Cornelius Klein

Lengthening of the hypoplastic mandible by gradual distraction in childhood — a preliminary report

Uni- or bilateral mandibular hypoplasia can be associated with various syndromes or is acquired after early traumatic or inflammatory disease in the temporomandibular joint (TMJ). Early treatment is necessary to avoid consequent impairment of midfacial growth. The standard treatment of these malformations consists of the application of bone grafts which can lead to unpredictable growth. Furthermore, these procedures often require intermaxillary fixation and sometimes blood transfusions. Lengthening of the mandible by gradual distraction, according to the method of Ilizarov, opens new perspectives for interceptive therapy. This paper reports on this method applied in 9 cases of mandibular hypoplasia. Out of 3 bilateral and 6 unilateral mandibular distractions the average amount of bone lengthening was 21 mm, ranging from 15 to 25 mm. In order to facilitate ossification, the mandibles were maintained in external fixation for an average of 9 weeks subsequent to the period of active lengthening. Thereafter, immediate postoperative orthodontic treatment is necessary to avoid a relapse. No complications were noted during the follow-up period (max 17 months).

Correction of mandibular hypoplasia by means of bidirectional callus distraction.

The method of gradual callus distraction proved to be very useful in augmenting hypoplastic mandibles. When performing our first series using a unidirectional distractor, we faced some problems in determining the direction of lengthening. Moreover, postoperative adjustments were not possible. On the basis of this experience, we developed a bidirectional lengthening device consisting of two limbs and a variable angulation piece. This allows distinct control of the vertical and horizontal components of the distraction. The method proved effective and reliable in 18 patients with various degrees of mandibular hypoplasia. The median follow-up period was 10 months (range, 1–19 months).

Reliable Surgically Assisted Rapid Palatal Expansion by Maxillary Widening Device

For surgically assisted rapid palatinal expansion, bone-borne as well as tooth-borne devices to widen the maxilla are commonly used, both revealing advantages and disadvantages. In the area of bone-borne devices, several new designs have been introduced during the last years as an alternative to the tooth-borne Biederman-Hyrax screw. However, with these new distractors, new problems occurred. Therefore, we designed the Maxillary Widening Device (MWD; Normed, Tuttlingen, Germany), a new bone-borne distractor, being not only user-friendly but also universally applicable. We have used this device since 2005 in patients with upper jaw compression, and the MWD turned out to be easy and quick to insert. Using a minimal surgical approach such as the modified Le Fort I osteotomy, operation time was low. Fixating as well as activating the distraction cylinder turned out to be very user-friendly. The removal of the device after the retaining period was also unproblematic, and the later forming of the dental arch was good to satisfying in all patients.

Erste Erfahrungen mit einem neuen Distraktionsimplantatsystem zur Kieferkammaugmentation

