Biomedical subjects

Ceib L Phillips

Publications and source records attributed to Ceib L Phillips.

4 recordsLinked to original sources

PubMed2007

Three-dimensional cone-beam computed tomography for assessment of mandibular changes after orthognathic surgery.

INTRODUCTION: The purpose of this study was to assess alterations in the 3-dimensional (3D) position of the mandibular rami and condyles in patients receiving either maxillary advancement and mandibular setback or maxillary surgery only. METHODS: High-resolution cone-beam computed tomography scans were taken of 21 patients before and after orthognathic surgery. Ten patients with various malocclusions underwent maxillary surgery only, and 11 Class III patients received maxillary advancement and mandibular setback. Presurgery and postsurgery 3D models were registered on the surface of the cranial base. A new tool was used for graphical overlay and 3D display with color maps to visually assess the locations and to quantify positional changes in the posterior border of the mandibular rami and condyles between superimposed models. RESULTS: The average displacements in condylar position were small--0.77 mm (SD, 0.12 mm) and 0.70 mm (SD, 0.08 mm)--for 2-jaw and 1-jaw surgeries, respectively (not significant, P >.05). All 2-jaw surgery patients had backward rotational displacements of the mandibular rami (mean, 1.98 mm; SD, 1.03 mm), with a maximum surface distance change of > or =2 mm in 8 of 11 subjects. For the 1-jaw surgery, all subjects had small backward rotational displacements of the mandibular rami (mean, 0.78 mm; SD, 0.25 mm), with only 1 subject having a maximum surface distance change > or =2 mm. The difference in mean backward rotational displacement was statistically significant (P <.01). CONCLUSIONS: The visualization of 3D model superimposition clearly identified the location, magnitude, and direction of mandibular displacement. The 3D imaging allowed quantification of vertical, transverse, and anteroposterior ramus displacement that accompanied mandibular, but not maxillary only, surgery.

Adult↗

PubMed2005

Variation in dental and skeletal open bite malocclusion in humans with amelogenesis imperfecta.

The amelogenesis imperfectas (AI) are a diverse group of genetic disorders primarily affecting the quality and or quantity of enamel, however, affected individuals often have an open bite malocclusion. Three main AI types are recognized based on the perceived developmental mechanisms involved and the enamel phenotype. The purpose of this investigation was to evaluate the association of the AI enamel defect with craniofacial features characteristic of an open bite malocclusion. The sample consisted of 54 AI affected and 34 unaffected family members from 18 different kindreds. Lateral cephalograms were digitized and measurements evaluated for vertical plane alterations using Z-scores. Forty two percent of AI affected individuals and 12% of unaffected family members had dental or skeletal open bite malocclusions. Skeletal open bite malocclusion was variably expressed in AI affected individuals. The enamel phenotype severity did not necessarily correspond with the presence or severity of open bite malocclussion. Open bite malocclusion occurred in individuals with AI caused by mutations in the AMELX and ENAM genes even though these genes are considered to be predominantly or exclusively expressed in teeth. Affected AI individuals with cephalometric values meeting our criteria of skeletal open bite malocclusion were observed in all three major AI types. The pathophysiological relationship between AI associated enamel defects and open bite malocclusion remains unknown.

Adolescent↗

PubMed2004

Analgesic safety and efficacy of diclofenac sodium softgels on postoperative third molar extraction pain.

PURPOSE: The purpose of this single-blind, placebo-controlled, 3-arm parallel, randomized study was to compare the analgesic efficacy and tolerability of a single dose of 100 mg diclofenac potassium (Cataflam; Novartis, Stein, Switzerland), 100 mg diclofenac sodium softgel, and placebo in patients experiencing moderate to severe postoperative pain after third molar extraction. PATIENTS AND METHODS: Seventy-five patients (67% female with a mean age of 23, age range 18 to 34.5 years) participated in the study following removal of at least 1 impacted mandibular third molar. Patients received a single dose of study medication when their postoperative pain reached a moderate or severe intensity. Analgesic efficacy measures included the time to meaningful pain relief measured using a stopwatch and time to rescue medication. Pain relief (PR) and Pain intensity (PI) ratings were recorded at 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 4, 5, 6, 8, and 24 hours postdosing. Summary analgesic measures, including Summed Pain Relief Score (TOTPAR) and Summed Pain Intensity Differences (SPID), were calculated from the 0.25- to 6-hour responses. The time between pain relief and rescue and a global evaluation for the effectiveness of the study medications were recorded at the end of the study. Seven scheduled blood samples were collected from each patient for determining plasma concentrations of diclofenac anion. RESULTS: Both diclofenac sodium softgel and Cataflam were significantly more effective than placebo (P <.0001) for all summary analgesic measures. The average overall pain relief was substantially better from diclofenac sodium softgel than from Cataflam, but the difference was not statistically significant (P =.14). In patients taking diclofenac sodium softgel, 50% of the patients experienced a time to onset of analgesic activity within 18 minutes and the median analgesic duration was 5 hours (302 minutes). Fifty percent of the patients taking Cataflam had a time to onset of action within 38 minutes, and the median duration of analgesia was 4.5 hours (272 minutes). At the time of rescue drug administration or 6 hours, whichever was earlier, 72% of the patients given diclofenac sodium softgel rated the medication as a very good or excellent pain reliever, whereas only 45% of the patients taking Cataflam gave these ratings. No serious adverse events were observed in this study. The mean concentrations of diclofenac from the diclofenac sodium softgel formulation were significantly different from the Cataflam formulation. The mean C(max) for the softgel was almost twice that of Cataflam and C(max) was reached an hour earlier, on average. CONCLUSIONS: More diclofenac anion was absorbed at a quicker rate using the formulation diclofenac sodium softgel 100 mg than Cataflam. The softgel provided a very rapid onset of analgesic activity, a prolonged analgesic duration, and an acceptable side-effect profile in the postoperative third molar surgery pain model. In an acute pain situation, the rapid absorption of nonsteroidal anti-inflammatory drugs from a formulation like the Softgel may positively affect the time of onset and duration of inflammatory pain compared with other commercially available nonsteroidal anti-inflammatory drug formulations.

Adolescent↗

PubMed2002

Analysis of craniofacial development in children with hypohidrotic ectodermal dysplasia.

Ectodermal dysplasias (ED) are a heterogeneous group of inheritable disorders characterized by abnormal development of embryologic ectoderm derivatives. The purposes of this study were to: 1) create baseline cephalometric norms for male children with ED; 2) assess craniofacial growth and development in hypohidrotic ED male children with severe hypodontia, compared with non-ED children with class I dental relationships; 3) compare the craniofacial morphology of titanium dental implant-treated ED males with non-implant-treated ED males; and 4) correlate the severity of hypodontia to craniofacial dysmorphology. Cephalometric radiographs of class I individuals and implant-treated and nontreated ED groups were used to evaluate craniofacial morphology. Traditional cephalometric landmarks and measurements were used to compare groups using the generalized estimate equation analysis. Age, gender, and the number of permanent maxillary teeth present had a significant (P =.01) explanatory relationship with the craniofacial measures when comparing untreated ED children to norms. Mean craniofacial differences between ED and non-ED children still existed when the explanatory effects of these variables were controlled, indicating dysmorphology in several craniofacial structures (e.g., cranial base, mandibular length). The number of missing maxillary permanent teeth was significantly related with craniofacial dysmorphology in the ED population. Craniofacial morphology did not differ significantly between implant-treated and nontreated ED children, suggesting that treatment with intraosseous dental implants, as applied in this population, did not rescue normal craniofacial growth and development.

Adolescent↗