Q U I N T E S S E N C E I N T E R N AT I O N A L
RESTORATIVE DENTISTRY
Walter Y.H. Lam
Rehabilitation of molar-incisor hypomineralization (MIH) complicated with localized tooth surface loss: A case report Walter Y.H. Lam, BDS, MDS (Pros)1/Edward H.T. Ho, BDS, MClinDent (Pros)2/ Edmond H.N. Pow, BDS, MDS (Pros Dent), PhD3 Molar-incisor hypomineralization (MIH) is a developmental enamel hypomineralized condition characteristically involving the first permanent molars and sometimes also the incisors. The affected teeth are predisposed to tooth surface loss (TSL) which may not only compromise the esthetics and function but also endanger the pulp and longevity of the teeth. This
report describes the management of a patient with MIH complicated with localized TSL and lack of occlusal clearance due to dentoalveolar compensation. The atypical TSL pattern involved all anterior teeth and required the placement of Dahl appliances on both arches. (Quintessence Int 2014;45:377–379; doi: 10.3290/j.qi.a31540)
Key words: Dahl concept, erosion, minor axial tooth movement, molar-incisor hypomineralization, tooth surface loss, tooth wear
Molar-incisor hypomineralization (MIH) is the demarcated enamel porosity of systemic origin, affecting one or more permanent molars (usually the first molars) with or without involvement of the incisors and canines.1 Its prevalence varies widely from 2.5% to 40.2%.2 It is believed that both hereditary and developmental factors are contributory. It usually compromises the enamel hardness and therefore predisposes the
1
Postgraduate Student, Discipline of Oral Rehabilitation, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, People’s Republic of China.
2
Part-time Clinical Lecturer, Discipline of Oral Rehabilitation, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, People’s Republic of China.
3
Associate Professor, Discipline of Oral Rehabilitation, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, People’s Republic of China.
Correspondence: Dr Edmond Pow, 4/F, Oral Rehabilitation, Prince Philip Dental Hospital, 34 Hospital Road, Sai Ying Pun, Hong Kong SAR, People’s Republic of China. Email: [email protected]
VOLUME 45 • NUMBER 5 • MAY 2014
affected tooth to mechanical breakdown. Tooth surface loss (TSL) is the loss of surface tooth substance caused by mechanical and chemical (erosion) factors. A strong relationship between the presence of acid erosion and enamel hypomineralization has also been reported.3 The hypomineralized enamel may be susceptible to TSL processes. MIH teeth might be associated with pathologic TSL, and a case of linear enamel hypoplasia combined with TSL has been reported.4 MIH complicated with TSL may not only compromise the esthetics and function but also endanger the pulp and longevity of the affected teeth. TSL might be complicated by eruption of the teeth with its dentoalveolar processes which obliterate the space for any restorations.5 This report describes the rehabilitation of a patient suffering from MIH complicated with localized TSL.
377
Q U I N T E S S E N C E I N T E R N AT I O N A L L am et al
a Figs 1a to 1c
b
a
b
c
Postoperative views showing the definitive restorations.
CASE REPORT A 44-year-old man complained of shortened anterior teeth deteriorating his appearance. No erosive factors or parafunctional habits were found. Normal facial height with freeway space of 2 mm was noticed. Mild TSL confined to enamel was detected on the occlusal surface of all first premolars. Severe TSL exposing dentin and/or pulp was found on all the anterior teeth, and the left maxillary and right mandibular first molars. Enamel opacity was observed on the remaining first molars. A provisional restoration was found on the cingulum of the discolored left maxillary central incisor. Compensatory eruption of the anterior teeth and the alveolar process complicated with deepened incisal plane was observed. No interocclusal space was observed between the anterior teeth in centric occlusion (Fig 1). A diagnosis of MIH, and localized anterior TSL with dentoalveolar compensation was made.
378
Figs 2a and 2b Diagnostic wax-up on the articulated casts and Dahl appliances in situ.
b
a
Figs 3a to 3c
c
Preoperative views showing localized tooth surface loss and enamel defects.
