Jörg A. Lisson

A retrospective study of hearing, speech and language function in children with clefts following palatoplasty and veloplasty procedures at 18-24 months of age.

Many cleft palate teams currently schedule palatoplasty and veloplasty within the childs first year of life. At Hannover Medical School, palatoplasty and veloplasty are performed at approximately 18-24 months of age. It was questioned which speech and language outcome was achieved and whether it may be influenced by: (1) type and extent of the clefts; (2) velopharyngeal inadequacy; and (3) hearing disorders. A retrospective evaluation of data collected from 1985 to 1993 was performed summarizing receptive and expressive speech and language skills of 370 children aged 4.5 years. Cleft types were unilateral cleft lip and palate (UCLP, 30.0%), bilateral cleft lip and palate (BCLP, 28.7%), cleft hard and soft palate (CP, 21.6%), cleft soft palate (cleft velum, CV, 10.8%), cleft lip and alveolus (CLA, 5.8%) and submucous clefts (SUB, 3.2%). n = 86 had constant normal hearing, and n = 284 had conductive hearing loss > 20 dB (500-4000 Hz). Severe developmental phonology errors were found in 30-50% of children with repaired cleft palate and in less than 8% of patients with CLA and SUB. Posterior compensatory misarticulation was below 15% in the groups UCLP, BCLP, CP, CV and SUB. Nasal resonance and air emission was nearly normal in CLA, but was increased in 27% to 38% of the other cleft types. Children with conductive hearing loss had significantly more and severely affected phonology, morphology, syntax, vocabulary, language comprehension, and auditory perception than normal hearing children. Findings indicated that speech and language function in CLP patients were predominantly related to the hearing status.

Application of a new viscoelastic finite element method model and analysis of miniscrew-supported hybrid hyrax treatment

INTRODUCTION In this study, we aimed to assess the ability of a new viscoelastic finite element method model to accurately simulate rapid palatal expansion with a miniscrew-supported hybrid hyrax appliance. METHODS A female patient received 3-dimensional craniofacial imaging with computed tomography at 2 times: before expansion and immediately after expansion, with the latter serving as a reference model for the analysis. A novel approach was applied to the finite element method model to improve simulation of the viscoelastic properties of osseous tissue. RESULTS The resulting finite element method model was a suitable approximation of the clinical situation and adequately simulated the forced expansion of the midpalatal suture. Specifically, it demonstrated that the hybrid hyrax appliance delivered a force via the 2 mini-implants at the center of resistance of the nasomaxillary complex. CONCLUSIONS The newly developed model provided a suitable simulation of the clinical effects of the hybrid hyrax appliance, which proved to be a suitable device for rapid palatal expansion.

Changes of Vertical Skeletal Morphology in Patients With Complete Unilateral and Bilateral Cleft Lip and Palate

Objective The aim of this retrospective investigation was to qualify and quantify changes of the vertical skeletal morphology during puberty in cleft patients compared with an age-matched noncleft control. Methods Patients with unilateral cleft lip and palate (UCLP; n = 12) and bilateral cleft lip and palate (BCLP; n = 11) who fulfilled strict inclusion criteria according to the Hanover treatment protocol were evaluated by means of cephalometric analysis. Lateral cephalograms were analyzed for each cleft patient at age 10 and 15 and compared with corresponding data of a noncleft control (n = 20). Results and Conclusions It was concluded that a vertical growth impairment of the maxilla is found in patients with cleft lip and palate. The maxilla of cleft patients shows a significant clockwise rotation, whereas the inclination of the mandible shows little difference. Consequently, there is a skeletal superposition of the jaws. The posterior height of the maxilla is significantly shorter in patients both with UCLP and BCLP at T0 and T1. An increase of the anterior height of the mandible is found in the cleft groups.

Transverse changes after surgical closure of complete cleft lip, alveolus and palate.

