Modulation of tooth regeneration through opposing responses to Wnt and BMP signals in teleosts.

Most vertebrate species undergo tooth replacement throughout adult life. This process is marked by the shedding of existing teeth and the regeneration of tooth organs. However, little is known about the genetic circuitry regulating tooth replacement. Here, we tested whether fish orthologs of genes known to regulate mammalian hair regeneration have effects on tooth replacement. Using two fish species that demonstrate distinct modes of tooth regeneration, threespine stickleback (Gasterosteus aculeatus) and zebrafish (Danio rerio), we found that transgenic overexpression of four different genes changed tooth replacement rates in the direction predicted by a hair regeneration model: Wnt10a and Grem2a increased tooth replacement rate, whereas Bmp6 and Dkk2 strongly inhibited tooth formation. Thus, similar to known roles in hair regeneration, Wnt and BMP signals promote and inhibit regeneration, respectively. Regulation of total tooth number was separable from regulation of replacement rates. RNA sequencing of stickleback dental tissue showed that Bmp6 overexpression resulted in an upregulation of Wnt inhibitors. Together, these data support a model in which different epithelial organs, such as teeth and hair, share genetic circuitry driving organ regeneration.

Squamates as a model to understand key dental features of vertebrates.

Thanks to their exceptional diversity, teeth are among the most distinctive features of vertebrates. Parameters such as tooth size, shape, number, identity, and implantation can have substantial implications for the ecology and certain social behaviors of toothed species. Despite decades of research primarily focused on mammalian dentition, particularly using the laboratory mouse model, squamate reptiles ("lizards" and snakes) offer a wide array of tooth types and dentition variations. This diversity, which includes differences in size, shape, function, and replacement capacity, provides invaluable opportunities for investigating these fundamental properties. The central bearded dragon (Pogona vitticeps), a popular pet species with well-established husbandry practices, is of particular interest. It features a broad spectrum of morphs and spontaneous mutants and exhibits a wide range of heterodont phenotypes, including variation in the size, shape, number, implantation, and renewal of teeth at both posterior and anterior positions. These characteristics position the species as a crucial model organism for developmental studies in tooth research and for gaining deeper insights into evolutionary patterns of vertebrate dentitions. In this article, we provide an overview of the current understanding of squamate dentition, its diversity, development, and replacement. Furthermore, we discuss the significant advantages offered by squamate species as model organisms for investigating the evolutionary and developmental aspects of vertebrate dentition.

The Effect of Preformed Anatomic Provisional Restorations on Peri-Implant Mucosal Dimensions with Immediate Tooth Replacement Therapy.

OBJECTIVE: Immediate Tooth Replacement Therapy (ITRT) has become popular due to its ability to reduce treatment time and provide immediate esthetic results. However, long-term challenges, such as mid-facial recession and labial bone resorption, have been reported. Anatomic temporary cylinders (ATC), which allow for efficient fabrication of provisional transitional restorations in the esthetic zone, were designed to mimic the natural emergence profile and guide mucosal tissue healing. This study examines the effect of ATCs on the fabrication of provisional restorations compared to conventional non-anatomic temporary cylinders (CTCs) in terms of peri-implant mucosal preservation and stability in patients undergoing ITRT using the dual-zone grafting technique. MATERIALS AND METHODS: Parameters evaluated were peri-implant mucosal tissue thickness (PIMTT), Pink Esthetic Score (PES), and radiographic outcomes, including labial plate dimension (LPD). RESULTS: The use of ATCs resulted in a statistically significant increase in PIMTT compared to CTCs, suggesting better preservation of peri-implant mucosal architecture. Additionally, the ATC group exhibited a positive change in LPD, although this difference was not clinically significant. CONCLUSIONS: The findings indicate that ATCs may offer advantages in maintaining peri-implant mucosal stability, contributing to the esthetic and functional outcomes of implant-supported restorations. Further long-term studies are needed to validate these preliminary results. CLINICAL SIGNIFICANCE: The use of anatomic temporary cylinders (ATC) in immediate tooth replacement therapy (ITRT) demonstrated improved peri-implant mucosal tissue thickness, suggesting enhanced maintenance of peri-implant mucosal architecture. This can contribute to healthier and more esthetic outcomes while potentially reducing the risk of complications such as mid-facial recession.

Over-eruption in marsupial carnivore teeth: compensation for a constraint.

