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PubMed1996

A novel model system for the study of experimental guided bone formation in humans.

The aim of the present experiment was to test a novel model system, designed to obtain human specimens of regenerated and also newly regenerated jaw bone, for the study of the biological events under a variety of conditions. Following information and disclosure of possible risks associated with a minor oral surgical procedure, 9 systemically healthy subjects (5 men, 4 women, mean age 31.7 years) signed consent forms and volunteered to participate in this study. Hollow test cylinders with an outer diameter of 3.5 mm, an inner diameter of 2.5 mm, and 4 mm in height were used. They were manufactured from commercially pure titanium and exhibited a highly polished inner surface and a titanium plasma sprayed outer rough surface. A mucoperiosteal flap was raised in the retromolar area of the mandible corresponding to standard retrained third molar surgery. Following flap reflection a standardized hole was drilled through the cortical bone into the bone marrow using round burs. The congruent test cylinders were firmly placed into the prepared bony bed yielding primary stability. One-and-a-half to 2 mm of the test device were submerged below the level of the surrounding bone, while the remainder surpassed the level of the bone surface. The bone-facing end of the cylinder was left open, while the coronal soft tissue facing end was closed by an ePTFE-membrane. The flap was sutured to obtain primary wound closure. In order to prevent infection, penicillin was prescribed systemically and oral rinses of chlorhexidine were administered. After 2, 7, and 12 weeks one test device including the regenerated tissue was surgically harvested, while after 16, 24 and 36 weeks respectively, 2 devices were harvested and processed for soft or hard tissue histology or histochemistry. The two surgical procedures and the presence of the test cylinders during the time of healing were well tolerated by the volunteers. In all 9 subjects generated tissue could successfully be harvested. The tissue generated after 2 and 7 weeks presented with a cylindrical shape, whereas the specimens harvested at 12 weeks and thereafter resembled the form of an hourglass. Specimens of 12 weeks and less regeneration time were almost entirely comprised of soft tissue, while specimens with regeneration time of 4 months and more were composed of both soft and increasing amounts of mineralized tissue. It is concluded that the presented model system is suitable to study temporal dynamics and tissue physiology of bone regeneration in humans with minimal risk for complications or adverse effects to the volunteers.

Adult↗
PubMed1975

New concept of morphogenesis of clefts in the lip, alveolus, and palate.

The morphogenesis of clefts in the lip, alveolus, and palate is a process of both functional and formative adaptation of the affected mouth cavity to the disturbance which the cleft would represent in "pumping" the amniotic fluid. Only a normally developed portal venous system of the foetus, which is a continuation of the digestive canal through the liver, ensures efficient per-oral nutrition after birth. According to the findings known to date, the foetus feeds by "pumping" the amniotic fluid as early as the end of the third month of pregnancy. The amniotic fluid and nutritive substances contained in the fluid, which the foetus receives from the mother through the umbilical vein, are for the greatest part discharged through the foetus's skin. The morphogenesis of clefts proves the formative power of the tongue and its importance in the development of the mouth cavity as well as the ability of the normal growth response of the tissues around the cleft.

Alveolar Process↗
PubMed1998

Reduction of implant loading with therapeutic biomechanics.

All physiologic biomechanical processes are interrelated and, therefore, reactive, which produces an accumulative effect that can cause implant overload. A new approach called "therapeutic biomechanics" suggests using corrective procedures to reduce implant loading. The head of the implant is positioned as close to the midline of the restoration as possible. Implant inclination may be required, but it produces less torque (moment) than horizontal implant offset. Posterior cross occlusion should be used where possible to decrease horizontal implant offset. Angulated, or reangulated abutments provide access or parallelism as needed. The posterior cusp inclination should be markedly reduced. When a vertical overlap is present anteriorly, a horizontal stop on the maxillary lingual surface redirects harmful lateral force to be vertical toward the implant and supporting bone. Because of physiologic variability, creating a modified centric occlusion that contains a 1.5-mm fossa will produce vertical resultant force within this range of motion rather than lateral force.

Alveolar Bone Loss↗
PubMed1997

Healing of intrabony defects and its relationship to root canal therapy. A histologic and histometric study in dogs.