Abstract Surgery for patients with unilateral (UCLP) and bilateral (BCLP) complete cleft lip, alveolus and palate has a considerable influence upon craniofacial growth. With respect to this, the cleft team at Hannover Medical School has attempted to reduce necessary surgical interventions to labioplasty, palatoplasty and veloplasty. Still, the effects of these operations influence maxillary growth to an extent which requires orthodontic treatment in all patients. This study focuses upon the transverse alterations of the alveolar arch and the deciduous dentition after lip and palate surgery. Dental casts prior to any surgical intervention and after labioplasty and complete palaotoplasty of the hard and soft palate were measured for transverse changes by using anatomical landmarks. The results indicate a significant occurrence of anterior relative to posterior arch width loss for both UCLP and BCLP patients. Orthodontic treatment should be planned and performed with respect to these findings in order to support craniofacial growth and prevent maxillary dental arch deficiency.

Investigation of Craniofacial Morphology in Patients with Hypo- and Oligodontia

Aim:This cephalometric study was performed with the intention to qualify and quantify differences between the craniofacial morphology in persons with congenitally missing teeth (hypo- and oligodontia) in comparison with the craniofacial morphology in persons without missing teeth.Patients and Methods:Lateral cephalograms of 42 (21 female, 21 male) patients were traced. Patient mean age at the time the radiographs were taken was 13.39 ± 7.30 years. The sample was divided into two groups: There were 22 patients in the oligodontia group (11 f, 11 m). The group of those with hypodontia contained 20 persons (10 f, 10 m). The growth study by Riolo et al. [15] served as the control.Results:Patients with congenitally missing teeth compared to those with complete dentition showed reduced maxillary and mandibular length (p < 0.001). The mandible was prognathic, the chin positioned more anteriorly (∠SNB p < 0.05, ∠SNPog p < 0.01). The overall anterior face height was noticeably lower as a result of the shortening of both upper anterior and lower anterior face heights (p < 0.001). Comparison between patients with oligodontia and those with hypodontia revealed statistically significant differences in only two dentoalveolar measurements.Conclusion:There were significant morphologic differences between patients with congenitally missing teeth and patients with complete dentition. Additional differentiation between oligodontia and hypodontia revealed only few differences.ZusammenfassungFragestellung:Die Studie dient der Beantwortung der Frage, ob und inwieweit sich die Schädelmorphologie bei Patienten mit Nichtanlagen (Hypo- und Oligodontie) von der bei Patienten mit vollständiger Bezahnung unterscheidet. Zusätzlich erfolgt eine Differenzierung zwischen Hypodontie und Oligodontie.Patienten und Methode:Es wurden Fernröntgenseitenbilder von 42 Patienten (21 w, 21 m) mit Nichtanlagen ausgewertet. Das Durchschnittsalter der Patienten zum Zeitpunkt der Röntgenaufnahme betrug 13,39 ± 7,30 Jahre. Die Patienten wurden in zwei Gruppen unterteilt: Die Gruppe der Patienten mit Oligodontie umfasste 22 Personen (11 w, 11 m), die mit Hypodontie 20 (10 w, 10 m). Zum Vergleich wurden Werte aus der Wachstumsstudie von Riolo et al. [15] herangezogen.Ergebnisse:Bei Patienten mit Nichtanlagen waren im Vergleich zu Patienten mit vollständiger Bezahnung der Oberkiefer und der Unterkiefer in der Sagittalen verkürzt (p < 0,001). Der Unterkiefer war prognath, das Kinn weiter anterior (∠SNB p < 0,05, ∠SNPog p < 0,01). Die vordere Gesichtshöhe war infolge der Verkürzung der oberen und der unteren Gesichtshöhe deutlich verkleinert (p < 0,001). Die Differenzierung zwischen Hypodontie und Oligodontie ergab keine signifikanten Unterschiede, abgesehen von zwei dentoalveolären Parametern.Schlussfolgerung:Es bestanden signifikante Unterschiede in der Schädelmorphologie zwischen Patienten mit Nichtanlagen und solchen ohne. Eine weitere Differenzierung zwischen Hypo- und Oligodontie ergab nur wenige Unterschiede.

