Early Ceramic Crown Intervention in Adolescents With Severe Amelogenesis Imperfecta: A Clinical Case Series

ABSTRACT

Amelogenesis imperfecta (AI) is a hereditary developmental disorder that affects the enamel of teeth. Patients with AI require frequent replacements of fillings, which causes considerable distress for those affected. In this series, three cases of severe AI were treated with a total of 68 ceramic crowns (IPS e.max Press) during early adolescence. After therapy, oral health‐related quality of life improved. No endodontic complications were recorded during a follow‐up period of 4 to 6 years. Early restorative treatment with ceramic crowns for children with severe AI appears to be an excellent treatment alternative.

Summary.

• Children and adolescents with severe amelogenesis imperfecta (AI) exhibiting pain, high sensitivity, esthetic concerns, and problems with mastication should be offered prosthetic rehabilitation using single tooth ceramic crowns, allowing them to experience an OHRQoL like that of their peers.

1. Introduction

Amelogenesis imperfecta (AI) is a hereditary developmental disorder that affects tooth enamel [1]. A recent study aimed to integrate phenotype, inheritance, and genetic data, revealing that 73% had non‐syndromic and 27% syndromic AI [2]. The two major types of AI are hypoplastic and hypomineralized/hypomaturized. Hypoplastic AI involves a quantitative reduction of enamel and can present with small teeth, a thin enamel layer, and pits or grooves in the teeth; hypomineralized/hypomaturized AI is a qualitative disturbance in otherwise normal enamel formation, resulting in a rough, discolored, often brown or yellowish tooth surface. Reports indicate prevalences ranging from 1 in 700 to 1 in 14,000, depending on the population [3, 4].

The severity of enamel disturbances in AI varies; patients who are most affected present with tooth hypersensitivity, rapid tooth wear, and enamel fractures as well as alterations in color and shape, all of which compromise esthetic appearance and masticatory function [5, 6].

Pousette‐Lundgren et al. [7] showed that the longevity of composite resin restorations is significantly lower in patients with AI than in healthy controls and that patients with AI require frequent replacements of fillings. AI causes considerable distress in affected patients and their parents [6, 8, 9, 10]. Qualitative studies of adolescents with AI report severe pain, feelings of embarrassment, and difficulties dealing with dental staff who lack knowledge and understanding of their condition [6, 11]. Young individuals with AI also report decreased oral health‐related quality of life (OHRQoL) [12].

Current guidelines for restorative treatment in young children and adolescents suggest using transitional restorations that cover the surfaces of anterior teeth with direct composite resin or composite resin veneers until adulthood and recommend stainless steel crowns for first permanent molars [13]. Emerging evidence, however, supports early permanent crown therapy in young patients with AI, with reports of excellent clinical results [14, 15]. Additionally, a study of adolescents with various AI types found that ceramic enamel‐dentin bonded restorations were the most successful long‐term treatment [16].

This case series aims to provide further evidence of the benefits of early ceramic crown therapy in adolescents with severe AI, explore treatment indications, and examine how treatment affects the OHRQoL of patients with AI.

All adolescents and their parents signed informed consent forms for both the treatment protocol and the publication of the case reports. The Norwegian Regional Committee for Medical and Health Research granted ethics approval before the start of the study (REK‐Midt #65404).

2. Case Description

2.1. Case I

2.1.1. Case History

A healthy 13‐year‐old boy was referred for evaluation. His chief complaint was the poor esthetics of the anterior teeth; the enamel exhibited brown spots, was of poor quality, and had areas of partial disintegration. He had begun high school, and treatment motivation was high due to his concern about the appearance of his teeth. He felt he could not speak and smile naturally and had difficulties “being himself.” He wanted to talk and communicate unreservedly with peers but chose not to. He was withdrawn in social situations and never smiled in photographs. His mother confirmed that the boy was unwilling to show his teeth and covered his mouth with his hands when smiling, particularly around people he had just met.