The purpose of this study was to evaluate the importance of root canal therapy in the healing process of severe intrabony defects. Four beagle dogs were used and 32 interproximal intrabony defects, up to the apical third, were created. Wire ligatures were placed into these defects for plaque accumulation. Three weeks later, the ligatures were removed and 4 different treatment modalities were employed: group 1) scaling and root planing (SRP); group 2) modified Widman flap (MWF); group 3) modified Widman flap and root canal therapy performed at the same time (RCT/MWF); and group 4) modified Widman flap and root canal therapy performed 3 weeks after the surgical procedure (MWF + RCT). Postoperative oral hygiene was obtained by spraying a 0.12% chlorhexidine solution 3 times a week. The animals were sacrificed 7 weeks after treatment. Blocks were obtained and processed for routine histology. Results were expressed as a percentage of the total defect length (TDL). No differences were observed when SRP was compared to MWF. New bone formation (BF) presented better results for SRP (43.4%) and MWF (53.4%) when compared to RCT/MWF (15.5%). New cementum formation (CF) presented better results for SRP (59.8%) and MWF (64.6%) when compared to RCT/MWF (19.3%) and MWF + RCT (31.5%). Connective tissue repair (CTR) presented better results for SRP (72.4%) and MWF (74.2%) when compared to RCT/MWF (47.5%) and MWF + RCT (44.4%). Results were statistically significant at the level of 0.05. Within the limits of this study, it was concluded that root canal therapy performed simultaneously or 3 weeks after surgery modified the healing of intrabony defects, impairing new bone formation, new cementum formation and new attachment.

Alveolar Bone Loss↗
PubMed2003

Coronally positioned flap with or without enamel matrix protein derivative for the treatment of gingival recessions.

PURPOSE: To evaluate, histometrically, the healing of gingival recessions treated by coronally positioned flaps associated with enamel matrix protein derivative (EMD-Group) and to compare it to that obtained with coronally positioned flaps alone (CPF-Group). METHODS: Five mongrel dogs were used. Gingival recessions were surgically created on the buccal aspect of the upper cuspids. The defects (5 x 7 mm) were exposed to plaque accumulation for 3 months. After a preparation period, the contralateral defects were randomly assigned to each group. After 3 months of healing, the dogs were sacrificed and the blocks were processed. The histometric parameters evaluated included: gingival recession, length of epithelium, new connective tissue attachment and new bone. RESULTS: The gingival recession was -0.1 +/- 0.2 mm for the EMD-Group and -0.8 +/- 1.3 mm for the CPF-Group (P = 0.17). The extension of the epithelium was 1.2 +/- 1.0 mm for the EMD-Group and 1.3 +/- 0.7 mm for the CPF-Group (P = 0.89). The new connective tissue attachment was 4.8 +/- 0.7 in the EMD-Group and 4.0 +/- 1.4 in the CPF-Group (P = 0.22). The new bone was 0.1 +/- 1.8 mm and -0.5 +/- 1.4 mm in the EMD-Group and CPF-Group, respectively (P = 0.50). Histologically, the defect coverage observed was 98.2% for the EMD-Group and 85.8% for the CPF-Group.

Acid Etching, Dental↗
PubMed2006

Bone regeneration in dehiscence-type defects at chemically modified (SLActive) and conventional SLA titanium implants: a pilot study in dogs.

OBJECTIVES: The aim of the present study was to evaluate bone regeneration in dehiscence-type defects at titanium implants with chemically modified (mod) and conventional sand-blasted/acid-etched (SLA) surfaces. MATERIAL AND METHODS: Standardized buccal dehiscence defects (height: 3 mm, width: 3 mm) were surgically created following implant site preparation in both the upper and lower jaws of four beagle dogs. modSLA and SLA implants were inserted bilaterally according to a split-mouth design. The animals were sacrificed after 2 and 12 weeks (n=2 animals each). Dissected blocks were processed for histomorphometrical analysis: defect length, new bone height (NBH), percent linear fill (PLF), percent of bone-to-implant contact (BIC-D) and area of new bone fill (BF). RESULTS: Wound healing at SLA implants was predominantly characterized by the formation of a dense connective tissue at 2 and 12 weeks, without significant increases in mean NBH, PLF, BIC-D or BF values. In contrast, modSLA implants exhibited a complete defect fill at 12 weeks following implant placement. In particular, histomorphometrical analysis revealed the following mean values at 12 weeks: NBH (3.2+/-0.3 mm), PLF (98%), BIC-D (82%) and BF (2.3+/-0.4 mm(2)). CONCLUSION: Within the limits of the present study, it was concluded that modSLA titanium surfaces may promote bone regeneration in acute-type buccal dehiscence defects at submerged implants.