Effects of Class II treatment with a banded Herbst appliance on root lengths in the posterior dentition

INTRODUCTION The aim of this study was a retrospective analysis of posterior teeth in 20 adolescents and young adults with Angle Class II Division 1 malocclusion treated with a banded Herbst appliance to check for inhibited root development and apical root resorption. METHODS Panoramic radiographs were taken of every patient at the beginning and after the completion of functional orthopedic treatment. The magnification of the area of the posterior teeth was determined individually for every radiograph. Then the vestibular lengths of the molars and premolars were assessed metrically. To assess root-length changes, the difference between the lengths of the teeth before and after treatment was calculated. RESULTS After treatment with a banded Herbst appliance, tooth length generally increased in the area of the anchorage. But there was a tendency toward root-length decrease in teeth immediately adjacent to the Herbst fittings in the vestibular roots of both the maxillary first molars (distovestibular, -0.02 ± 2.31 mm; mesiovestibular, -0.06 ± 2.05 mm) and the mandibular first premolars (-0.46 ± 3.53 mm). CONCLUSIONS The banded Herbst appliance might deliver unphysiologic forces to immediate anchor teeth, thereby exposing these to a higher risk of root resorption than in other teeth incorporated into the anchorage either directly via bands or indirectly via occlusal or approximal contacts. Looking at uncompromised root morphology in the area of the anchorage, we believe that early treatment with fixed functional appliances can be predicted to yield better outcomes than late treatment because of the higher biologic tolerance expressed by teeth with an apical latency.

Vertical changes in patients with complete unilateral and bilateral cleft lip, alveolus and palate.

Abstract.Aims and Methods:Twelve UCLP and eleven BCLP patients who had been treated according to the Hanover treatment protocol were evaluated by means of cephalometric analysis and cast measurements. The aim of this investigation was to demonstrate changes in the vertical plane and in incisor position in the course of craniofacial growth compared to age-matched non-cleft controls. Lateral cephalograms and casts were analyzed for each cleft patient at age 10 and 15 and compared with corresponding data of a non-cleft control group (n = 20).Results:A vertical growth impairment of the maxilla was registered in patients with cleft lip, alveolus and palate. The maxilla of the cleft patients showed a significant clockwise rotation while the inclination of the mandible remained virtually unchanged. Both upper and lower incisors, which were significantly retruded at the beginning of the late mixed dentition, could be protruded in the course of craniofacial growth, development of the dentition and treatment, but remained retruded in comparison with the non-cleft controls. The posterior midfacial height was highly significantly shorter in both UCLP and BCLP patients at both evaluation timepoints, whereas the anterior lower jaw height was greater than in the control groupZusammenfassung.Ziel und Methodik:Es wurden 23 nach dem Hannoveraner Konzept behandelte Patienten mit vollständigen Lippen-Kiefer-Gaumen-Spalten (n = 12 einseitig, n = 11 beidseitig) mit Hilfe einer Modell- und Fernröntgenseitenbildanalyse nachuntersucht. Ziel war, die Veränderungen in der Vertikalen sowie der Schneidezahnstellung im Verlauf des Wachstums aufzuzeigen. Hierfür wurden von jedem Probanden jeweils ein Fernröntgenseitenbild und ein Modellpaar im Alter von 10 und 15 Jahren ausgewertet und mit entsprechenden Unterlagen einer Kontrollgruppe (n= 20) ohne LKG-Spalte verglichen.Ergebnisse:Es konnte festgestellt werden, dass bei den untersuchten Spaltpatienten eine gering ausgeprägte Hemmung des Oberkiefers in der Vertikalen bestand. Der Oberkiefer der Spaltpatienten war signifikant retroinkliniert, während die Neigung des Unterkiefers kaum verändert war. Die zu Beginn des späten Wechselgebisses hochsignifikant retrudierten Schneidezähne des Ober- und Unterkiefers konnten im Verlauf des Gesichtsschädelwachstums, der Gebissentwicklung und der Behandlung protrudiert werden, blieben im Vergleich zu Nichtspaltträgern aber retrudiert. Die posteriore Mittelgesichtshöhe war in beiden Gruppen der LKG-Spalten zu beiden Untersuchungszeitpunkten hochsignifikant kleiner, die Unterkieferhöhe dagegen im anterioren Bereich gegenüber der Kontrollgruppe größer.

