Table 1.

Tooth size reduction in tooth agenesis Japanese patients

	Control (C)	Hypodintia (H)	Oligodontia (O)	C vs H		C vs O		H vs O
	Mean ± S.D.	Mean ± S.D.	Mean ± S.D.	Difference	Significance	Difference	Significance	Difference	Significance
Male
Maxilla
Central incisor	8.81 ± 0.51	8.60 ± 0.62	8.22 ± 0.76	− 0.21	NS	− 0.59	**	− 0.38	*
Lateral incisor	7.40 ± 0.56	7.37 ± 1.00	6.43 ± 0.90	− 0.03	NS	− 0.97	**	− 0.94	**
Canine	8.38 ± 0.41	8.20 ± 0.56	7.94 ± 0.55	− 0.18	NS	− 0.44	**	− 0.26	*
First premolar	7.75 ± 0.44	7.77 ± 0.62	6.93 ± 0.40	0.02	NS	− 0.82	**	− 0.84	**
Second premolar	7.22 ± 0.50	7.13 ± 0.54	6.78 ± 0.46	− 0.09	NS	− 0.44	NS	− 0.35	NS
First molar	10.90 ± 0.69	10.99 ± 0.75	10.29 ± 0.75	0.09	NS	− 0.61	**	− 0.7	**
Mandible
Central incisor	5.60 ± 0.37	5.79 ± 0.61	5.42 ± 0.39	0.19	NS	− 0.18	*	− 0.37	**
Lateral incisor	6.21 ± 0.43	6.21 ± 0.60	5.91 ± 0.50	0	NS	− 0.3	*	− 0.3	*
Canine	7.29 ± 0.39	7.16 ± 0.47	6.98 ± 0.46	− 0.13	NS	− 0.31	*	− 0.18	NS
First premolar	7.70 ± 0.37	7.69 ± 0.55	7.20 ± 0.47	−0.01	NS	− 0.5	**	− 0.49	**
Second premolar	7.64 ± 0.46	7.54 ± 0.46	7.13 ± 0.25	− 0.1	NS	− 0.51	NS	− 0.41	NS
First molar	11.76 ± 0.59	11.74 ± 0.71	11.32 ± 0.64	− 0.02	NS	− 0.44	**	−0.42	*
Female
Maxilla
Central incisor	8.69 ± 0.49	8.58 ± 0.49	8.05 ± 0.82	− 0.11	NS	− 0.64	**	− 0.53	**
Lateral incisor	7.29 ± 0.69	6.94 ± 0.89	6.06 ± 1.10	− 0.35	*	−1.23	**	− 0.88	**
Canine	7.98 ± 0.46	7.97 ± 0.49	7.76 ± 0.65	− 0.01	NS	− 0.22	NS	− 0.21	NS
First premolar	7.67 ± 0.43	7.51 ± 0.55	7.29 ± 0.58	− 0.16	NS	−0.38	*	−0.22	NS
Second premolar	7.08 ± 0.47	7.05 ± 0.57	7.20 ± 0.88	− 0.03	NS	0.12	NS	0.15	NS
First molar	10.62 ± 0.38	10.51 ± 0.60	10.35 ± 0.51	− 0.11	NS	− 0.27	*	− 0.16	NS
Mandible
Central incisor	5.61 ± 0.37	5.66 ± 0.45	5.36 ± 0.57	0.05	NS	− 0.25	NS	− 0.3	*
Lateral incisor	6.19 ± 0.37	6.07 ± 0.50	5.65 ± 0.41	− 0.12	NS	− 0.54	**	− 0.42	**
Canine	6.86 ± 0.44	6.84 ± 0.49	6.60 ± 0.64	− 0.02	NS	− 0.26	NS	− 0.24	NS
First premolar	7.51 ± 0.43	7.46 ± 0.50	6.95 ± 0.56	− 0.05	NS	− 0.56	**	− 0.51	*
Second premolar	7.42 ± 0.44	7.34 ± 0.49	6.67 ± 1.17	− 0.08	NS	− 0.75	NS	− 0.67	NS
First molar	11.38 ± 0.48	11.01 ± 0.61	11.05 ± 0.89	− 0.37	**	− 0.33	NS	0.04	NS

NS not significant; *p < 0.05, **p < 0.01