Acid Etching, Dental↗
PubMed1989

The effect of cortisone on the eruption rate of root-resected incisors in the rat.

It is generally thought that the periodontal ligament plays a key--perhaps even exclusive--role in tooth eruption. The present study was designed to test the hypothesis that the fundus also may contribute to the process. To this end the effect of cortisone on the eruption rate of root-resected mandibular incisors was examined in male albino rats. Half of the animals received daily injections of cortisone; the other half were given normal saline. Impeded and unimpeded eruption rates were measured at 3-day intervals and tested for between- and among-means differences by repeated-measures analysis of variance (ANOVA). In contrast to the acceleration commonly seen in intact incisors, cortisone produced no change in the eruption rate of root-resected incisors. It was concluded therefore that the accelerative effect of cortisone is mediated by the fundus, rather than the periodontal ligament. Further, it is hypothesized that early eruption is controlled by cellular proliferation within the fundus; however, once the tooth enters the oral cavity and becomes functional, the periodontal ligament matures and becomes the dominant factor in subsequent eruption.

Alveolar Process↗
PubMed1988

New attachment achieved by guided tissue regeneration in beagle dogs.

This study tested the effects of using a Gore-Tex periodontal material on new connective tissue attachment in beagle dogs with natural periodontitis. Seven female beagle dogs with advanced periodontitis were selected and given thorough root debridement. Under general anesthesia four weeks later, mucoperiosteal flaps were raised involving all mandibular premolars and first molars. Gore-Tex periodontal material was adapted to all premolars, and the flaps were sutured tightly, keeping the material covered. The first molars acted as controls, receiving only surgery. Some material was removed in one month, while other materials were removed eight to 10 weeks after surgery. All dogs were sacrificed at three months. After processing, descriptive histology and histometrics were carried out, evaluating new connective tissue attachment, bone response and epithelial downgrowth. Results were statistically analyzed, using paired t tests. They showed new connective tissue attachment with cementum deposition in areas where the material was used. Also, the epithelial downgrowth was reduced in these areas. In the controls, minimal connective tissue attachment was found, with the area healing by a long junctional epithelium. Statistical analysis showed significant differences (P less than 0.05) favoring experimental areas both in the increase of new connective tissue attachment and in the decrease of epithelial downgrowth. No differences were found between areas where the material was removed in one month or left longer in place. No difference in bone response was found. Gore-Tex material was effective in blocking gingival epithelial downgrowth and connective tissue proliferation, promoting new attachment according to the principle of "guided tissue regeneration."

Alveolar Process↗
PubMedDate not supplied

Bone and soft tissue integration to titanium implants with different surface topography: an experimental study in the dog.

The aim of the present experiment was to study the peri-implant soft and hard tissues formed at titanium implants with 2 different surface configurations and to give a topographic description of the surfaces examined. In 5 beagle dogs, the mandibular premolars were extracted. Three months later, 4 self-tapping standard implants (SI) and 4 Osseotite implants (OI) of the 3i Implant System were placed. The marginal 3 mm of the OI is turned, while the remaining part has an acid-etched surface structure. Abutments were connected after 3 months. A plaque control period was initiated, and after 6 months block biopsies were obtained. From each animal 2 units of each implant type were processed and embedded in EPON. The remaining biopsies were processed for ground sectioning. The histometric measurements performed on the EPON sections revealed that the peri-implant soft tissues and the marginal level of bone-to-implant contact were similar for SI and OI sites. In the ground sections, bone-to-implant contact (BIC%) and bone density assessments were made in 2 different zones. Zone I represented the contact area measured from the marginal level of bone-to-implant contact (B) to a position 4 mm above the apex of the implant, and zone II represented the apical 4 mm of the implant. For the SI sites, the BIC% was 56.1% in zone II and 58.1% in zones I + II. The corresponding figures for the 01 sites were 76.7% and 72.0%. The BIC% was significantly larger at OI than at SI sites. Bone density values were similar at the SI and OI sites.

Acid Etching, Dental↗
PubMed2001

Brown tumor of the maxilla associated with primary hyperparathyroidism.