Comparative Survey of Osteotomized and Nonosteotomized BCLP Patients

OBJECTIVE At Hannover Medical School, treatment of BCLP patients was revised and updated in 1980. The objective of the present study was to evaluate the differences in treatment outcome between BCLP patients treated after the revised concept including infant orthopedics, and BCLP patients who received osteotomy in addition to surgical and orthodontic treatment during childhood. PATIENTS Nine of 48 BCLP patients born between 1980 and 1983 received surgical and orthodontic treatment according to the Hannover concept. They were compared to 9 of 68 adolescent and adult patients from Hannover without this protocol, who underwent maxillary osteotomy and consecutive orthodontic treatment. MAIN OUTCOME MEASURES Comparison of the two groups was made at the end of active orthodontic treatment by cast analysis and lateral cephalometrics to evaluate sagittal, transverse, and vertical changes. RESULTS AND CONCLUSIONS No patient treated using the revised protocol showed characteristics of skeletal angle class III at any stage of investigation. No indication for osteotomy was found in this group. All patients with osteotomy had skeletal angle class III resulting from insufficient midfacial growth. Sagittal and vertical skeletal relations were successfully improved by osteotomy.

The Effect of Premolar Extractions on Incisor Position and Soft Tissue Profile in Patients with Class II, Division 1 Malocclusion*

Objective:The objective of this study was to establish whether and how premolar extraction affects the soft tissue profile and incisor inclination in patients with Angle Class II, Division 1 malocclusion. Our primary intention was to identify differences between patients who had four premolars extracted and those who had only two upper premolars removed during camouflage treatment. Our control group consisted of patients with an Angle Class II, Division 1 treated without extractions.Materials and Methods:These patients’ lateral cephalograms were cephalometrically analyzed before and after treatment. Computer-assisted analysis of the data using Onyx Ceph® was followed by a single-factor variance analysis (one-way ANOVA).Results:Our results demonstrate that patients who have undergone camouflage treatment exhibit significantly more retruded upper central incisors than those with extractions in both jaws, and that their upper incisors are highly significantly more retruded and their mandibles significantly more retrognathic than those of patients who have not undergone extraction therapy.Conclusion:We did not observe that the patients’ profiles did become worse after extraction therapy.ZusammenfassungZiel:Es soll dargestellt werden, ob und wie sich eine Prämolarenextraktion auf das Weichteilprofil und die Schneidezahnneigung bei Patienten mit Angle-Klasse II,1 auswirkt. Vor allem sollen Unterschiede zwischen Patienten, bei denen vier Prämolaren extrahiert wurden, und Patienten, denen im Rahmen einer Camouflage-Behandlung nur zwei Prämolaren im Oberkiefer entfernt wurden, ermittelt werden. Als Vergleichsgruppe dienen Patienten mit einer Angle-Klasse II,1, die ohne Extraktionen behandelt wurden.Material und Methodik:Die Fernröntgenseitenbilder dieser Patienten wurden vor und nach der Behandlung kephalometrisch ausgewertet. Im Anschluss an die computergestützte Auswertung der Daten mit Onyx Ceph® erfolgte eine einfaktorielle Varianzanalyse (Oneway ANOVA).Ergebnisse:Die Ergebnisse zeigen, dass Patienten mit Camouflage-Behandlung nach Therapie signifikant retrudierter stehende obere mittlere Schneidezähne als Patienten mit Extraktionen in beiden Kiefern haben und dass sie höchst signifikant retrudierter stehende obere Schneidezähne sowie signifikant retrognather liegende Unterkiefer als Patienten ohne Extraktionstherapie aufweisen.Schlussfolgerung:Eine Profilverschlechterung nach Extraktionstherapie konnte nicht nachgewiesen werden.

