Derya Germec-Cakan

Cortical bone thickness of the alveolar process measured with cone-beam computed tomography in patients with different facial types.

INTRODUCTION The purpose of this study was to determine the cortical bone thickness of the alveolar process in the maxilla and the mandible on cone-beam computed tomographs of adults with low, normal, and increased facial heights. METHODS This study was conducted on 155 images of adult patients (20-45 years old) who were assigned to the low-angle, normal, and high-angle groups. The thickness of the buccal cortical plates of the maxilla and the mandible, and the palatal cortical plates of the maxilla, were measured. RESULTS There was no statistically significant difference between the groups regarding mean ages, sex, and sagittal facial types. High-angle patients had significantly lower values than did low-angle patients in all mini-implant insertion sites in both the maxillary and mandibular alveolar bones. The mandibular and maxillary buccal measurements showed a similar pattern; the lowest values were for the high-angle group, followed by the normal group; the highest values were measured in the low-angle patients. CONCLUSIONS Clinicians should be aware of the probability of thin cortical bone plates and the risk of mini-implant failures at maxillary buccal alveolar mini-implant sites in high-angle patients, and at mandibular buccal alveolar mini-implant sites between the canine and the first premolar in normal and high-angle patients.

Uvulo-glossopharyngeal dimensions in non-extraction, extraction with minimum anchorage, and extraction with maximum anchorage

The aim of this study was to investigate upper respiratory airway dimensions in non-extraction and extraction subjects treated with minimum or maximum anchorage. Lateral cephalograms of 39 Class I subjects were divided into three groups (each containing 11 females and 2 males) according to treatment procedure: group 1, 13 patients treated with extraction of four premolars and minimum anchorage; group 2, 13 cases treated non-extraction with air-rotor stripping (ARS); and group 3, 13 bimaxillary protrusion subjects treated with extraction of four premolars and maximum anchorage. The mean ages of the patients were 18.1 ± 3.7, 17.8 ± 2.4, and 15.5 ± 0.88 years, respectively. Tongue, soft palate, hyoid position, and upper airway measurements were made on pre- and post-treatment lateral cephalograms and the differences between the mean measurements were tested using Wilcoxon signed-ranks test. Superior and middle airway space increased significantly (P < 0.05) in group 1. In group 2, none of the parameters showed a significant change, while in group 3, middle and inferior airway space decreased (P < 0.01). The findings show that extraction treatment using maximum anchorage has a reducing effect on the middle and inferior airway dimensions.

Comparison of Facial Soft Tissue Measurements on Three-dimensional Images and Models Obtained With Different Methods

Aim:The aim of this study was to compare the clinical facial soft tissue measurements with the measurements of facial plaster cast, three-dimensional scanned facial plaster cast, 3-dimensional digital photogrammetrical images, and three-dimensional laser scanner images. Materials and Methods:Three-dimensional facial images of 15 adults were obtained with stereophotogrammetry and a three-dimensional laser scanner. Facial models of subjects were obtained using silicone impression and were scanned. Landmarks were marked on the subjects and plaster casts, digitized on three-dimensional models, and measured in Mimics 12.0 software (Materialises Interactive Medical Image Control System, Leuven, Belgium). Results:No statistically significant differences were found between all three-dimensional measurement methods in mouth width, philtrum median height, and nasal width. Comparison of clinical measurements with facial plaster cast measurements revealed that philtral width, nasal tip protrusion, and right lip and nostril heights were wider and longer in clinical measurements than in facial plaster cast measurements. Comparison of clinical measurements to the laser scanned and stereophotogrammetric model measurements revealed that philtrum lateral and lip heights and philtral width were significantly different between methods. When laser scanned and stereophotogrammetric measurements were compared, significant differences were observed in lip and nostril heights. Conclusions:Facial impression may be problematic owing to the depression caused by the impression material especially on the tip of the nose. Laser scanning is not sensitive enough to visualize the deeper indentations such as nostrils. Stereophotogrammetry is promising for three-dimensional facial measurements and even will be better when color identification between mucocutaneous junctions of the lip region is achieved.

Arch-width and perimeter changes in patients with borderline Class I malocclusion treated with extractions or without extractions with air-rotor stripping

INTRODUCTION The aim of this study was to compare dental arch-width and perimeter changes in patients with borderline Class I occlusion, treated with extractions or without extractions with air-rotor stripping (ARS). METHODS The study was conducted with 26 sets of pretreatment and posttreatment dental models of patients with borderline Class I occlusion. Thirteen patients (mean age, 18.1 +/- 3.7 years) were treated with 4 premolar extractions, and 13 (mean age, 17.8 +/- 2.4 years) were treated without extractions but with the ARS technique. Mean maxillary and mandibular crowding values were 5.7 +/- 1.5 and 5.9 +/- 1.4 mm in the extraction group, and 5.0 +/- 1.3 and 5.9 +/- 1.3 mm in the nonextraction group, respectively. A digital caliper was used to measure maxillary and mandibular intercanine and intermolar arch widths and arch perimeters. The Wilcoxon test was used to evaluate treatment changes in each group. The Mann-Whitney U test was used to compare the pretreatment and posttreatment values and the treatment changes between the 2 groups. RESULTS At the start of treatment, the maxillary and mandibular intercanine and intermolar widths and the arch perimeters of both groups did not differ statistically. The maxillary intercanine widths were maintained in both groups. The maxillary and mandibular intermolar widths and arch perimeters decreased in the extraction group. In the nonextraction group, intermolar widths decreased, but arch perimeters did not change significantly. After treatment, the maxillary and mandibular intercanine widths were not different between the groups. CONCLUSIONS In Class I borderline patients with moderate crowding, extraction therapy with minimum anchorage did not result in narrower dental arches, and nonextraction treatment with ARS preserved the intercanine arch widths and arch perimeters.