2.1.2. Investigations

The clinical examination in June 2016 revealed that the permanent dentition comprised teeth 17 to 47, with some composite restorations in the molars (Figure 1A). All teeth displayed yellow‐brown discoloration and rough, hypomineralized enamel areas. Occlusal surfaces exhibited post‐eruptive enamel loss; a reduction in the vertical occlusal dimension was also noted. Gingivitis with no visible buccal plaque was found in the anterior maxillary region. On the panoramic radiograph (Figure 1B), the enamel exhibited normal thickness; however, contrast between the enamel and dentin was lower than usual. Diagnosis: Amelogenesis imperfecta of hypomature type K00.5.

FIGURE 1.

(A) Permanent dentition showing AI hypomature type. All teeth exhibit severe discoloration. (B) Panoramic radiograph at age 13. Reduced contrast between enamel and dentin. (C) After cementation of ceramic crowns on no. 13–23. (D) Six‐year follow‐up showing 24 ceramic crowns. Gingival retraction on no. 13–21 with crown margins exposed.

2.1.3. Treatment

In the first phase, treatment involved ceramic crown therapy in the anterior maxillary region, specifically teeth 13–23, and the mandibular first molars. The second phase included the placement of crowns on the maxillary first molars and in the anterior mandibular region, restoring teeth 33–43. The third phase comprised crown therapy for all premolars. In total, 24 IPS e.max (Ivoclar Vivadent AG, Schaan, Liechtenstein) crowns were placed using GC Fuji Plus cement (GC Corporation, Tokyo, Japan). Patient cooperation was excellent, and only local anesthetics were required (Figure 1C).

2.1.4. Follow‐Up

Yearly follow‐ups were conducted. The patient reported no complaints or pain after treatment. Figure 1D depicts the clinical situation at the 6‐year follow‐up. Visible crown margins were observed in four teeth due to gingival retraction, which the patient had not noticed. After prosthetic rehabilitation, the patient stated that he could now smile, show his teeth, eat, and chew in public. He was no longer ashamed of his teeth and could engage in everything he wanted to, including meeting and socializing with peers.

2.2. Case II

2.2.1. Case History

A healthy 13‐year‐old girl was referred for evaluation of suspected AI and poor anterior tooth esthetics. She was a fraternal twin, born prematurely at 30 weeks. The tooth enamel of her twin brother exhibited normal mineralization. Two paternal uncles have Usher syndrome, an autosomal recessive disorder with a possible genetic link to AI (10). At 10 years of age, steel crowns were placed on the patient's mandibular first molars to reduce abnormally high sensitivity to cold and hot drinks and to maintain the vertical occlusal dimension. She reported that poor esthetics was her chief complaint, particularly regarding the thin, pointy maxillary canines. Occasionally, she felt depressed and sad, experienced social exclusion, and could spontaneously begin crying. She also suffered from insomnia. She reported being unable to eat hard foods for fear of breaking her teeth and due to painful sensitivity. School photographs were a traumatic experience for her. She feared being asked about her teeth; she described herself as easy prey and constantly afraid of being teased or bullied by peers. Because of her teeth, she avoided smiling openly and would cover her mouth with her hand when she smiled. Her mother stated that her daughter was unable to live her own life, that she was ashamed of her teeth—their color, form, and size—and thus suffered from poor self‐esteem. The problems had escalated with age.

2.2.2. Investigations

The clinical examination in September 2016 (Figure 2A) revealed a caries‐free permanent dentition, teeth no. 17–47. The enamel appeared rough and was, to varying degrees, hypoplastic, thin, or absent, with occasional horizontal grooves. All teeth distal to the first premolar exhibited a brownish‐yellow color due to exposed dentin (Figure 2B,C). The maxillary and mandibular incisal crown shape was atypically square, with thin, fragile enamel. Posteruptive enamel breakdown was noted on most incisal and occlusal surfaces, along with a reduction in vertical occlusal height. Proximal contacts were few, and both jaws displayed spacing. On the panoramic radiograph (Figure 2D), the contrast between the enamel and dentin appeared normal; the enamel layer was thin, and occasionally absent. Diagnosis: Amelogenesis imperfecta of hypoplastic type K00.5.

