Biomedical subjects

Paul W Major

Publications and source records attributed to Paul W Major.

At least 19 recordsLinked to original sources

PubMed2006

A systematic review of cephalometric facial soft tissue changes with the Activator and Bionator appliances in Class II division 1 subjects.

The objective of the present systematic review was to evaluate, through lateral cephalograms, facial soft tissue changes after the use of the Activator and Bionator appliances in Class II division 1 malocclusion subjects. Several electronic databases (PubMed, Medline, Medline In-Process and Other Non-Indexed Citations, Cochrane Database, Embase, Web of Sciences, and Lilacs) were searched with the assistance of a senior health sciences librarian. Abstracts, which appeared to fulfil the initial criteria, were selected by consensus. The original articles were then retrieved. Their references were also hand searched for possible missing articles. Clinical trials, which assessed facial soft tissue changes with the use of either an Activator or a Bionator appliance without any surgical intervention or syndromic characteristics, were considered. A comparable untreated control group was required to factor out normal growth changes. Five articles using the Activator and six using the Bionator fulfilled the selection criteria and quantified facial soft tissue changes. An individual analysis of these articles was undertaken and some methodological flaws were identified. Based on the available evidence, a significant amount of controversy regarding the soft tissue changes produced by the Activator and the Bionator exists. Soft tissue changes that were reported as being statistically significant were of questionable clinical significance. Long-term, double-blinded, prospective randomized clinical trials are needed to confirm the findings. Three-dimensional quantification is also required to overcome current limitations in our understanding of the soft tissue changes obtained with the use of removable functional appliances.

Activator Appliances↗

PubMed2006

Analgesic action of gabapentin on chronic pain in the masticatory muscles: a randomized controlled trial.

Chronic masticatory myalgia (CMM) can be defined as constant pain in the masticatory muscles for more than 6 months and is influenced by the central nervous system. The antiepileptic agent gabapentin acts centrally and is used for managing different types of chronic pain conditions. The objective of this study was to evaluate the analgesic action of gabapentin on CMM. In this 12-week randomized controlled clinical trial 50 patients were randomly allocated into two study groups: 25 received gabapentin and 25 received placebo. The outcome measures utilized were pain reported on a VAS (VAS-pain), Palpation Index (PI) and impact of CMM on daily functioning reported on a VAS (VAS-function). Thirty-six patients completed the study. Gabapentin showed to be clinically and statistically superior to placebo in reducing pain reported by patients (gabapentin=51.04%; placebo=24.30%; P=0.037), masticatory muscle hyperalgesia (gabapentin=67.03%; placebo=14.37%; P=0.001) and impact of CMM on daily functioning (gabapentin=57.70%; placebo=16.92%; P=0.022). It can be concluded from this study that gabapentin is effective for the management of CMM.

Adolescent↗

PubMed2006

Validity, reliability, and reproducibility of plaster vs digital study models: comparison of peer assessment rating and Bolton analysis and their constituent measurements.

INTRODUCTION: The objective of this validation study was to compare standard plaster models (the current gold standard for cast measurements) with their digital counterparts made with emodel software (version 6.0, GeoDigm, Chanhassen, Minn) for the analysis of tooth sizes and occlusal relationships--specifically the Bolton analysis and the peer assessment rating (PAR) index and their components. METHODS: Dental casts were poured from 24 subjects with 8 malocclusion types grouped according to American Board of Orthodontics categories. Measurements were made with a digital caliper to the nearest 0.01 mm from plaster models and with the software from the digital models. A paired samples t test was used to compare reliability and validity of measurements between plaster and digital methods. RESULTS: Reproducibility of digital models via the concordance correlation coefficient was excellent in most cases and good in some. Although statistically significant differences in some measurements were found for the reliability and validity of the digital models via the average mean of the absolute differences of repeated measurements, none was clinically significant. Grouping of the measurements according to the 8 American Board of Orthodontics categories produced no significant difference (Kruskal-Wallis test). No measurement associated with Bolton analysis or PAR index made on plaster vs digital models showed a clinically significant difference. The PAR analysis and its constituent measurements were not significantly different clinically between plaster and emodel media. CONCLUSIONS: Preliminary results did not indicate that digital models would cause an orthodontist to make a different diagnosis of malocclusion compared with plaster models; digital models are not a compromised choice for treatment planning or diagnosis.

