Ali Kiki

Condylar asymmetry in unilateral posterior crossbite patients

INTRODUCTION Posterior crossbite is defined as an abnormal buccolingual relationship between opposing posterior teeth including the canines in centric occlusion. The most common form of posterior crossbite is unilateral with a functional shift of the mandible toward the crossbite side. Lateral shift of the mandible in functional crossbite patients results in mandibular skeletal deflection to the crossbite side. Thus, the asymmetrical position of the mandible in these patients can result in asymmetrical condylar heights. The purpose of this study was to investigate condylar and ramal asymmetries in unilateral crossbite patients as compared with normocclusive subjects. METHODS The study groups included 81 patients with unilateral posterior crossbite and a control group of 75 patients with normal occlusion. Condylar, ramal, and condylar-plus-ramal asymmetry values were computed for all subjects on panoramic radiographs. Data were analyzed statistically with ANOVA for repeated measures and univariate ANOVA. RESULTS The patients with unilateral posterior crossbite had more asymmetric condyles than did the controls. In addition, condylar, ramal, and condylar-plus-ramal heights on the crossbite side were smaller than those on the noncrossbite side. CONCLUSIONS Subjects with functional unilateral posterior crossbite have asymmetrical condyles.

A comparison of dentoalveolar inclination treated by two palatal expanders.

The objective of the present study was to evaluate buccal dentoalveolar inclinations in subjects treated with a Hyrax (tooth-borne) or acrylic-bonded (tooth-tissue borne) palatal expander. The sample comprised 39 patients (10 males and 29 females) aged between 11 and 16 years randomly assigned to two groups. Rapid maxillary expansion (RME) was carried out with a Hyrax appliance in one group (n = 21) and with an acrylic-bonded appliance in the other (n = 18). Their mean ages were 13 years 9 months and 13 years 6 months, respectively. Orthodontic study models were obtained before RME (T1) and approximately 1 week after completion of maxillary expansion (T2). A line of barium sulphate solution was drawn between the upper first molars on the models, and radiographs were taken. The radiographic images of the models were transferred to digital medium, and buccal tipping of the molar crowns and alveolar processes were evaluated by means of a software program. The data were analysed by paired and Students t-tests. Both RME appliances produced significant (P < 0.001) dentoalveolar tipping during RME, but this was greater in the Hyrax group (P < 0.05).

Condylar asymmetry in bilateral posterior crossbite patients.

OBJECTIVE To investigate whether patients with bilateral posterior crossbite have asymmetrically developed condyles. MATERIALS AND METHODS The study group consisted of 75 patients with bilateral posterior crossbite, and a control group of 75 subjects with normal occlusion. Condylar, ramal, and condylar plus ramal asymmetry values were computed for all of the subjects on orthopantomograms. Data were analyzed statistically by means of paired t-test and Students t-test. RESULTS The patients with bilateral posterior crossbite had more asymmetrical condyles relative to the controls. However, there were no statistically significant differences in condylar, ramal, or condylar plus ramal heights between left and right sides in both the control and crossbite groups. CONCLUSION Patients with bilateral posterior crossbite can have asymmetrical condyles and might be at risk for the development of future skeletal mandibular asymmetries.

Soft tissue profile changes following maxillary protraction in Class III subjects

SUMMARY The dentoskeletal effects of maxillary protraction (MP) therapy have been extensively investigated, while those relating to soft tissue profile changes are limited. Thus, the aim of this study was to determine the degree of soft tissue profile changes following MP therapy. The material consisted of the cephalometric films of 24 female subjects (12.69 +/- 1.08 years) with a Class III malocclusion who underwent MP therapy; these were compared with a control group of 15 females (12.13 +/- 0.63 years) with a Class I occlusion and matched for chronological age and observation period. Cephalometric films were available for all subjects before (T1) and after (T2) treatment/observation. The initial measurements and treatment/control changes were compared between the groups by means of a Students t-test. The subjects in the MP group had a concave facial profile when compared with the controls. Comparison of the changes induced by MP therapy showed that the maxilla and surrounding soft tissues showed significant anterior movement (P < 0.001), whereas the mandible and surrounding soft tissues showed a backward and downward rotation. The improvement in facial profile predominantly resulted from maxillary soft tissue changes and mandibular hard tissue changes. The concave soft tissue profiles of the Class III subjects were corrected by anterior movement of the maxilla and a concomitant increase in the fullness of the upper lip. The concave skeletal profiles were, however, corrected mainly by backward and downward rotation of the mandible.