FIGURE 2.

(A) Permanent dentition showing AI hypoplastic type: Atypical square crown form, lack of proximal contacts, and spacing. (B) Panoramic radiograph at 13 years showing thin and partially missing enamel and exposed dentin. (C, D) Small teeth and spacing. Posterior teeth with areas of yellow‐brown discoloration and missing enamel. (E) Six‐year follow‐up, showing ceramic crowns on no. 16–26, no. 33–35, and no. 43–45.

2.2.3. Treatment

The first step in the treatment involved intraoral modeling in composite to determine the crown size and form. Next, crown therapy was performed on all teeth from 16 to 26, as well as on all premolars and canines in the mandible. IPS e.max (Ivoclar Vivadent) crowns were then cemented with GC Fuji Plus cement. Patient cooperation was excellent, requiring only local anesthetics during the treatment.

2.2.4. Follow‐Up

At the annual follow‐ups, her oral hygiene was noted to be excellent. The patient had few complaints, seldom reported any pain, and was very happy with the results of her treatment. Figure 2E depicts the clinical situation after 6 years. She still experienced issues when drinking cold beverages, as crowns had not yet been placed on the mandibular incisors. The patient felt that there was nothing she could not do because of her teeth. She could now engage in activities she had previously avoided without feeling ashamed, such as talking, eating, and smiling with her friends. One thing she wanted to do but felt she could not was get a tongue piercing; however, she considered it not too great a sacrifice.

2.3. Case III

2.3.1. Case History

A 9‐year‐old girl was referred for evaluation. Her father and several paternal relatives had been diagnosed with AI. The patient reported multiple challenges, including poor esthetics, pain, high sensitivity, difficulties with chewing, and calculus buildup. Tooth brushing was challenging due to pain, sensitivity, and the rough enamel surface. Pain and sensitivity also prevented her from consuming hot or cold beverages. Over the years, she had developed dental anxiety, primarily because of ineffective pain control with local anesthetics.

She said that her teeth did not prevent her from doing anything and that she was always able to find a solution to the problem; however, she experienced difficulties when eating and drinking, particularly with cold foods or drinks. If she wanted to smile, she avoided showing her teeth. Her father believed that her high tooth sensitivity caused problems, but she could eat most foods despite this. He also mentioned that, apart from her struggles to smile, she appeared to be a normal child for her age and could do everything she desired.

2.3.2. Investigations

The multidisciplinary clinical examination revealed permanent dentition comprising no. 16–46 and an open bite; the molars were the only surfaces exhibiting occlusal contact (Figure 3A). All teeth presented a rough, porous surface with brownish‐yellow discoloration. Post‐eruptive enamel loss, leading to exposed dentin, was observed on both incisal and occlusal surfaces. Dental plaque and calculus covered most surfaces, and extensive gingivitis was noted. Previous treatment included composite build‐ups of incisors and temporary stainless‐steel crowns on the first permanent molars. A panoramic radiograph (Figure 3B) displayed reduced contrast between the enamel and dentin and initial mineralization of the second mandibular molars; the maxillary second molars were congenitally missing. It was determined that crown therapy should be performed before orthodontic treatment due to high tooth sensitivity. The future treatment plan includes yearly follow‐ups, orthodontics, and orthognathic surgery after growth is completed [17, 18]. Diagnosis: Amelogenesis imperfecta of hypomineralized type K00.5.

FIGURE 3.

(A) Permanent dentition showing AI hypomineralized type. Yellow‐brown discoloration with raw, and porous enamel. Posteruptive enamel breakdown on incisors restored using resin composite. Excessive amounts of supragingival calculus and gingivitis. (B) Panoramic radiograph at 9 years showing no. 17 and 27 missing and reduced contrast between enamel and dentin. (C) Follow‐up 1 year after cementation of gold crowns on no. 16 and 26; 3 years after cementation of 20 ceramic crowns on no. 15–25, 35–45; and 3 years after cementation of four gold crowns on no. 36, 37, 46, and 47.

