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Accuracy of computerized cephalometric prediction tracings in extraction treatment
Reviews and abstracts
American Journal of Orthodontics and Dentofacial Orthopedics Volume 106, No. 1
t e e t h and soft tissue, or teeth, soft tissue, and bone. R e s t o r a t i o n s s u p p o r t e d solely by implants invariably require a g r e a t e r n u m b e r of implants t h a n the simpler less sophisticated implant a n d soft tissue s u p p o r t e d structures. T h e b o o k is intended primarily for implant surgeons. B e c a u s e of this m a n y c h a p t e r s or portions of c h a p t e r s will b e of little or no interest to orthodontists. However, in the interests of their patients and/or in an effort to u p d a t e or acquire a k n o w l e d g e of implantology, orthodontists would do well to own, or at least have r e a d y access to, such an atlas. T h e m a n y p h o t o g r a p h s almost all o f which are beautifully r e p r o d u c e d on quality high-gloss p a p e r clearly illustrate the variety of implant prostheses now available to patients. Alex Jacobson
Thesis abstracts Calcium flux and cell volume changes in anisosmotically treated fibroblasts. K.J. Bibby* and C. A. G. McCulloch. Toronto, Canada: University of Toronto, 1993
Alteration of the cell volume of attached fibroblasts with anisosmotic buffers was used as a model system to examine the relationship between cell membrane perturbation and intracellular calcium concentration, and to study pathways that may be involved in transducing this response. Human periodontal ligament fibroblasts and human gingival fibroblasts grown on glass coverslips for 24 hours were loaded with fura-2-AM. The relative cell volume change of single fibroblasts was estimated by measurement of fluorescence intensity at the isosbestic wavelength (356 nm), whereas [Ca2~]i was calculated from ratiometric fura-2 emission with excitation at 345 nm and 380 nm. Isotonic buffer (300 mOsmM) was substituted with either hypertonic (600 mOsM) or hypotonic (150 mOsM) buffer after baseline recordings. Attached periodontal and gingival fibroblasts exhibited a rapid decrease in cell volume (p < 0.05) and intracellu'lar calcium following hypertonic buffer treatment, Which ~was associated with an increase in filamentous (F) actin staining (p < 0.001). In contrast, fibroblasts treated with hypotonic buffers demonstrated an increase in cell volume (mean - 1 0 % ; p < 0.05), a significant decrease in F-actin staining (p < 0.001), and a rapi d, transient elevation in [Ca2~]i (mean - 2 8 0 n M ; p < 0.05). This [Ca2+]i rise was significantly inhibited by EGTA, and gadolinium ions (p < 0.05 ), indicating an influx of Ca 2. through istretch activated ion channels. Pretreatment with a specific tyrosine kinase inhibitor genistein, or the Gs subunit 9activator cholera toxin significantly inhibited the hypoosmolar [Ca2*]i response, as did incomplete cell spreading
111
(p < 0.05). Inhibitors of F-actin diminished the [CaZ§ peak. These results indicate that [Ca2*]i fluxes in response to hypotonic cell swelling in attached fibroblasts are mediated by stretch activated ion channels. Calcium entry in response to membrane strain may be modulated by tyrosine kinases and G-proteins, and is affected by cell shape. Supported by MRC Canada # MA-8903. Possible etiologic factors in root resorption during orthodontic treatment: A literature review. D.S. Huang. New York, N. Y.: Cohonbia UniversiO, School of Dental and Oral Surger); DMsion o f Orthodontics, 1993
The purpose of this literature review is to evaluate the etiologic factors and predictability of root resorption, which is one of the most common risks associated with orthodontic treatment. 