Computer Simulation↗

PubMed2006

Longitudinal study of temporomandibular joint disc status and craniofacial growth.

INTRODUCTION: The objective of this retrospective cohort study was to assess the association of temporomandibular joint (TMJ) disc status and craniofacial growth. METHODS: Seventy-nine subjects (52 female, 27 male) with and without TMJ disc abnormalities were followed for a mean time of 3 years 8 months. Of this sample, 40 subjects (21 female, 19 male) received orthodontic treatment. Disc displacement and disc length measurements from magnetic resonance imaging of the jaw joints were used to evaluate TMJ disc status. A principal component analysis was used to produce a single disc status score per subject. Horizontal and vertical growth changes were obtained from cephalometric radiographs. The Fishman skeletal maturation index system was used to obtain the percentage of the total craniofacial growth attained. In addition, previous orthodontic treatment and time frames between the follow-up cephalometric radiographs were considered. RESULTS: A stepwise multiple linear regression analysis was used to evaluate the influence of TMJ disc status and orthodontic treatment on the displacement vectors between initial records (T1) and final records (T2) for each cephalometric point. Less horizontal and vertical growth was found in specific regions of the maxilla and the mandible in subjects with TMJ disc abnormalities, although their respective determination coefficients were mild (R2 <11.2%). CONCLUSIONS: TMJ disc abnormality was associated with reduced forward growth of the maxillary and mandibular bodies. TMJ disc abnormality was associated with reduced downward growth of the mandibular ramus.

Cephalometry↗

PubMed2006

Variations in orthodontic treatment planning decisions of Class II patients between virtual 3-dimensional models and traditional plaster study models.

INTRODUCTION: Study models provide invaluable information in treatment planning. Digital models have proved to be an effective measurement tool, but their use in treatment planning has not been studied. METHODS: Ten sets of records of Class II malocclusion subjects (dental study models, lateral cephalograms/tracings, panoramic radiographs, intraoral and extraoral photographs) were used for treatment planning by 20 orthodontists on 2 separate occasions. Digital models were used to evaluate the patients at 1 session and plaster models were used at the other session. Treatment recommendations were scored and compared for agreement. Eleven orthodontists served as the control group, looking at the records on 2 occasions with plaster models for agreement. RESULTS: Good agreement was noted for surgery (P = 1.00, kappa = 0.549), extractions (P = .360, kappa = 0.570), and auxiliary appliances (P = 1.00, kappa = 0.539) for the digital/plaster group. Agreement in the plaster/plaster group for surgery (P = 1.00, kappa = 0.671), extractions (P = 1.00, kappa = 0.626), and auxiliary appliances (P = .791, kappa = 0.672) was also good. Overall proportions of agreement ranged between 0.777 and 0.870 for digital/plaster and 0.818 and 0.873 for plaster/plaster. CONCLUSIONS: There was no statistical difference in intrarater treatment-planning agreement for Class II malocclusions based on the use of digital models in place of traditional plaster models. Digital orthodontic study models (e-models) are a valid alternative to traditional plaster study models in treatment planning for Class II malocclusion patients.

Computer Simulation↗

PubMed2006

True molar intrusion attained during orthodontic treatment: a systematic review.