Brown tumors represent the terminal stage of the remodeling processes during primary or secondary hyperparathyroidism. During the last three decades primary hyperparathyroidism has been recognized much more commonly and the increase has generally been attributed to the routine determination of calcium by new automated methods and the advent of new and more objective parathyroid hormone radioimmunoassay techniques. Early diagnosis and successful treatment of the disease have made clinical evidence of bone disease uncommon. While, the mandible is the most frequently involved bone in the head and neck region, maxillary involvement is extremely rare. A case of brown tumor on the maxilla associated with primary hyperparathyroidism is reported. This patient presented multiple skeletal lesions, which are uncommonly seen nowadays. The diagnosis was suggested by the clinical history and confirmed by biochemical, radiological and histopathological determinations. Excision of a parathyroid adenoma normalized the metabolic status. Excision of the maxillary mass led both histopathological confirmation of the disease and early masticator rehabilitation.

Adenoma↗
PubMed2001

Effects of carrier release kinetics on bone morphogenetic protein-2-induced periodontal regeneration in vivo.

BACKGROUND: Bone morphogenetic proteins (BMPs) have shown considerable promise as a therapeutic agent to enhance periodontal regeneration although the optimal characteristics of a suitable release system are not known. AIM: The aim of this study was to compare the effects of slow and fast degrading gelatin carriers on BMP-2-induced periodontal healing. METHOD: Recombinant human bone morphogenetic protein-2 (rhBMP-2) was incorporated into gelatin and subsequently differentially cross-linked to produce slow and fast release carrier systems. Release kinetics were confirmed in vitro, by measuring release of 125I-growth hormone from similar gelatin plugs. Effects of BMP were evaluated in surgically created rat periodontal fenestration defects which were processed for histology 10 days post-operatively. The rats were divided into 4 groups and the control defects were treated with either slow or fast degrading gelatin (CONs or CONf respectively), whilst test groups were treated with 1.25 microg rhBMP-2 in the slow or fast degrading gelatin (BMPs or BMPf respectively). RESULTS: BMPf greatly increased bone formation compared with the control (CONf) (1.67 +/- 0.65 versus 0.34 +/- 0.11 x 10(-4) m2), but no significant differences were observed with BMPs and CONs. In contrast, new cementum formation was significantly greater in the BMPs group compared with all other groups (p<0.05). CONCLUSION: Release kinetics of BMP may have important effects on the outcome of BMP-induced periodontal regeneration. New bone formation may be affected by rapid-release kinetics although further investigation is necessary to confirm this. In contrast, new cementum formation is promoted by slow release of BMP.

Alveolar Bone Loss↗
PubMed1991

Doxycycline-tricalcium phosphate composite graft facilitates osseous healing in advanced periodontal furcation defects.

The purpose of this study was to compare the effectiveness of a tricalcium phosphate, plaster of paris, and doxycycline composite graft to surgical debridement alone in the treatment of Class II and Class III furcation defects. Fifteen patients with adult periodontitis and at least two mandibular molars with Class II or III furcation defects were selected. A total of 40 sites were treated: 26 were Class II defects and 14 were Class III. Following initial therapy one site was randomly selected to receive the composite graft while the remaining site served as the surgically debrided control. Osseous healing was evaluated by direct measurements from an acrylic stent at the time of graft surgery and at the 6-month reentry. Following surgery each patient was placed on doxycycline 100mg/day for 10 days. The absence of clinical inflammation and infection during the healing process provided additional substantiation of the biocompatibility of the grafting materials. Results after 6 months indicated that sites treated with the composite graft had improved defect fill, defect resolution, probing depths, and clinical attachment levels when compared to the surgically debrided controls. Defect fill was 3.7 times greater in grafted sites and these sites were 4.0 times more likely to have 50% or greater defect fill. The effect of grafting was more pronounced in Class III defects where horizontal defect fill and gain of clinical attachment was achieved only in grafted sites. The plaster of paris functioned well as a binder, preventing particle scatter and facilitating graft retention. Additionally the plaster served as a vehicle to carry and retain the doxycycline at the treated site. These short-term results point to the potential of a composite graft containing tricalcium phosphate, plaster of paris, and doxycycline in promoting healing of furcation lesions.

Adult↗
PubMed2006

Effect of early membrane removal on regeneration of Class II furcation defects in dogs.