Pronounced over-eruption of the canine teeth, causing the cervical enamel margin to extend beyond the alveolar bone and exposing the root, occurs with age and growth in Australian marsupial carnivores, much more than in eco-morphologically equivalent placental carnivores. Suppression of functional tooth replacement is characteristic of marsupials, where most placentals have the primitive diphyodont pattern of two generations of incisor, canine and premolar teeth. Canine and molar tooth dimensions of four species of marsupial carnivores (thylacine Thylacinus cynocephalus, Tasmanian devil Sarcophilus harrisii and two quolls Dasyurus spp.) and canine dimensions of seven eco-morphologically equivalent placental carnivore species were measured from museum specimens. Canine dimensions were measured in a time series on live wild-living individual devils and quolls. The canine teeth and to a lesser extent the molar teeth of marsupial carnivores continue to erupt through life, resulting in a net increase in tooth height and diameter, a phenomenon not evident in placental carnivores. Potential mechanisms causing over-eruption include tooth wear and gradual release of occlusal pressure as the individual grows. Over-eruption in marsupial carnivores may be a compensatory response for tooth size limits imposed by monophyodont tooth replacement, ensuring that animal's teeth are scaled to jaw size from juvenile to adulthood.

Palaeohistology reveals an unusual periodontium and tooth implantation in a filter-feeding pterodactyloid pterosaur, Pterodaustro guinazui, from the Lower Cretaceous of Argentina.

Pterosaurs are an extinct group of Mesozoic flying reptiles, which exhibited high diversity with regard to their dentition. Although morphological features of pterosaur dentition have been described in detail in several contributions, the histology of tooth and tooth attachment tissues (i.e. periodontium) has been scarcely analysed to date for this clade. Here we describe and interpret the microstructure of the tooth and periodontium attachment tissues of Pterodaustro guinazui, a filter-feeding pterodactyloid pterosaur from the Lower Cretaceous of Argentina. The histological analysis of the lower jaw and its filamentous teeth verifies that the geometry of the implantation corresponds to an aulacodont condition (i.e. teeth are set in a groove with no interdental separation). This pattern departs from that recorded in other archosaurs, being possibly also present in other, non-closely related, pterosaurs. Regarding tooth attachment, in contrast to other pterosaurs, there is no direct evidence for gomphosis in Pterodaustro (i.e. the absence of cementum, mineralized periodontal ligamentum and alveolar bone). Nevertheless, the current evidence for ankylosis is still not conclusive. Contrary to that reported for other archosaurs, replacement teeth are absent in Pterodaustro, which is interpreted as evidence for monophyodonty or diphyodonty in this taxon. Most of the microstructural features are possibly related to the complex filter-feeding apparatus of Pterodaustro and does not appear to represent the general pattern of pterosaurs.

Integrating isotopic and nutritional niches reveals multiple dimensions of individual diet specialisation in a marine apex predator.

Dietary specialisations are important determinants of ecological structure, particularly in species with high per-capita trophic influence like marine apex predators. These species are, however, among the most challenging in which to establish spatiotemporally integrated diets. We introduce a novel integration of stable isotopes with a multidimensional nutritional niche framework that addresses the challenges of establishing spatiotemporally integrated nutritional niches in wild populations, and apply the framework to explore individual diet specialisation in a marine apex predator, the white shark Carcharodon carcharias. Sequential tooth files were sampled from juvenile white sharks to establish individual isotopic (δ-space; δ13 C, δ15 N, δ34 S) niche specialisation. Bayesian mixing models were then used to reveal individual-level prey (p-space) specialisation, and further combined with nutritional geometry models to quantify the nutritional (N-space) dimensions of individual specialisation, and their relationships to prey use. Isotopic and mixing model analyses indicated juvenile white sharks as individual specialists within a broader, generalist, population niche. Individual sharks differed in their consumption of several important mesopredator species, which suggested among-individual variance in trophic roles in either pelagic or benthic food webs. However, variation in nutrient intakes was small and not consistently correlated with differences in prey use, suggesting white sharks as nutritional specialists and that individuals could use functionally and nutritionally different prey as complementary means to achieve a common nutritional goal. We identify how degrees of individual specialisation can differ between niche spaces (δ-, p- or N-space), the physiological and ecological implications of this, and argue that integrating nutrition can provide stronger, mechanistic links between diet specialisation and its intrinsic (fitness/performance) and extrinsic (ecological) outcomes. Our time-integrated framework is adaptable for examining the nutritional consequences and drivers of food use variation at the individual, population or species level.