Effects of rapid maxillary expansion on Holdaway soft tissue measurements

The objective of the present study was to evaluate short-term soft tissue changes caused by rapid maxillary expansion (RME) in 18 subjects (15 females and 3 males) (mean age 13 years 6 months) with a bilateral posterior crossbite. Lateral cephalograms of the patients were obtained at three different time points: before RME (T1), after maxillary expansion (mean = 0.82 month) (T2), and after retention (mean = 5.95 months) (T3). Holdaway soft tissue measurements were used for the evaluation of soft tissue changes. Data were analysed statistically by means of paired t-tests. The facial soft tissue angle decreased (P < 0.05), and H angle and skeletal profile convexity increased significantly (P < 0.001) at T2. During T3, the increase in the facial soft tissue angle and the decrease in H angle were minimal and not significant, while skeletal profile convexity significantly decreased (P < 0.001). The results of this study indicate that RME may affect Holdaway soft tissue measurements.

Maxillary expansion with the memory screw: a preliminary investigation

Objective The purpose of this study was to investigate the effects of a newly developed rapid maxillary expansion screw-the memory screw-over 6 months. Methods Five subjects, aged between 11.7 and 13.75 years, were enrolled in this study. All subjects underwent placement of a maxillary expansion appliance containing superelastic nickel-titanium open-coil springs in its screw bed. The parents of the patients and/or the patients themselves were instructed to activate the expansion screw by 2 quarter-turns 3 times a day (morning, midday, and evening; 6 quarter-turns a day). The mean expansion period was 7.52 ± 1.04 days. Dentoskeletal effects of the procedure, including dentoalveolar inclination, were evaluated. Measurements of all the parameters were repeated after 6 months of retention in order to check for relapse. Results Sella-Nasion-A point (SNA) and Sella-Nasion/Gonion-Menton angles increased, and Sella-Nasion-B point (SNB) angle decreased in all the subjects during the expansion phase. However, they approximated to the initial values at the end of 6 months. On the other hand, the increments in maxillary apical base (Mxr-Mxl) and intermolar widths was quite stable. As expected, some amount of dentoalveolar tipping was observed. Conclusions The newly developed memory expansion screw offers advantages of both rapid and slow expansion procedures. It widens the midpalatal suture and expands the maxilla with relatively lighter forces and within a short time. In addition, the resultant increments in the maxillary apical base and intermolar width remained quite stable even after 6 months of retention.

Palatinale gömülü maksiller kanin dişlerin sabit ve hareketli apareyler ile sürdürülmesi: olgu sunumu

Ust cene on bolge dislerinin surme bozukluklari, yuz estetigini olumsuz yonde etkileyen bir klinik problemdir. Gomulu dislerin ark icindeki ideal yerlerine ortodontik olarak surdurulmesi ve dizilmesi hastaya daha iyi bir gulumseme saglamaktadir. Bu amac dogrultusunda, klinisyenin en iyi ortodontik mekanigi secmesi gerekmektedir. Bu calismada palatinale gomulu maksiller kaninlerin surdurulmesi amaciyla kullanilan ortodontik ve cerrahi tedavi secenekleri anlatilmis ve palatinal pozisyonda gomulu maksiller kanin dislerinin sabit ve hareketli ortodontik aygitlarla surduruldugu iki olgu ve bu mekaniklerin avantaj ve dezavantajlari sunulmustur. Sunulan ikinci olguda retansiyon kroseleri ve helikal springleri olan basit ve etkili muteharrik aparey ile gomulu dislerin surduruldugu yeni bir yontem anlatilmistir. Anahtar kelimeler: Palatinale gomulu maksiller kaninler, ortodontik surdurme, sabit ortodontik mekanikler, hareketli ortodontik apareyler, avantaj ve dezavantaj. Abstract Eruption anomalies of maxillary anterior teeth are clinical problem which effects facial esthetics. Forced eruption and alignment of impacted teeth into the arch is the best treatment approach and supply a more estetic smile for patient. For this purpose, clinician should be selecting the best ideal orthodontic mechanics. In this study presented that orthodontics and surgery treatment options was evaluated used for forced eruption of palatally impacted maxillary canines and on two cases that is forced eruption of palatally impacted maxillary canines used with fixed and removable orthodontics mechanics and explain that advantages and disadvantages of this mechanics. In the present two case explained new method that is an effective and simple removable appliance for the forced eruption of impacted teeth which included retention clasps and a helical spring. Key words: Palatally impacted maxillary canines, forced eruption, fixed orthodontic mechanics, removable orthodontic appliance, advantage and disadvantages