Craniofacial Growth Patterns in Patients with Congenitally Missing Permanent Teeth

Objective:Aim of this study was to investigate any correlations between the congenital absence of certain permanent teeth and individual craniofacial growth patterns.Material and Methods:The lateral cephalograms of n = 101 patients (65 ♀ und 36 ♂) with various congenitally missing teeth were analyzed according to Hasund [11] prior to orthodontic treatment. Cephalometric data to determine the craniofacial growth pattern comprised GntgoAr, NSBa, ML-NSL, NL-NSL, MLNL angles and the index between upper and lower facial heights. Correlations between the type of missing teeth and growth pattern were examined. Group distribution was A = all patients with missing teeth (n = 101), P = missing second premolars (n = 49), S = missing upper lateral incisors (n = 30), X = various missing teeth (n = 22). We included a control group for each of these groups using data from Riolo et al.’s [22] growth study.Results:Group A revealed an even distribution with n = 32 patients (31.7%) having a vertical growth pattern, n = 37 patients (36.6%) a neutral growth pattern, and n = 32 patients (31.7%) a horizontal growth pattern. The majority of patients (n = 20, 40.8%) in group P exhibited a horizontal growth pattern, whereas there were no significant correlations between the kind of congenitally missing teeth and growth patterns in groups S and X. Comparison of the mean values of groups P, S and X, revealed no significant differences. When comparing the control group to groups A, P and S, we noted significantly or highly significantly smaller gonial and basal plane angles. No significant differences were apparent concerning group X.Conclusions:This examination demonstrates no statistically-relevant correlation between craniofacial growth pattern and the congenital absence of certain permanent teeth, although horizontal growth is more frequent (but not significant) in patients with congenitally missing second premolars.ZusammenfassungZiel:Ziel der Untersuchung war es herauszufinden, inwieweit ein Zusammenhang zwischen der Nichtanlage bestimmter permanenter Zähne und der individuellen Wachstumstendenz des Schädels besteht.Material und Methodik:Hierzu wurden die Fernröntgenseitaufnahmen von n = 101 Patienten (65 ♀ und 36 ♂) mit Nichtanlage unterschiedlicher Zähne vor Behandlungsbeginn mit Hilfe der klinischen Kephalometrie nach Hasund [11] analysiert. Zur Bestimmung der Wachstumstendenz wurden die Winkel GntgoAr, NSBa, ML-NSL, NL-NSL, ML-NL und der Index zwischen oberer und unterer Gesichtshöhe vermessen und ausgewertet. Es erfolgte die Einteilung der Patienten in folgende Gruppen: A = alle Patienten (n = 101), P = Nichtanlage zweiter Prämolaren (n = 49), S = Nichtanlage seitlicher oberer Schneidezähne (n = 30), X = Nichtanlage unterschiedlicher Zähne (n = 22). Zu diesen Gruppen wurde jeweils eine Kontrollgruppe mit Vergleichswerten aus der Wachstumsstudie von Riolo et al. [22] erstellt und zum Vergleich herangezogen.Ergebnisse:In Gruppe A wiesen n = 32 Patienten (31,7%) einen vertikalen Wachstumstyp auf. Eine annähernd gleiche Anzahl von Patienten (n = 37) zeigte mit 36,6% ein ausgeglichenes Kieferwachstum. Dagegen hatten n = 32 Patienten (31,7%) ein eindeutig horizontales Wachstumsmuster. Die Mehrheit der Gruppe P (n = 20) hatte mit 40,8% ein horizontales Wachstumsmuster, während in den Gruppen S und X keine signifikanten Unterschiede zwischen der Art der nicht angelegten Zähne und dem Wachstumstyp vorlagen. Die Mittelwerte der Gruppen untereinander zeigten keine signifikanten Unterschiede. Im Vergleich der Kontrollgruppe mit den Gruppen A, P und S waren der Kieferwinkel und der Kieferbasiswinkel signifikant bis hochsignifikant kleiner. Zur Gruppe X konnten keine signifikanten Unterschiede festgestellt werden.Schlussfolgerungen:Die Untersuchung ergab keinen statistisch relevanten Zusammenhang zwischen der individuellen Wachstumstendenz des Schädels und der Nichtanlage bestimmter permanenter Zähne. Lediglich bei Patienten mit Nichtanlage der zweiten Prämolaren war ein vermehrtes, aber nicht signifikantes horizontales Wachstumsmuster festzustellen.