Single-retainer all-ceramic resin-bonded fixed dental prostheses: Long-term outcomes in the esthetic zone.

OBJECTIVES: To present an update on the concept of cantilevered single-retainer all-ceramic resin-bonded fixed dental prostheses (RBFDPs) first presented 25 years ago in the Journal of Esthetic Dentistry. OVERVIEW: The initially presented case of the concept was followed clinically over 26 years and is presented along with two additional clinical long-term cases using varying methods to obtain an esthetic and hygienic ovate pontic design. Veneered alumina and zirconia ceramic (3 mol% yttria-tetragonal zirconia polycrystalline ceramic; 3Y-TZP) was used and bonded with a phosphate monomer containing luting resin after 50 µm alumina particle air-abrasion at 0.25 MPa pressure. The restorations replacing incisors did not debond and soft tissues in the pontic area were maintained over 26 years. CONCLUSIONS: Cantilevered single-retainer all-ceramic RBFDPs today made from veneered 3Y-TZP zirconia ceramic can be considered a standard of care for the replacement of single incisors and provide an excellent esthetic outcome with a long-term preservation of soft tissues in the pontic area. CLINICAL SIGNIFICANCE: Bonding nonretentive oxides ceramics such as alumina and zirconia ceramic with phosphate monomer containing luting resins after alumina particle air-abrasion is durable over decades. This proves that bonding to zirconia ceramic is not of any problem when adequate methods are used. Single-retainer zirconia ceramic RBFDPs maintain soft tissues in the edentulous area of single missing incisors and often deem implants unessential for this indication.

Facial implant gingival level and thickness changes following maxillary anterior immediate tooth replacement with scarf-connective tissue graft: A 4-13-year retrospective study.

OBJECTIVE: A scarf-shaped connective tissue graft can be placed at the facial and proximal aspect of the peri-implant soft tissue zone during immediate implant placement and provisionalization (IIPP) procedures in the esthetic zone to optimize implant esthetics without the need of flap reflection. This retrospective study evaluated soft tissue stability after scarf-connective tissue graft (S-CTG) in conjunction with IIPP procedures in the esthetic zone. MATERIALS AND METHODS: Patients who received IIPP with S-CTG with a minimum 1-year follow-up were evaluated. Mid-facial gingival level (MFGL) change and mid-facial gingival thickness (MFGT) change were measured and compared at the pre-op (T0), IIPP + S-CTG surgery (T1), follow up appointment with MFGT measurement (T2), and latest follow-up appointment (T3). Implant success rate and graft necrosis were also recorded. RESULTS: A total of 22 IIPP and S-CTG procedures in 20 patients were evaluated in the study. After a mean follow-up of 8.2 years (3.9-13.4) (T3), all implants remained osseointegrated (22/22 [100%]), with statistically insignificant mean midfacial gingival level change of -0.19 mm (-1.5 to 0.8). Statistically significant difference in midfacial gingival thickness (MFGT) was noted (2.5 mm [1.8-3.5 mm]) after a mean follow-up time (T2) of 2.3 years (1-8.6) when compared with MFGT at baseline (1.1 mm [0.6-1.3 mm]) (T1). Necrosis of S-CTG during initial healing phase was noted in 9% (2/22) of the sites. CONCLUSIONS: Within the confines of this study, scarf-connective tissue graft at time of immediate implant placement and provisionalization can thicken the gingiva and maintain the gingival level at the critical soft tissue zone. CLINICAL SIGNIFICANCE: Managing the soft tissue zone is as important as that of the hard tissue zone for peri-implant esthetics. Connective tissue graft is one of the methods that can enhance the final esthetic outcomes. This retrospective study has demonstrated that Scarf-CTG technique is an effective treatment modality to maintain soft tissue stability.

Sharp and fully loaded: 3D tissue reconstruction reveals how snake fangs stay deadly during fang replacement.