120 articles were reviewed and more than 20 factors were discussed. The findings were that of those factors discussed the ones that had possible influence on the root resorption during orthodontic treatment were (1) individual susceptibility such as hormone, body type and metabolic rate, (2) systemic factors such as endocrine disorders and systemic disease, (3) genetic factor, (4) age factor such as older age was more at risk, (5) degree of root formation factor such as incomplete formed root was less at risk, (6) tooth structure factor such as deviating root form like pipette shaped was more susceptible, (7) habits factor such as nail-biting, finger sucking and tongue thrusting, which caused the roots more at risk, (8) the presence of root resorption before orthodontic treatment factor which rendered the root more susceptible, (9) previously traumatized teeth factor which made the teeth more liable to resorption, (10) specific tooth vulnerability such as anterior teeth and maxillary teeth were more at risk, (11) orthodontic movement type factor such as tipping, torquing, and intrusion, which made the roots more susceptible, (12) orthodontic force factor such as stronger and continuous force would make root more susceptible, (13) treatment duration factor such as longer the active treatment, the greater the chance of resorption. Other factors which either had no influence on root resorption or had i:ontroversial reports on root resorption were nutrition, gender endodontically treated teeth, alveolar bone density, malocclusion, and the type of appliance used. Accuracy of computerized cephalometric 9 prediction tracings in extraction treatment, N. J. Capolongo. New York, N. Y..: Colambia University 1993
In the past decade, there have been extensive advances in computer technology that have allowed the orthodontist to expand their usage in diagnosis and presentation. The purpose of this study was to assess the accuracy of
112
Reviews and abstracts
one commercial diagnostic computer program (Quick Ceph). Fourteen nongrowing patients who completed full-banded orthodontic treatment with extractions of their first four premolars were identified. Computer generated prediction tracings were executed for each patient by three independent orthodontists. They were compared with actual posttreatment cephalograms. Results showed a large range of variability bz predicted vahres between tire orthodontists and each individual orthodontist versus the actual vahre, although the predicted values were all within 2 SDs of the actual value. Superimpositions revealed a consistent overretraction of U1 and L1 and excess labial crown torque in the predicted value. Use of a computer generated prediction trachrg by a practitioner does offer a reasonable look at posttreatment results but does trot define the final results in detail
Delayed eruption and ankylosis: A literature review. T. G. Rice. New York, N. Y.: Coh~mbia University School of Dental and Oral Surge~ 1993 This paper reviews the literature concerning the problems of delayed eruption and ankylosis. The clinical conditions, epidemiologic data, case studies, and popular beliefs concerning noneruptive teeth are reviewed. A review of the literature concerning the cause of normal dental eruption is made. Clinical management of noneruptive teeth is discussed in light of the scientific and clinical information available to the orthodontist. Proper management of patients exhibiting delayed entption and ankylosis requires serial clinical and radiographic evaluation and a comprehensive understanding of the eruption process.
Study of facial proportions of a native Puerto Rican group. E.C. Galarza*. New York, N. Y.: Cohtmbia Universi~ 1993 The purpose of this study was to compare facial proportions of an esthetically pleasing native Puerto Rican group with the norms given for a random group of Puerto Rican and white subjects, as well as esthetically pleasing white subjects. Data was obtained from the right side profile and frontal photographs of 16 subjects (10 females, 6 males) who were chosen as being esthetically pleasing by nonorthodontists. The analysis was done using the profilometric analysis given by Peck and Peck and the frontal and profile proportional indices given by Farkas et al. A Student's t test was used to evaluate the significance of the measurements. Among the most significant findings within the esthetically pleasing group of Puerto Ricans were: a less prognathic mandible, higher nasomaxiUary angle, smaller nose, higher maxillary height and lower mandibular height than esthetically pleasing white subjects. As expected, most of the facial proportions of the esthetically pleasing Puerto Rican group were significantly different from the random white and Puerto Rican groups.