Preventive measures were instituted and TSL progression was evaluated to be stable for 6 months. Based on the diagnostic wax-ups, 3 mm of interocclusal space was required. A nickel-chromium bite plane and provisional composite crowns (Sinfony, 3M Espe) were fabricated and luted (Ketac Cem, 3M Espe) on maxillary and mandibular anterior teeth respectively (Fig 2). Six months later, simultaneous posterior occlusal contacts were reestablished uneventfully. The appliances were removed and all anterior teeth were provisionalized for 6 weeks. Full ceramic crowns (IPS e.max Press, Ivoclar Vivadent) were fabricated and luted (Calibra, DeTrey, Dentsply). The left maxillary and right mandibular first molars were prepared for gold onlay and crown respectively. The left maxillary central incisor was managed nonsurgically and surgically, but the fistula remained unresolved. It was replaced by an implant of 4.0 × 13 mm (Astra Tech Implant System, Dentsply) with a screw-retained metal-ceramic restoration. The
VOLUME 45 • NUMBER 5 • MAY 2014
Q U I N T E S S E N C E I N T E R N AT I O N A L L am et al
patient had been followed for 6 months. All teeth, restorations, and the implant-supported crown were intact and firm (Fig 3). The patient was satisfied with the esthetics and function.
DISCUSSION In the present case, localized TSL was observed mainly on the occlusal surfaces of the incisors and first molars, which suggested that the affected teeth were first compromised by MIH followed by attrition and dentoalveolar compensation over time. Dahl appliance was used to correct the dentoalveolar compensation, by intruding the teeth in contact with the appliance and eruption of nonoccluded teeth, and recreating the lost interocclusal space for restorations. The amount of space required was determined by esthetics and diagnostic wax-ups. The increase in occlusal vertical dimension (OVD) of less than 4 mm has been shown to be well adapted in dentate subjects.6 It has been recommended to place the appliance on the arch with TSL,5 but the atypical TSL pattern in this case entailed its placement on both arches. After Dahl therapy, the OVD was restored and the dentition was rehabilitated by contemporary full coverage restorations and an implant-supported crown.
VOLUME 45 • NUMBER 5 • MAY 2014
CONCLUSION MIH may predispose to TSL. With severe TSL and a lack of interocclusal space, the Dahl concept can be utilized to facilitate the rehabilitation.
ACKNOWLEDGMENTS The authors thank John Lo, Assistant Professor of Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, for performing the implant surgery; and Mr Sam Tang for the dental laboratory work.
REFERENCES 1. Lygidakis NA, Wong F, Jälevik B, Vierrou AM, Alaluusua S, Espelid I. Best Clinical Practice Guidance for clinicians dealing with children presenting with MolarIncisor-Hypomineralisation (MIH): An EAPD Policy Document. Eur Arch Paediatr Dent 2010;11:75–81. 2. Jälevik B. Prevalence and diagnosis of Molar-Incisor-Hypomineralisation (MIH): A systematic review. Eur Arch Paediatr Dent 2010;11:59–64. 3. Kazoullis S, Seow WK, Holcombe T, Newman B, Ford D. Common dental conditions associated with dental erosion in schoolchildren in Australia. Pediatr Dent 2007;29:33–39. 4. Boston DW, Al-bargi H, Bogert M. Abrasion, erosion, and abfraction combined with linear enamel hypoplasia: a case report. Quintessence Int 1999;30:683– 687. 5. Poyser NJ, Porter RW, Briggs PF, Chana HS, Kelleher MG. The Dahl Concept: past, present and future. Br Dent J 2005;198:669–676. 6. Dahl BL, Krogstad O. The effect of a partial bite raising splint on the occlusal face height. An x-ray cephalometric study in human adults. Acta Odontol Scand 1982;40:17–24.
