with Proplast, were the common denominators of successful treatment.

Adolescent↗
PubMed1979

Combined orthodontic-surgical correction of moderate mandibular deficiency.

Carefully planned, coordinated, and executed orthodontic and surgical treatment is a viable alternative to traditional orthodontic treatment of patients with moderate mandibular deficiency. Recognition of their clinical manifestations is essential to distinguish between relative and absolute mandibular deficiency. If after clinical analysis of the Class II patient, esthetic priorities are established to maintain a balanced relationship between the upper lip and nose and not reduce the prominence of the upper lip, mandibular deficiency must be treated by surgical advancement of the mandible, superior repositioning of the maxilla, and consequent autorotational movement of the mandible forward and upward, or a combination of these procedures. The common denominator of successful therapy of absolute mandibular deficiency involves surgery to advance the mandible; relative mandibular deficiency, on the other hand, is treated by maxillary surgery to reposition the maxilla superiorly to allow forward and upward movement of the retropositioned mandible (autorotation). In actual clinical practice many patients manifest a combination of absolute and relative mandibular deficiency and are treated by maxillary and mandibular surgery. Lateral maxillary osteotomies, in concert with rapid maxillary expansion and genioplasty to alter the dimensions of the chin, are essential adjunctive surgical procedures to achieve three-dimensional esthetic and occlusal balance.

Adult↗
PubMed1979

Surgical-orthodontic correction of horizontal maxillary deficiency.

Selected maxillary osteotomies in concert with rapid maxillary expansion appliances are dependable adjuncts to treatment of the various clinical manifestations of horizontal maxillary deficiency and the accompanying crossbite. The important diagnostic, treatment planning, and technical considerations necessary for successful surgical-orthodontic correction of horizontal maxillary deficiency were discussed.

Adult↗
PubMed1977

Electrical stimulation of osteogenesis in periodontal defects.

Although the literature on bioelectrical phenomena is extensive, there is a paucity of research on its application in the field of dentistry. This study was designed to evaluate the effect of bioelectric phenomena on pathological osseous defects in the periodontium of Beagle dogs. Galvanic and thermocouple generators were designed to deliver a current in the nanoampere range. The galvanic unit implanted in the area of periodontal osseous defects in five dogs. These sites were randomly designated as experimental, active controls, and passive controls. The experimental and control units were implanted submucoperiosteally with the negative electrodes extending into the osseous defects. The bone was labeled with Procion Red H-8Bs at one week. Clinical and radiographic evaluation revealed no significant changes in the depth of the defects. The animals were sacrificed at 45 days and block sections were prepared. Histological measurement suggested that endosteal apposition was enhanced in all experimental sites as compared to controls. The results were discussed in relation to magnitude of current used, the influence of pathological bone, the potential of each type of experimental unit for clinical use, and the direction of further research in the area.

Animals↗
PubMed1976

Electrical stimulation of osteogenesis in pathological osseous defects.

Although the literature on bioelectric phenomena is extensive, there is a paucity of research on its application in the field of dentistry. This study was designed to evaluate the effect of bioelectrical stimulation on pathological osseous defects in the periodontium of Beagle dogs. Galvanic and thermocouple generators were designed to deliver a current in the nanoampere range. The galvanic unit produced a constant direct current. The thermocouple unit was designed to deliver an oscillating dc current. The generators were implanted in the area of periodontal osseous defects in five dogs. These sites were randomly designated as experimental, active controls, and passive controls. The experimental and control units were implanted submucoperiosteally with the negative electrodes extending into osseous defects. The bone was labeled with Procion Red H-8BS at 1 week. Clinical and radiographic evaluation revealed no significant changes in the depth of the defects. The animals were sacrificed at 45 days and block sections were prepared for histological measurement. From the results of this study it was concluded: 1. Induced constant or oscillating negative dc current levels in the nanoampere range were unsucessful in causing regeneration of periodontal osseous defects either clinically or radiographically in the Beagle dog over a 45-day period of application. 2. Constant or oscillating negative dc current levels in the nanoampere range did not stimulate a significant amount of periosteal osseous apposition. 3. Oscillating negative nanoampere dc currents produced an increase in endosteal osseous apposition as compared to controls. 4. Constant negative dc current in the nanoampere range produced an increase in endosteal osseous apposition as compared to controls. 5. The histological density of the bone in the area of pathological periodontal defects was increased in all experimental sites as compared to controls. 6. Devices of comparable size and construction to both the galvanic and thermocouple electronic units used in this study are acceptable for future investigation of the effect of bioelectrical stimulation on osteogenesis in alveolar bone.

Animals↗