Evaluation of metal concentrations in hair and nail after orthognathic surgery.

Introduction:Titanium miniplates are widely used in orthognathic surgery. Titanium is considered to be a bioinert material, although its long-term accumulation in distant human tissues is unclear. The study was designed to evaluate the concentrations of aluminum (Al), titanium (Ti), and vanadium (V) in the hair and nail of patients who underwent orthognathic surgery. Methods:The study group comprised 20 patients who had had orthognathic surgery minimum 14 and maximum 96 months previously (mean [SD], 54.7 [3.5] mo). Miniplates and miniscrews were made of Ti-6Al-4V alloys (Trimed, Ankara, Turkey). The control group comprised 10 healthy adults not operated on. Metal concentrations in the hair and nail of the subjects were measured by inductively coupled plasma mass spectroscope (Thermo Elemental X7 series; Thermo Electron, London, England). Descriptive statistical methods were used for data analysis, and Mann-Whitney test was used to compare both groups. Results:Concentrations of Al, Ti, and V in the hair of the study group were significantly higher than those in the control group (P < 0.001). Nail Ti and V concentrations of the study group were also significantly higher than those of the control group (P < 0.001 and P < 0.01, respectively). Nail Al concentration was similar in both groups (P > 0.05). Conclusions:Increased corrosive element concentrations may be observed in the hair and nail of patients who underwent orthognathic surgery.

Interdisciplinary treatment of a patient with bilateral cleft lip and palate and congenitally missing and transposed teeth

The comprehensive treatment of a patient with cleft lip and palate requires an interdisciplinary approach for functional and esthetic outcomes. A 20-year-old woman with bilateral cleft lip and palate had a chief complaint of unesthetic appearance of her teeth and the presence of oronasal fistulae. Her clinical and radiographic evaluation showed a dolichofacial growth pattern, a Class II skeletal relationship with retroclined maxillary central incisors, 5 mm of negative overjet, maxillary constriction, maxillary and mandibular crowding, congenitally missing maxillary right incisors and left lateral incisor, and a transposed maxillary left canine. Her treatment plan included the extraction of 3 premolars, maxillary expansion, segmental maxillary osteotomy, repair of the oronasal fistulae, rhinoplasty, periodontal surgery, and prosthodontic rehabilitation. To obtain a better occlusion and reduce the dimensions of the fistulae, orthognathic surgery comprising linear and rotational movements of the maxillary segments (premaxilla, right and left maxillary alveolar segments) in all 3 axes was planned by performing 3-dimensional virtual surgery on 3-dimensional computerized tomography. At the end of the interdisciplinary treatment, a functional occlusion, a harmonious profile, and patient satisfaction were achieved. Posttreatment records after 1 year showed stable results.

Three-dimensional evaluation of alveolar bone thickness of mandibular anterior teeth in different dentofacial types

Aim: The aim of this randomized study was to compare the alveolar bone thickness (ABT) of the mandibular incisor teeth of dental and skeletal Class I, II, and III adult patients at labial and lingual aspects of the bone and develop recommendations for the associated movements of teeth in this region, taking vertical facial type into consideration. Material and Methods: Sixty-two Class I, 74 Class II, and 63 Class III patients - aged between 20 and 45 - were assigned to three subgroups – high (H), low (L), and normal (N) growth patterns. On the axial slices of computerized tomographies, the measurements for the ABT on labial and lingual sides of the mandibular incisors were carried out at three levels. Results: In Class I group, at apex region, ABT of subgroups N and L were greater than H, at labial side. In Class II, ABT of subgroups N and L were greater than H, at apex at both sides and cervical lingual region. Similarly, ABT of subgroup L of Class III group was greater than H, at labial and lingual apex, mid-root regions. In Class II, the ABT of subgroup H was greater than L, at lingual cementoenamel junction. Conclusions: ABT of mandibular incisors of Class I patients is not affected from vertical pattern except for apical region. There is not a thick bone on the lingual side of the Class II, high-angle patients. The ABT of the Class III, high-angle patients is thin as a risk factor for proclination.

Clear double layer Bioplast feeding plate for neonates with cleft palate

An infant with cleft palate was referred to cleft clinic of the Orthodontic Department. The mother was concerned to feed the child because of the escape of milk from the nose. Intraoral examination revealed a large palatal cleft extending from hard to soft palate involving uvula. The impression was taken and dental cast obtained. A 3 mm soft and afterward a 1 mm hard Bioplast plate was pressed using Biostar device (Scheu-Dental Gmbh, Iserlohn, Germany) on the model. Finally, a hole was prepared on the anterior part to put a thread through it. The infant tolerated the plate immediately and encounters no difficulties during feeding. The inlaying soft Bioplast plates eliminate the risk of tissue irritation, whereas the covering hard Bioplast plate supplies endurance. The fabrication of the clear Bioplast feeding plate is easy and less time-consuming compared with acrylic plates and may be recommended in crowded and overloaded cleft centers.