American Journal of Orthodontics and Dentofacial Orthopedics July 1994
Functional appliances: A literature review. k. Singgih. New York, New York_"Cohlmbia University School of Dental and Oral Suvge~ Division of Orthodontics, 1993 The purpose of this literature review was to evaluate the effect of hyperpropulsor on animals, as well as the effects of activator and Frankel's functional regulator on the dentofacial structures in the treatment of Class II, Division 1 malocclusion. Thirty literatures from 1951 to 1990 had been reviewed. Tire age or developmental stage of tire anbnal was cntcial in determinbrg tlre adaptability potential of the temporomandibularjohrt: in the young and growing animals the growth response after hyperpropulsor appliance was great and fast, whereas in matured animals it induced traumatization of the fibrocartilage and severe traumatic resorption of the articular eminence. The clinical studies from the activator treatment resulted in tlre reduction of tire overjet and the hnprovement of the molar relatioluhip. However, its orthopedic effect was controversial Functional regulator elicited similar controversy. There was no significant difference bem'een activator and fimctional regulator clinically, except that the latter claimed to be able to correct mentalis strain and accomplished better transverse correction. Functional appliance can modify mandibular growth when used proper~ providing that tlre patient has good compliance and favorable growth.
Inflammatory mediators in stressed temporomandibular joint synovial fluid of rabbits. E-S Kim. New York, New York." CohLmbia Universiff, School of Dental and Oral Surgeq, 1993 It is generally believed that growth of the mandibular condyle is compensatory and adaptive in nature. However, the mechanism(s) of this response is/are still unclear. The purpose of this study was to investigate whether a neurotransmitter, such as substance P (SP) and a cytokine such as interleukin-ll3 (IL-113), can be detected in the synovial fluid (SF) of the. TMJ after induced mandibular dysfunction, whether their relative concentration varies with the duration of stimulus and with the growth status of the animals. Twenty-four New Zealand rabbits, 42-day-old or 200-day-old were randomly divided into two groups. The experimental animals had an occlusal splint bonded on the left mandibular molars only. After 3 or 14 days of experiment, SF of each joint was aspirated and the joint was examined through an arthroscope. Both joints were dissected and processed for histology. The IL-113 level was measured by enzyme linked immunosorbent assay (ELISA) and the SP level with a radioimmunoassay. Arthroscopic evaluation revealed significant signs of synovitis only in the joints of older experimental animals compared with the controls. The IL-113 levels increased significantly in both age groups after 3 days and to a lesser degree after 14 days. On the other hand, SP was not found in SF aspirates of either control or experimental animals. Examination of
American Journal of Orthodontics and Dentofacial Orthopedics Volume 106, No. 1
t e e t h and soft tissue, or teeth, soft tissue, and bone. R e s t o r a t i o n s s u p p o r t e d solely by implants invariably require a g r e a t e r n u m b e r of implants t h a n the simpler less sophisticated implant a n d soft tissue s u p p o r t e d structures. T h e b o o k is intended primarily for implant surgeons. B e c a u s e of this m a n y c h a p t e r s or portions of c h a p t e r s will b e of little or no interest to orthodontists. However, in the interests of their patients and/or in an effort to u p d a t e or acquire a k n o w l e d g e of implantology, orthodontists would do well to own, or at least have r e a d y access to, such an atlas. T h e m a n y p h o t o g r a p h s almost all o f which are beautifully r e p r o d u c e d on quality high-gloss p a p e r clearly illustrate the variety of implant prostheses now available to patients. Alex Jacobson
Thesis abstracts Calcium flux and cell volume changes in anisosmotically treated fibroblasts. K.J. Bibby* and C. A. G. McCulloch. Toronto, Canada: University of Toronto, 1993
Alteration of the cell volume of attached fibroblasts with anisosmotic buffers was used as a model system to examine the relationship between cell membrane perturbation and intracellular calcium concentration, and to study pathways that may be involved in transducing this response. Human periodontal ligament fibroblasts and human gingival fibroblasts grown on glass coverslips for 24 hours were loaded with fura-2-AM. The relative cell volume change of single fibroblasts was estimated by measurement of fluorescence intensity at the isosbestic wavelength (356 nm), whereas [Ca2~]i was calculated from ratiometric fura-2 emission with excitation at 345 nm and 380 nm. Isotonic buffer (300 mOsmM) was substituted with either hypertonic (600 mOsM) or hypotonic (150 mOsM) buffer after baseline recordings. Attached periodontal and gingival fibroblasts exhibited a rapid decrease in cell volume (p < 0.05) and intracellu'lar calcium following hypertonic buffer treatment, Which ~was associated with an increase in filamentous (F) actin staining (p < 0.001). In contrast, fibroblasts treated with hypotonic buffers demonstrated an increase in cell volume (mean - 1 0 % ; p < 0.05), a significant decrease in F-actin staining (p < 0.001), and a rapi d, transient elevation in [Ca2~]i (mean - 2 8 0 n M ; p < 0.05). This [Ca2+]i rise was significantly inhibited by EGTA, and gadolinium ions (p < 0.05 ), indicating an influx of Ca 2. through istretch activated ion channels. Pretreatment with a specific tyrosine kinase inhibitor genistein, or the Gs subunit 9activator cholera toxin significantly inhibited the hypoosmolar [Ca2*]i response, as did incomplete cell spreading