Snake venom is produced, transported and delivered by the sophisticated venom delivery system (VDS). When snakes bite, the venom travels from the venom gland through the venom duct into needle-like fangs that inject it into their prey. To counteract breakages, fangs are continuously replaced throughout life. Currently, the anatomy of the connection between the duct and the fang has not been described, and the mechanism by which the duct is reconnected to the replacement fang has not been identified. We examined the VDS in 3D in representative species from two families and one subfamily (Elapidae, Viperidae, Atractaspidinae) using contrast-enhanced microCT (diceCT), followed by dissection and histology. We observed that the venom duct bifurcates immediately anterior to the fangs so that both the original and replacement fangs are separately connected and functional in delivering venom. When a fang is absent, the canal leading to the empty position is temporarily closed. We found that elapid snakes have a crescent-shaped venom reservoir where venom likely pools before it enters the fang. These findings form the final piece of the puzzle of VDS anatomy in front-fanged venomous snakes. Additionally, they provide further evidence for independent evolution of the VDS in these three snake taxa.

A prospective association between tooth status and cognitive performance among older adults in Europe.

OBJECTIVES: This study set out to examine both the longitudinal association between tooth status and cognitive performance among older adults in Europe, and the mediating effects of loneliness and quality of life on this association. METHODS: We conducted a prospective analysis using data from 38,614 participants aged 50 or older, taken from the Survey of Health, Ageing and Retirement in Europe (SHARE) of 2013 (baseline) and 2015 (follow up). Bootstrapping with resampling strategies was used for testing a multiple mediator model. RESULTS: The average age of participants was 66.9 (SD = 9.4). About 23% of the participants had full sets of their own teeth and 38.2% had missing teeth fully replaced by dental implants or dentures. Participants who had partially replaced teeth (B = 0.038, p < 0.001), and with fully replaced teeth (B = 0.041, p < 0.001), or had all their teeth in place (B = 0.055, p < 0.001), had better cognitive performance compared to those who did not replace their missing teeth. It was also found that quality of life and loneliness partially mediated these relationships - Having all teeth in place or replacing all or partially missing teeth was found to affect cognitive performance also via improved quality of life and through lower loneliness. CONCLUSION: In later life, poor tooth status can be directly associated with cognitive decline and indirectly linked to cognitive performance, in light of decreasing quality of life and increasing loneliness. Clinicians should be aware of both the impact of poor tooth status on cognitive status and the implications for the wellbeing of older adults.

The effect of implant macrogeometry in immediate tooth replacement therapy: A case series.

The concept of immediate tooth replacement therapy (ITRT) in the esthetic zone has become a viable treatment modality and widely accepted in clinical practice. However, achieving adequate primary stability that enables immediate provisional restoration and desirable space for bone-grafting with conventional tapered body implant designs is challenging. The macro-hybrid implant design with a prosthetic angle correction and body-shift feature in a singular form provides not only greater primary stability of a wider diameter implant but also circumferential gap distance both facially and interproximally preserve the labial bone plate and interdental attachment apparatus of the adjacent natural teeth thereby maintaining the interdental papilla. The present clinical series exemplifies the clinical advantages of this inverted body-shift implant design in ITRT in various clinical scenarios in (1) single tooth replacement in a Type 1 intact socket with a thin periodontal phenotype, (2) single tooth replacement in a Type 2 socket with a dentoalveolar dehiscence of the labial bone plate, and (3) multiple adjacent teeth replacement of two maxillary central incisor. CLINICAL SIGNIFICANCE: The macro-hybrid design implant with a prosthetic angle correction and body-shift feature in a singular form provides greater midfacial gap distance as well as tooth-to-implant distance to preserve the interdental attachment of the adjacent natural teeth thereby leaving the interdental papilla undisturbed, without sacrificing higher primary stability afforded by larger diameter implants.

Gene expression patterns associated with dental replacement in the rabbit, a new model for the mammalian dental replacement mechanisms.

BACKGROUND: Unlike many vertebrates with continuous dental replacement, mammals have a maximum of two dental generations. Due to the absence of dental replacement in the laboratory mouse, the mechanisms of the mammalian tooth replacement system are poorly known. In this study, we use the European rabbit as a model for mammalian tooth development and replacement. RESULTS: We provide data on some key regulators of tooth development. We detected the presence of SOX2 in both the replacement dental lamina and the rudimentary successional dental lamina of unreplaced molars, indicating that SOX2 may not be sufficient to initiate and maintain tooth replacement. We showed that Shh does not seem to be directly involved in tooth replacement. The transient presence of the rudimentary successional dental lamina in the molar allowed us to identify genes that could be essential for the initiation or the maintenance of tooth replacement. Hence, the locations of Sostdc1, RUNX2, and LEF1 vary between the deciduous premolar, the replacement premolar, and the molar, indicating possible roles in tooth replacement. CONCLUSION: According to our observations, initiation and the maintenance of tooth replacement correlate with the presence of LEF1+ cells and the absence of both mesenchymal RUNX2 and epithelial Sostdc1+ cells.