2.3.3. Treatment

Between ages 9 and 13, resin composite treatment was used to cover exposed dentin. All procedures were performed under general anesthesia due to significant cooperation difficulties caused by extreme sensitivity to water and air. Because of this and the need to monitor occlusion development, the patient was not ready for crown therapy at 9 years old. It was also decided to delay orthodontic treatment until after crown therapy.

Treatment was performed over three sessions when the patient was 13 years old; general anesthetics were administered in each session. During the first session, crowns for the maxillary incisors, canines, and premolars were prepared. The stainless‐steel crowns on the first permanent molars were deemed satisfactory and left in place. Calculus was removed, and an impression was taken for a mandibular splint, which was subsequently cast and provided to the patient. The splint was intended for daily application of fluoride/chlorhexidine gel over the next 2 weeks, until the following treatment session; the goal was to reduce gingivitis and the accumulation of calculus.

During the second treatment session, ceramic crowns were placed on the maxilla (teeth no. 15–25). Ceramic crowns for the mandibular teeth (no. 35–45) and gold crowns for the mandibular molars were prepared. In the third session, the ceramic crowns were cemented on the mandibular teeth, and the gold crowns were placed on the molars. Gold crowns were selected to maintain vertical height and to withstand the high load on the first molars caused by the open bite. All ceramic IPS e.max and gold crowns were cemented using GC Fuji Plus cement.

2.3.4. Follow‐Up

Annual follow‐ups were done. Oral hygiene was excellent, substantially better than before crown therapy. Gingivitis and calculus accumulation were also reduced. The patient exhibited less dental anxiety than on her visits before crown therapy. She had no complaints or pain after the completion of treatment and was very happy with her oral situation at the 3‐year follow‐up (Figure 3C). During the follow‐up, the previously placed temporary crowns on the upper first permanent molars were replaced with gold crowns due to wear and loss of vertical dimension. She now has a frontal open bite of −4 mm, a skeletal mesial basal relationship, and bimaxillary retrognathia. Orthognathic surgery is planned at 19 years of age.

After crown therapy, the patient expressed that she was unable to chew hard foods because she was afraid the crowns might break, so she carefully chose soft foods. Otherwise, she was able to do everything she wanted. Her teeth did not hinder her from pursuing her desires. She could now participate in all activities she had previously avoided.

3. Discussion

This case series provides further support for the feasibility of early ceramic crown therapy in adolescents with severe AI. In all three cases, the treatment had no adverse effects. The follow‐up ranged from 4 to 6 years, and complications during follow‐up were rare: most follow‐ups reported no complications. This case series also highlights the severe impact of AI on young individuals, the limitations it imposes in their lives, and how early ceramic crown therapy can reverse these limitations.

Society today focuses on body image so intensely that even children as young as five are affected [19, 20, 21]. Social media plays a dominant role in the lives of young people; more than 90% of 9–18‐year‐olds are on one or several social media platforms. In a Norwegian Media Authority report [22], a quarter of all adolescents report having been subjected to bullying on social media, and 60% “like” someone every day. In this environment, it is easy to understand that the adolescents in this case series feel ashamed and excluded because of the appearance of their teeth. This was particularly evident regarding taking selfies and participating on social media. Being able to socialize, smile, and communicate with peers without barriers is essential during adolescence; they do not want to look different.

Having discolored teeth with an atypical shape and facing difficulties in eating and drinking presents a significant impediment, both medically and socially, among young people today. Previous studies have observed a lower quality of life among adolescents with AI than their peers [6, 12]. Studies have also found that adolescents with AI must frequently replace failed composite restorations; effective pain control is difficult, resulting in treatment fatigue and increased dental fear and anxiety [7, 13].

Patients in this case series were informed that permanent crown therapy could not be undertaken before the age of 21, which was extremely frustrating for them since AI was having such a large impact on their lives. All three patients wanted permanent therapy at an earlier age. A recent analysis of early crown therapy found that treatment in early adolescence was cost‐effective: placing crowns had a high success rate and avoided the frequent replacements of failed composite resin restorations that often occurred [23].