Zusammenfassung Die kaufunktionelle Rehabilitation eines Patienten ist nicht zuletzt von der Qualität und dem Volumen des vorhandenen Kieferknochens abhängig. Volumenverluste nach tumorbedingten Unterkieferkastenresektionen oder altersabhängige Atrophien können hier erhebliche Probleme bereiten. Ersatzplastiken mit freiem Beckenkamm, Tabula externa oder Sandwich-Plastiken sind nur einige Beispiele für die bislang üblichen chirurgischen Behandlungsverfahren. Unter Verzicht auf Knochentransplantate könnte die Kieferkammaugmentation mit Hilfe der Distraktionsosteogenese hier einen wertvollen Beitrag zur Verbesserung des Prothesenlagers liefern. Es werden ein neues, implantatgestütztes System zur vertikalen Knochendistraktion vorgestellt und über einen ersten klinischen Einsatz anhand einer Einzelfallbeschreibung berichtet. Nach einer anterioren Segmentosteotomie wurden 2 Distraktionsimplantate inseriert, dann der Kieferkamm täglich um 1 mm bis zur gewünschten Augmentation um 8 mm angehoben. Nach einer 4wöchigen Latenzphase zur Frühossifikation des Kallus wurden dann die Distraktionsimplantate durch definitive enossale Implantate ersetzt. Insgesamt hat uns die klinische Anwendung ermutigt, den hier begonnenen Weg fortzusetzen. Implantatsystem und Operationstechnik werden erläutert, die Ergebnisse diskutiert. Summary The masticatory rehabilitation of patients is dependent on the quality and volume of residual jaw bone. Loss of volume caused by tumor-related mandibular ridge resection or age-related atrophies may cause considerable problems. Reconstructive methods using free iliac bone, external tabula, or sandwich plasties are only a few examples of the common surgical treatment modalities. Doing without bone grafts, alveolar ridge augmentation by means of distraction osteogenesis might become a value method to improve the denture-bearing area. A new distraction implant system is shown and its first clinical use reported. Two distraction implants were inserted after an anterior segmental osteotomy. The alveolar ridge was then elevated 1 mm each day until the required augmentation of about 8 mm was achieved. After a latency period for pre-ossification of the callus, the distraction implants were replaced by the endosseous implants. The implant system and the surgical technique are shown, and the results are discussed. We believe that the implant distraction procedure will make useful contribution to the management of masticatory rehabilitation.The masticatory rehabilitation of patients is dependent on the quality and volume of residual jaw bone. Loss of volume caused by tumor-related mandibular ridge resection or age-related atrophies may cause considerable problems. Reconstructive methods using free iliac bone, external tabula, or sandwich plasties are only a few examples of the common surgical treatment modalities. Doing without bone grafts, alveolar ridge augmentation by means of distraction osteogenesis might become a value method to improve the denture-bearing area. A new distraction implant system is shown and its first clinical use reported. Two distraction implants were inserted after an anterior segmental osteotomy. The alveolar ridge was then elevated 1 mm each day until the required augmentation of about 8 mm was achieved. After a latency period for pre-ossification of the callus, the distraction implants were replaced by the endosseous implants. The implant system and the surgical technique are shown, and the results are discussed. We believe that the implant distraction procedure will make useful contribution to the management of masticatory rehabilitation.

Secondary Mandibular Reconstruction After Oral Squamous Cell Carcinoma Resection: Clinical Reevaluation of Transport Disk Distraction Osteogenesis

Besides bone grafting, transport disk distraction osteogenesis (TDDO) is an alternative approach that can be used for the reconstruction of the mandibular arch after neoplastic surgery. Although several animal experiments are reporting about the applicability of this technique, little is known about its long-term success in human beings. In this study, we report about the successful treatment of patients with defects of their mandibular arch due to tumor resection by means of the external bifocal TDDO. A total of 7 patients (n = 3 with lateral, n = 4 with anterior defects) were followed up for a mean period of 56 months. Although neither adjuvant nor neoadjuvant chemotherapy negatively influenced callus formation, prereconstructive radiation with a dose of 51 Gy led to an insufficient callus formation. The reconstruction of anterior defects was unsatisfying because tensions from the soft tissue on the fragile and rubber-like callus negatively influenced the natural arch shaping. In these cases, additional surgery was often required. However, reconstruction of lateral defects of the mandibular arch was more successful and resulted in functional bone with good quality, in which dental implants could be inserted. The results of this study emphasize that TDDO by means of bifocal distraction provides functional bone comparable to residual bone. Lateral defects of mandibular arch can be better reconstructed, whereas anterior defects often require additional surgery.

Tight spatial and temporal control in dynamic basal to distal migration of epithelial inflammatory responses and infiltration of cytoprotective macrophages determine healing skin flap transplants in mice.

Objective:We aimed to elucidate to date unknown molecular patterns of dynamic inflammatory tissue responses during uncomplicated healing of caudally pedicled skin flap transplants in mice. Summary Background Data:Distal skin flap ischemic necrosis is a well-known complication in surgery. To improve ischemic conditions in impaired skin flaps, recent work attempted to increase insufficient vascularity by application of angiogenic growth factors or pluripotent cells. Wound inflammation is in the center of tissue repair, but its temporal and spatial regulation remains nearly unstudied in conditions of transplanted skin flap tissue. Methods:RNase protection assay, quantitative real-time polymerase chain reaction, immunohistochemistry, enzyme-linked immunosorbent assay (ELISA) and immunoblot techniques were used to determine expression and cellular localization of central inflammation-related chemokines, cytokines, enzymes and cell types upon skin flap transplantation. Results:We observed a marked keratinocyte-driven inflammation that moved from the caudal base to distal flap regions during healing. Keratinocytes of the skin flap epithelium expressed increasingly large amounts of chemokines (MIP-2, MCP-1) and cyclooxygenase (Cox)-2 particularly in distal portions of the transplant. The underlying wound bed did not appear to contribute essentially to the inflammatory response. Despite strong attracting chemokine signals, distal flap tissue was not infiltrated by excess numbers of neutrophils and macrophages. Moreover, infiltrating macrophages exhibited an anti-inflammatory phenotype characterized by the absence of NFκB activation and Cox-2 in the presence of a marked heme oxygenase (HO)-1 expression in surviving skin flap tissue. Conclusion:Survival of skin flap tissue might be determined by a cytoprotective type of wound macrophage in the presence of an intense epithelium-derived inflammation.