INTRODUCTION: The aim of this systematic review was to quantify the amount of true molar intrusion attainable during orthodontic treatment. METHODS: A literature search was conducted to identify clinical trials that assessed true molar intrusion through superimposition of lateral cephalogram tracings. Craniofacial growth had to be factored out when appropriate. Electronic databases (Pubmed, Medline, Medline In-Process & Other Non-Indexed Citations, all EBM reviews, Embase, Web of Science, and Lilacs) were searched with the help of a senior health-sciences librarian. Abstracts that appeared to fulfill the initial selection criteria were selected, and the full-text original articles were then retrieved and analyzed. Only articles that fulfilled the final selection criteria were finally considered. Their references were also hand-searched for possible missing articles from the database searches. RESULTS: Thirty abstracts met the initial inclusion criteria, and these articles were retrieved. From these, 29 were later rejected because they did not either quantify true molar intrusion or factor out normal craniofacial growth when required. Only 1 article remained, and it showed a mean maxillary molar intrusion of 0.96 mm (SD, 0.54) in 12 subjects. CONCLUSIONS: True molar intrusion appears to be achievable in the maxillary arch, although the amount of evidence is minimal. The clinical significance of the magnitude of the true intrusion reported is questionable as the sole treatment option to correct open-bite malocclusions. Better quantification method of the true intrusion attained has to be utilized.

Clinical Trials as Topic↗

PubMed2006

Assessment of lateral cephalometric diagnosis of adenoid hypertrophy and posterior upper airway obstruction: a systematic review.

INTRODUCTION: Our objective was to evaluate the capability of lateral cephalograms in diagnosing hypertrophied adenoids and obstructed posterior nasopharyngeal airways. METHODS: A systematic review of the literature by using several electronic databases (Cochrane Library, Medline, Medline in progress, PubMed, Web of Science, Embase, and Lilacs) was performed with the help of a senior health-sciences librarian. The electronic search was followed up with hand searches. After applying our inclusion-exclusion criteria, the search yielded 11 articles that were then scored based on their methodological validity. RESULTS: Lateral cephalograms performed reasonably well in evaluating adenoid size; both quantitative measures of adenoid area and subjective grading of adenoid size on lateral cephalograms had reasonable correlations to actual adenoid size (range of r, 0.60 to 0.88). However, evidence suggested that cephalograms were less ideal for evaluating the size of the posterior nasopharyngeal airway. The diagnostic difference is likely because the adenoid is a simpler 3-dimensional structure than the nasopharynx; therefore, it loses less information when compressed into 2 dimensions by the radiograph. CONCLUSIONS: Being used as a screening tool to determine the need for more rigorous ENT follow-up appears to be the greatest utility of lateral cephalograms. Because no consensus could be reached on what are the most useful landmarks, we recommend that clinicians look for multiple deviant measures of adenoid size rather than one definitive quantification.

Adenoids↗

PubMed2006

Plane orientation for standardization in 3-dimensional cephalometric analysis with computerized tomography imaging.

INTRODUCTION: The purpose of this study was to propose certain landmarks and planes to standardize 3-dimensional image orientation. METHODS: Cone-beam computerized tomographic images were obtained from 10 adolescent patients and analyzed with AMIRA software (AMIRA, Mercury Computer Systems, Berlin, Germany). RESULTS: Four points (ELSA, right superior external auditory meatus, left superior external auditory meatus, and mid-dorsum foramen magnum) were located on each image. The axial-horizontal plane (x-y plane) was then determined by using both superior external auditory meatus and ELSA; the sagittal-vertical plane (z-y plane) was formed by ELSA and mid-dorsum foramen magnum perpendicular to the x-y plane. CONCLUSIONS: All points had high intrareliability and were adequate for standardizing the orientation of 3-dimensional images.

Adolescent↗

PubMed2006

Search and selection methodology of systematic reviews in orthodontics (2000-2004).

INTRODUCTION: More systematic reviews related to orthodontic topics are published each year, although little has been done to evaluate their search and selection methodologies. METHODS: Systematic reviews related to orthodontics published between January 1, 2000, and December 31, 2004, were searched for their use of multiple electronic databases and secondary searches. The search and selection methods of identified systematic reviews were evaluated against the Cochrane Handbook's guidelines. RESULTS: Sixteen orthodontic systematic reviews were identified in this period. The percentage of reviews documenting and using each criterion of article searching has changed over the last 5 years, with no recognizable directional trend. On average, most systematic reviews documented their electronic search terms (88%) and inclusion-exclusion criteria (100%), and used secondary searching (75%). Many still failed to search more than MEDLINE (56%), failed to document the database names and search dates (37%), failed to document the search strategy (62%), did not use several reviewers for selecting studies (75%), and did not include all languages (81%). CONCLUSIONS: The methodology of systematic reviews in orthodontics is still limited, with key methodological components frequently absent or not appropriately described.