This study's IPS e.max ceramic crowns consist of lithium disilicate, known for their high strength, excellent esthetics, and good long‐term performance. They are particularly suitable for the anterior region, where esthetic demands are high. It is also superior to direct and prefabricated resin composite restorations [16]. In hypoplastic AI, as in case B, the naturally occurring space between the teeth can be utilized if treatment begins before the mesial drift of the teeth. Less enamel must be removed, allowing the crowns to have a more natural form.

We placed 68 crowns in the three patients in this case series. Most of the crowns were of excellent quality. The porcelain of one crown fractured, necessitating its replacement, while minor chipping was observed in the porcelain of six crowns. The smooth surfaces of the crowns, along with less plaque retention, may explain the lower calculus build‐up. Additionally, reduced tooth sensitivity allowed for improved oral hygiene.

During the follow‐up, there were still no endodontic complications from treatment. One study in 2012 discusses the risk of pulpal complications due to large pulp chambers [13]; another study did not find this to be a risk with new porcelain materials, which required only minimal preparation [14]. A 5‐year follow‐up of a randomized controlled trial of Procera or IPS e.max Press crown therapy reported a survival rate of 99.6%, a success rate of 94.7%, and excellent or acceptable quality for 97% of the crowns. Endodontic complications occurred in 3% of the teeth, all of which had a history of traumatic injury [14]. Large pulp chambers in young permanent teeth have good blood supply and a lower risk of complications after preparation for crown therapy [24].

Among the cases in this study, two patients received only local anesthesia while one was treated under general anesthesia. The sensitivity of other teeth must be considered during restoration; it is not uncommon for patients to complain of sensitivity in the opposite jaw. When tooth sensitivity is present in patients with AI, dental treatment using analgesic drugs, local anesthesia, sedation (e.g., nitrous oxide), or general anesthetics should be considered. It is often challenging to achieve effective pain control using local anesthetics only; dental fear and anxiety, as well as exposed dentin with ensuing pulpal inflammation, may contribute to this [10].

An orthodontic evaluation is part of treatment planning in AI cases. In cases 1 and 2 in this series, the main concerns were esthetic issues caused by enamel defects, pain, and a fear of emergencies due to enamel fractures. Beginning orthodontic treatment would have extended the period of social avoidance, made eating more difficult, and created challenges for maintaining oral hygiene during this critical stage of life. Specifically, the vertical occlusal dimension is taken into consideration when planning prosthetic therapy. Since all crowns were properly positioned based on root alignment, orthodontic treatment could be performed after crown placement if needed.

As we advance, intervention in adolescent patients with severe AI will likely occur earlier, be more radical than it has been, and include ceramic crowns. Several recent authors suggest that patients with severe AI begin permanent therapy in adolescence [5, 14, 21, 25].

Author Contributions

Runa Das: conceptualization, investigation, writing – review and editing. Eva Børstad: conceptualization, investigation, writing – review and editing. Astrid Jullumstrø Feuerherm: project administration, resources, writing – review and editing. Marit Slåttelid Skeie: project administration, writing – review and editing. Gunilla Pousette Lundgren: conceptualization, investigation, writing – review and editing. Göran Dahllöf: conceptualization, supervision, writing – original draft, writing – review and editing.

Ethics Statement

This study was conducted in accordance with the Declaration of Helsinki. The Norwegian Regional Committee for Medical and Health Research granted ethics approval before the start of the study (REK‐Midt #65404). Written informed consent was obtained from all participants.

Consent

Informed consent was obtained from all subjects involved in the study. Written informed consent was obtained from the patients' parents to publish this paper.

Conflicts of Interest

The authors declare no conflicts of interest.

Das R., Børstad E., Jullumstrø Feuerherm A., Slåttelid Skeie M., Lundgren G. P., and Dahllöf G., “Early Ceramic Crown Intervention in Adolescents With Severe Amelogenesis Imperfecta: A Clinical Case Series,” Clinical Case Reports 13, no. 10 (2025): e71202, 10.1002/ccr3.71202.

Data Availability Statement

The authors have nothing to report.