Growth of the orbit after frontoorbital advancement using nonrigid suture vs rigid plate fixation technique

PURPOSE To demonstrate whether a measurable difference occurs on the growth of the orbit when using 2 forms of stabilization of the supra-orbital rim after upper orbital osteotomy in children with craniosynostosis. The 2 methods of fixation include sutures providing nonrigid fixation and titanium or resorbable osteosynthesis plates. PATIENTS AND METHODS In this prospective randomized study, the influence of the mentioned fixation materials was analyzed in a tertiary care center (university hospital). Sixteen consecutive children with craniosynostoses (trigonocephaly, brachycephaly, plagiocephaly) were included. All patients underwent bilateral frontoorbital advancement surgery. In 8 patients each, the fixation of the mobilized and reshaped supraorbital rim was carried out using either miniplates or sutures, resulting in a rigid or nonrigid fixation. By means of computed tomography scans taken preoperatively (mean age, 8months) and postoperatively (mean age, 6.5years), the development of the orbit was measured using the anterior interorbital distance, lateral orbital distance, medial orbital-wall length, lateral orbital-wall length, and medial orbital-wall protrusion. The results were compared to norm values and statistically evaluated. RESULT In all patients, a long-term improvement of the orbit was achieved with absolute distances staying below norm values. The choice of the fixation material was of minor importance. CONCLUSION Sutures providing nonrigid fixation of bone flaps seem to be feasible in reaching the aims of surgery in craniosynostotic children.

The importance of the primary reconstruction of the traumatized anterior maxillary sinus wall.

This study evaluates the importance of specific posttraumatic reconstruction of the fractured anterior sinus wall. Several methods of different complexity of reconstruction are being compared by means of radiologic, rhinoscopic, and clinical data. Four groups of a total of 207 patients (age, 18-73 years; follow-up average, 4.2 years) with midfacial fractures, divided by operation technique and year, were evaluated. Control groups 1 to 3 received standard procedures without special regard on the reconstruction of the anterior sinus wall; the study group received specific reconstruction. The study group 4 showed a lower complication rate in nearly all measured parameters in comparison to groups 1 and 2. Study group 4 had the smallest incidences of posttraumatic sequelae in radiologic examinations; the clinical outcome was even to group 3. During open reduction and fixation procedures of midfacial fractures, attention should be given to the reconstruction of the anterior sinus wall to avoid postoperative discomfort.

Quality of implant anchored craniofacial and intraoral prostheses: patient's evaluation.

BackgroundsBone-anchored prostheses have become a major issue in the rehabilitation of patients with facial defects. The objective of this study was to analyze how patients perceived the quality of implant-retained orbit, ear, nose, maxilla, or partial face prosthesis. MethodsThe patients’ satisfaction from implant-retained prostheses usage was evaluated by a group of 30 patients with various facial defects. The survey referred exclusively to oncologic patients. Surveyors were classified basing on their age, sex, and defect localization, and their satisfaction was assessed by standardized questionnaire with 6-grade scale. ResultsOverall, acknowledging some weaknesses, such as reduced condition of surrounding soft tissue and necessity to enhance hygienic care, most of the patients assessed their prostheses as “good” emphasizing excellent mechanical retention and high wearing comfort. More detailed analysis revealed itemized outcome: (i) auricular prosthesis was indicated as the most comfortable solution by the patients; (ii) women and patients older than 55 years were more satisfied with the treatment results than men and patients younger than 55 years; and (iii) implant-retained prostheses were generally rated better than conventional adhesive–retained solutions. ConclusionsThe results of the study proved that generally implants improve the satisfaction of patients with craniofacial prostheses. However, the actual level of satisfaction depends, to a large extent, on the defect’s localization, sex, and age of the patient.