379
RESTORATIVE DENTISTRY
Walter Y.H. Lam
Rehabilitation of molar-incisor hypomineralization (MIH) complicated with localized tooth surface loss: A case report Walter Y.H. Lam, BDS, MDS (Pros)1/Edward H.T. Ho, BDS, MClinDent (Pros)2/ Edmond H.N. Pow, BDS, MDS (Pros Dent), PhD3 Molar-incisor hypomineralization (MIH) is a developmental enamel hypomineralized condition characteristically involving the first permanent molars and sometimes also the incisors. The affected teeth are predisposed to tooth surface loss (TSL) which may not only compromise the esthetics and function but also endanger the pulp and longevity of the teeth. This
report describes the management of a patient with MIH complicated with localized TSL and lack of occlusal clearance due to dentoalveolar compensation. The atypical TSL pattern involved all anterior teeth and required the placement of Dahl appliances on both arches. (Quintessence Int 2014;45:377–379; doi: 10.3290/j.qi.a31540)
Key words: Dahl concept, erosion, minor axial tooth movement, molar-incisor hypomineralization, tooth surface loss, tooth wear
Molar-incisor hypomineralization (MIH) is the demarcated enamel porosity of systemic origin, affecting one or more permanent molars (usually the first molars) with or without involvement of the incisors and canines.1 Its prevalence varies widely from 2.5% to 40.2%.2 It is believed that both hereditary and developmental factors are contributory. It usually compromises the enamel hardness and therefore predisposes the
1
Postgraduate Student, Discipline of Oral Rehabilitation, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, People’s Republic of China.
2
Part-time Clinical Lecturer, Discipline of Oral Rehabilitation, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, People’s Republic of China.
3
Associate Professor, Discipline of Oral Rehabilitation, Faculty of Dentistry, The University of Hong Kong, Hong Kong SAR, People’s Republic of China.
Correspondence: Dr Edmond Pow, 4/F, Oral Rehabilitation, Prince Philip Dental Hospital, 34 Hospital Road, Sai Ying Pun, Hong Kong SAR, People’s Republic of China. Email: [email protected]
VOLUME 45 • NUMBER 5 • MAY 2014
affected tooth to mechanical breakdown. Tooth surface loss (TSL) is the loss of surface tooth substance caused by mechanical and chemical (erosion) factors. A strong relationship between the presence of acid erosion and enamel hypomineralization has also been reported.3 The hypomineralized enamel may be susceptible to TSL processes. MIH teeth might be associated with pathologic TSL, and a case of linear enamel hypoplasia combined with TSL has been reported.4 MIH complicated with TSL may not only compromise the esthetics and function but also endanger the pulp and longevity of the affected teeth. TSL might be complicated by eruption of the teeth with its dentoalveolar processes which obliterate the space for any restorations.5 This report describes the rehabilitation of a patient suffering from MIH complicated with localized TSL.
377
Q U I N T E S S E N C E I N T E R N AT I O N A L L am et al
a Figs 1a to 1c
b
a
b
c
Postoperative views showing the definitive restorations.
CASE REPORT A 44-year-old man complained of shortened anterior teeth deteriorating his appearance. No erosive factors or parafunctional habits were found. Normal facial height with freeway space of 2 mm was noticed. Mild TSL confined to enamel was detected on the occlusal surface of all first premolars. Severe TSL exposing dentin and/or pulp was found on all the anterior teeth, and the left maxillary and right mandibular first molars. Enamel opacity was observed on the remaining first molars. A provisional restoration was found on the cingulum of the discolored left maxillary central incisor. Compensatory eruption of the anterior teeth and the alveolar process complicated with deepened incisal plane was observed. No interocclusal space was observed between the anterior teeth in centric occlusion (Fig 1). A diagnosis of MIH, and localized anterior TSL with dentoalveolar compensation was made.
378
Figs 2a and 2b Diagnostic wax-up on the articulated casts and Dahl appliances in situ.
b
a
Figs 3a to 3c
c
Preoperative views showing localized tooth surface loss and enamel defects.