Databases, Bibliographic↗

PubMed2006

Correlation of skeletal maturation stages determined by cervical vertebrae and hand-wrist evaluations.

The aim of this study was to assess the correlation between the Fishman maturation prediction method (FMP) and the cervical vertebral maturation (CVM) method for skeletal maturation stage determination. Hand-wrist and lateral cephalograms from 79 subjects (52 females and 27 males) were used. Hand-wrist radiographs were analyzed using the FMP to determine skeletal maturation level (advanced, average, or delayed) and stage (relative position of the individual in the pubertal growth curve). Cervical vertebrae (C2, C3, and C4) outlines obtained from lateral cephalograms were analyzed using the CVM to determine skeletal maturation stage. Intraexaminer reliability (Intraclass correlation coefficient [ICC]) for both methods was calculated from 10 triplicate hand-wrist and lateral cephalograms from the same patients. An ICC coefficient of 0.985 for FMP and an ICC of 0.889 for CVM were obtained. A Spearman correlation value of 0.72 (P < .001) was found between the skeletal maturation stages of both methods. When the sample was subgrouped according to skeletal maturation level, the following correlation values were found: for early mature adolescents 0.73, for average mature adolescents 0.70, and for late mature adolescents 0.87. All these correlation values were statistically different from zero (P < .024). Correlation values between both skeletal maturation methods were moderately high. This may be high enough to use either of the methods indistinctively for research purposes but not for the assessment of individual patients. Skeletal level influences the correlation values and, therefore, it should be considered whenever possible.

Adolescent↗

PubMed2006

Canadian orthodontist Internet user profile.

An anonymous, self-administered, mail-out survey of Canadian Orthodontists was conducted to evaluate the characteristics of orthodontic Internet use. The response rate was 45.6% (304 of 667). A total of 76.6% of orthodontists reported having Internet access at work, and an additional 12.4% reported having Internet access from a different location. Statistically significant associations between Internet usage and office staff size (P < .001) and years of practice (P = .046) were observed. Offices with larger staffs had greater Internet access. Number of staffs and number of case starts were positively correlated (P < .001, r = 0.498). The odds ratio for having Internet access on the basis of increased case starts from the less than 100 to 300-399 categories was 5.67. Although not statistically significant, there was a trend for greater Internet access by younger practitioners.

Adult↗

PubMed2006

Soft tissue changes with fixed functional appliances in Class II division 1.

OBJECTIVE: To evaluate facial soft tissue changes after the use of fixed functional appliances in Class II division 1 malocclusion cases using a systematic review of the literature. MATERIALS AND METHODS: Several electronic databases (PubMed, Medline, Medline In-Process & Other Non-Indexed Citations, Cochrane Database, Embase, Web of Sciences, and Lilacs) were searched with the help of a senior Health Sciences librarian. Abstracts that appeared to fulfill the initial selection criteria were selected by consensus. The original articles were then retrieved. Their references were also hand-searched for possible missing articles. Clinical trials assessing facial soft tissue changes with the use of fixed functional appliances without any surgical intervention or syndromic characteristics were considered. A comparable untreated control group was required to factor out normal growth changes. Four articles using Herbst and one using Jasper Jumper fulfilled the selection criteria. An individual analysis of these articles was made and some methodological flaws were identified. RESULTS: Although fixed functional appliances produce some significant statistical changes in the soft tissue profile, the magnitude of the changes may not be perceived as clinically significant. CONCLUSIONS: The conclusions from this systematic review should be considered with caution because only a secondary level of evidence was found. Long-term double-blinded prospective randomized clinical trials are needed. Three-dimensional quantification of the soft tissue changes is required to overcome current limitations in our understanding of the soft tissue changes obtained with the use of fixed functional appliances.