BACKGROUND: This study evaluated the influence of early removal of an expanded polytetrafluoroethylene (ePTFE) membrane on periodontal regeneration. METHODS: The third and fourth mandibular bicuspids of six healthy mongrel dogs were used. Class II furcation lesions were surgically created making lesions chronic for 21 days. Full flaps were elevated, and ePTFE membranes were adapted over the defects. The membranes were removed at 2 weeks on the experimental sides (test group [TGr]) and at 4 weeks on the control side (control group [CGr]). The dogs were sacrificed 12 weeks following placement of the membranes, and the teeth were histologically processed. Area measurements of new tissue (NT), epithelium (EP), connective tissue (CT), and new bone (NB) and linear measurements of bone height (BH) and new cementum (NC) were made. Wilcoxon signed rank test (P <0.05; N = 6) was carried out to determine differences between groups. RESULTS: The area measurements (in mm2) for TGr and CGr, respectively, were as follows: 14.32 +/- 4.01 and 12.46 +/- 3.54 (NT); 0.04 +/- 0.09 and 0.01 +/- 0.04 (EP); 2.31 +/- 2.60 and 1.91 +/- 2.96 (CT); and 9.56 +/- 3.77 and 8.79 +/- 2.99 (NB). The results of the linear measurements (in mm) for TGr and CGr, respectively, were as follows: 3.85 +/- 1.21 and 4.03 +/- 0.94 (BH) and 10.91 +/- 1.72 and 10.59 +/- 1.80 (NC). There were no statistically significant differences between TGr and CGr for any measurement. CONCLUSION: The early removal of ePTFE membranes in Class II furcation defects in dogs did not affect periodontal regeneration.

Alveolar Process↗
PubMed1999

Bone classification: clinical-histomorphometric comparison.

This study was aimed to correlate the hand clinical assessment of the bone quality to the histologic structure quantified by histomorphometric evaluation of bone density. Small bone biopsies were harvested in 56 patients during oral implant surgery, and were utilized for histomorphometric evaluation. The bone scoring was recorded during drilling of the implant bed, based on the hand-felt perception of the drilling resistance. The bone biopsies were then processed to obtain thin ground sections. The results of histomorphometric analysis were expressed as percentage of bony trabeculae over the total biopsy area, and the Spearman's rank correlation test, was applied to calculate the statistical differences of the clinically assessed classes of bone density and linear regression was calculated. Samples from the D1 showed a mean histomorphometric density of 76.54% +/- 16.19. Samples from D2 showed a mean value of 66.78% +/- 15.82. D3 specimens had a mean histomorphometric density scoring 59.61% +/- 19.55%. D4 samples had a mean value of 28.28% +/- 12.02. The interclass correlation analysis of the variance, showed that the clinically assessed classes D1 (P = 0.01) and D4 (P = 0.0006) were significantly different from the population. On the other hand, the classes D2 (P = 0.6) and D3 (P = 0.4) were not significantly different. This study demonstrated that hand feeling allows to distinguish, with statistically significant confidence, D1 and D4 bone, but failed to distinguish between the intermediate classes of bone quality.

Alveolar Process↗
PubMedDate not supplied

Load transfer by an implant in a sinus-grafted maxillary model.

PURPOSE: This in vitro study determined the stress distribution around an implant placed in a posterior edentulous maxillary model with simulated sinus grafts that had different degrees of stiffness. MATERIALS AND METHODS: The composite photoelastic model with a standard threaded implant consisted of simulated crestal cortical, cancellous, sinus cortical, and grafted bone. The graft maturation process and inherent graft quality were represented in the model by varying the stiffness of the graft. Prior to placement of the simulated graft, axial and inclined loads were applied to the implant The stresses that developed in the supporting structures were analyzed photoelastically. The graft was then placed and the testing procedure was repeated over 4 consecutive days, during which time the simulated graft stiffened. RESULTS: The stress analysis indicated that before placement of the simulated graft, loading on the implant transferred the highest stresses to cortical bone. The presence of the simulated graft transferred stress from the native bone simulants to the simulated grafted bone. DISCUSSION: As the stiffness of the graft increased, a more equitable stress distribution was observed in the multilayer bone surrounding the implant. CONCLUSION: Loading of an implant in a less stiff grafted sinus could lead to overloading of the native bone as well as the maturing grafted bone.

Alveolar Process↗
PubMed1999

Peri-implant tissues at submerged and non-submerged titanium implants.

