Anterior Segmental Distraction for a Class III Maxillary Prosthetic Defect in a Cleft Palate Patient

Prosthetic management of partially dentate patients with anterior maxillary defects when there is a full complement of lower teeth is challenging. Restoration is especially difficult when there is lack of upper lip support in a skeletal Class III individual. This clinical situation obligates the patient to a denture flange filling the vestibule to give support to the upper lip. Construction of the prosthesis can be even more of a challenge when there is scarring in the anterior vestibule. Patients who have had repair of a bilateral cleft lip and palate and have lost their anterior teeth frequently have this clinical situation. When a removable prosthesis is present, the fulcrum effect on abutment teeth from the prosthesis is detrimental to the long-term periodontal health of these teeth. Repetitive trauma to the edentulous segment from the cantilevered prosthesis results in the loss of the anterior alveolar ridge. Implants have radically changed the management of edentulous and partially edentulous patients by giving support to remaining alveolar bone and reducing the fulcrum effect on the abutment teeth.1–3 However, without adequate bony support of the upper lip, a denture flange is still necessary to achieve the normal projection of the lips.

Restoration of the horizontal deficient maxilla either through orthognathic or distraction techniques are well known.4,5 The majority of the published papers regarding advancement of the deficient maxilla are on patients with complete or near complete dentition.6,7 Patients with cleft lip and palate are a special group who often present with maxillary hypoplasia and may have a compromised dentition. Hierl and Hemprich8 presented their results with a patient who had a severely compromised remaining dentition with Le Fort I osteotomy with distraction via a halo external distractor. Jenson et al9 presented a case of internal distraction of an edentulous atrophic maxilla followed by the placement of osseointegrated implants. Segmental distraction of the anterior maxilla is also well known.8–10 Sándor et al showed the use of segmental distraction in a cleft lip and palate patient.11 Likewise, Karakasis and Hadjipetrou presented a case of segmental maxillary distraction in a cleft lip and palate patient.12 In both of these cases the patients had a near full complement of teeth and were done in conjunction with orthodontic therapy. In this article we will present the use of anterior segmental distraction in a partially edentulous adult cleft lip and palate patient who was missing his anterior teeth. This caused retraction of his lip when his prosthesis was removed. Following anterior segmental distraction, the fullness of his upper lip was restored. Implants were placed and he was able to have a fixed prosthesis giving both esthetic and functional result. The surgical prosthetic planning of the primary vector for the segmental distraction allowed placement of the implants in an ideal position and support of the upper lip without a labial flange.

A 32-year-old man with a history of bilateral cleft lip and palate repaired with multiple surgeries presented with an initial complaint of increasing difficulties wearing and chewing with his maxillary removal prosthesis. Approximately 15 years earlier he had undergone a Le Fort I maxillary advancement and a bilateral sagittal split setback in combination with orthodontics to correct his malocclusion (Figure 1). Clinically, he had a Class I dental occlusion but was missing all of his anterior teeth from the right cuspid around to the left cuspid. His anterior vestibule was limited by scarring from the surgeries to close his lip and nasoalveolar clefts. When his removable prosthesis was not in place, he had no lip support and appeared to be deficient in his maxilla (Figure 2). During the clinical examination it was noted that he was velopharyngeal incompetent. The patient wanted fixed reconstruction with dental implants with the hope that the eventual prosthesis would not have a flange.

In consultation with a prosthodontist and the patient, it was decided to do an anterior segmental distraction between the first and second maxillary bicuspids. The position of the osteotomy would allow a large enough transport segment to move forward while leaving his posterior occlusion intact. An anterior segmental distraction would have little or no effect on his pharyngeal function and speech. In addition to the routine work-up that included radiographs, models, and photographs, a stereolithographic model was obtained (Figure 3). To achieve the patient's goal of a fixed restoration, an anterior/inferior vector was chosen to place the internal distractors to move the alveolar segment both anterior and inferior.

The surgical procedure was performed under general anesthesia. Because of his previous surgeries, an anterior pedicle was maintained to increase the vasculature to the segment. After a 4-day latency healing period, distraction was initiated at a rate of 1.05 mm/day (0.35 mm/turn performed by the patient 3 times/day), for a total of 11 days (Figure 4). At this point he had good projection of his lip in profile, and the anterior posterior and vertical deficiencies of his maxillary ridge had been corrected (Figure 5a,b). The right premolar was in good position but the left was in a crossbite. To facilitate his restorative care, it was extracted. After a 3-month healing/consolidation period, the distractors were removed.

Four months after his distraction, 6 dental implants were placed in the right second bicuspid position as well as in the central incisor, left lateral, cuspid, and first bicuspid regions. From mounted case a splint was constructed to facilitate placement of the implants in the ideal position. The implants were 4.1 × 12 mm ITI implants (Straumann, Basel, Switzerland) with 3-mm cover screws. Bone level implants were placed in the sites of teeth numbers of the maxillary centrals, the left lateral, and cuspid (Figure 6). Because of excess soft tissue generated from the distraction, 3 months after the placement of the implants he underwent a gingival contouring. At 6 months after placement of the implants he was restored.

The restoration was relatively straightforward. The final impressions were made with an open face custom tray. Both light body and medium body tray material (Extrude, Kerr Dental Corporation, Orange, CA) was used to obtain the impressions. Fabricated custom abutments and crowns were in place. Abutments were inserted and torque to 35 N was applied on all implants. Following adjustment of the occlusion, all crowns were cemented with glass ionomer cement (Ketac-Cem, 3M ESPE, Norristown, Pa) (Figure 7). Following the insertion of the prosthesis, the patient maintained the good projection of his upper lip achieved with the distraction (Figure 8a and b).

Management of the patient with cleft lip and palate with skeletal malocclusions has been a challenge for the dental profession for years. The patients often have missing teeth and misaligned segments, which present a challenge for orthodontic and prosthetic care. In addition, these patients may have velopharyngeal insufficiency, which may complicate surgical repositioning of the maxilla. Several recent papers have discussed segmental anterior maxillary distraction as a way to correct the anterior posterior maxillary discrepancy without affecting the velopharyngeal mechanism.11,12 The focus of much of the literature on distraction has been on correction of the dentoalveolar segments, not necessarily on prosthetic management. While not mutually exclusive, achieving the fullness of the upper lip by increasing the underlying bony support can allow fixed prosthesis vs a removable one. Our case was planned to increase the lip support to allow placement of the implants and a fixed prosthesis. The maxillary vestibule was scarred from the previous surgeries limiting the restorative options. The vector of distraction was both vertical and horizontal to correct the anterior-posterior deficiency and give more vertical height. This not only allowed an improved implant position, but it restored the anterior vestibule for the patient.

Anterior segmental maxillary distraction in a partially edentulous patient can greatly facilitate prosthetic management of these individuals. Our case illustrates the combined prosthetic and surgical planning to allow the placement of a fixed restoration.