Autotransplantation: a lost art worthy of revival in the era of implants.

While synthetic implants represent a significant contribution to the advancement of dental medicine, they are associated with high costs, potential complications, and time delays. With autotransplantation, the patient is both donor and recipient of a living tooth; in the ideal case, this procedure transfers a healthy, nonfunctional tooth to a functional position. The aim of this article is to review the literature surrounding autotransplantation and present a successful case with the hope of increasing awareness of this approach to tooth replacement. A 20-year-old patient presented with a maxillary right second molar showing poor prognosis for restoration, and the patient's financial difficulties rendered extraction the only treatment option. The patient's fully soft tissue-impacted maxillary right third molar was atraumatically extracted and transplanted as a replacement for the second molar. The autotransplantation technique was enhanced via use of bone allograft to adapt the distal portion of the socket to the transplant, immediately reestablishing a healthy bony anatomy. In addition to reviewing the biologic basis, high success rate, and advantages of tooth autotransplantation, this article introduces a naming convention for transplanted teeth.

DIRECT EVIDENCE OF THE MOLARIFORM TOOTH REPLACEMENT IN Gobiconodon borissiaki (GOBICONODONTIDAE, MAMMALIA) FROM THE EARLY CRETACEOUS OF MONGOLIA.

The maxillary fragment of eutriconodontan Gobiconodon borissiaki Trofimov, 1978 (Gobiconodontidae) is described from the Early Cretaceous Zuun-Höövör locality in Mongolia (Övörkhangai aimag, Guchin-Us sum). It demonstrates erupting М2RR (second molariform tooth of the third generation) along with the presence of the almost unworn M4R and alveoli of M3R and M5. This is the first direct evidence of the molariform tooth replacement in Gobiconodon from the Early Cretaceous of Mongolia. The CT study of the specimen revealed the absence of mineralized germs of other teeth.

FAM20B-catalyzed glycosaminoglycans control murine tooth number by restricting FGFR2b signaling.

BACKGROUND: The formation of supernumerary teeth is an excellent model for studying the molecular mechanisms that control stem/progenitor cell homeostasis needed to generate a renewable source of replacement cells and tissues. Although multiple growth factors and transcriptional factors have been associated with supernumerary tooth formation, the regulatory inputs of extracellular matrix in this regenerative process remains poorly understood. RESULTS: In this study, we present evidence that disrupting glycosaminoglycans (GAGs) in the dental epithelium of mice by inactivating FAM20B, a xylose kinase essential for GAG assembly, leads to supernumerary tooth formation in a pattern reminiscent of replacement teeth. The dental epithelial GAGs confine murine tooth number by restricting the homeostasis of Sox2(+) dental epithelial stem/progenitor cells in a non-autonomous manner. FAM20B-catalyzed GAGs regulate the cell fate of dental lamina by restricting FGFR2b signaling at the initial stage of tooth development to maintain a subtle balance between the renewal and differentiation of Sox2(+) cells. At the later cap stage, WNT signaling functions as a relay cue to facilitate the supernumerary tooth formation. CONCLUSIONS: The novel mechanism we have characterized through which GAGs control the tooth number in mice may also be more broadly relevant for potentiating signaling interactions in other tissues during development and tissue homeostasis.

New insights into patterns and rates of tooth replacement in serrasalmid and characid fishes, with implications for the subsistence fishery of Peru's remote ribereños villages.

We explored patterns, rates and unexpected socio-ecological consequences of tooth replacement in serrasalmids and characids of the Peruvian Amazon using microcomputed tomography. Of 24 specimens collected in February 2019, representing a mix of red-bellied piranha Pygocentrus nattereri, redeye piranha Serrasalmus rhombeus, silver dollar fish Ctenobrycon hauxwellianus and mojara Astyanax abramis, six individuals possessed edentulous jaw quadrants. On average, 22.9% of fish collected per day from these species featured incomplete dentition, a value three to five times higher than anticipated based on replacement rates estimated from captive fish, differences that may be driven by ontogeny, seasonality or environmental quality.