Activator Appliances↗

PubMed2006

Predictive factors of vertical bone depth in the paramedian palate of adolescents.

OBJECTIVE: To determine whether a relationship exists between the vertical bone depth in the paramedian palate (PP) of growing patients and age, gender, and palatal morphology. Clinically detectable traits may decrease the need for further imaging prior to implant placement for orthodontic anchorage. MATERIALS AND METHODS: Cone beam computed tomagraphic scans (Newtom-9000, Verona, Italy) were acquired in 183 orthodontic patients (10-19 years old). Vertical bone depth was measured at nine unilateral locations in the PP of each subject. Measurements were analyzed with univariate and multivariate statistical tests. RESULTS: Significant variability in the bone thickness was found among locations and among subjects. Male subjects had significantly greater mean bone thickness in six of the nine locations measured, showing a mean of 1.22 mm more vertical bone than females showed at these locations. Age and palatal measurements did not demonstrate a clinically useful relationship with bone depth. CONCLUSIONS: Age and palatal morphology are not valid predictors of bone height in the PP. Because of the large variability of bone thickness in this region, computed tomographic imaging remains valuable prior to paramedian implant placement in growing individuals. The paramedian palate presents a promising region for palatal implant placements when the midpalatal suture is to be avoided.

Adolescent↗

PubMed2006

Cephalometric facial soft tissue changes with the twin block appliance in Class II division 1 malocclusion patients. A systematic review.

OBJECTIVE: To evaluate facial soft tissue changes after the use of the twin block appliance in Class II division 1 malocclusion patients. MATERIALS AND METHODS: Several electronic databases (PubMed, MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, Cochrane databases, EMBASE, Web of Science, and LILACS) were searched with the help of a senior health-sciences librarian. Abstracts that appeared to fulfill the initial selection criteria were selected by consensus, and the original articles were retrieved. The article references were hand-searched for possible missing articles. Clinical trials that assessed facial soft tissue changes with the use of the twin block appliance without any surgical intervention or syndromic characteristics were considered. A comparable untreated control group was required to factor out normal growth changes. RESULTS: Two articles fulfilled the selection criteria and quantified facial soft tissue changes. Although some statistically significant changes in the soft tissue profile were found, the magnitude of the changes may not be perceived as clinically significant. Changes produced in the upper lip seem to be controversial, although the study with sounder methodological quality did not report significant changes. No change in the anteroposterior position of the lower lip and the soft tissue menton or improvement of the facial convexity was found. CONCLUSIONS: Three-dimensional quantification of the soft tissue changes is required to overcome current limitations in our understanding of the soft tissue changes obtained after the use of the twin block appliance in Class II division 1 malocclusion patients.

Cephalometry↗

PubMed2006

Meta-analysis of immediate changes with rapid maxillary expansion treatment.

BACKGROUND: The authors conducted a literature review to evaluate immediate transverse, anteroposterior, and vertical dental and skeletal changes produced by rapid maxillary expansion (RME). TYPES OF STUDIES REVIEWED: The authors reviewed clinical trials that assessed immediate dental and/or skeletal changes after RME using cephalometric analysis, model casts or both. No surgical or other simultaneous treatment was accepted during the evaluation period. RESULTS: The authors searched electronic databases and found 31 articles that met the initial inclusion criteria. The authors later rejected 12 of these articles because they did not report immediate changes, three because they lacked detailed descriptions of their results and two because of their nonconventional appliance designs. Fourteen articles satisfied th final inclusion criteria; however, they had methodological deficiencies. CLINICAL IMPLICATIONS: The greatest changes resulting from RME in the studies analyzed were dental and skeletal transverse changes. Few vertical and anteroposterior immediate changes were statistically significant, though they probably are not clinically important.

Cephalometry↗

PubMed2006

An evaluation of search and selection methods used in dental systematic reviews published in English.