111
(p < 0.05). Inhibitors of F-actin diminished the [CaZ§ peak. These results indicate that [Ca2*]i fluxes in response to hypotonic cell swelling in attached fibroblasts are mediated by stretch activated ion channels. Calcium entry in response to membrane strain may be modulated by tyrosine kinases and G-proteins, and is affected by cell shape. Supported by MRC Canada # MA-8903. Possible etiologic factors in root resorption during orthodontic treatment: A literature review. D.S. Huang. New York, N. Y.: Cohonbia UniversiO, School of Dental and Oral Surger); DMsion o f Orthodontics, 1993
The purpose of this literature review is to evaluate the etiologic factors and predictability of root resorption, which is one of the most common risks associated with orthodontic treatment. 120 articles were reviewed and more than 20 factors were discussed. The findings were that of those factors discussed the ones that had possible influence on the root resorption during orthodontic treatment were (1) individual susceptibility such as hormone, body type and metabolic rate, (2) systemic factors such as endocrine disorders and systemic disease, (3) genetic factor, (4) age factor such as older age was more at risk, (5) degree of root formation factor such as incomplete formed root was less at risk, (6) tooth structure factor such as deviating root form like pipette shaped was more susceptible, (7) habits factor such as nail-biting, finger sucking and tongue thrusting, which caused the roots more at risk, (8) the presence of root resorption before orthodontic treatment factor which rendered the root more susceptible, (9) previously traumatized teeth factor which made the teeth more liable to resorption, (10) specific tooth vulnerability such as anterior teeth and maxillary teeth were more at risk, (11) orthodontic movement type factor such as tipping, torquing, and intrusion, which made the roots more susceptible, (12) orthodontic force factor such as stronger and continuous force would make root more susceptible, (13) treatment duration factor such as longer the active treatment, the greater the chance of resorption. Other factors which either had no influence on root resorption or had i:ontroversial reports on root resorption were nutrition, gender endodontically treated teeth, alveolar bone density, malocclusion, and the type of appliance used. Accuracy of computerized cephalometric 9 prediction tracings in extraction treatment, N. J. Capolongo. New York, N. Y..: Colambia University 1993
In the past decade, there have been extensive advances in computer technology that have allowed the orthodontist to expand their usage in diagnosis and presentation. The purpose of this study was to assess the accuracy of
112
Reviews and abstracts
one commercial diagnostic computer program (Quick Ceph). Fourteen nongrowing patients who completed full-banded orthodontic treatment with extractions of their first four premolars were identified. Computer generated prediction tracings were executed for each patient by three independent orthodontists. They were compared with actual posttreatment cephalograms. Results showed a large range of variability bz predicted vahres between tire orthodontists and each individual orthodontist versus the actual vahre, although the predicted values were all within 2 SDs of the actual value. Superimpositions revealed a consistent overretraction of U1 and L1 and excess labial crown torque in the predicted value. Use of a computer generated prediction trachrg by a practitioner does offer a reasonable look at posttreatment results but does trot define the final results in detail
Delayed eruption and ankylosis: A literature review. T. G. Rice. New York, N. Y.: Coh~mbia University School of Dental and Oral Surge~ 1993 This paper reviews the literature concerning the problems of delayed eruption and ankylosis. The clinical conditions, epidemiologic data, case studies, and popular beliefs concerning noneruptive teeth are reviewed. A review of the literature concerning the cause of normal dental eruption is made. Clinical management of noneruptive teeth is discussed in light of the scientific and clinical information available to the orthodontist. Proper management of patients exhibiting delayed entption and ankylosis requires serial clinical and radiographic evaluation and a comprehensive understanding of the eruption process.