Knowledge and awareness of dental implants among Syrian refugees: a cross sectional study in Zaatari camp.

BACKGROUND: The popularity of implant dentistry is increasing dramatically, but the success of implant treatment depends on a patient's knowledge and expectations. METHODS: This study aimed to assess dental implant knowledge among refugees as a treatment option (n = 565), using face-to-face interviews. The frequency distribution of the responses in general and according to age, gender and education was calculated. RESULTS: 81.8% of the interviewees had missing teeth, however, only 26.2% replaced them. 16.6% of participants had never/hardly heard about implants. Females who never heard of implants were more than males (P < 0.001). 51.3% of participants described dental implants as a screw, and only 35.4% knew implants were placed in jawbones. 6.2% of respondents reported that implants required more care than a natural teeth, with 47.6% believing that diseases affect implant success. Friends were the main source of information (61.4%). Highly educated participants showed higher knowledge about implants. CONCLUSIONS: The surveyed sample revealed limited knowledge about dental implants with high cost being a major obstacle, warranting more strategies to increase awareness and to make implants more affordable for this population.

"BEIM ZAHNARZT": An 1899 Viennese Incisor Implant: A Case Report.

About 122 years ago, in Vienna, a dandy fellow wearing a top hat and Sunday-go-to-church custom-fitted suit, presented to a dentist for treatment. The gentleman's chief complaint was that he was "missing an upper front tooth and even when I'm dressed to the nines, none of my lady friends would go out to dinner and dancing with me"(Fig. 1). The patient was in no acute distress and explained that he had lost his shirt and golden front tooth four years prior, in a poker game, when his three Kings and two Jacks nose-dived under the four Aces laid down by the card player to his left.

Reptile enamel matrix proteins: Selection, divergence, and functional constraint.

The three major enamel matrix proteins (EMPs): amelogenin (AMEL), ameloblastin (AMBN), and enamelin (ENAM), are intrinsically linked to tooth development in tetrapods. However, reptiles and mammals exhibit significant differences in dental patterning and development, potentially affecting how EMPs evolve in each group. In most reptiles, teeth are replaced continuously throughout life, while mammals have reduced replacement to only one or two generations. Reptiles also form structurally simple, aprismatic enamel while mammalian enamel is composed of highly organized hydroxyapatite prisms. These differences, combined with reported low sequence homology in reptiles, led us to predict that reptiles may experience lower selection pressure on their EMPs as compared with mammals. However, we found that like mammals, reptile EMPs are under moderate purifying selection, with some differences evident between AMEL, AMBN, and ENAM. We also demonstrate that sequence homology in reptile EMPs is closely associated with divergence times, with more recently diverged lineages exhibiting high homology, along with strong phylogenetic signal. Lastly, despite sequence divergence, none of the reptile species in our study exhibited mutations consistent with diseases that cause degeneration of enamel (e.g. amelogenesis imperfecta). Despite short tooth retention time and simplicity in enamel structure, reptile EMPs still exhibit purifying selection required to form durable enamel.

Timing of implant placement after traumatic dental injury.

Dental implants are reliable to replace teeth lost because of traumatic dental injury. However, dental implants behave like ankylosed teeth and should not be placed in growing individuals because of the risk of infraposition. This risk may be reduced by ensuring arrested skeletal growth and ideal incisal support. The timing of implant placement may be immediate, early, conventional, or late and is determined by the extent of the trauma, remaining growth, and conditions of the hard and soft tissues. Timing should allow an observation period to properly evaluate the prognosis of concomitantly traumatized neighboring teeth. Orthodontic alignment is often necessary after traumatic dental injury in young individuals to provide symmetric dental conditions around the facial midline, to allow implant placement in the correct 3-dimensional position for the later prosthetic reconstruction, and to ensure sufficient mesiodistal space that leaves a minimum of 1.5 mm of healthy alveolar bone between the future implant and neighboring teeth. Space and stable occlusion should be maintained by bonded retainers and a splint used during the night. A partial prosthesis is usually recommended as a temporary replacement. If a fixed provisional prosthesis is required, it is crucial that it does not interfere with the remaining growth and incisal support and allows proper oral hygiene.