BACKGROUND: Increasing numbers of systematic reviews are published each year, though little has been done to evaluate their search and selection methodology. METHODS: The authors searched dental systematic reviews published between Jan. 1, 2000, and July 14, 2005, for descriptions of how researchers used multiple electronic databases and secondary searches. They evaluated search and selection methods of identified systematic reviews against the guidelines found in the 2005 Cochrane Handbook for Systematic Reviews of Interventions. RESULTS: The authors identified 220 unique dental systematic reviews. They found that all aspects of search and selection methodology had improved. In 2005, most systematic reviews documented database names and search dates (90 percent), electronic search terms (95 percent) and inclusion-exclusion criteria (95 percent), and most employed secondary searching (100 percent). Many still failed to search more than MEDLINE (20 percent), document the search strategy (20 percent), use multiple reviewers for selecting studies (25 percent) and include all languages (39 percent). CONCLUSIONS AND CLINICAL IMPLICATIONS: Systematic review methodology is improving, though key components frequently are absent. Reviews should be read critically and in consideration of the methodological flaws.

Databases, Bibliographic↗

PubMed2006

The association between head and cervical posture and temporomandibular disorders: a systematic review.

AIMS: To carry out a systematic review to assess the evidence concerning the association between head and cervical posture and temporomandibular disorders (TMD). METHODS: A search of Medline, Pubmed, Embase, Web of Science, Lilacs, and Cochrane Library databases was conducted in all languages with the help of a health sciences librarian. Key words used in the search were posture, head posture, cervical spine or neck, vertebrae, cervical lordosis, craniomandibular disorders or temporomandibular disorders, temporomandibular disorders, and orofacial pain or facial pain. Abstracts which appeared to fulfill the initial selection criteria were selected by consensus. The original articles were retrieved and evaluated to ensure they met the inclusion criteria. A methodological checklist was used to evaluate the quality of the selected articles and their references were hand-searched for possible missing articles. RESULTS: Twelve studies met all inclusion criteria and were analyzed in detail for their methodology and information quality. Nine articles that analyzed the association between head posture and TMD included patients with mixed TMD diagnosis; 1 article differentiated among muscular, articular, and mixed symptomatology; and 3 articles analyzed information from patients with only articular problems. Finally, 2 studies evaluated the association between head posture and TMD in patients with muscular TMD. Several methodological defects were noted in the 12 studies. CONCLUSION: Since most of the studies included in this systematic review were of poor methodological quality, the findings of the studies should be interpreted with caution. The association between intra-articular and muscular TMD and head and cervical posture is still unclear, and better controlled studies with comprehensive TMD diagnoses, greater sample sizes, and objective posture evaluation are necessary.

Head↗

PubMed2006

Computer and Internet usage by Canadian dentists.

OBJECTIVES: To determine the frequency of computers in Canadian dental offices and to assess their use; to evaluate Internet access and use in Canadian dental offices; and to compare use of computers and the Internet by Canadian dentists, by the general public and by other dental groups. METHODS: An anonymous, self-administered survey of Canadian dentists was conducted by mail. A potential mailing list of 14,052 active Canadian dentists was compiled from the 2003 records of provincial regulatory bodies. For each province, 7.8% of the general dentists were randomly selected with the help of computer software. The surveys were mailed to this stratified random sample of 1,096 dentists. RESULTS: The response rate was 28%. Of the 312 respondents, 4 (1%) were in full-time academic positions, 15 (5%) were not practising, and 9 (3%) provided incomplete data. Therefore, 284 survey responses were available for descriptive analysis. Two hundred and fifty-seven (90%) of the respondents had a computer in their primary practice. Computers were used mainly for administrative tasks (accounting, bookkeeping and scheduling) rather than clinical tasks. Internet access was common (185/250 or 74%), and high-speed Internet access (93/250 or 37%) was increasingly common, judging from the results of previous studies on computer use. The main reasons given for not having in-office Internet access were security or privacy concerns and no reported need for or interest in the service. CONCLUSIONS: Computer use was high in this sample of Canadian dentists, but a small proportion of dental offices remained without computers. Canadian dentists" use of the Internet was greater than that of American dentists, private enterprise and the North American public in general.

Canada↗