Study of facial proportions of a native Puerto Rican group. E.C. Galarza*. New York, N. Y.: Cohtmbia Universi~ 1993 The purpose of this study was to compare facial proportions of an esthetically pleasing native Puerto Rican group with the norms given for a random group of Puerto Rican and white subjects, as well as esthetically pleasing white subjects. Data was obtained from the right side profile and frontal photographs of 16 subjects (10 females, 6 males) who were chosen as being esthetically pleasing by nonorthodontists. The analysis was done using the profilometric analysis given by Peck and Peck and the frontal and profile proportional indices given by Farkas et al. A Student's t test was used to evaluate the significance of the measurements. Among the most significant findings within the esthetically pleasing group of Puerto Ricans were: a less prognathic mandible, higher nasomaxiUary angle, smaller nose, higher maxillary height and lower mandibular height than esthetically pleasing white subjects. As expected, most of the facial proportions of the esthetically pleasing Puerto Rican group were significantly different from the random white and Puerto Rican groups.
American Journal of Orthodontics and Dentofacial Orthopedics July 1994
Functional appliances: A literature review. k. Singgih. New York, New York_"Cohlmbia University School of Dental and Oral Suvge~ Division of Orthodontics, 1993 The purpose of this literature review was to evaluate the effect of hyperpropulsor on animals, as well as the effects of activator and Frankel's functional regulator on the dentofacial structures in the treatment of Class II, Division 1 malocclusion. Thirty literatures from 1951 to 1990 had been reviewed. Tire age or developmental stage of tire anbnal was cntcial in determinbrg tlre adaptability potential of the temporomandibularjohrt: in the young and growing animals the growth response after hyperpropulsor appliance was great and fast, whereas in matured animals it induced traumatization of the fibrocartilage and severe traumatic resorption of the articular eminence. The clinical studies from the activator treatment resulted in tlre reduction of tire overjet and the hnprovement of the molar relatioluhip. However, its orthopedic effect was controversial Functional regulator elicited similar controversy. There was no significant difference bem'een activator and fimctional regulator clinically, except that the latter claimed to be able to correct mentalis strain and accomplished better transverse correction. Functional appliance can modify mandibular growth when used proper~ providing that tlre patient has good compliance and favorable growth.
Inflammatory mediators in stressed temporomandibular joint synovial fluid of rabbits. E-S Kim. New York, New York." CohLmbia Universiff, School of Dental and Oral Surgeq, 1993 It is generally believed that growth of the mandibular condyle is compensatory and adaptive in nature. However, the mechanism(s) of this response is/are still unclear. The purpose of this study was to investigate whether a neurotransmitter, such as substance P (SP) and a cytokine such as interleukin-ll3 (IL-113), can be detected in the synovial fluid (SF) of the. TMJ after induced mandibular dysfunction, whether their relative concentration varies with the duration of stimulus and with the growth status of the animals. Twenty-four New Zealand rabbits, 42-day-old or 200-day-old were randomly divided into two groups. The experimental animals had an occlusal splint bonded on the left mandibular molars only. After 3 or 14 days of experiment, SF of each joint was aspirated and the joint was examined through an arthroscope. Both joints were dissected and processed for histology. The IL-113 level was measured by enzyme linked immunosorbent assay (ELISA) and the SP level with a radioimmunoassay. Arthroscopic evaluation revealed significant signs of synovitis only in the joints of older experimental animals compared with the controls. The IL-113 levels increased significantly in both age groups after 3 days and to a lesser degree after 14 days. On the other hand, SP was not found in SF aspirates of either control or experimental animals. Examination of