CT-gestützte Volumetrie und Densitometrie von distraktionsosteogenetisch verlängerten Unterkieferarealen

Gradual callus distraction in the correction of hypoplastic areas in the viscerocranial skeleton is an established method due to its efficacy. Whereas functional and esthetical improvements can be seen easily, it is impossible to get the increase of the bony mass right using the distractor scale or by clinical investigation. Only in animal studies can volumetric and densitometric measurements be done directly. By permission of the local ethics commission, in a clinical study, CT data of 24 children (12 unilateral and bilateral hypoplasias each) taken before and after mandibular distraction osteogenesis were used to get information on the amount of created bone and the grade of ossification of the callus at the time of the distractor removal. The CT data were prepared for computer evaluation using software which had been especially developed for this investigation. The quality of the investigation was influenced by disturbed data acquisition (insufficient sedation, Gantry deviation, different axial cuts). Therefore, the estimation of the real increase of bone was not possible, but all in all an increase of the volume could be seen. Using a grey scale analysis, the grade of new bone ossification was over 90% at the time of distractor removal. In our opinion, these results argue against the use of CT scans for the validation of a mandibular distraction. The estimation of the volume is very imprecise, the grade of ossification of the new bone very constant.Die schrittweise Kallusdistraktion zur Korrektur hypoplastischer Knochenareale ist im Bereich des viszerokranialen Skeletts als effiziente Methode etabliert. Während die funktionellen und auch ästhetischen Verbesserungen bei den Patienten leicht registriert werden können, gelingt eine verlässliche Aussage über den tatsächlichen Knochenzuwachs anhand von klinischem Befund und Distraktorskala kaum. Direkte volumetrische und densitometrische Untersuchungen sind nur im Tierversuch möglich, für die klinische Anwendung müssen jedoch andere Verfahren herangezogen werden. Wir haben daher ¶in einer von der örtlichen Ethikkomission genehmigten klinischen Studie bei ¶24 Kindern (je 12 uni- und bilaterale Distraktionen; Durchschnittsalter 8,2 Jahre), die wegen einer mandibulären Mikrognathie mit Hilfe der Distraktionsosteogenese behandelt wurden, versucht, anhand von vor und nach erfolgter Distraktion erstellten Computertomogrammen sowohl das Volumen des neu geschaffenen Knochens als auch den Grad seiner Ossifikation zum Zeitpunkt der Distraktorentfernung zu ermitteln. Nach manueller Vorbereitung der CT-Sequenzen wurden die CT-Daten in einem speziell für diese Untersuchung erstellten Computerprogramm ausgewertet. Aufgrund von Störeinflüssen bei nicht protokollgerechter Datenakquisition (Schichtdicke, Gantry, Sedierung des Patienten) und dadurch verursachten erheblichen interindividuellen Schwankungen sind bezüglich des tatsächlichen Volumenzuwachses nur vereinzelt realistische Angaben möglich, insgesamt ist aber ein Volumenzuwachs belegt. Die Bestimmung des Ossifikationsgrads über eine Grauwertanalyse zeigte generell eine Ossifikation des neuen Knochens > 90% zum Zeitpunkt der Distraktorentfernung. Die hier gewonnenen Ergebnisse sprechen gegen den Einsatz und die Notwendigkeit der CT-gestützten Validierung einer mandibulären Distraktion: Die Erfassung des Volumens ist zu unsicher, der Ossifikationsgrad des neuen Knochens interindividuell sehr konstant. Gradual callus distraction in the correction of hypoplastic areas in the viscerocranial skeleton is an established method due to its efficacy. Whereas functional and esthetical improvements can be seen easily, it is impossible to get the increase of the bony mass right using the distractor scale or by clinical investigation. Only in animal studies can volumetric and densitometric measurements be done directly. By permission of the local ethics commission, in a clinical study, CT data of 24 children (12 unilateral and bilateral hypoplasias each) taken before and after mandibular distraction osteogenesis were used to get information on the amount of created bone and the grade of ossification of the callus at the time of the distractor removal. The CT data were prepared for computer evaluation using software which had been especially developed for this investigation. The quality of the investigation was influenced by disturbed data acquisition (insufficient sedation, Gantry deviation, different axial cuts). Therefore, the estimation of the real increase of bone was not possible, but all in all an increase of the volume could be seen. Using a grey scale analysis, the grade of new bone ossification was over 90% at the time of distractor removal. In our opinion, these results argue against the use of CT scans for the validation of a mandibular distraction. The estimation of the volume is very imprecise, the grade of ossification of the new bone very constant.