The present experiment was performed to study the peri-implant tissue response to non-submerged (1-stage) and initially submerged (2-stage) implant installation procedures. 6 beagle dogs were used. All mandibular premolars and the 1st, 2nd and 3rd maxillary premolars were extracted. After 3 months of healing, 3 fixtures of the Astra Tech System were installed and submerged in the right (or the left) edentulous, premolar region in each of the 6 dogs. Radiographs were obtained immediately after fixture installation. In the radiographs, the distance between the abutment-fixture junction and the most "coronal" bone in contact with the implant surface was determined. 3 months later, abutments were connected to the initially submerged fixtures and another 3 fixtures of the same system were installed in the contralateral, edentulous premolar region. Abutments were, however, immediately connected to the newly-installed fixtures (non-submerged side; test side). The mucosal flaps were replaced, adjusted and sutured in such a way that the coronal portion of the abutments remained exposed in the oral cavity. A new set of radiographs were obtained from all 6 implant sites in each animal. A period of plaque control was initiated. Clinical examinations were performed and radiographs obtained from all implant sites after another 3 months and at the termination of the experiment. 9 months after the 1st fixture installation procedure, the animals were sacrificed, the mandibles were removed, and each implant region dissected. The most mesially-located implant sites were processed for ground sectioning. The remaining biopsies were processed and embedded in EPON. The histometric analysis included assessment of the vertical dimension of the marginal soft and mineralized peri-implant tissues. The ground sections were used for measurements describing (i) "bone to implant contact" and (ii) "bone density". It was observed that the mucosa and bone tissue that formed at implants placed in a non-submerged or a submerged procedure had many features in common. Thus, figures describing (i) the height of the mucosa, (ii) the length of the junctional epithelium and the height and quality of the zone of "connective tissue integration", (iii) the % of bone to implant contact as well as (iv) the density of the peri-implant bone, were similar in the submerged and the non-submerged groups. It is therefore suggested that a non-submerged (1-stage) installation technique may provide conditions for tissue integration that are similar to those obtained using a submerged (2-stage) approach.

Alveolar Process↗
PubMed2006

Bone microvascular pattern around loaded dental implants in a canine model.

The vascularity of the implant bed is a very important parameter in both bone formation and maintenance after dental implants insertion. The relationship between bone and vessels network organization is still unknown. The aim of this study was to investigate the three-dimensional bone vascular canals of the peri-implant bone after loading. A total of ten implants with sandblasted and acid-etched surface were placed in the mandible of a beagle dog. Three months later, the implants were connected and loaded. The dog was killed after 12 months. The specimens were embedded and processed for scanning electron microscopy (SEM) analysis. After a 1-year loading period, a very intricate vessel network could be seen around the implants. The vessels, with neighbouring soft tissues, were round in shape and showed a lot of anastomoses with a mesh-like appearance. They ran circularly around the dental implant. In the bone, the majority of the vessels appeared to ran parallel to the mandibular canal. After a 1-year loading period, the peri-implant bone vasculature looked like a mesh that surrounded the implants. Nevertheless, the presence of many thick vessels inside the peri-implant crestal bone indicates a high metabolic need and also a different bone organization, as no osteons were noted. The crater-like bone loss around the marginal part of the implant could be related to the microvasculature "strain". A high strain level could continuously activate the osteocyte-vessel syncytium, producing a net bone loss.

Alveolar Bone Loss↗
PubMed1991

Data-objective diagnosis of infant cleft lip, alveolus, and palate. Morphologic data guiding understanding and treatment concepts.

Maxillary plaster models of untreated infants with various cleft lip and palate forms have been studied under the Reflex Microscope. From the three- dimensional data processed by a PC, the specific dimensions of various cleft forms can be determined. Unexpected findings are that skeletal maxillary changes are present in infant velar clefts. The mid-sagittal maxillary length in particular becomes shorter with more severe clefting of the bony palate. From the morphologic point of view, Robin's sequence does not represent a specific entity, but usually a severe cleft of the hard palate. Unilateral clefts of lip, alveolus, and palate with a partial cleft lip reveal worse malformations than complete unilateral clefts. The morphologic changes recorded can be explained by a varying degree of lingual malposition. This reveals that displacements and malformations of infant cleft lip and palate are in fact secondary in nature. In correcting these secondary surface manifestations as soon as indicated by physiologic criteria one could hope for early normalization of sensation, perception, and function. Three-dimensional high-precision measurements are crucial for data-objective diagnoses, timing of therapy, choice of treatment, and in later evaluation of the results.

Alveolar Process↗