Preventive measures were instituted and TSL progression was evaluated to be stable for 6 months. Based on the diagnostic wax-ups, 3 mm of interocclusal space was required. A nickel-chromium bite plane and provisional composite crowns (Sinfony, 3M Espe) were fabricated and luted (Ketac Cem, 3M Espe) on maxillary and mandibular anterior teeth respectively (Fig 2). Six months later, simultaneous posterior occlusal contacts were reestablished uneventfully. The appliances were removed and all anterior teeth were provisionalized for 6 weeks. Full ceramic crowns (IPS e.max Press, Ivoclar Vivadent) were fabricated and luted (Calibra, DeTrey, Dentsply). The left maxillary and right mandibular first molars were prepared for gold onlay and crown respectively. The left maxillary central incisor was managed nonsurgically and surgically, but the fistula remained unresolved. It was replaced by an implant of 4.0 × 13 mm (Astra Tech Implant System, Dentsply) with a screw-retained metal-ceramic restoration. The
VOLUME 45 • NUMBER 5 • MAY 2014
Q U I N T E S S E N C E I N T E R N AT I O N A L L am et al
patient had been followed for 6 months. All teeth, restorations, and the implant-supported crown were intact and firm (Fig 3). The patient was satisfied with the esthetics and function.
DISCUSSION In the present case, localized TSL was observed mainly on the occlusal surfaces of the incisors and first molars, which suggested that the affected teeth were first compromised by MIH followed by attrition and dentoalveolar compensation over time. Dahl appliance was used to correct the dentoalveolar compensation, by intruding the teeth in contact with the appliance and eruption of nonoccluded teeth, and recreating the lost interocclusal space for restorations. The amount of space required was determined by esthetics and diagnostic wax-ups. The increase in occlusal vertical dimension (OVD) of less than 4 mm has been shown to be well adapted in dentate subjects.6 It has been recommended to place the appliance on the arch with TSL,5 but the atypical TSL pattern in this case entailed its placement on both arches. After Dahl therapy, the OVD was restored and the dentition was rehabilitated by contemporary full coverage restorations and an implant-supported crown.
VOLUME 45 • NUMBER 5 • MAY 2014
CONCLUSION MIH may predispose to TSL. With severe TSL and a lack of interocclusal space, the Dahl concept can be utilized to facilitate the rehabilitation.
ACKNOWLEDGMENTS The authors thank John Lo, Assistant Professor of Oral and Maxillofacial Surgery, Faculty of Dentistry, The University of Hong Kong, for performing the implant surgery; and Mr Sam Tang for the dental laboratory work.
REFERENCES 1. Lygidakis NA, Wong F, Jälevik B, Vierrou AM, Alaluusua S, Espelid I. Best Clinical Practice Guidance for clinicians dealing with children presenting with MolarIncisor-Hypomineralisation (MIH): An EAPD Policy Document. Eur Arch Paediatr Dent 2010;11:75–81. 2. Jälevik B. Prevalence and diagnosis of Molar-Incisor-Hypomineralisation (MIH): A systematic review. Eur Arch Paediatr Dent 2010;11:59–64. 3. Kazoullis S, Seow WK, Holcombe T, Newman B, Ford D. Common dental conditions associated with dental erosion in schoolchildren in Australia. Pediatr Dent 2007;29:33–39. 4. Boston DW, Al-bargi H, Bogert M. Abrasion, erosion, and abfraction combined with linear enamel hypoplasia: a case report. Quintessence Int 1999;30:683– 687. 5. Poyser NJ, Porter RW, Briggs PF, Chana HS, Kelleher MG. The Dahl Concept: past, present and future. Br Dent J 2005;198:669–676. 6. Dahl BL, Krogstad O. The effect of a partial bite raising splint on the occlusal face height. An x-ray cephalometric study in human adults. Acta Odontol Scand 1982;40:17–24.
379
